-----BEGIN PGP SIGNATURE-----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=s1UQ
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fix from Thomas Gleixner:
"A single bugfix to prevent reference leaks in irq affinity notifiers"
* tag 'irq-urgent-2020-03-29' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Fix reference leaks on irq affinity notifiers
Depending on CONFIG_VMAP_STACK and the THREAD_SIZE / PAGE_SIZE ratio the
space for task stacks can be allocated using __vmalloc_node_range(),
alloc_pages_node() and kmem_cache_alloc_node().
In the first and the second cases page->mem_cgroup pointer is set, but
in the third it's not: memcg membership of a slab page should be
determined using the memcg_from_slab_page() function, which looks at
page->slab_cache->memcg_params.memcg . In this case, using
mod_memcg_page_state() (as in account_kernel_stack()) is incorrect:
page->mem_cgroup pointer is NULL even for pages charged to a non-root
memory cgroup.
It can lead to kernel_stack per-memcg counters permanently showing 0 on
some architectures (depending on the configuration).
In order to fix it, let's introduce a mod_memcg_obj_state() helper,
which takes a pointer to a kernel object as a first argument, uses
mem_cgroup_from_obj() to get a RCU-protected memcg pointer and calls
mod_memcg_state(). It allows to handle all possible configurations
(CONFIG_VMAP_STACK and various THREAD_SIZE/PAGE_SIZE values) without
spilling any memcg/kmem specifics into fork.c .
Note: This is a special version of the patch created for stable
backports. It contains code from the following two patches:
- mm: memcg/slab: introduce mem_cgroup_from_obj()
- mm: fork: fix kernel_stack memcg stats for various stack implementations
[guro@fb.com: introduce mem_cgroup_from_obj()]
Link: http://lkml.kernel.org/r/20200324004221.GA36662@carbon.dhcp.thefacebook.com
Fixes: 4d96ba3530 ("mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages")
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Bharata B Rao <bharata@linux.ibm.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200303233550.251375-1-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A recent change to freeze_secondary_cpus() which added an early abort if a
wakeup is pending missed the fact that the function is also invoked for
shutdown, reboot and kexec via disable_nonboot_cpus().
In case of disable_nonboot_cpus() the wakeup event needs to be ignored as
the purpose is to terminate the currently running kernel.
Add a 'suspend' argument which is only set when the freeze is in context of
a suspend operation. If not set then an eventually pending wakeup event is
ignored.
Fixes: a66d955e91 ("cpu/hotplug: Abort disabling secondary CPUs if wakeup is pending")
Reported-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Pavankumar Kondeti <pkondeti@codeaurora.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/874kuaxdiz.fsf@nanos.tec.linutronix.de
Move access_ok() in and pagefault_enable()/pagefault_disable() out.
Mechanical conversion only - some instances don't really need
a separate access_ok() at all (e.g. the ones only using
get_user()/put_user(), or architectures where access_ok()
is always true); we'll deal with that in followups.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Enable the bpf_get_current_cgroup_id() helper for connect(), sendmsg(),
recvmsg() and bind-related hooks in order to retrieve the cgroup v2
context which can then be used as part of the key for BPF map lookups,
for example. Given these hooks operate in process context 'current' is
always valid and pointing to the app that is performing mentioned
syscalls if it's subject to a v2 cgroup. Also with same motivation of
commit 7723628101 ("bpf: Introduce bpf_skb_ancestor_cgroup_id helper")
enable retrieval of ancestor from current so the cgroup id can be used
for policy lookups which can then forbid connect() / bind(), for example.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/d2a7ef42530ad299e3cbb245e6c12374b72145ef.1585323121.git.daniel@iogearbox.net
In Cilium we're mainly using BPF cgroup hooks today in order to implement
kube-proxy free Kubernetes service translation for ClusterIP, NodePort (*),
ExternalIP, and LoadBalancer as well as HostPort mapping [0] for all traffic
between Cilium managed nodes. While this works in its current shape and avoids
packet-level NAT for inter Cilium managed node traffic, there is one major
limitation we're facing today, that is, lack of netns awareness.
In Kubernetes, the concept of Pods (which hold one or multiple containers)
has been built around network namespaces, so while we can use the global scope
of attaching to root BPF cgroup hooks also to our advantage (e.g. for exposing
NodePort ports on loopback addresses), we also have the need to differentiate
between initial network namespaces and non-initial one. For example, ExternalIP
services mandate that non-local service IPs are not to be translated from the
host (initial) network namespace as one example. Right now, we have an ugly
work-around in place where non-local service IPs for ExternalIP services are
not xlated from connect() and friends BPF hooks but instead via less efficient
packet-level NAT on the veth tc ingress hook for Pod traffic.
On top of determining whether we're in initial or non-initial network namespace
we also have a need for a socket-cookie like mechanism for network namespaces
scope. Socket cookies have the nice property that they can be combined as part
of the key structure e.g. for BPF LRU maps without having to worry that the
cookie could be recycled. We are planning to use this for our sessionAffinity
implementation for services. Therefore, add a new bpf_get_netns_cookie() helper
which would resolve both use cases at once: bpf_get_netns_cookie(NULL) would
provide the cookie for the initial network namespace while passing the context
instead of NULL would provide the cookie from the application's network namespace.
We're using a hole, so no size increase; the assignment happens only once.
Therefore this allows for a comparison on initial namespace as well as regular
cookie usage as we have today with socket cookies. We could later on enable
this helper for other program types as well as we would see need.
(*) Both externalTrafficPolicy={Local|Cluster} types
[0] https://github.com/cilium/cilium/blob/master/bpf/bpf_sock.c
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/c47d2346982693a9cf9da0e12690453aded4c788.1585323121.git.daniel@iogearbox.net
Daniel Borkmann says:
====================
pull-request: bpf 2020-03-27
The following pull-request contains BPF updates for your *net* tree.
We've added 3 non-merge commits during the last 4 day(s) which contain
a total of 4 files changed, 25 insertions(+), 20 deletions(-).
The main changes are:
1) Explicitly memset the bpf_attr structure on bpf() syscall to avoid
having to rely on compiler to do so. Issues have been noticed on
some compilers with padding and other oddities where the request was
then unexpectedly rejected, from Greg Kroah-Hartman.
2) Sanitize the bpf_struct_ops TCP congestion control name in order to
avoid problematic characters such as whitespaces, from Martin KaFai Lau.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
There's currently a way to select a task that should only have its events
traced, but there's no way to select a task not to have itsevents traced.
Add a set_event_notrace_pid file that acts the same as set_event_pid (and is
also affected by event-fork), but the task pids in this file will not be
traced even if they are listed in the set_event_pid file. This makes it easy
for tools like trace-cmd to "hide" itself from beint traced by events when
it is recording other tasks.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
There's currently a way to select a task that should only be traced by
functions, but there's no way to select a task not to be traced by the
function tracer. Add a set_ftrace_notrace_pid file that acts the same as
set_ftrace_pid (and is also affected by function-fork), but the task pids in
this file will not be traced even if they are listed in the set_ftrace_pid
file. This makes it easy for tools like trace-cmd to "hide" itself from the
function tracer when it is recording other tasks.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The set_ftrace_pid file is used to filter function tracing to only trace
tasks that are listed in that file. Instead of testing the pids listed in
that file (it's a bitmask) at each function trace event, the logic is done
via a sched_switch hook. A flag is set when the next task to run is in the
list of pids in the set_ftrace_pid file. But the sched_switch hook is not at
the exact location of when the task switches, and the flag gets set before
the task to be traced actually runs. This leaves a residue of traced
functions that do not belong to the pid that should be filtered on.
By changing the logic slightly, where instead of having a boolean flag to
test, record the pid that should be traced, with special values for not to
trace and always trace. Then at each function call, a check will be made to
see if the function should be ignored, or if the current pid matches the
function that should be traced, and only trace if it matches (or if it has
the special value to always trace).
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Have the ring_buffer_iterator set a flag if events were dropped as it were
to go and peek at the next event. Have the trace file display this fact if
it happened with a "LOST EVENTS" message.
Link: http://lkml.kernel.org/r/20200317213417.045858900@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When opening the "trace" file, it is no longer necessary to disable tracing.
Note, a new option is created called "pause-on-trace", when set, will cause
the trace file to emulate its original behavior.
Link: http://lkml.kernel.org/r/20200317213416.903351225@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Now that the iterator can handle a concurrent writer, do not disable writing
to the ring buffer when there is an iterator present.
Link: http://lkml.kernel.org/r/20200317213416.759770696@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When the ring buffer becomes writable for even when the trace file is read,
it must still not be resized. But since tracers can be activated while the
trace file is being read, the irqsoff tracer can modify the per CPU buffers,
and this can cause the reader of the trace file to update the wrong buffer's
resize disable bit, as the irqsoff tracer swaps out cpu buffers.
By making the resize disable per cpu_buffer, it makes the update follow the
per cpu_buffer even if it's swapped out with the snapshot buffer and keeps
the release of the trace file modifying the same data as the open did.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The PERF_SAMPLE_CGROUP bit is to save (perf_event) cgroup information in
the sample. It will add a 64-bit id to identify current cgroup and it's
the file handle in the cgroup file system. Userspace should use this
information with PERF_RECORD_CGROUP event to match which cgroup it
belongs.
I put it before PERF_SAMPLE_AUX for simplicity since it just needs a
64-bit word. But if we want bigger samples, I can work on that
direction too.
Committer testing:
$ pahole perf_sample_data | grep -w cgroup -B5 -A5
/* --- cacheline 4 boundary (256 bytes) was 56 bytes ago --- */
struct perf_regs regs_intr; /* 312 16 */
/* --- cacheline 5 boundary (320 bytes) was 8 bytes ago --- */
u64 stack_user_size; /* 328 8 */
u64 phys_addr; /* 336 8 */
u64 cgroup; /* 344 8 */
/* size: 384, cachelines: 6, members: 22 */
/* padding: 32 */
};
$
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lore.kernel.org/lkml/20200325124536.2800725-3-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
To support cgroup tracking, add CGROUP event to save a link between
cgroup path and id number. This is needed since cgroups can go away
when userspace tries to read the cgroup info (from the id) later.
The attr.cgroup bit was also added to enable cgroup tracking from
userspace.
This event will be generated when a new cgroup becomes active.
Userspace might need to synthesize those events for existing cgroups.
Committer testing:
From the resulting kernel, using /sys/kernel/btf/vmlinux:
$ pahole perf_event_attr | grep -w cgroup -B5 -A1
__u64 write_backward:1; /* 40:27 8 */
__u64 namespaces:1; /* 40:28 8 */
__u64 ksymbol:1; /* 40:29 8 */
__u64 bpf_event:1; /* 40:30 8 */
__u64 aux_output:1; /* 40:31 8 */
__u64 cgroup:1; /* 40:32 8 */
__u64 __reserved_1:31; /* 40:33 8 */
$
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
[staticize perf_event_cgroup function]
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Zefan Li <lizefan@huawei.com>
Link: http://lore.kernel.org/lkml/20200325124536.2800725-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Factor out logic mapping expected program attach type to program type and
subsequent handling of program attach/detach. Also list out all supported
cgroup BPF program types explicitly to prevent accidental bugs once more
program types are added to a mapping. Do the same for prog_query API.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200325065746.640559-3-andriin@fb.com
Refactor cgroup attach/detach code to abstract away common operations
performed on all types of cgroup storages. This makes high-level logic more
apparent, plus allows to reuse more code across multiple functions.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200325065746.640559-2-andriin@fb.com
Currently, for all op verification we call __red_deduce_bounds() and
__red_bound_offset() but we only call __update_reg_bounds() in bitwise
ops. However, we could benefit from calling __update_reg_bounds() in
BPF_ADD, BPF_SUB, and BPF_MUL cases as well.
For example, a register with state 'R1_w=invP0' when we subtract from
it,
w1 -= 2
Before coerce we will now have an smin_value=S64_MIN, smax_value=U64_MAX
and unsigned bounds umin_value=0, umax_value=U64_MAX. These will then
be clamped to S32_MIN, U32_MAX values by coerce in the case of alu32 op
as done in above example. However tnum will be a constant because the
ALU op is done on a constant.
Without update_reg_bounds() we have a scenario where tnum is a const
but our unsigned bounds do not reflect this. By calling update_reg_bounds
after coerce to 32bit we further refine the umin_value to U64_MAX in the
alu64 case or U32_MAX in the alu32 case above.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158507151689.15666.566796274289413203.stgit@john-Precision-5820-Tower
Pull per op ALU logic into individual functions. We are about to add
u32 versions of each of these by pull them out the code gets a bit
more readable here and nicer in the next patch.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/158507149518.15666.15672349629329072411.stgit@john-Precision-5820-Tower
Overlapping header include additions in macsec.c
A bug fix in 'net' overlapping with the removal of 'version'
string in ena_netdev.c
Overlapping test additions in selftests Makefile
Overlapping PCI ID table adjustments in iwlwifi driver.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Fix deadlock in bpf_send_signal() from Yonghong Song.
2) Fix off by one in kTLS offload of mlx5, from Tariq Toukan.
3) Add missing locking in iwlwifi mvm code, from Avraham Stern.
4) Fix MSG_WAITALL handling in rxrpc, from David Howells.
5) Need to hold RTNL mutex in tcindex_partial_destroy_work(), from Cong
Wang.
6) Fix producer race condition in AF_PACKET, from Willem de Bruijn.
7) cls_route removes the wrong filter during change operations, from
Cong Wang.
8) Reject unrecognized request flags in ethtool netlink code, from
Michal Kubecek.
9) Need to keep MAC in reset until PHY is up in bcmgenet driver, from
Doug Berger.
10) Don't leak ct zone template in act_ct during replace, from Paul
Blakey.
11) Fix flushing of offloaded netfilter flowtable flows, also from Paul
Blakey.
12) Fix throughput drop during tx backpressure in cxgb4, from Rahul
Lakkireddy.
13) Don't let a non-NULL skb->dev leave the TCP stack, from Eric
Dumazet.
14) TCP_QUEUE_SEQ socket option has to update tp->copied_seq as well,
also from Eric Dumazet.
15) Restrict macsec to ethernet devices, from Willem de Bruijn.
16) Fix reference leak in some ethtool *_SET handlers, from Michal
Kubecek.
17) Fix accidental disabling of MSI for some r8169 chips, from Heiner
Kallweit.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (138 commits)
net: Fix CONFIG_NET_CLS_ACT=n and CONFIG_NFT_FWD_NETDEV={y, m} build
net: ena: Add PCI shutdown handler to allow safe kexec
selftests/net/forwarding: define libs as TEST_PROGS_EXTENDED
selftests/net: add missing tests to Makefile
r8169: re-enable MSI on RTL8168c
net: phy: mdio-bcm-unimac: Fix clock handling
cxgb4/ptp: pass the sign of offset delta in FW CMD
net: dsa: tag_8021q: replace dsa_8021q_remove_header with __skb_vlan_pop
net: cbs: Fix software cbs to consider packet sending time
net/mlx5e: Do not recover from a non-fatal syndrome
net/mlx5e: Fix ICOSQ recovery flow with Striding RQ
net/mlx5e: Fix missing reset of SW metadata in Striding RQ reset
net/mlx5e: Enhance ICOSQ WQE info fields
net/mlx5_core: Set IB capability mask1 to fix ib_srpt connection failure
selftests: netfilter: add nfqueue test case
netfilter: nft_fwd_netdev: allow to redirect to ifb via ingress
netfilter: nft_fwd_netdev: validate family and chain type
netfilter: nft_set_rbtree: Detect partial overlaps on insertion
netfilter: nft_set_rbtree: Introduce and use nft_rbtree_interval_start()
netfilter: nft_set_pipapo: Separate partial and complete overlap cases on insertion
...
Add volatile current->state to list of implicitly atomic accesses. This
is in preparation to eventually enable KCSAN on kernel/sched (which
currently still has KCSAN_SANITIZE := n).
Since accesses that match the special check in atomic.h are rare, it
makes more sense to move this check to the slow-path, avoiding the
additional compare in the fast-path. With the microbenchmark, a speedup
of ~6% is measured.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Adds CONFIG_KCSAN_VERBOSE to optionally enable more verbose reports.
Currently information about the reporting task's held locks and IRQ
trace events are shown, if they are enabled.
Signed-off-by: Marco Elver <elver@google.com>
Suggested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add option to allow interrupts while a watchpoint is set up. This can be
enabled either via CONFIG_KCSAN_INTERRUPT_WATCHER or via the boot
parameter 'kcsan.interrupt_watcher=1'.
Note that, currently not all safe per-CPU access primitives and patterns
are accounted for, which could result in false positives. For example,
asm-generic/percpu.h uses plain operations, which by default are
instrumented. On interrupts and subsequent accesses to the same
variable, KCSAN would currently report a data race with this option.
Therefore, this option should currently remain disabled by default, but
may be enabled for specific test scenarios.
To avoid new warnings, changes all uses of smp_processor_id() to use the
raw version (as already done in kcsan_found_watchpoint()). The exact SMP
processor id is for informational purposes in the report, and
correctness is not affected.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This changes __pidfd_fget to use the new exec_update_mutex
instead of cred_guard_mutex.
This should be safe, as the credentials do not change
before exec_update_mutex is locked. Therefore whatever
file access is possible with holding the cred_guard_mutex
here is also possbile with the exec_update_mutex.
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This changes perf_event_set_clock to use the new exec_update_mutex
instead of cred_guard_mutex.
This should be safe, as the credentials are only used for reading.
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This changes kcmp_epoll_target to use the new exec_update_mutex
instead of cred_guard_mutex.
This should be safe, as the credentials are only used for reading,
and furthermore ->mm and ->sighand are updated on execve,
but only under the new exec_update_mutex.
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This removes an outdated comment in prepare_kernel_cred.
There is no "cred_replace_mutex" any more, so the comment must
go away.
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
This fixes a deadlock in the tracer when tracing a multi-threaded
application that calls execve while more than one thread are running.
I observed that when running strace on the gcc test suite, it always
blocks after a while, when expect calls execve, because other threads
have to be terminated. They send ptrace events, but the strace is no
longer able to respond, since it is blocked in vm_access.
The deadlock is always happening when strace needs to access the
tracees process mmap, while another thread in the tracee starts to
execve a child process, but that cannot continue until the
PTRACE_EVENT_EXIT is handled and the WIFEXITED event is received:
strace D 0 30614 30584 0x00000000
Call Trace:
__schedule+0x3ce/0x6e0
schedule+0x5c/0xd0
schedule_preempt_disabled+0x15/0x20
__mutex_lock.isra.13+0x1ec/0x520
__mutex_lock_killable_slowpath+0x13/0x20
mutex_lock_killable+0x28/0x30
mm_access+0x27/0xa0
process_vm_rw_core.isra.3+0xff/0x550
process_vm_rw+0xdd/0xf0
__x64_sys_process_vm_readv+0x31/0x40
do_syscall_64+0x64/0x220
entry_SYSCALL_64_after_hwframe+0x44/0xa9
expect D 0 31933 30876 0x80004003
Call Trace:
__schedule+0x3ce/0x6e0
schedule+0x5c/0xd0
flush_old_exec+0xc4/0x770
load_elf_binary+0x35a/0x16c0
search_binary_handler+0x97/0x1d0
__do_execve_file.isra.40+0x5d4/0x8a0
__x64_sys_execve+0x49/0x60
do_syscall_64+0x64/0x220
entry_SYSCALL_64_after_hwframe+0x44/0xa9
This changes mm_access to use the new exec_update_mutex
instead of cred_guard_mutex.
This patch is based on the following patch by Eric W. Biederman:
"[PATCH 0/5] Infrastructure to allow fixing exec deadlocks"
Link: https://lore.kernel.org/lkml/87v9ne5y4y.fsf_-_@x220.int.ebiederm.org/
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
The cred_guard_mutex is problematic as it is held over possibly
indefinite waits for userspace. The possible indefinite waits for
userspace that I have identified are: The cred_guard_mutex is held in
PTRACE_EVENT_EXIT waiting for the tracer. The cred_guard_mutex is
held over "put_user(0, tsk->clear_child_tid)" in exit_mm(). The
cred_guard_mutex is held over "get_user(futex_offset, ...") in
exit_robust_list. The cred_guard_mutex held over copy_strings.
The functions get_user and put_user can trigger a page fault which can
potentially wait indefinitely in the case of userfaultfd or if
userspace implements part of the page fault path.
In any of those cases the userspace process that the kernel is waiting
for might make a different system call that winds up taking the
cred_guard_mutex and result in deadlock.
Holding a mutex over any of those possibly indefinite waits for
userspace does not appear necessary. Add exec_update_mutex that will
just cover updating the process during exec where the permissions and
the objects pointed to by the task struct may be out of sync.
The plan is to switch the users of cred_guard_mutex to
exec_update_mutex one by one. This lets us move forward while still
being careful and not introducing any regressions.
Link: https://lore.kernel.org/lkml/20160921152946.GA24210@dhcp22.suse.cz/
Link: https://lore.kernel.org/lkml/AM6PR03MB5170B06F3A2B75EFB98D071AE4E60@AM6PR03MB5170.eurprd03.prod.outlook.com/
Link: https://lore.kernel.org/linux-fsdevel/20161102181806.GB1112@redhat.com/
Link: https://lore.kernel.org/lkml/20160923095031.GA14923@redhat.com/
Link: https://lore.kernel.org/lkml/20170213141452.GA30203@redhat.com/
Ref: 45c1a159b85b ("Add PTRACE_O_TRACEVFORKDONE and PTRACE_O_TRACEEXIT facilities.")
Ref: 456f17cd1a28 ("[PATCH] user-vm-unlock-2.5.31-A2")
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Use separate functions for the device core to bring a CPU up and down.
Users outside the device core must use add/remove_cpu() which will take
care of extra housekeeping work like keeping sysfs in sync.
Make cpu_up/down() static and replace the extra layer of indirection.
[ tglx: Removed the extra wrapper functions and adjusted function names ]
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323135110.30522-18-qais.yousef@arm.com
This is the last direct user of cpu_up() before it can become an internal
implementation detail of the cpu subsystem.
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323135110.30522-17-qais.yousef@arm.com
The core device API performs extra housekeeping bits that are missing
from directly calling cpu_up/down().
See commit a6717c01dd ("powerpc/rtas: use device model APIs and
serialization during LPM") for an example description of what might go
wrong.
This also prepares to make cpu_up/down() a private interface of the CPU
subsystem.
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: "Paul E. McKenney" <paulmck@kernel.org>
Link: https://lkml.kernel.org/r/20200323135110.30522-16-qais.yousef@arm.com
arm64 uses cpu_up() in the resume from hibernation code to ensure that the
CPU on which the system hibernated is online. Provide a core function for
this.
[ tglx: Split out from the combo arm64 patch ]
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200323135110.30522-9-qais.yousef@arm.com
This function will be used later in machine_shutdown() for some
architectures.
disable_nonboot_cpus() is not safe to use when doing machine_down(),
because it relies on freeze_secondary_cpus() which in turn is a
suspend/resume related freeze and could abort if the logic detects any
pending activities that can prevent finishing the offlining process.
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200323135110.30522-3-qais.yousef@arm.com
The new functions use device_{online,offline}() which are userspace safe.
This is in preparation to move cpu_{up, down} kernel users to use a safer
interface that is not racy with userspace.
Suggested-by: "Paul E. McKenney" <paulmck@kernel.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lkml.kernel.org/r/20200323135110.30522-2-qais.yousef@arm.com
Some .gitignore files have comments like "Generated files",
"Ignore generated files" at the header part, but they are
too obvious.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Pull RCU changes from Paul E. McKenney:
- Make kfree_rcu() use kfree_bulk() for added performance
- RCU updates
- Callback-overload handling updates
- Tasks-RCU KCSAN and sparse updates
- Locking torture test and RCU torture test updates
- Documentation updates
- Miscellaneous fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The warning was intended to spot complete_all() users from hardirq
context on PREEMPT_RT. The warning as-is will also trigger in interrupt
handlers, which are threaded on PREEMPT_RT, which was not intended.
Use lockdep_assert_RT_in_threaded_ctx() which triggers in non-preemptive
context on PREEMPT_RT.
Fixes: a5c6234e10 ("completion: Use simple wait queues")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200323152019.4qjwluldohuh3by5@linutronix.de
ARCH_SAVE_PAGE_KEYS has been introduced in order to be able to save
and restore s390 specific storage keys into a hibernation image.
With hibernation support removed from s390 there is no point in
keeping the callbacks.
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Peter Oberparleiter <oberpar@linux.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Commit 3f8fd02b1b ("mm/vmalloc: Sync unmappings in
__purge_vmap_area_lazy()") introduced a call to vmalloc_sync_all() in
the vunmap() code-path. While this change was necessary to maintain
correctness on x86-32-pae kernels, it also adds additional cycles for
architectures that don't need it.
Specifically on x86-64 with CONFIG_VMAP_STACK=y some people reported
severe performance regressions in micro-benchmarks because it now also
calls the x86-64 implementation of vmalloc_sync_all() on vunmap(). But
the vmalloc_sync_all() implementation on x86-64 is only needed for newly
created mappings.
To avoid the unnecessary work on x86-64 and to gain the performance
back, split up vmalloc_sync_all() into two functions:
* vmalloc_sync_mappings(), and
* vmalloc_sync_unmappings()
Most call-sites to vmalloc_sync_all() only care about new mappings being
synchronized. The only exception is the new call-site added in the
above mentioned commit.
Shile Zhang directed us to a report of an 80% regression in reaim
throughput.
Fixes: 3f8fd02b1b ("mm/vmalloc: Sync unmappings in __purge_vmap_area_lazy()")
Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: Shile Zhang <shile.zhang@linux.alibaba.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Borislav Petkov <bp@suse.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [GHES]
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20191009124418.8286-1-joro@8bytes.org
Link: https://lists.01.org/hyperkitty/list/lkp@lists.01.org/thread/4D3JPPHBNOSPFK2KEPC6KGKS6J25AIDB/
Link: http://lkml.kernel.org/r/20191113095530.228959-1-shile.zhang@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, rcu_barrier() ignores offline CPUs, However, it is possible
for an offline no-CBs CPU to have callbacks queued, and rcu_barrier()
must wait for those callbacks. This commit therefore makes rcu_barrier()
directly invoke the rcu_barrier_func() with interrupts disabled for such
CPUs. This requires passing the CPU number into this function so that
it can entrain the rcu_barrier() callback onto the correct CPU's callback
list, given that the code must instead execute on the current CPU.
While in the area, this commit fixes a bug where the first CPU's callback
might have been invoked before rcu_segcblist_entrain() returned, which
would also result in an early wakeup.
Fixes: 5d6742b377 ("rcu/nocb: Use rcu_segcblist for no-CBs CPUs")
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Apply optimization feedback from Boqun Feng. ]
Cc: <stable@vger.kernel.org> # 5.5.x
The rcu_state structure's gp_seq field is only to be modified by the RCU
grace-period kthread, which is single-threaded. This commit therefore
enlists KCSAN's help in enforcing this restriction.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The handling of notify->work did not properly maintain notify->kref in two
cases:
1) where the work was already scheduled, another irq_set_affinity_locked()
would get the ref and (no-op-ly) schedule the work. Thus when
irq_affinity_notify() ran, it would drop the original ref but not the
additional one.
2) when cancelling the (old) work in irq_set_affinity_notifier(), if there
was outstanding work a ref had been got for it but was never put.
Fix both by checking the return values of the work handling functions
(schedule_work() for (1) and cancel_work_sync() for (2)) and put the
extra ref if the return value indicates preexisting work.
Fixes: cd7eab44e9 ("genirq: Add IRQ affinity notifiers")
Fixes: 59c39840f5 ("genirq: Prevent use-after-free and work list corruption")
Signed-off-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Ben Hutchings <ben@decadent.org.uk>
Link: https://lkml.kernel.org/r/24f5983f-2ab5-e83a-44ee-a45b5f9300f5@solarflare.com
Continue what commit:
d820ac4c2f ("locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]")
started, rename these to avoid confusing them with tracepoints.
git grep -l "trace_\(soft\|hard\)\(irq_context\|irqs_enabled\)" | while read file;
do
sed -ie 's/trace_\(soft\|hard\)\(irq_context\|irqs_enabled\)/lockdep_\1\2/g' $file;
done
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200320115859.178626842@infradead.org
Continue what commit:
d820ac4c2f ("locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]")
started, rename these to avoid confusing them with tracepoints.
git grep -l "trace_softirqs_\(on\|off\)" | while read file;
do
sed -ie 's/trace_softirqs_\(on\|off\)/lockdep_softirqs_\1/g' $file;
done
Reported-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200320115859.119434738@infradead.org
Continue what commit:
d820ac4c2f ("locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]")
started, rename these to avoid confusing them with tracepoints.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200320115859.060481361@infradead.org
Splitting run_posix_cpu_timers() into two parts is work in progress which
is stuck on other entry code related problems. The heavy lifting which
involves locking of sighand lock will be moved into task context so the
necessary execution time is burdened on the task and not on interrupt
context.
Until this work completes lockdep with the spinlock nesting rules enabled
would emit warnings for this known context.
Prevent it by setting "->irq_config = 1" for the invocation of
run_posix_cpu_timers() so lockdep does not complain when sighand lock is
acquried. This will be removed once the split is completed.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.751182723@linutronix.de
Mark irq_work items with IRQ_WORK_HARD_IRQ which should be invoked in
hardirq context even on PREEMPT_RT. IRQ_WORK without this flag will be
invoked in softirq context on PREEMPT_RT.
Set ->irq_config to 1 for the IRQ_WORK items which are invoked in softirq
context so lockdep knows that these can safely acquire a spinlock_t.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.643576700@linutronix.de
Set current->irq_config = 1 for hrtimers which are not marked to expire in
hard interrupt context during hrtimer_init(). These timers will expire in
softirq context on PREEMPT_RT.
Setting this allows lockdep to differentiate these timers. If a timer is
marked to expire in hard interrupt context then the timer callback is not
supposed to acquire a regular spinlock instead of a raw_spinlock in the
expiry callback.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.534508206@linutronix.de
Extend lockdep to validate lock wait-type context.
The current wait-types are:
LD_WAIT_FREE, /* wait free, rcu etc.. */
LD_WAIT_SPIN, /* spin loops, raw_spinlock_t etc.. */
LD_WAIT_CONFIG, /* CONFIG_PREEMPT_LOCK, spinlock_t etc.. */
LD_WAIT_SLEEP, /* sleeping locks, mutex_t etc.. */
Where lockdep validates that the current lock (the one being acquired)
fits in the current wait-context (as generated by the held stack).
This ensures that there is no attempt to acquire mutexes while holding
spinlocks, to acquire spinlocks while holding raw_spinlocks and so on. In
other words, its a more fancy might_sleep().
Obviously RCU made the entire ordeal more complex than a simple single
value test because RCU can be acquired in (pretty much) any context and
while it presents a context to nested locks it is not the same as it
got acquired in.
Therefore its necessary to split the wait_type into two values, one
representing the acquire (outer) and one representing the nested context
(inner). For most 'normal' locks these two are the same.
[ To make static initialization easier we have the rule that:
.outer == INV means .outer == .inner; because INV == 0. ]
It further means that its required to find the minimal .inner of the held
stack to compare against the outer of the new lock; because while 'normal'
RCU presents a CONFIG type to nested locks, if it is taken while already
holding a SPIN type it obviously doesn't relax the rules.
Below is an example output generated by the trivial test code:
raw_spin_lock(&foo);
spin_lock(&bar);
spin_unlock(&bar);
raw_spin_unlock(&foo);
[ BUG: Invalid wait context ]
-----------------------------
swapper/0/1 is trying to lock:
ffffc90000013f20 (&bar){....}-{3:3}, at: kernel_init+0xdb/0x187
other info that might help us debug this:
1 lock held by swapper/0/1:
#0: ffffc90000013ee0 (&foo){+.+.}-{2:2}, at: kernel_init+0xd1/0x187
The way to read it is to look at the new -{n,m} part in the lock
description; -{3:3} for the attempted lock, and try and match that up to
the held locks, which in this case is the one: -{2,2}.
This tells that the acquiring lock requires a more relaxed environment than
presented by the lock stack.
Currently only the normal locks and RCU are converted, the rest of the
lockdep users defaults to .inner = INV which is ignored. More conversions
can be done when desired.
The check for spinlock_t nesting is not enabled by default. It's a separate
config option for now as there are known problems which are currently
addressed. The config option allows to identify these problems and to
verify that the solutions found are indeed solving them.
The config switch will be removed and the checks will permanently enabled
once the vast majority of issues has been addressed.
[ bigeasy: Move LD_WAIT_FREE,… out of CONFIG_LOCKDEP to avoid compile
failure with CONFIG_DEBUG_SPINLOCK + !CONFIG_LOCKDEP]
[ tglx: Add the config option ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.427089655@linutronix.de
completion uses a wait_queue_head_t to enqueue waiters.
wait_queue_head_t contains a spinlock_t to protect the list of waiters
which excludes it from being used in truly atomic context on a PREEMPT_RT
enabled kernel.
The spinlock in the wait queue head cannot be replaced by a raw_spinlock
because:
- wait queues can have custom wakeup callbacks, which acquire other
spinlock_t locks and have potentially long execution times
- wake_up() walks an unbounded number of list entries during the wake up
and may wake an unbounded number of waiters.
For simplicity and performance reasons complete() should be usable on
PREEMPT_RT enabled kernels.
completions do not use custom wakeup callbacks and are usually single
waiter, except for a few corner cases.
Replace the wait queue in the completion with a simple wait queue (swait),
which uses a raw_spinlock_t for protecting the waiter list and therefore is
safe to use inside truly atomic regions on PREEMPT_RT.
There is no semantical or functional change:
- completions use the exclusive wait mode which is what swait provides
- complete() wakes one exclusive waiter
- complete_all() wakes all waiters while holding the lock which protects
the wait queue against newly incoming waiters. The conversion to swait
preserves this behaviour.
complete_all() might cause unbound latencies with a large number of waiters
being woken at once, but most complete_all() usage sites are either in
testing or initialization code or have only a really small number of
concurrent waiters which for now does not cause a latency problem. Keep it
simple for now.
The fixup of the warning check in the USB gadget driver is just a straight
forward conversion of the lockless waiter check from one waitqueue type to
the other.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lkml.kernel.org/r/20200321113242.317954042@linutronix.de
As a preparation to use simple wait queues for completions:
- Provide swake_up_all_locked() to support complete_all()
- Make __prepare_to_swait() public available
This is done to enable the usage of complete() within truly atomic contexts
on a PREEMPT_RT enabled kernel.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.228481202@linutronix.de
seqlock consists of a sequence counter and a spinlock_t which is used to
serialize the writers. spinlock_t is substituted by a "sleeping" spinlock
on PREEMPT_RT enabled kernels which breaks the usage in the timekeeping
code as the writers are executed in hard interrupt and therefore
non-preemptible context even on PREEMPT_RT.
The spinlock in seqlock cannot be unconditionally replaced by a
raw_spinlock_t as many seqlock users have nesting spinlock sections or
other code which is not suitable to run in truly atomic context on RT.
Instead of providing a raw_seqlock API for a single use case, open code the
seqlock for the jiffies use case and implement it with a raw_spinlock_t and
a sequence counter.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113242.120587764@linutronix.de
Extend rcuwait_wait_event() with a state variable so that it is not
restricted to UNINTERRUPTIBLE waits.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200321113241.824030968@linutronix.de
Previously the system would lock up if ftrace was enabled together with
KCSAN. This is due to recursion on reporting if the tracer code is
instrumented with KCSAN.
To avoid this for all types of tracing, disable KCSAN instrumentation
for all of kernel/trace.
Furthermore, since KCSAN relies on udelay() to introduce delay, we have
to disable ftrace for udelay() (currently done for x86) in case KCSAN is
used together with lockdep and ftrace. The reason is that it may corrupt
lockdep IRQ flags tracing state due to a peculiar case of recursion
(details in Makefile comment).
Reported-by: Qian Cai <cai@lca.pw>
Tested-by: Qian Cai <cai@lca.pw>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This introduces ASSERT_EXCLUSIVE_BITS(var, mask).
ASSERT_EXCLUSIVE_BITS(var, mask) will cause KCSAN to assume that the
following access is safe w.r.t. data races (however, please see the
docbook comment for disclaimer here).
For more context on why this was considered necessary, please see:
http://lkml.kernel.org/r/1580995070-25139-1-git-send-email-cai@lca.pw
In particular, before this patch, data races between reads (that use
@mask bits of an access that should not be modified concurrently) and
writes (that change ~@mask bits not used by the readers) would have been
annotated with "data_race()" (or "READ_ONCE()"). However, doing so would
then hide real problems: we would no longer be able to detect harmful
races between reads to @mask bits and writes to @mask bits.
Therefore, by using ASSERT_EXCLUSIVE_BITS(var, mask), we accomplish:
1. Avoid proliferation of specific macros at the call sites: by
including a single mask in the argument list, we can use the same
macro in a wide variety of call sites, regardless of how and which
bits in a field each call site actually accesses.
2. The existing code does not need to be modified (although READ_ONCE()
may still be advisable if we cannot prove that the data race is
always safe).
3. We catch bugs where the exclusive bits are modified concurrently.
4. We document properties of the current code.
Acked-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Qian Cai <cai@lca.pw>
When setting up an access mask with kcsan_set_access_mask(), KCSAN will
only report races if concurrent changes to bits set in access_mask are
observed. Conveying access_mask via a separate call avoids introducing
overhead in the common-case fast-path.
Acked-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduces kcsan_value_change type, which explicitly points out if we
either observed a value-change (TRUE), or we could not observe one but
cannot rule out a value-change happened (MAYBE). The MAYBE state can
either be reported or not, depending on configuration preferences.
A follow-up patch introduces the FALSE state, which should never be
reported.
No functional change intended.
Acked-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If there are at least 4 threads racing on the same address, it can
happen that one of the readers may observe another matching reader in
other_info. To avoid locking up, we have to consume 'other_info'
regardless, but skip the report. See the added comment for more details.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This adds early_boot, udelay_{task,interrupt}, and skip_watch as module
params. The latter parameters are useful to modify at runtime to tune
KCSAN's performance on new systems. This will also permit auto-tuning
these parameters to maximize overall system performance and KCSAN's race
detection ability.
None of the parameters are used in the fast-path and referring to them
via static variables instead of CONFIG constants will not affect
performance.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Qian Cai <cai@lca.pw>
Add 'test=<iters>' option to KCSAN's debugfs interface to invoke KCSAN
checks on a dummy variable. By writing 'test=<iters>' to the debugfs
file from multiple tasks, we can generate real conflicts, and trigger
data race reports.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The KCSAN_ACCESS_ASSERT access type may be used to introduce dummy reads
and writes to assert certain properties of concurrent code, where bugs
could not be detected as normal data races.
For example, a variable that is only meant to be written by a single
CPU, but may be read (without locking) by other CPUs must still be
marked properly to avoid data races. However, concurrent writes,
regardless if WRITE_ONCE() or not, would be a bug. Using
kcsan_check_access(&x, sizeof(x), KCSAN_ACCESS_ASSERT) would allow
catching such bugs.
To support KCSAN_ACCESS_ASSERT the following notable changes were made:
* If an access is of type KCSAN_ASSERT_ACCESS, disable various filters
that only apply to data races, so that all races that KCSAN observes are
reported.
* Bug reports that involve an ASSERT access type will be reported as
"KCSAN: assert: race in ..." instead of "data-race"; this will help
more easily distinguish them.
* Update a few comments to just mention 'races' where we do not always
mean pure data races.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Instrumentation of arbitrary memory-copy functions, such as user-copies,
may be called with size of 0, which could lead to false positives.
To avoid this, add a comparison in check_access() for size==0, which
will be optimized out for constant sized instrumentation
(__tsan_{read,write}N), and therefore not affect the common-case
fast-path.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This adds option KCSAN_ASSUME_PLAIN_WRITES_ATOMIC. If enabled, plain
aligned writes up to word size are assumed to be atomic, and also not
subject to other unsafe compiler optimizations resulting in data races.
This option has been enabled by default to reflect current kernel-wide
preferences.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Even with KCSAN_REPORT_VALUE_CHANGE_ONLY, KCSAN still reports data
races between reads and watchpointed writes, even if the writes wrote
values already present. This commit causes KCSAN to unconditionally
skip reporting in this case.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We must avoid any recursion into lockdep if KCSAN is enabled on utilities
used by lockdep. One manifestation of this is corruption of lockdep's
IRQ trace state (if TRACE_IRQFLAGS), resulting in spurious warnings
(see below). This commit fixes this by:
1. Using raw_local_irq{save,restore} in kcsan_setup_watchpoint().
2. Disabling lockdep in kcsan_report().
Tested with:
CONFIG_LOCKDEP=y
CONFIG_DEBUG_LOCKDEP=y
CONFIG_TRACE_IRQFLAGS=y
This fix eliminates spurious warnings such as the following one:
WARNING: CPU: 0 PID: 2 at kernel/locking/lockdep.c:4406 check_flags.part.0+0x101/0x220
Modules linked in:
CPU: 0 PID: 2 Comm: kthreadd Not tainted 5.5.0-rc1+ #11
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
RIP: 0010:check_flags.part.0+0x101/0x220
<snip>
Call Trace:
lock_is_held_type+0x69/0x150
freezer_fork+0x20b/0x370
cgroup_post_fork+0x2c9/0x5c0
copy_process+0x2675/0x3b40
_do_fork+0xbe/0xa30
? _raw_spin_unlock_irqrestore+0x40/0x50
? match_held_lock+0x56/0x250
? kthread_park+0xf0/0xf0
kernel_thread+0xa6/0xd0
? kthread_park+0xf0/0xf0
kthreadd+0x321/0x3d0
? kthread_create_on_cpu+0x130/0x130
ret_from_fork+0x3a/0x50
irq event stamp: 64
hardirqs last enabled at (63): [<ffffffff9a7995d0>] _raw_spin_unlock_irqrestore+0x40/0x50
hardirqs last disabled at (64): [<ffffffff992a96d2>] kcsan_setup_watchpoint+0x92/0x460
softirqs last enabled at (32): [<ffffffff990489b8>] fpu__copy+0xe8/0x470
softirqs last disabled at (30): [<ffffffff99048939>] fpu__copy+0x69/0x470
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Alexander Potapenko <glider@google.com>
Tested-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
KCSAN data-race reports can occur quite frequently, so much so as
to render the system useless. This commit therefore adds support for
time-based rate-limiting KCSAN reports, with the time interval specified
by a new KCSAN_REPORT_ONCE_IN_MS Kconfig option. The default is 3000
milliseconds, also known as three seconds.
Because KCSAN must detect data races in allocators and in other contexts
where use of allocation is ill-advised, a fixed-size array is used to
buffer reports during each reporting interval. To reduce the number of
reports lost due to array overflow, this commit stores only one instance
of duplicate reports, which has the benefit of further reducing KCSAN's
console output rate.
Reported-by: Qian Cai <cai@lca.pw>
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit adds access-type information to KCSAN's reports as follows:
"read", "read (marked)", "write", and "write (marked)".
Suggested-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Prefer __always_inline for fast-path functions that are called outside
of user_access_save, to avoid generating UACCESS warnings when
optimizing for size (CC_OPTIMIZE_FOR_SIZE). It will also avoid future
surprises with compiler versions that change the inlining heuristic even
when optimizing for performance.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/58708908-84a0-0a81-a836-ad97e33dbb62@infradead.org
Trying to initialize a structure with "= {};" will not always clean out
all padding locations in a structure. So be explicit and call memset to
initialize everything for a number of bpf information structures that
are then copied from userspace, sometimes from smaller memory locations
than the size of the structure.
Reported-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200320162258.GA794295@kroah.com
For the bpf syscall, we are relying on the compiler to properly zero out
the bpf_attr union that we copy userspace data into. Unfortunately that
doesn't always work properly, padding and other oddities might not be
correctly zeroed, and in some tests odd things have been found when the
stack is pre-initialized to other values.
Fix this by explicitly memsetting the structure to 0 before using it.
Reported-by: Maciej Żenczykowski <maze@google.com>
Reported-by: John Stultz <john.stultz@linaro.org>
Reported-by: Alexander Potapenko <glider@google.com>
Reported-by: Alistair Delva <adelva@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://android-review.googlesource.com/c/kernel/common/+/1235490
Link: https://lore.kernel.org/bpf/20200320094813.GA421650@kroah.com
nmi_enter() does lockdep_off() and hence lockdep ignores everything.
And NMI context makes it impossible to do full IN-NMI tracking like we
do IN-HARDIRQ, that could result in graph_lock recursion.
However, since look_up_lock_class() is lockless, we can find the class
of a lock that has prior use and detect IN-NMI after USED, just not
USED after IN-NMI.
NOTE: By shifting the lockdep_off() recursion count to bit-16, we can
easily differentiate between actual recursion and off.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lkml.kernel.org/r/20200221134215.090538203@infradead.org
There were two patterns for lockdep_recursion:
Pattern-A:
if (current->lockdep_recursion)
return
current->lockdep_recursion = 1;
/* do stuff */
current->lockdep_recursion = 0;
Pattern-B:
current->lockdep_recursion++;
/* do stuff */
current->lockdep_recursion--;
But a third pattern has emerged:
Pattern-C:
current->lockdep_recursion = 1;
/* do stuff */
current->lockdep_recursion = 0;
And while this isn't broken per-se, it is highly dangerous because it
doesn't nest properly.
Get rid of all Pattern-C instances and shore up Pattern-A with a
warning.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200313093325.GW12561@hirez.programming.kicks-ass.net
Qian Cai reported a bug when PROVE_RCU_LIST=y, and read on /proc/lockdep
triggered a warning:
[ ] DEBUG_LOCKS_WARN_ON(current->hardirqs_enabled)
...
[ ] Call Trace:
[ ] lock_is_held_type+0x5d/0x150
[ ] ? rcu_lockdep_current_cpu_online+0x64/0x80
[ ] rcu_read_lock_any_held+0xac/0x100
[ ] ? rcu_read_lock_held+0xc0/0xc0
[ ] ? __slab_free+0x421/0x540
[ ] ? kasan_kmalloc+0x9/0x10
[ ] ? __kmalloc_node+0x1d7/0x320
[ ] ? kvmalloc_node+0x6f/0x80
[ ] __bfs+0x28a/0x3c0
[ ] ? class_equal+0x30/0x30
[ ] lockdep_count_forward_deps+0x11a/0x1a0
The warning got triggered because lockdep_count_forward_deps() call
__bfs() without current->lockdep_recursion being set, as a result
a lockdep internal function (__bfs()) is checked by lockdep, which is
unexpected, and the inconsistency between the irq-off state and the
state traced by lockdep caused the warning.
Apart from this warning, lockdep internal functions like __bfs() should
always be protected by current->lockdep_recursion to avoid potential
deadlocks and data inconsistency, therefore add the
current->lockdep_recursion on-and-off section to protect __bfs() in both
lockdep_count_forward_deps() and lockdep_count_backward_deps()
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200312151258.128036-1-boqun.feng@gmail.com
This NULL check is reversed so it leads to a Smatch warning and
presumably a NULL dereference.
kernel/events/core.c:1598 perf_event_groups_less()
error: we previously assumed 'right->cgrp->css.cgroup' could be null
(see line 1590)
Fixes: 95ed6c707f ("perf/cgroup: Order events in RB tree by cgroup id")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200312105637.GA8960@mwanda
Kan and Andi reported that we fail to kill rotation when the flexible
events go empty, but the context does not. XXX moar
Fixes: fd7d55172d ("perf/cgroups: Don't rotate events for cgroups unnecessarily")
Reported-by: Andi Kleen <ak@linux.intel.com>
Reported-by: Kan Liang <kan.liang@linux.intel.com>
Tested-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200305123851.GX2596@hirez.programming.kicks-ass.net
In update_sg_wakeup_stats(), the comment says:
Computing avg_load makes sense only when group is fully
busy or overloaded.
But, the code below this comment does not check like this.
From reading the code about avg_load in other functions, I
confirm that avg_load should be calculated in fully busy or
overloaded case. The comment is correct and the checking
condition is wrong. So, change that condition.
Fixes: 57abff067a ("sched/fair: Rework find_idlest_group()")
Signed-off-by: Tao Zhou <ouwen210@hotmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Mel Gorman <mgorman@suse.de>
Link: https://lkml.kernel.org/r/Message-ID:
If we failed to find a fitting CPU, in cpupri_find(), we only fallback
to the level we found a hit at.
But Steve suggested to fallback to a second full scan instead as this
could be a better effort.
https://lore.kernel.org/lkml/20200304135404.146c56eb@gandalf.local.home/
We trigger the 2nd search unconditionally since the argument about
triggering a full search is that the recorded fall back level might have
become empty by then. Which means storing any data about what happened
would be meaningless and stale.
I had a humble try at timing it and it seemed okay for the small 6 CPUs
system I was running on
https://lore.kernel.org/lkml/20200305124324.42x6ehjxbnjkklnh@e107158-lin.cambridge.arm.com/
On large system this second full scan could be expensive. But there are
no users outside capacity awareness for this fitness function at the
moment. Heterogeneous systems tend to be small with 8cores in total.
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20200310142219.syxzn5ljpdxqtbgx@e107158-lin.cambridge.arm.com
when we create a kthread with ktrhead_create_on_cpu(),the child thread
entry is ktread.c:ktrhead() which will be preempted by the parent after
call complete(done) while schedule() is not called yet,then the parent
will call wait_task_inactive(child) but the child is still on the runqueue,
so the parent will schedule_hrtimeout() for 1 jiffy,it will waste a lot of
time,especially on startup.
parent child
ktrhead_create_on_cpu()
wait_fo_completion(&done) -----> ktread.c:ktrhead()
|----- complete(done);--wakeup and preempted by parent
kthread_bind() <------------| |-> schedule();--dequeue here
wait_task_inactive(child) |
schedule_hrtimeout(1 jiffy) -|
So we hope the child just wakeup parent but not preempted by parent, and the
child is going to call schedule() soon,then the parent will not call
schedule_hrtimeout(1 jiffy) as the child is already dequeue.
The same issue for ktrhead_park()&&kthread_parkme().
This patch can save 120ms on rk312x startup with CONFIG_HZ=300.
Signed-off-by: Liang Chen <cl@rock-chips.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20200306070133.18335-2-cl@rock-chips.com
During load_balancing, a group with spare capacity will try to pull some
utilizations from an overloaded group. In such case, the load balance
looks for the runqueue with the highest utilization. Nevertheless, it
should also ensure that there are some pending tasks to pull otherwise
the load balance will fail to pull a task and the spread of the load will
be delayed.
This situation is quite transient but it's possible to highlight the
effect with a short run of sysbench test so the time to spread task impacts
the global result significantly.
Below are the average results for 15 iterations on an arm64 octo core:
sysbench --test=cpu --num-threads=8 --max-requests=1000 run
tip/sched/core +patchset
total time: 172ms 158ms
per-request statistics:
avg: 1.337ms 1.244ms
max: 21.191ms 10.753ms
The average max doesn't fully reflect the wide spread of the value which
ranges from 1.350ms to more than 41ms for the tip/sched/core and from
1.350ms to 21ms with the patch.
Other factors like waiting for an idle load balance or cache hotness
can delay the spreading of the tasks which explains why we can still
have up to 21ms with the patch.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200312165429.990-1-vincent.guittot@linaro.org
During our testing, we found a case that shares no longer
working correctly, the cgroup topology is like:
/sys/fs/cgroup/cpu/A (shares=102400)
/sys/fs/cgroup/cpu/A/B (shares=2)
/sys/fs/cgroup/cpu/A/B/C (shares=1024)
/sys/fs/cgroup/cpu/D (shares=1024)
/sys/fs/cgroup/cpu/D/E (shares=1024)
/sys/fs/cgroup/cpu/D/E/F (shares=1024)
The same benchmark is running in group C & F, no other tasks are
running, the benchmark is capable to consumed all the CPUs.
We suppose the group C will win more CPU resources since it could
enjoy all the shares of group A, but it's F who wins much more.
The reason is because we have group B with shares as 2, since
A->cfs_rq.load.weight == B->se.load.weight == B->shares/nr_cpus,
so A->cfs_rq.load.weight become very small.
And in calc_group_shares() we calculate shares as:
load = max(scale_load_down(cfs_rq->load.weight), cfs_rq->avg.load_avg);
shares = (tg_shares * load) / tg_weight;
Since the 'cfs_rq->load.weight' is too small, the load become 0
after scale down, although 'tg_shares' is 102400, shares of the se
which stand for group A on root cfs_rq become 2.
While the se of D on root cfs_rq is far more bigger than 2, so it
wins the battle.
Thus when scale_load_down() scale real weight down to 0, it's no
longer telling the real story, the caller will have the wrong
information and the calculation will be buggy.
This patch add check in scale_load_down(), so the real weight will
be >= MIN_SHARES after scale, after applied the group C wins as
expected.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Michael Wang <yun.wang@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/38e8e212-59a1-64b2-b247-b6d0b52d8dc1@linux.alibaba.com
The task->flags is a 32-bits flag, in which 31 bits have already been
consumed. So it is hardly to introduce other new per process flag.
Currently there're still enough spaces in the bit-field section of
task_struct, so we can define the memstall state as a single bit in
task_struct instead.
This patch also removes an out-of-date comment pointed by Matthew.
Suggested-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Yafang Shao <laoar.shao@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/1584408485-1921-1-git-send-email-laoar.shao@gmail.com
When switching tasks running on a CPU, the psi state of a cgroup
containing both of these tasks does not change. Right now, we don't
exploit that, and can perform many unnecessary state changes in nested
hierarchies, especially when most activity comes from one leaf cgroup.
This patch implements an optimization where we only update cgroups
whose state actually changes during a task switch. These are all
cgroups that contain one task but not the other, up to the first
shared ancestor. When both tasks are in the same group, we don't need
to update anything at all.
We can identify the first shared ancestor by walking the groups of the
incoming task until we see TSK_ONCPU set on the local CPU; that's the
first group that also contains the outgoing task.
The new psi_task_switch() is similar to psi_task_change(). To allow
code reuse, move the task flag maintenance code into a new function
and the poll/avg worker wakeups into the shared psi_group_change().
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200316191333.115523-3-hannes@cmpxchg.org
For simplicity, cpu pressure is defined as having more than one
runnable task on a given CPU. This works on the system-level, but it
has limitations in a cgrouped reality: When cpu.max is in use, it
doesn't capture the time in which a task is not executing on the CPU
due to throttling. Likewise, it doesn't capture the time in which a
competing cgroup is occupying the CPU - meaning it only reflects
cgroup-internal competitive pressure, not outside pressure.
Enable tracking of currently executing tasks, and then change the
definition of cpu pressure in a cgroup from
NR_RUNNING > 1
to
NR_RUNNING > ON_CPU
which will capture the effects of cpu.max as well as competition from
outside the cgroup.
After this patch, a cgroup running `stress -c 1` with a cpu.max
setting of 5000 10000 shows ~50% continuous CPU pressure.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200316191333.115523-2-hannes@cmpxchg.org
Currently, when updating the affinity of tasks via either cpusets.cpus,
or, sched_setaffinity(); tasks not currently running within the newly
specified mask will be arbitrarily assigned to the first CPU within the
mask.
This (particularly in the case that we are restricting masks) can
result in many tasks being assigned to the first CPUs of their new
masks.
This:
1) Can induce scheduling delays while the load-balancer has a chance to
spread them between their new CPUs.
2) Can antogonize a poor load-balancer behavior where it has a
difficult time recognizing that a cross-socket imbalance has been
forced by an affinity mask.
This change adds a new cpumask interface to allow iterated calls to
distribute within the intersection of the provided masks.
The cases that this mainly affects are:
- modifying cpuset.cpus
- when tasks join a cpuset
- when modifying a task's affinity via sched_setaffinity(2)
Signed-off-by: Paul Turner <pjt@google.com>
Signed-off-by: Josh Don <joshdon@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Tested-by: Qais Yousef <qais.yousef@arm.com>
Link: https://lkml.kernel.org/r/20200311010113.136465-1-joshdon@google.com
When a cfs rq is throttled, the latter and its child are removed from the
leaf list but their nr_running is not changed which includes staying higher
than 1. When a task is enqueued in this throttled branch, the cfs rqs must
be added back in order to ensure correct ordering in the list but this can
only happens if nr_running == 1.
When cfs bandwidth is used, we call unconditionnaly list_add_leaf_cfs_rq()
when enqueuing an entity to make sure that the complete branch will be
added.
Similarly unthrottle_cfs_rq() can stop adding cfs in the list when a parent
is throttled. Iterate the remaining entity to ensure that the complete
branch will be added in the list.
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Christian Borntraeger <borntraeger@de.ibm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: stable@vger.kernel.org
Cc: stable@vger.kernel.org #v5.1+
Link: https://lkml.kernel.org/r/20200306135257.25044-1-vincent.guittot@linaro.org
As it is fine to perform several "peeks" of event data in the ring buffer
via the iterator before moving it forward, do not re-read the event, just
return what was read before. Otherwise, it can cause inconsistent results,
especially when testing multiple CPU buffers to interleave them.
Link: http://lkml.kernel.org/r/20200317213416.592032170@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As the iterator will be reading a live buffer, and if the event being read
is on a page that a writer crosses, it will fail and try again, the
condition in rb_iter_peek() that only allows a retry to happen three times
is no longer valid. Allow rb_iter_peek() to retry more than three times
without killing the ring buffer, but only if rb_iter_head_event() had failed
at least once.
Link: http://lkml.kernel.org/r/20200317213416.452888193@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Have the ring_buffer_iter structure have a place to store an event, such
that it can not be overwritten by a writer, and load it in such a way via
rb_iter_head_event() that it will return NULL and reset the iter to the
start of the current page if a writer updated the page.
Link: http://lkml.kernel.org/r/20200317213416.306959216@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Have the ring_buffer_iter structure contain a page_stamp, such that it can
be used to see if the writer entered the page the iterator is on. When going
to a new page, the iterator will record the time stamp of that page. When
reading events, it can copy the event to an internal buffer on the iterator
(to be implemented later), then check the page's time stamp with its own to
see if the writer entered the page. If so, it will need to try to read the
event again.
Link: http://lkml.kernel.org/r/20200317213416.163549674@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When the ring buffer was first created, the iterator followed the normal
producer/consumer operations where it had both a peek() operation, that just
returned the event at the current location, and a read(), that would return
the event at the current location and also increment the iterator such that
the next peek() or read() will return the next event.
The only use of the ring_buffer_read() is currently to move the iterator to
the next location and nothing now actually reads the event it returns.
Rename this function to its actual use case to ring_buffer_iter_advance(),
which also adds the "iter" part to the name, which is more meaningful. As
the timestamp returned by ring_buffer_read() was never used, there's no
reason that this new version should bother having returning it. It will also
become a void function.
Link: http://lkml.kernel.org/r/20200317213416.018928618@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
It was complained about that when the trace file is read, that the tracing
is disabled, as the iterator expects writing to the buffer it reads is not
updated. Several steps are needed to make the iterator handle a writer,
by testing if things have changed as it reads.
This step is to make ring_buffer_empty() expect the buffer to be changing.
Note if the current location of the iterator is overwritten, then it will
return false as new data is being added. Note, that this means that data
will be skipped.
Link: http://lkml.kernel.org/r/20200317213415.870741809@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In order to have the iterator read the buffer even when it's still updating,
it requires that the ring buffer iterator saves each event in a separate
location outside the ring buffer such that its use is immutable.
There's one use case that saves off the event returned from the ring buffer
interator and calls it again to look at the next event, before going back to
use the first event. As the ring buffer iterator will only have a single
copy, this use case will no longer be supported.
Instead, have the one use case create its own buffer to store the first
event when looking at the next event. This way, when looking at the first
event again, it wont be corrupted by the second read.
Link: http://lkml.kernel.org/r/20200317213415.722539921@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Clang warns:
../kernel/trace/trace.c:9335:33: warning: array comparison always
evaluates to true [-Wtautological-compare]
if (__stop___trace_bprintk_fmt != __start___trace_bprintk_fmt)
^
1 warning generated.
These are not true arrays, they are linker defined symbols, which are
just addresses. Using the address of operator silences the warning and
does not change the runtime result of the check (tested with some print
statements compiled in with clang + ld.lld and gcc + ld.bfd in QEMU).
Link: http://lkml.kernel.org/r/20200220051011.26113-1-natechancellor@gmail.com
Link: https://github.com/ClangBuiltLinux/linux/issues/893
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This reverts commit d441dceb5d due to
boot failures.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Simplify gen_btf logic to make it work with llvm-objcopy. The existing
'file format' and 'architecture' parsing logic is brittle and does not
work with llvm-objcopy/llvm-objdump.
'file format' output of llvm-objdump>=11 will match GNU objdump, but
'architecture' (bfdarch) may not.
.BTF in .tmp_vmlinux.btf is non-SHF_ALLOC. Add the SHF_ALLOC flag
because it is part of vmlinux image used for introspection. C code
can reference the section via linker script defined __start_BTF and
__stop_BTF. This fixes a small problem that previous .BTF had the
SHF_WRITE flag (objcopy -I binary -O elf* synthesized .data).
Additionally, `objcopy -I binary` synthesized symbols
_binary__btf_vmlinux_bin_start and _binary__btf_vmlinux_bin_stop (not
used elsewhere) are replaced with more commonplace __start_BTF and
__stop_BTF.
Add 2>/dev/null because GNU objcopy (but not llvm-objcopy) warns
"empty loadable segment detected at vaddr=0xffffffff81000000, is this intentional?"
We use a dd command to change the e_type field in the ELF header from
ET_EXEC to ET_REL so that lld will accept .btf.vmlinux.bin.o. Accepting
ET_EXEC as an input file is an extremely rare GNU ld feature that lld
does not intend to support, because this is error-prone.
The output section description .BTF in include/asm-generic/vmlinux.lds.h
avoids potential subtle orphan section placement issues and suppresses
--orphan-handling=warn warnings.
Fixes: df786c9b94 ("bpf: Force .BTF section start to zero when dumping from vmlinux")
Fixes: cb0cc635c7 ("powerpc: Include .BTF section")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Fangrui Song <maskray@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: Stanislav Fomichev <sdf@google.com>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Reviewed-by: Stanislav Fomichev <sdf@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Link: https://github.com/ClangBuiltLinux/linux/issues/871
Link: https://lore.kernel.org/bpf/20200318222746.173648-1-maskray@google.com
To minimize latency, PREEMPT_RT kernels expires hrtimers in preemptible
softirq context by default. This can be overriden by marking the timer's
expiry with HRTIMER_MODE_HARD.
sched_clock_timer is missing this annotation: if its callback is preempted
and the duration of the preemption exceeds the wrap around time of the
underlying clocksource, sched clock will get out of sync.
Mark the sched_clock_timer for expiry in hard interrupt context.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200309181529.26558-1-a.darwish@linutronix.de
HWRNG_MINOR and RNG_MISCDEV_MINOR are duplicate definitions, use
unified HWRNG_MINOR instead and moved into miscdevice.h
ANSLCD_MINOR and LCD_MINOR are duplicate definitions, use unified
LCD_MINOR instead and moved into miscdevice.h
MISCDEV_MINOR is renamed to PXA3XX_GCU_MINOR and moved into
miscdevice.h
Other definitions are just moved without any change.
Link: https://lore.kernel.org/lkml/20200120221323.GJ15860@mit.edu/t/
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Build-tested-by: Willy TARREAU <wtarreau@haproxy.com>
Build-tested-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@gmail.com>
Acked-by: Miguel Ojeda <miguel.ojeda.sandonis@gmail.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Herbert Xu <herbert@gondor.apana.org.au>
Link: https://lore.kernel.org/r/20200311071654.335-2-zhenzhong.duan@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The bpf_struct_ops tcp-cc name should be sanitized in order to
avoid problematic chars (e.g. whitespaces).
This patch reuses the bpf_obj_name_cpy() for accepting the same set
of characters in order to keep a consistent bpf programming experience.
A "size" param is added. Also, the strlen is returned on success so
that the caller (like the bpf_tcp_ca here) can error out on empty name.
The existing callers of the bpf_obj_name_cpy() only need to change the
testing statement to "if (err < 0)". For all these existing callers,
the err will be overwritten later, so no extra change is needed
for the new strlen return value.
v3:
- reverse xmas tree style
v2:
- Save the orig_src to avoid "end - size" (Andrii)
Fixes: 0baf26b0fc ("bpf: tcp: Support tcp_congestion_ops in bpf")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200314010209.1131542-1-kafai@fb.com
We need the console patches in here as well for futher work from Andy.
* 'for-5.7-console-exit' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
console: Introduce ->exit() callback
console: Don't notify user space when unregister non-listed console
console: Avoid positive return code from unregister_console()
console: Drop misleading comment
console: Use for_each_console() helper in unregister_console()
console: Drop double check for console_drivers being non-NULL
console: Don't perform test for CON_BRL flag
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When dma_mmap_coherent() sets up a mapping to unencrypted coherent memory
under SEV encryption and sometimes under SME encryption, it will actually
set up an encrypted mapping rather than an unencrypted, causing devices
that DMAs from that memory to read encrypted contents. Fix this.
When force_dma_unencrypted() returns true, the linear kernel map of the
coherent pages have had the encryption bit explicitly cleared and the
page content is unencrypted. Make sure that any additional PTEs we set
up to these pages also have the encryption bit cleared by having
dma_pgprot() return a protection with the encryption bit cleared in this
case.
Signed-off-by: Thomas Hellstrom <thellstrom@vmware.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Tom Lendacky <thomas.lendacky@amd.com>
Link: https://lkml.kernel.org/r/20200304114527.3636-3-thomas_os@shipmail.org
This patch turns on xattr support for cgroupfs. This is useful for
letting non-root owners of delegated subtrees attach metadata to
cgroups.
One use case is for subtree owners to tell a userspace out of memory
killer to bias away from killing specific subtrees.
Tests:
[/sys/fs/cgroup]# for i in $(seq 0 130); \
do setfattr workload.slice -n user.name$i -v wow; done
setfattr: workload.slice: No space left on device
setfattr: workload.slice: No space left on device
setfattr: workload.slice: No space left on device
[/sys/fs/cgroup]# for i in $(seq 0 130); \
do setfattr workload.slice --remove user.name$i; done
setfattr: workload.slice: No such attribute
setfattr: workload.slice: No such attribute
setfattr: workload.slice: No such attribute
[/sys/fs/cgroup]# for i in $(seq 0 130); \
do setfattr workload.slice -n user.name$i -v wow; done
setfattr: workload.slice: No space left on device
setfattr: workload.slice: No space left on device
setfattr: workload.slice: No space left on device
`seq 0 130` is inclusive, and 131 - 128 = 3, which is the number of
errors we expect to see.
[/data]# cat testxattr.c
#include <sys/types.h>
#include <sys/xattr.h>
#include <stdio.h>
#include <stdlib.h>
int main() {
char name[256];
char *buf = malloc(64 << 10);
if (!buf) {
perror("malloc");
return 1;
}
for (int i = 0; i < 4; ++i) {
snprintf(name, 256, "user.bigone%d", i);
if (setxattr("/sys/fs/cgroup/system.slice", name, buf,
64 << 10, 0)) {
printf("setxattr failed on iteration=%d\n", i);
return 1;
}
}
return 0;
}
[/data]# ./a.out
setxattr failed on iteration=2
[/data]# ./a.out
setxattr failed on iteration=0
[/sys/fs/cgroup]# setfattr -x user.bigone0 system.slice/
[/sys/fs/cgroup]# setfattr -x user.bigone1 system.slice/
[/data]# ./a.out
setxattr failed on iteration=2
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
This allows the arch code to reset the page tables to cached access when
freeing a dma coherent allocation that was set to uncached using
arch_dma_set_uncached.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Rename the symbol to arch_dma_set_uncached, and pass a size to it as
well as allow an error return. That will allow reusing this hook for
in-place pagetable remapping.
As the in-place remap doesn't always require an explicit cache flush,
also detangle ARCH_HAS_DMA_PREP_COHERENT from ARCH_HAS_DMA_SET_UNCACHED.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
pageno is an int and the PAGE_SHIFT shift is done on an int,
overflowing if the memory is bigger than 2G
This can be reproduced using for example a reserved-memory of 4G
reserved-memory {
#address-cells = <2>;
#size-cells = <2>;
ranges;
reserved_dma: buffer@0 {
compatible = "shared-dma-pool";
no-map;
reg = <0x5 0x00000000 0x1 0x0>;
};
};
Signed-off-by: Kevin Grandemange <kevin.grandemange@allegrodvt.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
prevent inodes from vanishing, but ihold() does not guarantee inode
persistence. Replace the inode pointer with a per boot, machine wide,
unique inode identifier. The second commit fixes the breakage of the hash
mechanism whihc causes a 100% performance regression.
-----BEGIN PGP SIGNATURE-----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=e2iB
-----END PGP SIGNATURE-----
Merge tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull futex fix from Thomas Gleixner:
"Fix for yet another subtle futex issue.
The futex code used ihold() to prevent inodes from vanishing, but
ihold() does not guarantee inode persistence. Replace the inode
pointer with a per boot, machine wide, unique inode identifier.
The second commit fixes the breakage of the hash mechanism which
causes a 100% performance regression"
* tag 'locking-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Unbreak futex hashing
futex: Fix inode life-time issue
which caused sys/sysinfo to be inconsistent with /proc/uptime when read
from a task inside a time namespace.
-----BEGIN PGP SIGNATURE-----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=Is++
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fix from Thomas Gleixner:
"A single fix adding the missing time namespace adjustment in
sys/sysinfo which caused sys/sysinfo to be inconsistent with
/proc/uptime when read from a task inside a time namespace"
* tag 'timers-urgent-2020-03-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sys/sysinfo: Respect boottime inside time namespace
Since the SNAPSHOT_GET_IMAGE_SIZE, SNAPSHOT_AVAIL_SWAP_SIZE, and
SNAPSHOT_ALLOC_SWAP_PAGE ioctls produce an loff_t result, and loff_t is
always 64-bit even in the compat case, there's no reason to have the
special compat handling for these ioctls. Just remove this unneeded
code so that these ioctls call into snapshot_ioctl() directly, doing
just the compat_ptr() conversion on the argument.
(This unnecessary code was also causing a KMSAN false positive.)
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-03-13
The following pull-request contains BPF updates for your *net-next* tree.
We've added 86 non-merge commits during the last 12 day(s) which contain
a total of 107 files changed, 5771 insertions(+), 1700 deletions(-).
The main changes are:
1) Add modify_return attach type which allows to attach to a function via
BPF trampoline and is run after the fentry and before the fexit programs
and can pass a return code to the original caller, from KP Singh.
2) Generalize BPF's kallsyms handling and add BPF trampoline and dispatcher
objects to be visible in /proc/kallsyms so they can be annotated in
stack traces, from Jiri Olsa.
3) Extend BPF sockmap to allow for UDP next to existing TCP support in order
in order to enable this for BPF based socket dispatch, from Lorenz Bauer.
4) Introduce a new bpftool 'prog profile' command which attaches to existing
BPF programs via fentry and fexit hooks and reads out hardware counters
during that period, from Song Liu. Example usage:
bpftool prog profile id 337 duration 3 cycles instructions llc_misses
4228 run_cnt
3403698 cycles (84.08%)
3525294 instructions # 1.04 insn per cycle (84.05%)
13 llc_misses # 3.69 LLC misses per million isns (83.50%)
5) Batch of improvements to libbpf, bpftool and BPF selftests. Also addition
of a new bpf_link abstraction to keep in particular BPF tracing programs
attached even when the applicaion owning them exits, from Andrii Nakryiko.
6) New bpf_get_current_pid_tgid() helper for tracing to perform PID filtering
and which returns the PID as seen by the init namespace, from Carlos Neira.
7) Refactor of RISC-V JIT code to move out common pieces and addition of a
new RV32G BPF JIT compiler, from Luke Nelson.
8) Add gso_size context member to __sk_buff in order to be able to know whether
a given skb is GSO or not, from Willem de Bruijn.
9) Add a new bpf_xdp_output() helper which reuses XDP's existing perf RB output
implementation but can be called from tracepoint programs, from Eelco Chaudron.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Sparse reports a warning at __bpf_prog_enter() and __bpf_prog_exit()
warning: context imbalance in __bpf_prog_enter() - wrong count at exit
warning: context imbalance in __bpf_prog_exit() - unexpected unlock
The root cause is the missing annotation at __bpf_prog_enter()
and __bpf_prog_exit()
Add the missing __acquires(RCU) annotation
Add the missing __releases(RCU) annotation
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200311010908.42366-2-jbi.octave@gmail.com
Now that we have all the objects (bpf_prog, bpf_trampoline,
bpf_dispatcher) linked in bpf_tree, there's no need to have
separate bpf_image tree for images.
Reverting the bpf_image tree together with struct bpf_image,
because it's no longer needed.
Also removing bpf_image_alloc function and adding the original
bpf_jit_alloc_exec_page interface instead.
The kernel_text_address function can now rely only on is_bpf_text_address,
because it checks the bpf_tree that contains all the objects.
Keeping bpf_image_ksym_add and bpf_image_ksym_del because they are
useful wrappers with perf's ksymbol interface calls.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-13-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding dispatchers to kallsyms. It's displayed as
bpf_dispatcher_<NAME>
where NAME is the name of dispatcher.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-12-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding trampolines to kallsyms. It's displayed as
bpf_trampoline_<ID> [bpf]
where ID is the BTF id of the trampoline function.
Adding bpf_image_ksym_add/del functions that setup
the start/end values and call KSYMBOL perf events
handlers.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-11-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Separating /proc/kallsyms add/del code and adding bpf_ksym_add/del
functions for that.
Moving bpf_prog_ksym_node_add/del functions to __bpf_ksym_add/del
and changing their argument to 'struct bpf_ksym' object. This way
we can call them for other bpf objects types like trampoline and
dispatcher.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-10-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding 'prog' bool flag to 'struct bpf_ksym' to mark that
this object belongs to bpf_prog object.
This change allows having bpf_prog objects together with
other types (trampolines and dispatchers) in the single
bpf_tree. It's used when searching for bpf_prog exception
tables by the bpf_prog_ksym_find function, where we need
to get the bpf_prog pointer.
>From now we can safely add bpf_ksym support for trampoline
or dispatcher objects, because we can differentiate them
from bpf_prog objects.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-9-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding bpf_ksym_find function that is used bpf bpf address
lookup functions:
__bpf_address_lookup
is_bpf_text_address
while keeping bpf_prog_kallsyms_find to be used only for lookup
of bpf_prog objects (will happen in following changes).
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-8-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Moving ksym_tnode list node to 'struct bpf_ksym' object,
so the symbol itself can be chained and used in other
objects like bpf_trampoline and bpf_dispatcher.
We need bpf_ksym object to be linked both in bpf_kallsyms
via lnode for /proc/kallsyms and in bpf_tree via tnode for
bpf address lookup functions like __bpf_address_lookup or
bpf_prog_kallsyms_find.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200312195610.346362-7-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding lnode list node to 'struct bpf_ksym' object,
so the struct bpf_ksym itself can be chained and used
in other objects like bpf_trampoline and bpf_dispatcher.
Changing iterator to bpf_ksym in bpf_get_kallsym function.
The ksym->start is holding the prog->bpf_func value,
so it's ok to use it as value in bpf_get_kallsym.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-6-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding name to 'struct bpf_ksym' object to carry the name
of the symbol for bpf_prog, bpf_trampoline, bpf_dispatcher
objects.
The current benefit is that name is now generated only when
the symbol is added to the list, so we don't need to generate
it every time it's accessed.
The future benefit is that we will have all the bpf objects
symbols represented by struct bpf_ksym.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-5-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adding 'struct bpf_ksym' object that will carry the
kallsym information for bpf symbol. Adding the start
and end address to begin with. It will be used by
bpf_prog, bpf_trampoline, bpf_dispatcher objects.
The symbol_start/symbol_end values were originally used
to sort bpf_prog objects. For the address displayed in
/proc/kallsyms we are using prog->bpf_func value.
I'm using the bpf_func value for program symbol start
instead of the symbol_start, because it makes no difference
for sorting bpf_prog objects and we can use it directly as
an address to display it in /proc/kallsyms.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200312195610.346362-4-jolsa@kernel.org
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Instead of requiring users to do three steps for cleaning up bpf_link, its
anon_inode file, and unused fd, abstract that away into bpf_link_cleanup()
helper. bpf_link_defunct() is removed, as it shouldn't be needed as an
individual operation anymore.
v1->v2:
- keep bpf_link_cleanup() static for now (Daniel).
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200313002128.2028680-1-andriin@fb.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Alexei Starovoitov says:
====================
pull-request: bpf 2020-03-12
The following pull-request contains BPF updates for your *net* tree.
We've added 12 non-merge commits during the last 8 day(s) which contain
a total of 12 files changed, 161 insertions(+), 15 deletions(-).
The main changes are:
1) Andrii fixed two bugs in cgroup-bpf.
2) John fixed sockmap.
3) Luke fixed x32 jit.
4) Martin fixed two issues in struct_ops.
5) Yonghong fixed bpf_send_signal.
6) Yoshiki fixed BTF enum.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Introduce new helper that reuses existing xdp perf_event output
implementation, but can be called from raw_tracepoint programs
that receive 'struct xdp_buff *' as a tracepoint argument.
Signed-off-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/158348514556.2239.11050972434793741444.stgit@xdp-tutorial
New bpf helper bpf_get_ns_current_pid_tgid,
This helper will return pid and tgid from current task
which namespace matches dev_t and inode number provided,
this will allows us to instrument a process inside a container.
Signed-off-by: Carlos Neira <cneirabustos@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200304204157.58695-3-cneirabustos@gmail.com
Pull networking fixes from David Miller:
"It looks like a decent sized set of fixes, but a lot of these are one
liner off-by-one and similar type changes:
1) Fix netlink header pointer to calcular bad attribute offset
reported to user. From Pablo Neira Ayuso.
2) Don't double clear PHY interrupts when ->did_interrupt is set,
from Heiner Kallweit.
3) Add missing validation of various (devlink, nl802154, fib, etc.)
attributes, from Jakub Kicinski.
4) Missing *pos increments in various netfilter seq_next ops, from
Vasily Averin.
5) Missing break in of_mdiobus_register() loop, from Dajun Jin.
6) Don't double bump tx_dropped in veth driver, from Jiang Lidong.
7) Work around FMAN erratum A050385, from Madalin Bucur.
8) Make sure ARP header is pulled early enough in bonding driver,
from Eric Dumazet.
9) Do a cond_resched() during multicast processing of ipvlan and
macvlan, from Mahesh Bandewar.
10) Don't attach cgroups to unrelated sockets when in interrupt
context, from Shakeel Butt.
11) Fix tpacket ring state management when encountering unknown GSO
types. From Willem de Bruijn.
12) Fix MDIO bus PHY resume by checking mdio_bus_phy_may_suspend()
only in the suspend context. From Heiner Kallweit"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (112 commits)
net: systemport: fix index check to avoid an array out of bounds access
tc-testing: add ETS scheduler to tdc build configuration
net: phy: fix MDIO bus PM PHY resuming
net: hns3: clear port base VLAN when unload PF
net: hns3: fix RMW issue for VLAN filter switch
net: hns3: fix VF VLAN table entries inconsistent issue
net: hns3: fix "tc qdisc del" failed issue
taprio: Fix sending packets without dequeueing them
net: mvmdio: avoid error message for optional IRQ
net: dsa: mv88e6xxx: Add missing mask of ATU occupancy register
net: memcg: fix lockdep splat in inet_csk_accept()
s390/qeth: implement smarter resizing of the RX buffer pool
s390/qeth: refactor buffer pool code
s390/qeth: use page pointers to manage RX buffer pool
seg6: fix SRv6 L2 tunnels to use IANA-assigned protocol number
net: dsa: Don't instantiate phylink for CPU/DSA ports unless needed
net/packet: tpacket_rcv: do not increment ring index on drop
sxgbe: Fix off by one in samsung driver strncpy size arg
net: caif: Add lockdep expression to RCU traversal primitive
MAINTAINERS: remove Sathya Perla as Emulex NIC maintainer
...
cgrp->root->release_agent_path is protected by both cgroup_mutex and
release_agent_path_lock and readers can hold either one. The
dual-locking scheme was introduced while breaking a locking dependency
issue around cgroup_mutex but doesn't make sense anymore given that
the only remaining reader which uses cgroup_mutex is
cgroup1_releaes_agent().
This patch updates cgroup1_release_agent() to use
release_agent_path_lock so that release_agent_path is always protected
only by release_agent_path_lock.
While at it, convert strlen() based empty string checks to direct
tests on the first character as suggested by Linus.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
[ 7329.671518] BUG: KCSAN: data-race in flush_workqueue / flush_workqueue
[ 7329.671549]
[ 7329.671572] write to 0xffff8881f65fb250 of 8 bytes by task 37173 on cpu 2:
[ 7329.671607] flush_workqueue+0x3bc/0x9b0 (kernel/workqueue.c:2844)
[ 7329.672527]
[ 7329.672540] read to 0xffff8881f65fb250 of 8 bytes by task 37175 on cpu 0:
[ 7329.672571] flush_workqueue+0x28d/0x9b0 (kernel/workqueue.c:2835)
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
When there are no audit rules registered, mandatory records (config,
etc.) are missing their accompanying records (syscall, proctitle, etc.).
This is due to audit context dummy set on syscall entry based on absence
of rules that signals that no other records are to be printed.
Clear the dummy bit if any record is generated.
The proctitle context and dummy checks are pointless since the
proctitle record will not be printed if no syscall records are printed.
Please see upstream github issue
https://github.com/linux-audit/audit-kernel/issues/120
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXmebNQAKCRCRxhvAZXjc
ohidAP4y7sujHKMe87Qd6RFQ+aPTB1cGVgBSyMV5DuvbTW0R9QEA/bWSUtye5+Ln
WRDkXapGM2l36s02xspgokaAhYiFoAE=
=a6eO
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2020-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread fix from Christian Brauner:
"This contains a single fix for a regression which was introduced when
we introduced the ability to select a specific pid at process creation
time.
When this feature is requested, the error value will be set to -EPERM
after exiting the pid allocation loop. This caused EPERM to be
returned when e.g. the init process/child subreaper of the pid
namespace has already died where we used to return ENOMEM before.
The first patch here simply fixes the regression by unconditionally
setting the return value back to ENOMEM again once we've successfully
allocated the requested pid number. This should be easy to backport to
v5.5.
The second patch adds a comment explaining that we must keep returning
ENOMEM since we've been doing it for a long time and have explicitly
documented this behavior for userspace. This seemed worthwhile because
we now have at least two separate example where people tried to change
the return value to something other than ENOMEM (The first version of
the regression fix did that too and the commit message links to an
earlier patch that tried to do the same.).
I have a simple regression test to make sure we catch this regression
in the future but since that introduces a whole new selftest subdir
and test files I'll keep this for v5.7"
* tag 'for-linus-2020-03-10' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
pid: make ENOMEM return value more obvious
pid: Fix error return value in some cases
can break live patching.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXmj5ExQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6quQGAQDO35RBAQDGmpxnSCQPNwrzqokM8p8d
1e1xshwOVnwqgAEA7csC4u1n5Z8ncIl5Pd8ygt4nXeqw4AenHLeZIdhfegc=
=+AeW
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull ftrace fix from Steven Rostedt:
"Have ftrace lookup_rec() return a consistent record otherwise it can
break live patching"
* tag 'trace-v5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Return the first found result in lookup_rec()
It appears that ip ranges can overlap so. In that case lookup_rec()
returns whatever results it got last even if it found nothing in last
searched page.
This breaks an obscure livepatch late module patching usecase:
- load livepatch
- load the patched module
- unload livepatch
- try to load livepatch again
To fix this return from lookup_rec() as soon as it found the record
containing searched-for ip. This used to be this way prior lookup_rec()
introduction.
Link: http://lkml.kernel.org/r/20200306174317.21699-1-asavkov@redhat.com
Cc: stable@vger.kernel.org
Fixes: 7e16f581a8 ("ftrace: Separate out functionality from ftrace_location_range()")
Signed-off-by: Artem Savkov <asavkov@redhat.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add bpf_link_new_file() API for cases when we need to ensure anon_inode is
successfully created before we proceed with expensive BPF program attachment
procedure, which will require equally (if not more so) expensive and
potentially failing compensation detachment procedure just because anon_inode
creation failed. This API allows to simplify code by ensuring first that
anon_inode is created and after BPF program is attached proceed with
fd_install() that can't fail.
After anon_inode file is created, link can't be just kfree()'d anymore,
because its destruction will be performed by deferred file_operations->release
call. For this, bpf_link API required specifying two separate operations:
release() and dealloc(), former performing detachment only, while the latter
frees memory used by bpf_link itself. dealloc() needs to be specified, because
struct bpf_link is frequently embedded into link type-specific container
struct (e.g., struct bpf_raw_tp_link), so bpf_link itself doesn't know how to
properly free the memory. In case when anon_inode file was successfully
created, but subsequent BPF attachment failed, bpf_link needs to be marked as
"defunct", so that file's release() callback will perform only memory
deallocation, but no detachment.
Convert raw tracepoint and tracing attachment to new API and eliminate
detachment from error handling path.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200309231051.1270337-1-andriin@fb.com
We are testing network memory accounting in our setup and noticed
inconsistent network memory usage and often unrelated cgroups network
usage correlates with testing workload. On further inspection, it
seems like mem_cgroup_sk_alloc() and cgroup_sk_alloc() are broken in
irq context specially for cgroup v1.
mem_cgroup_sk_alloc() and cgroup_sk_alloc() can be called in irq context
and kind of assumes that this can only happen from sk_clone_lock()
and the source sock object has already associated cgroup. However in
cgroup v1, where network memory accounting is opt-in, the source sock
can be unassociated with any cgroup and the new cloned sock can get
associated with unrelated interrupted cgroup.
Cgroup v2 can also suffer if the source sock object was created by
process in the root cgroup or if sk_alloc() is called in irq context.
The fix is to just do nothing in interrupt.
WARNING: Please note that about half of the TCP sockets are allocated
from the IRQ context, so, memory used by such sockets will not be
accouted by the memcg.
The stack trace of mem_cgroup_sk_alloc() from IRQ-context:
CPU: 70 PID: 12720 Comm: ssh Tainted: 5.6.0-smp-DEV #1
Hardware name: ...
Call Trace:
<IRQ>
dump_stack+0x57/0x75
mem_cgroup_sk_alloc+0xe9/0xf0
sk_clone_lock+0x2a7/0x420
inet_csk_clone_lock+0x1b/0x110
tcp_create_openreq_child+0x23/0x3b0
tcp_v6_syn_recv_sock+0x88/0x730
tcp_check_req+0x429/0x560
tcp_v6_rcv+0x72d/0xa40
ip6_protocol_deliver_rcu+0xc9/0x400
ip6_input+0x44/0xd0
? ip6_protocol_deliver_rcu+0x400/0x400
ip6_rcv_finish+0x71/0x80
ipv6_rcv+0x5b/0xe0
? ip6_sublist_rcv+0x2e0/0x2e0
process_backlog+0x108/0x1e0
net_rx_action+0x26b/0x460
__do_softirq+0x104/0x2a6
do_softirq_own_stack+0x2a/0x40
</IRQ>
do_softirq.part.19+0x40/0x50
__local_bh_enable_ip+0x51/0x60
ip6_finish_output2+0x23d/0x520
? ip6table_mangle_hook+0x55/0x160
__ip6_finish_output+0xa1/0x100
ip6_finish_output+0x30/0xd0
ip6_output+0x73/0x120
? __ip6_finish_output+0x100/0x100
ip6_xmit+0x2e3/0x600
? ipv6_anycast_cleanup+0x50/0x50
? inet6_csk_route_socket+0x136/0x1e0
? skb_free_head+0x1e/0x30
inet6_csk_xmit+0x95/0xf0
__tcp_transmit_skb+0x5b4/0xb20
__tcp_send_ack.part.60+0xa3/0x110
tcp_send_ack+0x1d/0x20
tcp_rcv_state_process+0xe64/0xe80
? tcp_v6_connect+0x5d1/0x5f0
tcp_v6_do_rcv+0x1b1/0x3f0
? tcp_v6_do_rcv+0x1b1/0x3f0
__release_sock+0x7f/0xd0
release_sock+0x30/0xa0
__inet_stream_connect+0x1c3/0x3b0
? prepare_to_wait+0xb0/0xb0
inet_stream_connect+0x3b/0x60
__sys_connect+0x101/0x120
? __sys_getsockopt+0x11b/0x140
__x64_sys_connect+0x1a/0x20
do_syscall_64+0x51/0x200
entry_SYSCALL_64_after_hwframe+0x44/0xa9
The stack trace of mem_cgroup_sk_alloc() from IRQ-context:
Fixes: 2d75807383 ("mm: memcontrol: consolidate cgroup socket tracking")
Fixes: d979a39d72 ("cgroup: duplicate cgroup reference when cloning sockets")
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Reviewed-by: Roman Gushchin <guro@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull cgroup fixes from Tejun Heo:
- cgroup.procs listing related fixes.
It didn't interlock properly with exiting tasks leaving a short
window where a cgroup has empty cgroup.procs but still can't be
removed and misbehaved on short reads.
- psi_show() crash fix on 32bit ino archs
- Empty release_agent handling fix
* 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup1: don't call release_agent when it is ""
cgroup: fix psi_show() crash on 32bit ino archs
cgroup: Iterate tasks that did not finish do_exit()
cgroup: cgroup_procs_next should increase position index
cgroup-v1: cgroup_pidlist_next should update position index
Pull workqueue fixes from Tejun Heo:
"Workqueue has been incorrectly round-robining per-cpu work items.
Hillf's patch fixes that.
The other patch documents memory-ordering properties of workqueue
operations"
* 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: don't use wq_select_unbound_cpu() for bound works
workqueue: Document (some) memory-ordering properties of {queue,schedule}_work()
btf_enum_check_member() was currently sure to recognize the size of
"enum" type members in struct/union as the size of "int" even if
its size was packed.
This patch fixes BTF enum verification to use the correct size
of member in BPF programs.
Fixes: 179cde8cef ("bpf: btf: Check members of struct/union")
Signed-off-by: Yoshiki Komachi <komachi.yoshiki@gmail.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/1583825550-18606-2-git-send-email-komachi.yoshiki@gmail.com
wq_select_unbound_cpu() is designed for unbound workqueues only, but
it's wrongly called when using a bound workqueue too.
Fixing this ensures work queued to a bound workqueue with
cpu=WORK_CPU_UNBOUND always runs on the local CPU.
Before, that would happen only if wq_unbound_cpumask happened to include
it (likely almost always the case), or was empty, or we got lucky with
forced round-robin placement. So restricting
/sys/devices/virtual/workqueue/cpumask to a small subset of a machine's
CPUs would cause some bound work items to run unexpectedly there.
Fixes: ef55718044 ("workqueue: schedule WORK_CPU_UNBOUND work on wq_unbound_cpumask CPUs")
Cc: stable@vger.kernel.org # v4.5+
Signed-off-by: Hillf Danton <hdanton@sina.com>
[dj: massage changelog]
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
We need the vt fixes in here and it resolves a merge issue with
drivers/tty/vt/selection.c
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no compensating cgroup_bpf_put() for each ancestor cgroup in
cgroup_bpf_inherit(). If compute_effective_progs returns error, those cgroups
won't be freed ever. Fix it by putting them in cleanup code path.
Fixes: e10360f815 ("bpf: cgroup: prevent out-of-order release of cgroup bpf")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Roman Gushchin <guro@fb.com>
Link: https://lore.kernel.org/bpf/20200309224017.1063297-1-andriin@fb.com
The alloc_pid() codepath used to be simpler. With the introducation of the
ability to choose specific pids in 49cb2fc42c ("fork: extend clone3() to
support setting a PID") it got more complex. It hasn't been super obvious
that ENOMEM is returned when the pid namespace init process/child subreaper
of the pid namespace has died. As can be seen from multiple attempts to
improve this see e.g. [1] and most recently [2].
We regressed returning ENOMEM in [3] and [2] restored it. Let's add a
comment on top explaining that this is historic and documented behavior and
cannot easily be changed.
[1]: 35f71bc0a0 ("fork: report pid reservation failure properly")
[2]: b26ebfe12f ("pid: Fix error return value in some cases")
[3]: 49cb2fc42c ("fork: extend clone3() to support setting a PID")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The recent futex inode life time fix changed the ordering of the futex key
union struct members, but forgot to adjust the hash function accordingly,
As a result the hashing omits the leading 64bit and even hashes beyond the
futex key causing a bad hash distribution which led to a ~100% performance
regression.
Hand in the futex key pointer instead of a random struct member and make
the size calculation based of the struct offset.
Fixes: 8019ad13ef ("futex: Fix inode life-time issue")
Reported-by: Rong Chen <rong.a.chen@intel.com>
Decoded-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Rong Chen <rong.a.chen@intel.com>
Link: https://lkml.kernel.org/r/87h7yy90ve.fsf@nanos.tec.linutronix.de
Recent changes to alloc_pid() allow the pid number to be specified on
the command line. If set_tid_size is set, then the code scanning the
levels will hard-set retval to -EPERM, overriding it's previous -ENOMEM
value.
After the code scanning the levels, there are error returns that do not
set retval, assuming it is still set to -ENOMEM.
So set retval back to -ENOMEM after scanning the levels.
Fixes: 49cb2fc42c ("fork: extend clone3() to support setting a PID")
Signed-off-by: Corey Minyard <cminyard@mvista.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Adrian Reber <areber@redhat.com>
Cc: <stable@vger.kernel.org> # 5.5
Link: https://lore.kernel.org/r/20200306172314.12232-1-minyard@acm.org
[christian.brauner@ubuntu.com: fixup commit message]
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
irq_domain_alloc_irqs_hierarchy() has 3 call sites in the compilation unit
but only one of them checks for the pointer which is being dereferenced
inside the called function. Move the check into the function. This allows
for catching the error instead of the following crash:
Unable to handle kernel NULL pointer dereference at virtual address 00000000
PC is at 0x0
LR is at gpiochip_hierarchy_irq_domain_alloc+0x11f/0x140
...
[<c06c23ff>] (gpiochip_hierarchy_irq_domain_alloc)
[<c0462a89>] (__irq_domain_alloc_irqs)
[<c0462dad>] (irq_create_fwspec_mapping)
[<c06c2251>] (gpiochip_to_irq)
[<c06c1c9b>] (gpiod_to_irq)
[<bf973073>] (gpio_irqs_init [gpio_irqs])
[<bf974048>] (gpio_irqs_exit+0xecc/0xe84 [gpio_irqs])
Code: bad PC value
Signed-off-by: Alexander Sverdlin <alexander.sverdlin@nokia.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200306174720.82604-1-alexander.sverdlin@nokia.com
Error injection mechanisms need a half ways safe way to inject interrupts as
invoking generic_handle_irq() or the actual device interrupt handler
directly from e.g. a debugfs write is not guaranteed to be safe.
On x86 generic_handle_irq() is unsafe due to the hardware trainwreck which
is the base of x86 interrupt delivery and affinity management.
Move the irq debugfs injection code into a separate function which can be
used by error injection code as well.
The implementation prevents at least that state is corrupted, but it cannot
close a very tiny race window on x86 which might result in a stale and not
serviced device interrupt under very unlikely circumstances.
This is explicitly for debugging and testing and not for production use or
abuse in random driver code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lkml.kernel.org/r/20200306130623.990928309@linutronix.de
The code sets IRQS_REPLAY unconditionally whether the resend happens or
not. That doesn't have bad side effects right now, but inconsistent state
is always a latent source of problems.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lkml.kernel.org/r/20200306130623.882129117@linutronix.de
In preparation for an interrupt injection interface which can be used
safely by error injection mechanisms. e.g. PCI-E/ AER, add a return value
to check_irq_resend() so errors can be propagated to the caller.
Split out the software resend code so the ugly #ifdef in check_irq_resend()
goes away and the whole thing becomes readable.
Fix up the caller in debugfs. The caller in irq_startup() does not care
about the return value as this is unconditionally invoked for all
interrupts and the resend is best effort anyway.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lkml.kernel.org/r/20200306130623.775200917@linutronix.de
In general calling generic_handle_irq() with interrupts disabled from non
interrupt context is harmless. For some interrupt controllers like the x86
trainwrecks this is outright dangerous as it might corrupt state if an
interrupt affinity change is pending.
Add infrastructure which allows to mark interrupts as unsafe and catch such
usage in generic_handle_irq().
Reported-by: sathyanarayanan.kuppuswamy@linux.intel.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marc Zyngier <maz@kernel.org>
Link: https://lkml.kernel.org/r/20200306130623.590923677@linutronix.de
-----BEGIN PGP SIGNATURE-----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=xwKl
-----END PGP SIGNATURE-----
Merge tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block
Pull block fixes from Jens Axboe:
"Here are a few fixes that should go into this release. This contains:
- Revert of a bad bcache patch from this merge window
- Removed unused function (Daniel)
- Fixup for the blktrace fix from Jan from this release (Cengiz)
- Fix of deeper level bfqq overwrite in BFQ (Carlo)"
* tag 'block-5.6-2020-03-07' of git://git.kernel.dk/linux-block:
block, bfq: fix overwrite of bfq_group pointer in bfq_find_set_group()
blktrace: fix dereference after null check
Revert "bcache: ignore pending signals when creating gc and allocator thread"
block: Remove used kblockd_schedule_work_on()
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXmNvpgAKCRCRxhvAZXjc
ouFvAQDCzfOx1vcEP/nNhYBP2MPuafKclJcoJggC9rSmIvcLiQD/TI+LyHzplD+m
MWSu9NZJ6h6qyjKJivja3/bs8DVEewU=
=4gyS
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2020-03-07' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux
Pull thread fixes from Christian Brauner:
"Here are a few hopefully uncontroversial fixes:
- Use RCU_INIT_POINTER() when initializing rcu protected members in
task_struct to fix sparse warnings.
- Add pidfd_fdinfo_test binary to .gitignore file"
* tag 'for-linus-2020-03-07' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux:
selftests: pidfd: Add pidfd_fdinfo_test in .gitignore
exit: Fix Sparse errors and warnings
fork: Use RCU_INIT_POINTER() instead of rcu_access_pointer()
Many embedded boards have a disconnected TTL level serial which can
generate some garbage that can lead to spurious false sysrq detects.
Currently, sysrq can be either completely disabled for serial console
or always disabled (with CONFIG_MAGIC_SYSRQ_SERIAL), since
commit 732dbf3a61 ("serial: do not accept sysrq characters via serial port")
At Arista, we have such boards that can generate BREAK and random
garbage. While disabling sysrq for serial console would solve
the problem with spurious false sysrq triggers, it's also desirable
to have a way to enable sysrq back.
Having the way to enable sysrq was beneficial to debug lockups with
a manual investigation in field and on the other side preventing false
sysrq detections.
As a preparation to add sysrq_toggle_support() call into uart,
remove a private copy of sysrq_enabled from sysctl - it should reflect
the actual status of sysrq.
Furthermore, the private copy isn't correct already in case
sysrq_always_enabled is true. So, remove __sysrq_enabled and use a
getter-helper sysrq_mask() to check sysrq_key_op enabled status.
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Jiri Slaby <jslaby@suse.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200302175135.269397-2-dima@arista.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/base/arch_topology.c is only built if CONFIG_GENERIC_ARCH_TOPOLOGY=y,
resulting in such build failures:
cpufreq_cooling.c:(.text+0x1e7): undefined reference to `arch_set_thermal_pressure'
Move it to sched/core.c instead, and keep it enabled on x86 despite
us not having a arch_scale_thermal_pressure() facility there, to
build-test this thing.
Cc: Thara Gopinath <thara.gopinath@linaro.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now smp_call_function_single_async() provides the protection that
we'll return with -EBUSY if the csd object is still pending, then we
don't need the rq.hrtick_csd_pending any more.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191216213125.9536-4-peterx@redhat.com
Previously we will raise an warning if we want to insert a csd object
which is with the LOCK flag set, and if it happens we'll also wait for
the lock to be released. However, this operation does not match
perfectly with how the function is named - the name with "_async"
suffix hints that this function should not block, while we will.
This patch changed this behavior by simply return -EBUSY instead of
waiting, at the meantime we allow this operation to happen without
warning the user to change this into a feature when the caller wants
to "insert a csd object, if it's there, just wait for that one".
This is pretty safe because in flush_smp_call_function_queue() for
async csd objects (where csd->flags&SYNC is zero) we'll first do the
unlock then we call the csd->func(). So if we see the csd->flags&LOCK
is true in smp_call_function_single_async(), then it's guaranteed that
csd->func() will be called after this smp_call_function_single_async()
returns -EBUSY.
Update the comment of the function too to refect this.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191216213125.9536-2-peterx@redhat.com
In task_woken_rt() and switched_to_rto() we try trigger push-pull if the
task is unfit.
But the logic is found lacking because if the task was the only one
running on the CPU, then rt_rq is not in overloaded state and won't
trigger a push.
The necessity of this logic was under a debate as well, a summary of
the discussion can be found in the following thread:
https://lore.kernel.org/lkml/20200226160247.iqvdakiqbakk2llz@e107158-lin.cambridge.arm.com/
Remove the logic for now until a better approach is agreed upon.
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 804d402fb6 ("sched/rt: Make RT capacity-aware")
Link: https://lkml.kernel.org/r/20200302132721.8353-6-qais.yousef@arm.com
When implemented RT Capacity Awareness; the logic was done such that if
a task was running on a fitting CPU, then it was sticky and we would try
our best to keep it there.
But as Steve suggested, to adhere to the strict priority rules of RT
class; allow pulling an RT task to unfitting CPU to ensure it gets a
chance to run ASAP.
LINK: https://lore.kernel.org/lkml/20200203111451.0d1da58f@oasis.local.home/
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 804d402fb6 ("sched/rt: Make RT capacity-aware")
Link: https://lkml.kernel.org/r/20200302132721.8353-5-qais.yousef@arm.com
By introducing a new cpupri_find_fitness() function that takes the
fitness_fn as an argument and only called when asym_system static key is
enabled.
cpupri_find() is now a wrapper function that calls cpupri_find_fitness()
passing NULL as a fitness_fn, hence disabling the logic that handles
fitness by default.
LINK: https://lore.kernel.org/lkml/c0772fca-0a4b-c88d-fdf2-5715fcf8447b@arm.com/
Reported-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 804d402fb6 ("sched/rt: Make RT capacity-aware")
Link: https://lkml.kernel.org/r/20200302132721.8353-4-qais.yousef@arm.com
When RT Capacity Aware support was added, the logic in select_task_rq_rt
was modified to force a search for a fitting CPU if the task currently
doesn't run on one.
But if the search failed, and the search was only triggered to fulfill
the fitness request; we could end up selecting a new CPU unnecessarily.
Fix this and re-instate the original behavior by ensuring we bail out
in that case.
This behavior change only affected asymmetric systems that are using
util_clamp to implement capacity aware. None asymmetric systems weren't
affected.
LINK: https://lore.kernel.org/lkml/20200218041620.GD28029@codeaurora.org/
Reported-by: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 804d402fb6 ("sched/rt: Make RT capacity-aware")
Link: https://lkml.kernel.org/r/20200302132721.8353-3-qais.yousef@arm.com
When searching for the best lowest_mask with a fitness_fn passed, make
sure we record the lowest_level that returns a valid lowest_mask so that
we can use that as a fallback in case we fail to find a fitting CPU at
all levels.
The intention in the original patch was not to allow a down migration to
unfitting CPU. But this missed the case where we are already running on
unfitting one.
With this change now RT tasks can still move between unfitting CPUs when
they're already running on such CPU.
And as Steve suggested; to adhere to the strict priority rules of RT, if
a task is already running on a fitting CPU but due to priority it can't
run on it, allow it to downmigrate to unfitting CPU so it can run.
Reported-by: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 804d402fb6 ("sched/rt: Make RT capacity-aware")
Link: https://lkml.kernel.org/r/20200302132721.8353-2-qais.yousef@arm.com
Link: https://lore.kernel.org/lkml/20200203142712.a7yvlyo2y3le5cpn@e107158-lin/
Even when a cgroup is throttled, the group se of a child cgroup can still
be enqueued and its gse->on_rq stays true. When a task is enqueued on such
child, we still have to update the load_avg and increase
h_nr_running of the throttled cfs. Nevertheless, the 1st
for_each_sched_entity() loop is skipped because of gse->on_rq == true and the
2nd loop because the cfs is throttled whereas we have to update both
load_avg with the old h_nr_running and increase h_nr_running in such case.
The same sequence can happen during dequeue when se moves to parent before
breaking in the 1st loop.
Note that the update of load_avg will effectively happen only once in order
to sync up to the throttled time. Next call for updating load_avg will stop
early because the clock stays unchanged.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 6d4d22468d ("sched/fair: Reorder enqueue/dequeue_task_fair path")
Link: https://lkml.kernel.org/r/20200306084208.12583-1-vincent.guittot@linaro.org
When a cfs_rq is throttled, its group entity is dequeued and its running
tasks are removed. We must update runnable_avg with the old h_nr_running
and update group_se->runnable_weight with the new h_nr_running at each
level of the hierarchy.
Reviewed-by: Ben Segall <bsegall@google.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 9f68395333 ("sched/pelt: Add a new runnable average signal")
Link: https://lkml.kernel.org/r/20200227154115.8332-1-vincent.guittot@linaro.org
Since commit 06a76fe08d ("sched/deadline: Move DL related code
from sched/core.c to sched/deadline.c"), DL related code moved to
deadline.c.
Make the following two functions static since they're only used in
deadline.c:
dl_change_utilization()
init_dl_rq_bw_ratio()
Signed-off-by: Yu Chen <chen.yu@easystack.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200228100329.16927-1-chen.yu@easystack.cn
EAS already requires asymmetric CPU capacities to be enabled, and mixing
this with SMT is an aberration, but better be safe than sorry.
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Quentin Perret <qperret@google.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200227191433.31994-2-valentin.schneider@arm.com
Qian Cai reported the following bug:
The linux-next commit ff7db0bf24 ("sched/numa: Prefer using an idle CPU as a
migration target instead of comparing tasks") introduced a boot warning,
[ 86.520534][ T1] WARNING: suspicious RCU usage
[ 86.520540][ T1] 5.6.0-rc3-next-20200227 #7 Not tainted
[ 86.520545][ T1] -----------------------------
[ 86.520551][ T1] kernel/sched/fair.c:5914 suspicious rcu_dereference_check() usage!
[ 86.520555][ T1]
[ 86.520555][ T1] other info that might help us debug this:
[ 86.520555][ T1]
[ 86.520561][ T1]
[ 86.520561][ T1] rcu_scheduler_active = 2, debug_locks = 1
[ 86.520567][ T1] 1 lock held by systemd/1:
[ 86.520571][ T1] #0: ffff8887f4b14848 (&mm->mmap_sem#2){++++}, at: do_page_fault+0x1d2/0x998
[ 86.520594][ T1]
[ 86.520594][ T1] stack backtrace:
[ 86.520602][ T1] CPU: 1 PID: 1 Comm: systemd Not tainted 5.6.0-rc3-next-20200227 #7
task_numa_migrate() checks for idle cores when updating NUMA-related statistics.
This relies on reading a RCU-protected structure in test_idle_cores() via this
call chain
task_numa_migrate
-> update_numa_stats
-> numa_idle_core
-> test_idle_cores
While the locking could be fine-grained, it is more appropriate to acquire
the RCU lock for the entire scan of the domain. This patch removes the
warning triggered at boot time.
Reported-by: Qian Cai <cai@lca.pw>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: ff7db0bf24 ("sched/numa: Prefer using an idle CPU as a migration target instead of comparing tasks")
Link: https://lkml.kernel.org/r/20200227191804.GJ3818@techsingularity.net
Building against the tip/sched/core as ff7db0bf24 ("sched/numa: Prefer
using an idle CPU as a migration target instead of comparing tasks") with
the arm64 defconfig (which doesn't have CONFIG_SCHED_SMT set) leads to:
kernel/sched/fair.c:1525:20: warning: 'test_idle_cores' declared 'static' but never defined [-Wunused-function]
static inline bool test_idle_cores(int cpu, bool def);
^~~~~~~~~~~~~~~
Rather than define it in its own CONFIG_SCHED_SMT #define island, bunch it
up with test_idle_cores().
Reported-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Lukasz Luba <lukasz.luba@arm.com>
[mgorman@techsingularity.net: Edit changelog, minor style change]
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: ff7db0bf24 ("sched/numa: Prefer using an idle CPU as a migration target instead of comparing tasks")
Link: https://lkml.kernel.org/r/20200303110258.1092-3-mgorman@techsingularity.net
Thermal pressure follows pelt signals which means the decay period for
thermal pressure is the default pelt decay period. Depending on SoC
characteristics and thermal activity, it might be beneficial to decay
thermal pressure slower, but still in-tune with the pelt signals. One way
to achieve this is to provide a command line parameter to set a decay
shift parameter to an integer between 0 and 10.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-10-thara.gopinath@linaro.org
cpu_capacity initially reflects the maximum possible capacity of a CPU.
Thermal pressure on a CPU means this maximum possible capacity is
unavailable due to thermal events. This patch subtracts the average
thermal pressure for a CPU from its maximum possible capacity so that
cpu_capacity reflects the remaining maximum capacity.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-8-thara.gopinath@linaro.org
Introduce support in scheduler periodic tick and other CFS bookkeeping
APIs to trigger the process of computing average thermal pressure for a
CPU. Also consider avg_thermal.load_avg in others_have_blocked which
allows for decay of pelt signals.
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-7-thara.gopinath@linaro.org
Extrapolating on the existing framework to track rt/dl utilization using
pelt signals, add a similar mechanism to track thermal pressure. The
difference here from rt/dl utilization tracking is that, instead of
tracking time spent by a CPU running a RT/DL task through util_avg, the
average thermal pressure is tracked through load_avg. This is because
thermal pressure signal is weighted time "delta" capacity unlike util_avg
which is binary. "delta capacity" here means delta between the actual
capacity of a CPU and the decreased capacity a CPU due to a thermal event.
In order to track average thermal pressure, a new sched_avg variable
avg_thermal is introduced. Function update_thermal_load_avg can be called
to do the periodic bookkeeping (accumulate, decay and average) of the
thermal pressure.
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Thara Gopinath <thara.gopinath@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200222005213.3873-2-thara.gopinath@linaro.org
As the vtime is sampled under loose seqcount protection by kcpustat, the
vtime fields may change as the code flows. Where logic dictates a field
has a static value, use a READ_ONCE.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fixes: 74722bb223 ("sched/vtime: Bring up complete kcpustat accessor")
Link: https://lkml.kernel.org/r/20200123180849.28486-1-frederic@kernel.org
If one is monitoring 6 events on 20 cgroups the per-CPU RB tree will
hold 120 events. The scheduling in of the events currently iterates
over all events looking to see which events match the task's cgroup or
its cgroup hierarchy. If a task is in 1 cgroup with 6 events, then 114
events are considered unnecessarily.
This change orders events in the RB tree by cgroup id if it is present.
This means scheduling in may go directly to events associated with the
task's cgroup if one is present. The per-CPU iterator storage in
visit_groups_merge is sized sufficent for an iterator per cgroup depth,
where different iterators are needed for the task's cgroup and parent
cgroups. By considering the set of iterators when visiting, the lowest
group_index event may be selected and the insertion order group_index
property is maintained. This also allows event rotation to function
correctly, as although events are grouped into a cgroup, rotation always
selects the lowest group_index event to rotate (delete/insert into the
tree) and the min heap of iterators make it so that the group_index order
is maintained.
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20190724223746.153620-3-irogers@google.com
Allow the per-CPU min heap storage to have sufficient space for per-cgroup
iterators.
Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-6-irogers@google.com
The storage required for visit_groups_merge's min heap needs to vary in
order to support more iterators, such as when multiple nested cgroups'
events are being visited. This change allows for 2 iterators and doesn't
support growth.
Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-5-irogers@google.com
visit_groups_merge will pick the next event based on when it was
inserted in to the context (perf_event group_index). Events may be per CPU
or for any CPU, but in the future we'd also like to have per cgroup events
to avoid searching all events for the events to schedule for a cgroup.
Introduce a min heap for the events that maintains a property that the
earliest inserted event is always at the 0th element. Initialize the heap
with per-CPU and any-CPU events for the context.
Based-on-work-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-4-irogers@google.com
Move perf_cgroup_connect() after perf_event_alloc(), such that we can
find/use the PMU's cpu context.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ian Rogers <irogers@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200214075133.181299-2-irogers@google.com
We can deduce the ctx and cpuctx from the event, no need to pass them
along. Remove the structure and pass in can_add_hw directly.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Less is more; unify the two very nearly identical function.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that {get,drop}_futex_key_refs() have become a glorified NOP,
remove them entirely.
The only thing get_futex_key_refs() is still doing is an smp_mb(), and
now that we don't need to (ab)use existing atomic ops to obtain them,
we can place it explicitly where we need it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
We always set 'key->private.mm' to 'current->mm', getting an extra
reference on 'current->mm' is quite pointless, because as long as the
task is blocked it isn't going to go away.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
As reported by Jann, ihold() does not in fact guarantee inode
persistence. And instead of making it so, replace the usage of inode
pointers with a per boot, machine wide, unique inode identifier.
This sequence number is global, but shared (file backed) futexes are
rare enough that this should not become a performance issue.
Reported-by: Jann Horn <jannh@google.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Simplify the error handling in pcrypt_create_aead() by taking advantage
of crypto_grab_aead() now handling an ERR_PTR() name and by taking
advantage of crypto_drop_aead() now accepting (as a no-op) a spawn that
hasn't been grabbed yet.
This required also making padata_free_shell() accept a NULL argument.
Signed-off-by: Eric Biggers <ebiggers@google.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
test_run.o is not built when CONFIG_NET is not set and
bpf_prog_test_run_tracing being referenced in bpf_trace.o causes the
linker error:
ld: kernel/trace/bpf_trace.o:(.rodata+0x38): undefined reference to
`bpf_prog_test_run_tracing'
Add a __weak function in bpf_trace.c to handle this.
Fixes: da00d2f117 ("bpf: Add test ops for BPF_PROG_TYPE_TRACING")
Signed-off-by: KP Singh <kpsingh@google.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305220127.29109-1-kpsingh@chromium.org
While well intentioned, checking CAP_MAC_ADMIN for attaching
BPF_MODIFY_RETURN tracing programs to "security_" functions is not
necessary as tracing BPF programs already require CAP_SYS_ADMIN.
Fixes: 6ba43b761c ("bpf: Attachment verification for BPF_MODIFY_RETURN")
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305204955.31123-1-kpsingh@chromium.org
struct_ops map cannot support map_freeze. Otherwise, a struct_ops
cannot be unregistered from the subsystem.
Fixes: 85d33df357 ("bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305013454.535397-1-kafai@fb.com
The current always succeed behavior in bpf_struct_ops_map_delete_elem()
is not ideal for userspace tool. It can be improved to return proper
error value.
If it is in TOBEFREE, it means unregistration has been already done
before but it is in progress and waiting for the subsystem to clear
the refcnt to zero, so -EINPROGRESS.
If it is INIT, it means the struct_ops has not been registered yet,
so -ENOENT.
Fixes: 85d33df357 ("bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200305013447.535326-1-kafai@fb.com
When experimenting with bpf_send_signal() helper in our production
environment (5.2 based), we experienced a deadlock in NMI mode:
#5 [ffffc9002219f770] queued_spin_lock_slowpath at ffffffff8110be24
#6 [ffffc9002219f770] _raw_spin_lock_irqsave at ffffffff81a43012
#7 [ffffc9002219f780] try_to_wake_up at ffffffff810e7ecd
#8 [ffffc9002219f7e0] signal_wake_up_state at ffffffff810c7b55
#9 [ffffc9002219f7f0] __send_signal at ffffffff810c8602
#10 [ffffc9002219f830] do_send_sig_info at ffffffff810ca31a
#11 [ffffc9002219f868] bpf_send_signal at ffffffff8119d227
#12 [ffffc9002219f988] bpf_overflow_handler at ffffffff811d4140
#13 [ffffc9002219f9e0] __perf_event_overflow at ffffffff811d68cf
#14 [ffffc9002219fa10] perf_swevent_overflow at ffffffff811d6a09
#15 [ffffc9002219fa38] ___perf_sw_event at ffffffff811e0f47
#16 [ffffc9002219fc30] __schedule at ffffffff81a3e04d
#17 [ffffc9002219fc90] schedule at ffffffff81a3e219
#18 [ffffc9002219fca0] futex_wait_queue_me at ffffffff8113d1b9
#19 [ffffc9002219fcd8] futex_wait at ffffffff8113e529
#20 [ffffc9002219fdf0] do_futex at ffffffff8113ffbc
#21 [ffffc9002219fec0] __x64_sys_futex at ffffffff81140d1c
#22 [ffffc9002219ff38] do_syscall_64 at ffffffff81002602
#23 [ffffc9002219ff50] entry_SYSCALL_64_after_hwframe at ffffffff81c00068
The above call stack is actually very similar to an issue
reported by Commit eac9153f2b ("bpf/stackmap: Fix deadlock with
rq_lock in bpf_get_stack()") by Song Liu. The only difference is
bpf_send_signal() helper instead of bpf_get_stack() helper.
The above deadlock is triggered with a perf_sw_event.
Similar to Commit eac9153f2b, the below almost identical reproducer
used tracepoint point sched/sched_switch so the issue can be easily caught.
/* stress_test.c */
#include <stdio.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <pthread.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#define THREAD_COUNT 1000
char *filename;
void *worker(void *p)
{
void *ptr;
int fd;
char *pptr;
fd = open(filename, O_RDONLY);
if (fd < 0)
return NULL;
while (1) {
struct timespec ts = {0, 1000 + rand() % 2000};
ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0);
usleep(1);
if (ptr == MAP_FAILED) {
printf("failed to mmap\n");
break;
}
munmap(ptr, 4096 * 64);
usleep(1);
pptr = malloc(1);
usleep(1);
pptr[0] = 1;
usleep(1);
free(pptr);
usleep(1);
nanosleep(&ts, NULL);
}
close(fd);
return NULL;
}
int main(int argc, char *argv[])
{
void *ptr;
int i;
pthread_t threads[THREAD_COUNT];
if (argc < 2)
return 0;
filename = argv[1];
for (i = 0; i < THREAD_COUNT; i++) {
if (pthread_create(threads + i, NULL, worker, NULL)) {
fprintf(stderr, "Error creating thread\n");
return 0;
}
}
for (i = 0; i < THREAD_COUNT; i++)
pthread_join(threads[i], NULL);
return 0;
}
and the following command:
1. run `stress_test /bin/ls` in one windown
2. hack bcc trace.py with the following change:
--- a/tools/trace.py
+++ b/tools/trace.py
@@ -513,6 +513,7 @@ BPF_PERF_OUTPUT(%s);
__data.tgid = __tgid;
__data.pid = __pid;
bpf_get_current_comm(&__data.comm, sizeof(__data.comm));
+ bpf_send_signal(10);
%s
%s
%s.perf_submit(%s, &__data, sizeof(__data));
3. in a different window run
./trace.py -p $(pidof stress_test) t:sched:sched_switch
The deadlock can be reproduced in our production system.
Similar to Song's fix, the fix is to delay sending signal if
irqs is disabled to avoid deadlocks involving with rq_lock.
With this change, my above stress-test in our production system
won't cause deadlock any more.
I also implemented a scale-down version of reproducer in the
selftest (a subsequent commit). With latest bpf-next,
it complains for the following potential deadlock.
[ 32.832450] -> #1 (&p->pi_lock){-.-.}:
[ 32.833100] _raw_spin_lock_irqsave+0x44/0x80
[ 32.833696] task_rq_lock+0x2c/0xa0
[ 32.834182] task_sched_runtime+0x59/0xd0
[ 32.834721] thread_group_cputime+0x250/0x270
[ 32.835304] thread_group_cputime_adjusted+0x2e/0x70
[ 32.835959] do_task_stat+0x8a7/0xb80
[ 32.836461] proc_single_show+0x51/0xb0
...
[ 32.839512] -> #0 (&(&sighand->siglock)->rlock){....}:
[ 32.840275] __lock_acquire+0x1358/0x1a20
[ 32.840826] lock_acquire+0xc7/0x1d0
[ 32.841309] _raw_spin_lock_irqsave+0x44/0x80
[ 32.841916] __lock_task_sighand+0x79/0x160
[ 32.842465] do_send_sig_info+0x35/0x90
[ 32.842977] bpf_send_signal+0xa/0x10
[ 32.843464] bpf_prog_bc13ed9e4d3163e3_send_signal_tp_sched+0x465/0x1000
[ 32.844301] trace_call_bpf+0x115/0x270
[ 32.844809] perf_trace_run_bpf_submit+0x4a/0xc0
[ 32.845411] perf_trace_sched_switch+0x10f/0x180
[ 32.846014] __schedule+0x45d/0x880
[ 32.846483] schedule+0x5f/0xd0
...
[ 32.853148] Chain exists of:
[ 32.853148] &(&sighand->siglock)->rlock --> &p->pi_lock --> &rq->lock
[ 32.853148]
[ 32.854451] Possible unsafe locking scenario:
[ 32.854451]
[ 32.855173] CPU0 CPU1
[ 32.855745] ---- ----
[ 32.856278] lock(&rq->lock);
[ 32.856671] lock(&p->pi_lock);
[ 32.857332] lock(&rq->lock);
[ 32.857999] lock(&(&sighand->siglock)->rlock);
Deadlock happens on CPU0 when it tries to acquire &sighand->siglock
but it has been held by CPU1 and CPU1 tries to grab &rq->lock
and cannot get it.
This is not exactly the callstack in our production environment,
but sympotom is similar and both locks are using spin_lock_irqsave()
to acquire the lock, and both involves rq_lock. The fix to delay
sending signal when irq is disabled also fixed this issue.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200304191104.2796501-1-yhs@fb.com
There was a recent change in blktrace.c that added a RCU protection to
`q->blk_trace` in order to fix a use-after-free issue during access.
However the change missed an edge case that can lead to dereferencing of
`bt` pointer even when it's NULL:
Coverity static analyzer marked this as a FORWARD_NULL issue with CID
1460458.
```
/kernel/trace/blktrace.c: 1904 in sysfs_blk_trace_attr_store()
1898 ret = 0;
1899 if (bt == NULL)
1900 ret = blk_trace_setup_queue(q, bdev);
1901
1902 if (ret == 0) {
1903 if (attr == &dev_attr_act_mask)
>>> CID 1460458: Null pointer dereferences (FORWARD_NULL)
>>> Dereferencing null pointer "bt".
1904 bt->act_mask = value;
1905 else if (attr == &dev_attr_pid)
1906 bt->pid = value;
1907 else if (attr == &dev_attr_start_lba)
1908 bt->start_lba = value;
1909 else if (attr == &dev_attr_end_lba)
```
Added a reassignment with RCU annotation to fix the issue.
Fixes: c780e86dd4 ("blktrace: Protect q->blk_trace with RCU")
Cc: stable@vger.kernel.org
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bob Liu <bob.liu@oracle.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Cengiz Can <cengiz@kernel.wtf>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The restriction introduced in 7a0df7fbc1 ("seccomp: Make NEW_LISTENER and
TSYNC flags exclusive") is mostly artificial: there is enough information
in a seccomp user notification to tell which thread triggered a
notification. The reason it was introduced is because TSYNC makes the
syscall return a thread-id on failure, and NEW_LISTENER returns an fd, and
there's no way to distinguish between these two cases (well, I suppose the
caller could check all fds it has, then do the syscall, and if the return
value was an fd that already existed, then it must be a thread id, but
bleh).
Matthew would like to use these two flags together in the Chrome sandbox
which wants to use TSYNC for video drivers and NEW_LISTENER to proxy
syscalls.
So, let's fix this ugliness by adding another flag, TSYNC_ESRCH, which
tells the kernel to just return -ESRCH on a TSYNC error. This way,
NEW_LISTENER (and any subsequent seccomp() commands that want to return
positive values) don't conflict with each other.
Suggested-by: Matthew Denton <mpdenton@google.com>
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Link: https://lore.kernel.org/r/20200304180517.23867-1-tycho@tycho.ws
Signed-off-by: Kees Cook <keescook@chromium.org>
The current fexit and fentry tests rely on a different program to
exercise the functions they attach to. Instead of doing this, implement
the test operations for tracing which will also be used for
BPF_MODIFY_RETURN in a subsequent patch.
Also, clean up the fexit test to use the generated skeleton.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200304191853.1529-7-kpsingh@chromium.org
- Allow BPF_MODIFY_RETURN attachment only to functions that are:
* Whitelisted for error injection by checking
within_error_injection_list. Similar discussions happened for the
bpf_override_return helper.
* security hooks, this is expected to be cleaned up with the LSM
changes after the KRSI patches introduce the LSM_HOOK macro:
https://lore.kernel.org/bpf/20200220175250.10795-1-kpsingh@chromium.org/
- The attachment is currently limited to functions that return an int.
This can be extended later other types (e.g. PTR).
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200304191853.1529-5-kpsingh@chromium.org
When multiple programs are attached, each program receives the return
value from the previous program on the stack and the last program
provides the return value to the attached function.
The fmod_ret bpf programs are run after the fentry programs and before
the fexit programs. The original function is only called if all the
fmod_ret programs return 0 to avoid any unintended side-effects. The
success value, i.e. 0 is not currently configurable but can be made so
where user-space can specify it at load time.
For example:
int func_to_be_attached(int a, int b)
{ <--- do_fentry
do_fmod_ret:
<update ret by calling fmod_ret>
if (ret != 0)
goto do_fexit;
original_function:
<side_effects_happen_here>
} <--- do_fexit
The fmod_ret program attached to this function can be defined as:
SEC("fmod_ret/func_to_be_attached")
int BPF_PROG(func_name, int a, int b, int ret)
{
// This will skip the original function logic.
return 1;
}
The first fmod_ret program is passed 0 in its return argument.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200304191853.1529-4-kpsingh@chromium.org
As we need to introduce a third type of attachment for trampolines, the
flattened signature of arch_prepare_bpf_trampoline gets even more
complicated.
Refactor the prog and count argument to arch_prepare_bpf_trampoline to
use bpf_tramp_progs to simplify the addition and accounting for new
attachment types.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200304191853.1529-2-kpsingh@chromium.org
Older (and maybe current) versions of systemd set release_agent to "" when
shutting down, but do not set notify_on_release to 0.
Since 64e90a8acb ("Introduce STATIC_USERMODEHELPER to mediate
call_usermodehelper()"), we filter out such calls when the user mode helper
path is "". However, when used in conjunction with an actual (i.e. non "")
STATIC_USERMODEHELPER, the path is never "", so the real usermode helper
will be called with argv[0] == "".
Let's avoid this by not invoking the release_agent when it is "".
Signed-off-by: Tycho Andersen <tycho@tycho.ws>
Signed-off-by: Tejun Heo <tj@kernel.org>
The return values of workqueue_init() and workqueue_early_int() are
always 0, and there is no usage of their return value. So just make
them return void.
Signed-off-by: Yu Chen <chen.yu@easystack.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
Similar to the commit d749534322 ("cgroup: fix incorrect
WARN_ON_ONCE() in cgroup_setup_root()"), cgroup_id(root_cgrp) does not
equal to 1 on 32bit ino archs which triggers all sorts of issues with
psi_show() on s390x. For example,
BUG: KASAN: slab-out-of-bounds in collect_percpu_times+0x2d0/
Read of size 4 at addr 000000001e0ce000 by task read_all/3667
collect_percpu_times+0x2d0/0x798
psi_show+0x7c/0x2a8
seq_read+0x2ac/0x830
vfs_read+0x92/0x150
ksys_read+0xe2/0x188
system_call+0xd8/0x2b4
Fix it by using cgroup_ino().
Fixes: 743210386c ("cgroup: use cgrp->kn->id as the cgroup ID")
Signed-off-by: Qian Cai <cai@lca.pw>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v5.5
The tick_periodic() function is used at the beginning part of the
bootup process for time keeping while the other clock sources are
being initialized.
The current code assumes that all the timer interrupts are handled in
a timely manner with no missing ticks. That is not actually true. Some
ticks are missed and there are some discrepancies between the tick time
(jiffies) and the timestamp reported in the kernel log. Some systems,
however, are more prone to missing ticks than the others. In the extreme
case, the discrepancy can actually cause a soft lockup message to be
printed by the watchdog kthread. For example, on a Cavium ThunderX2
Sabre arm64 system:
[ 25.496379] watchdog: BUG: soft lockup - CPU#14 stuck for 22s!
On that system, the missing ticks are especially prevalent during the
smp_init() phase of the boot process. With an instrumented kernel,
it was found that it took about 24s as reported by the timestamp for
the tick to accumulate 4s of time.
Investigation and bisection done by others seemed to point to the
commit 73f3816609 ("arm64: Advertise mitigation of Spectre-v2, or
lack thereof") as the culprit. It could also be a firmware issue as
new firmware was promised that would fix the issue.
To properly address this problem, stop assuming that there will be no
missing tick in tick_periodic(). Modify it to follow the example of
tick_do_update_jiffies64() by using another reference clock to check for
missing ticks. Since the watchdog timer uses running_clock(), it is used
here as the reference. With this applied, the soft lockup problem in the
affected arm64 system is gone and tick time tracks much more closely to the
timestamp time.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200207193929.27308-1-longman@redhat.com
do_div() does a 64-by-32 division at least on 32bit platforms, while the
divisor 'div' is explicitly casted to unsigned long, thus 64-bit on 64-bit
platforms.
The code already ensures that the divisor is less than 2^32. Hence the
proper cast type is u32.
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200130130851.29204-1-wenyang@linux.alibaba.com
While unlikely the divisor in scale64_check_overflow() could be >= 32bit in
scale64_check_overflow(). do_div() truncates the divisor to 32bit at least
on 32bit platforms.
Use div64_u64() instead to avoid the truncation to 32-bit.
[ tglx: Massaged changelog ]
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200120100523.45656-1-wenyang@linux.alibaba.com
The reasons why the extra posix_cpu_timers_exit_group() invocation has been
added are not entirely clear from the commit message. Today all that
posix_cpu_timers_exit_group() does is stop timers that are tracking the
task from firing. Every other operation on those timers is still allowed.
The practical implication of this is posix_cpu_timer_del() which could
not get the siglock after the thread group leader has exited (because
sighand == NULL) would be able to run successfully because the timer
was already dequeued.
With that locking issue fixed there is no point in disabling all of the
timers. So remove this ``tempoary'' hack.
Fixes: e0a7021710 ("posix-cpu-timers: workaround to suppress the problems with mt exec")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87o8tityzs.fsf@x220.int.ebiederm.org
posix cpu timers do not handle the death of a process well.
This is most clearly seen when a multi-threaded process calls exec from a
thread that is not the leader of the thread group. The posix cpu timer code
continues to pin the old thread group leader and is unable to find the
siglock from there.
This results in posix_cpu_timer_del being unable to delete a timer,
posix_cpu_timer_set being unable to set a timer. Further to compensate for
the problems in posix_cpu_timer_del on a multi-threaded exec all timers
that point at the multi-threaded task are stopped.
The code for the timers fundamentally needs to check if the target
process/thread is alive. This needs an extra level of indirection. This
level of indirection is already available in struct pid.
So replace cpu.task with cpu.pid to get the needed extra layer of
indirection.
In addition to handling things more cleanly this reduces the amount of
memory a timer can pin when a process exits and then is reaped from
a task_struct to the vastly smaller struct pid.
Fixes: e0a7021710 ("posix-cpu-timers: workaround to suppress the problems with mt exec")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87wo86tz6d.fsf@x220.int.ebiederm.org
The target_value field in struct pm_qos_constraints is used for
lockless access to the effective constraint value of a given QoS
list, so the readers of it cannot expect it to always reflect the
most recent effective constraint value. However, they can and do
expect it to be equal to a valid effective constraint value computed
at a certain time in the past (event though it may not be the most
recent one), so add READ|WRITE_ONCE() annotations around the
target_value accesses to prevent the compiler from possibly causing
that expectation to be unmet by generating code in an exceptionally
convoluted way.
Signed-off-by: Qian Cai <cai@lca.pw>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Commit 567cd4da54 ("ring-buffer: User context bit recursion checking")
added the TRACE_BUFFER bits to be used in the current task's trace_recursion
field. But the final submission of the logic removed the use of those bits,
but never removed the bits themselves (they were never used in upstream
Linux). These can be safely removed.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The hwlat tracer runs a loop of width time during a given window. It then
reports the max latency over a given threshold and records a timestamp. But
this timestamp is the time after the width has finished, and not the time it
actually triggered.
Record the actual time when the latency was greater than the threshold as
well as the number of times it was greater in a given width per window.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The sysinfo() syscall includes uptime in seconds but has no correction for
time namespaces which makes it inconsistent with the /proc/uptime inside of
a time namespace.
Add the missing time namespace adjustment call.
Signed-off-by: Cyril Hrubis <chrubis@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Dmitry Safonov <dima@arista.com>
Link: https://lkml.kernel.org/r/20200303150638.7329-1-chrubis@suse.cz
Introduce bpf_link abstraction, representing an attachment of BPF program to
a BPF hook point (e.g., tracepoint, perf event, etc). bpf_link encapsulates
ownership of attached BPF program, reference counting of a link itself, when
reference from multiple anonymous inodes, as well as ensures that release
callback will be called from a process context, so that users can safely take
mutex locks and sleep.
Additionally, with a new abstraction it's now possible to generalize pinning
of a link object in BPF FS, allowing to explicitly prevent BPF program
detachment on process exit by pinning it in a BPF FS and let it open from
independent other process to keep working with it.
Convert two existing bpf_link-like objects (raw tracepoint and tracing BPF
program attachments) into utilizing bpf_link framework, making them pinnable
in BPF FS. More FD-based bpf_links will be added in follow up patches.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200303043159.323675-2-andriin@fb.com
As Peter pointed out, task_work() can avoid ->pi_lock and cmpxchg()
if task->task_works == NULL && !PF_EXITING.
And in fact the only reason why task_work_run() needs ->pi_lock is
the possible race with task_work_cancel(), we can optimize this code
and make the locking more clear.
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Pull scheduler fix from Ingo Molnar:
"Fix a scheduler statistics bug"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix statistics for find_idlest_group()
The task has been already computed to take siglock before calling
arm_timer. So pass the benefit of that labor into arm_timer().
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/8736auvdt1.fsf@x220.int.ebiederm.org
As of e78c349679 ("time, signal: Protect resource use statistics
with seqlock") cpu_clock_sample_group no longers needs siglock
protection. Unfortunately no one realized it at the time.
Remove the extra locking that is for cpu_clock_sample_group and not
for cpu_clock_sample. This significantly simplifies the code.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/878skmvdts.fsf@x220.int.ebiederm.org
As of e78c349679 ("time, signal: Protect resource use statistics with
seqlock") cpu_clock_sample_group() no longer needs siglock protection so
remove the stale comment.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87eeuevduq.fsf@x220.int.ebiederm.org
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-02-28
The following pull-request contains BPF updates for your *net-next* tree.
We've added 41 non-merge commits during the last 7 day(s) which contain
a total of 49 files changed, 1383 insertions(+), 499 deletions(-).
The main changes are:
1) BPF and Real-Time nicely co-exist.
2) bpftool feature improvements.
3) retrieve bpf_sk_storage via INET_DIAG.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Oleg wrote a very informative comment, but with the removal of
proc_cleanup_work it is no longer accurate.
Rewrite the comment so that it only talks about the details
that are still relevant, and hopefully is a little clearer.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
There remains no more code in the kernel using pids_ns->proc_mnt,
therefore remove it from the kernel.
The big benefit of this change is that one of the most error prone and
tricky parts of the pid namespace implementation, maintaining kernel
mounts of proc is removed.
In addition removing the unnecessary complexity of the kernel mount
fixes a regression that caused the proc mount options to be ignored.
Now that the initial mount of proc comes from userspace, those mount
options are again honored. This fixes Android's usage of the proc
hidepid option.
Reported-by: Alistair Strachan <astrachan@google.com>
Fixes: e94591d0d9 ("proc: Convert proc_mount to use mount_ns.")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Fix a recent cpufreq initialization regression (Rafael Wysocki),
revert a devfreq commit that made incompatible changes and broke
user land on some systems (Orson Zhai), drop a stale reference to
a document that has gone away recently (Jonathan Neuschäfer) and
fix a typo in a hibernation code comment (Alexandre Belloni).
-----BEGIN PGP SIGNATURE-----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=ySea
-----END PGP SIGNATURE-----
Merge tag 'pm-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Fix a recent cpufreq initialization regression (Rafael Wysocki),
revert a devfreq commit that made incompatible changes and broke user
land on some systems (Orson Zhai), drop a stale reference to a
document that has gone away recently (Jonathan Neuschäfer), and fix a
typo in a hibernation code comment (Alexandre Belloni)"
* tag 'pm-5.6-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: Fix policy initialization for internal governor drivers
Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"
PM / hibernate: fix typo "reserverd_size" -> "reserved_size"
Documentation: power: Drop reference to interface.rst
This patch fixes the following sparse error:
kernel/exit.c:627:25: error: incompatible types in comparison expression
And the following warning:
kernel/exit.c:626:40: warning: incorrect type in assignment
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: edit commit message]
Link: https://lore.kernel.org/r/20200130062028.4870-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
* pm-sleep:
PM / hibernate: fix typo "reserverd_size" -> "reserved_size"
Documentation: power: Drop reference to interface.rst
* pm-devfreq:
Revert "PM / devfreq: Modify the device name as devfreq(X) for sysfs"
This patch adds INET_DIAG support to bpf_sk_storage.
1. Although this series adds bpf_sk_storage diag capability to inet sk,
bpf_sk_storage is in general applicable to all fullsock. Hence, the
bpf_sk_storage logic will operate on SK_DIAG_* nlattr. The caller
will pass in its specific nesting nlattr (e.g. INET_DIAG_*) as
the argument.
2. The request will be like:
INET_DIAG_REQ_SK_BPF_STORAGES (nla_nest) (defined in latter patch)
SK_DIAG_BPF_STORAGE_REQ_MAP_FD (nla_put_u32)
SK_DIAG_BPF_STORAGE_REQ_MAP_FD (nla_put_u32)
......
Considering there could have multiple bpf_sk_storages in a sk,
instead of reusing INET_DIAG_INFO ("ss -i"), the user can select
some specific bpf_sk_storage to dump by specifying an array of
SK_DIAG_BPF_STORAGE_REQ_MAP_FD.
If no SK_DIAG_BPF_STORAGE_REQ_MAP_FD is specified (i.e. an empty
INET_DIAG_REQ_SK_BPF_STORAGES), it will dump all bpf_sk_storages
of a sk.
3. The reply will be like:
INET_DIAG_BPF_SK_STORAGES (nla_nest) (defined in latter patch)
SK_DIAG_BPF_STORAGE (nla_nest)
SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
SK_DIAG_BPF_STORAGE (nla_nest)
SK_DIAG_BPF_STORAGE_MAP_ID (nla_put_u32)
SK_DIAG_BPF_STORAGE_MAP_VALUE (nla_reserve_64bit)
......
4. Unlike other INET_DIAG info of a sk which is pretty static, the size
required to dump the bpf_sk_storage(s) of a sk is dynamic as the
system adding more bpf_sk_storage_map. It is hard to set a static
min_dump_alloc size.
Hence, this series learns it at the runtime and adjust the
cb->min_dump_alloc as it iterates all sk(s) of a system. The
"unsigned int *res_diag_size" in bpf_sk_storage_diag_put()
is for this purpose.
The next patch will update the cb->min_dump_alloc as it
iterates the sk(s).
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200225230421.1975729-1-kafai@fb.com
The mptcp conflict was overlapping additions.
The SMC conflict was an additional and removal happening at the same
time.
Signed-off-by: David S. Miller <davem@davemloft.net>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200227001744.GA3317@embeddedor
-----BEGIN PGP SIGNATURE-----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=DyVs
-----END PGP SIGNATURE-----
Merge tag 'audit-pr-20200226' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit fixes from Paul Moore:
"Two fixes for problems found by syzbot:
- Moving audit filter structure fields into a union caused some
problems in the code which populates that filter structure.
We keep the union (that idea is a good one), but we are fixing the
code so that it doesn't needlessly set fields in the union and mess
up the error handling.
- The audit_receive_msg() function wasn't validating user input as
well as it should in all cases, we add the necessary checks"
* tag 'audit-pr-20200226' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: always check the netlink payload length in audit_receive_msg()
audit: fix error handling in audit_data_to_entry()
sgs->group_weight is not set while gathering statistics in
update_sg_wakeup_stats(). This means that a group can be classified as
fully busy with 0 running tasks if utilization is high enough.
This path is mainly used for fork and exec.
Fixes: 57abff067a ("sched/fair: Rework find_idlest_group()")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Link: https://lore.kernel.org/r/20200218144534.4564-1-vincent.guittot@linaro.org
Change in API of bootconfig (before it comes live in a release)
- Have a magic value "BOOTCONFIG" in initrd to know a bootconfig exists
- Set CONFIG_BOOT_CONFIG to 'n' by default
- Show error if "bootconfig" on cmdline but not compiled in
- Prevent redefining the same value
- Have a way to append values
- Added a SELECT BLK_DEV_INITRD to fix a build failure
Synthetic event fixes:
- Switch to raw_smp_processor_id() for recording CPU value in preempt
section. (No care for what the value actually is)
- Fix samples always recording u64 values
- Fix endianess
- Check number of values matches number of fields
- Fix a printing bug
Fix of trace_printk() breaking postponed start up tests
Make a function static that is only used in a single file.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXlW4vxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qtioAP0WLEm3dWO0z3321h/a0DSshC+Bslu3
HDPTsGVGrXmvggEA/lr1ikRHd8PsO7zW8BfaZMxoXaTqXiuSrzEWxnMlFw0=
=O8PM
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing and bootconfig updates:
"Fixes and changes to bootconfig before it goes live in a release.
Change in API of bootconfig (before it comes live in a release):
- Have a magic value "BOOTCONFIG" in initrd to know a bootconfig
exists
- Set CONFIG_BOOT_CONFIG to 'n' by default
- Show error if "bootconfig" on cmdline but not compiled in
- Prevent redefining the same value
- Have a way to append values
- Added a SELECT BLK_DEV_INITRD to fix a build failure
Synthetic event fixes:
- Switch to raw_smp_processor_id() for recording CPU value in preempt
section. (No care for what the value actually is)
- Fix samples always recording u64 values
- Fix endianess
- Check number of values matches number of fields
- Fix a printing bug
Fix of trace_printk() breaking postponed start up tests
Make a function static that is only used in a single file"
* tag 'trace-v5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
bootconfig: Fix CONFIG_BOOTTIME_TRACING dependency issue
bootconfig: Add append value operator support
bootconfig: Prohibit re-defining value on same key
bootconfig: Print array as multiple commands for legacy command line
bootconfig: Reject subkey and value on same parent key
tools/bootconfig: Remove unneeded error message silencer
bootconfig: Add bootconfig magic word for indicating bootconfig explicitly
bootconfig: Set CONFIG_BOOT_CONFIG=n by default
tracing: Clear trace_state when starting trace
bootconfig: Mark boot_config_checksum() static
tracing: Disable trace_printk() on post poned tests
tracing: Have synthetic event test use raw_smp_processor_id()
tracing: Fix number printing bug in print_synth_event()
tracing: Check that number of vals matches number of synth event fields
tracing: Make synth_event trace functions endian-correct
tracing: Make sure synth_event_trace() example always uses u64
When queueing a signal, we increment both the users count of pending
signals (for RLIMIT_SIGPENDING tracking) and we increment the refcount
of the user struct itself (because we keep a reference to the user in
the signal structure in order to correctly account for it when freeing).
That turns out to be fairly expensive, because both of them are atomic
updates, and particularly under extreme signal handling pressure on big
machines, you can get a lot of cache contention on the user struct.
That can then cause horrid cacheline ping-pong when you do these
multiple accesses.
So change the reference counting to only pin the user for the _first_
pending signal, and to unpin it when the last pending signal is
dequeued. That means that when a user sees a lot of concurrent signal
queuing - which is the only situation when this matters - the only
atomic access needed is generally the 'sigpending' count update.
This was noticed because of a particularly odd timing artifact on a
dual-socket 96C/192T Cascade Lake platform: when you get into bad
contention, on that machine for some reason seems to be much worse when
the contention happens in the upper 32-byte half of the cacheline.
As a result, the kernel test robot will-it-scale 'signal1' benchmark had
an odd performance regression simply due to random alignment of the
'struct user_struct' (and pointed to a completely unrelated and
apparently nonsensical commit for the regression).
Avoiding the double increments (and decrements on the dequeueing side,
of course) makes for much less contention and hugely improved
performance on that will-it-scale microbenchmark.
Quoting Feng Tang:
"It makes a big difference, that the performance score is tripled! bump
from original 17000 to 54000. Also the gap between 5.0-rc6 and
5.0-rc6+Jiri's patch is reduced to around 2%"
[ The "2% gap" is the odd cacheline placement difference on that
platform: under the extreme contention case, the effect of which half
of the cacheline was hot was 5%, so with the reduced contention the
odd timing artifact is reduced too ]
It does help in the non-contended case too, but is not nearly as
noticeable.
Reported-and-tested-by: Feng Tang <feng.tang@intel.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Huang, Ying <ying.huang@intel.com>
Cc: Philip Li <philip.li@intel.com>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit d8a953ddde ("bootconfig: Set CONFIG_BOOT_CONFIG=n by
default") also changed the CONFIG_BOOTTIME_TRACING to select
CONFIG_BOOT_CONFIG to show the boot-time tracing on the menu,
it introduced wrong dependencies with BLK_DEV_INITRD as below.
WARNING: unmet direct dependencies detected for BOOT_CONFIG
Depends on [n]: BLK_DEV_INITRD [=n]
Selected by [y]:
- BOOTTIME_TRACING [=y] && TRACING_SUPPORT [=y] && FTRACE [=y] && TRACING [=y]
This makes the CONFIG_BOOT_CONFIG selects CONFIG_BLK_DEV_INITRD to
fix this error and make CONFIG_BOOTTIME_TRACING=n by default, so
that both boot-time tracing and boot configuration off but those
appear on the menu list.
Link: http://lkml.kernel.org/r/158264140162.23842.11237423518607465535.stgit@devnote2
Fixes: d8a953ddde ("bootconfig: Set CONFIG_BOOT_CONFIG=n by default")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Compiled-tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
KASAN is reporting that __blk_add_trace() has a use-after-free issue
when accessing q->blk_trace. Indeed the switching of block tracing (and
thus eventual freeing of q->blk_trace) is completely unsynchronized with
the currently running tracing and thus it can happen that the blk_trace
structure is being freed just while __blk_add_trace() works on it.
Protect accesses to q->blk_trace by RCU during tracing and make sure we
wait for the end of RCU grace period when shutting down tracing. Luckily
that is rare enough event that we can afford that. Note that postponing
the freeing of blk_trace to an RCU callback should better be avoided as
it could have unexpected user visible side-effects as debugfs files
would be still existing for a short while block tracing has been shut
down.
Link: https://bugzilla.kernel.org/show_bug.cgi?id=205711
CC: stable@vger.kernel.org
Reviewed-by: Chaitanya Kulkarni <chaitanya.kulkarni@wdc.com>
Reviewed-by: Ming Lei <ming.lei@redhat.com>
Tested-by: Ming Lei <ming.lei@redhat.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reported-by: Tristan Madani <tristmd@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In a RT kernel down_read_trylock() cannot be used from NMI context and
up_read_non_owner() is another problematic issue.
So in such a configuration, simply elide the annotated stackmap and
just report the raw IPs.
In the longer term, it might be possible to provide a atomic friendly
versions of the page cache traversal which will at least provide the info
if the pages are resident and don't need to be paged in.
[ tglx: Use IS_ENABLED() to avoid the #ifdeffery, fixup the irq work
callback and add a comment ]
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145644.708960317@linutronix.de
The LPM trie map cannot be used in contexts like perf, kprobes and tracing
as this map type dynamically allocates memory.
The memory allocation happens with a raw spinlock held which is a truly
spinning lock on a PREEMPT RT enabled kernel which disables preemption and
interrupts.
As RT does not allow memory allocation from such a section for various
reasons, convert the raw spinlock to a regular spinlock.
On a RT enabled kernel these locks are substituted by 'sleeping' spinlocks
which provide the proper protection but keep the code preemptible.
On a non-RT kernel regular spinlocks map to raw spinlocks, i.e. this does
not cause any functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145644.602129531@linutronix.de
PREEMPT_RT forbids certain operations like memory allocations (even with
GFP_ATOMIC) from atomic contexts. This is required because even with
GFP_ATOMIC the memory allocator calls into code pathes which acquire locks
with long held lock sections. To ensure the deterministic behaviour these
locks are regular spinlocks, which are converted to 'sleepable' spinlocks
on RT. The only true atomic contexts on an RT kernel are the low level
hardware handling, scheduling, low level interrupt handling, NMIs etc. None
of these contexts should ever do memory allocations.
As regular device interrupt handlers and soft interrupts are forced into
thread context, the existing code which does
spin_lock*(); alloc(GPF_ATOMIC); spin_unlock*();
just works.
In theory the BPF locks could be converted to regular spinlocks as well,
but the bucket locks and percpu_freelist locks can be taken from arbitrary
contexts (perf, kprobes, tracepoints) which are required to be atomic
contexts even on RT. These mechanisms require preallocated maps, so there
is no need to invoke memory allocations within the lock held sections.
BPF maps which need dynamic allocation are only used from (forced) thread
context on RT and can therefore use regular spinlocks which in turn allows
to invoke memory allocations from the lock held section.
To achieve this make the hash bucket lock a union of a raw and a regular
spinlock and initialize and lock/unlock either the raw spinlock for
preallocated maps or the regular variant for maps which require memory
allocations.
On a non RT kernel this distinction is neither possible nor required.
spinlock maps to raw_spinlock and the extra code and conditional is
optimized out by the compiler. No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145644.509685912@linutronix.de
As a preparation for making the BPF locking RT friendly, factor out the
hash bucket lock operations into inline functions. This allows to do the
necessary RT modification in one place instead of sprinkling it all over
the place. No functional change.
The now unused htab argument of the lock/unlock functions will be used in
the next step which adds PREEMPT_RT support.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145644.420416916@linutronix.de
The required protection is that the caller cannot be migrated to a
different CPU as these functions end up in places which take either a hash
bucket lock or might trigger a kprobe inside the memory allocator. Both
scenarios can lead to deadlocks. The deadlock prevention is per CPU by
incrementing a per CPU variable which temporarily blocks the invocation of
BPF programs from perf and kprobes.
Replace the open coded preempt_[dis|en]able and __this_cpu_[inc|dec] pairs
with the new helper functions. These functions are already prepared to make
BPF work on PREEMPT_RT enabled kernels. No functional change for !RT
kernels.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145644.317843926@linutronix.de
The required protection is that the caller cannot be migrated to a
different CPU as these places take either a hash bucket lock or might
trigger a kprobe inside the memory allocator. Both scenarios can lead to
deadlocks. The deadlock prevention is per CPU by incrementing a per CPU
variable which temporarily blocks the invocation of BPF programs from perf
and kprobes.
Replace the open coded preempt_disable/enable() and this_cpu_inc/dec()
pairs with the new recursion prevention helpers to prepare BPF to work on
PREEMPT_RT enabled kernels. On a non-RT kernel the migrate disable/enable
in the helpers map to preempt_disable/enable(), i.e. no functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145644.211208533@linutronix.de
Instead of preemption disable/enable to reflect the purpose. This allows
PREEMPT_RT to substitute it with an actual migration disable
implementation. On non RT kernels this is still mapped to
preempt_disable/enable().
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.891428873@linutronix.de
All of these cases are strictly of the form:
preempt_disable();
BPF_PROG_RUN(...);
preempt_enable();
Replace this with bpf_prog_run_pin_on_cpu() which wraps BPF_PROG_RUN()
with:
migrate_disable();
BPF_PROG_RUN(...);
migrate_enable();
On non RT enabled kernels this maps to preempt_disable/enable() and on RT
enabled kernels this solely prevents migration, which is sufficient as
there is no requirement to prevent reentrancy to any BPF program from a
preempting task. The only requirement is that the program stays on the same
CPU.
Therefore, this is a trivially correct transformation.
The seccomp loop does not need protection over the loop. It only needs
protection per BPF filter program
[ tglx: Converted to bpf_prog_run_pin_on_cpu() ]
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.691493094@linutronix.de
pcpu_freelist_populate() is disabling interrupts and then iterates over the
possible CPUs. The reason why this disables interrupts is to silence
lockdep because the invoked ___pcpu_freelist_push() takes spin locks.
Neither the interrupt disabling nor the locking are required in this
function because it's called during initialization and the resulting map is
not yet visible to anything.
Split out the actual push assignement into an inline, call it from the loop
and remove the interrupt disable.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.365930116@linutronix.de
If an element is freed via RCU then recursion into BPF instrumentation
functions is not a concern. The element is already detached from the map
and the RCU callback does not hold any locks on which a kprobe, perf event
or tracepoint attached BPF program could deadlock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.259118710@linutronix.de
The BPF invocation from the perf event overflow handler does not require to
disable preemption because this is called from NMI or at least hard
interrupt context which is already non-preemptible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.151953573@linutronix.de
Similar to __bpf_trace_run this is redundant because __bpf_trace_run() is
invoked from a trace point via __DO_TRACE() which already disables
preemption _before_ invoking any of the functions which are attached to a
trace point.
Remove it and add a cant_sleep() check.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145643.059995527@linutronix.de
trace_call_bpf() no longer disables preemption on its own.
All callers of this function has to do it explicitly.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
All callers are built in. No point to export this.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
__bpf_trace_run() disables preemption around the BPF_PROG_RUN() invocation.
This is redundant because __bpf_trace_run() is invoked from a trace point
via __DO_TRACE() which already disables preemption _before_ invoking any of
the functions which are attached to a trace point.
Remove it and add a cant_sleep() check.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.847220186@linutronix.de
The comment where the bucket lock is acquired says:
/* bpf_map_update_elem() can be called in_irq() */
which is not really helpful and aside of that it does not explain the
subtle details of the hash bucket locks expecially in the context of BPF
and perf, kprobes and tracing.
Add a comment at the top of the file which explains the protection scopes
and the details how potential deadlocks are prevented.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.755793061@linutronix.de
Aside of the general unsafety of run-time map allocation for
instrumentation type programs RT enabled kernels have another constraint:
The instrumentation programs are invoked with preemption disabled, but the
memory allocator spinlocks cannot be acquired in atomic context because
they are converted to 'sleeping' spinlocks on RT.
Therefore enforce map preallocation for these programs types when RT is
enabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.648784007@linutronix.de
The assumption that only programs attached to perf NMI events can deadlock
on memory allocators is wrong. Assume the following simplified callchain:
kmalloc() from regular non BPF context
cache empty
freelist empty
lock(zone->lock);
tracepoint or kprobe
BPF()
update_elem()
lock(bucket)
kmalloc()
cache empty
freelist empty
lock(zone->lock); <- DEADLOCK
There are other ways which do not involve locking to create wreckage:
kmalloc() from regular non BPF context
local_irq_save();
...
obj = slab_first();
kprobe()
BPF()
update_elem()
lock(bucket)
kmalloc()
local_irq_save();
...
obj = slab_first(); <- Same object as above ...
So preallocation _must_ be enforced for all variants of intrusive
instrumentation.
Unfortunately immediate enforcement would break backwards compatibility, so
for now such programs still are allowed to run, but a one time warning is
emitted in dmesg and the verifier emits a warning in the verifier log as
well so developers are made aware about this and can fix their programs
before the enforcement becomes mandatory.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200224145642.540542802@linutronix.de
Rework the flushing of proc to use a list of directory inodes that
need to be flushed.
The list is kept on struct pid not on struct task_struct, as there is
a fixed connection between proc inodes and pids but at least for the
case of de_thread the pid of a task_struct changes.
This removes the dependency on proc_mnt which allows for different
mounts of proc having different mount options even in the same pid
namespace and this allows for the removal of proc_mnt which will
trivially the first mount of proc to honor it's mount options.
This flushing remains an optimization. The functions
pid_delete_dentry and pid_revalidate ensure that ordinary dcache
management will not attempt to use dentries past the point their
respective task has died. When unused the shrinker will
eventually be able to remove these dentries.
There is a case in de_thread where proc_flush_pid can be
called early for a given pid. Which winds up being
safe (if suboptimal) as this is just an optiimization.
Only pid directories are put on the list as the other
per pid files are children of those directories and
d_invalidate on the directory will get them as well.
So that the pid can be used during flushing it's reference count is
taken in release_task and dropped in proc_flush_pid. Further the call
of proc_flush_pid is moved after the tasklist_lock is released in
release_task so that it is certain that the pid has already been
unhashed when flushing it taking place. This removes a small race
where a dentry could recreated.
As struct pid is supposed to be small and I need a per pid lock
I reuse the only lock that currently exists in struct pid the
the wait_pidfd.lock.
The net result is that this adds all of this functionality
with just a little extra list management overhead and
a single extra pointer in struct pid.
v2: Initialize pid->inodes. I somehow failed to get that
initialization into the initial version of the patch. A boot
failure was reported by "kernel test robot <lkp@intel.com>", and
failure to initialize that pid->inodes matches all of the reported
symptoms.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
When domains are imbalanced or overloaded a search of all CPUs on the
target domain is searched and compared with task_numa_compare. In some
circumstances, a candidate is found that is an obvious win.
o A task can move to an idle CPU and an idle CPU is found
o A swap candidate is found that would move to its preferred domain
This patch terminates the search when either condition is met.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-14-mgorman@techsingularity.net
When swapping tasks for NUMA balancing, it is preferred that tasks move
to or remain on their preferred node. When considering an imbalance,
encourage tasks to move to their preferred node and discourage tasks from
moving away from their preferred node.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-13-mgorman@techsingularity.net
Multiple tasks can attempt to select and idle CPU but fail because
numa_migrate_on is already set and the migration fails. Instead of failing,
scan for an alternative idle CPU. select_idle_sibling is not used because
it requires IRQs to be disabled and it ignores numa_migrate_on allowing
multiple tasks to stack. This scan may still fail if there are idle
candidate CPUs due to races but if this occurs, it's best that a task
stay on an available CPU that move to a contended one.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-12-mgorman@techsingularity.net
task_numa_find_cpu() can scan a node multiple times. Minimally it scans to
gather statistics and later to find a suitable target. In some cases, the
second scan will simply pick an idle CPU if the load is not imbalanced.
This patch caches information on an idle core while gathering statistics
and uses it immediately if load is not imbalanced to avoid a second scan
of the node runqueues. Preference is given to an idle core rather than an
idle SMT sibling to avoid packing HT siblings due to linearly scanning the
node cpumask.
As a side-effect, even when the second scan is necessary, the importance
of using select_idle_sibling is much reduced because information on idle
CPUs is cached and can be reused.
Note that this patch actually makes is harder to move to an idle CPU
as multiple tasks can race for the same idle CPU due to a race checking
numa_migrate_on. This is addressed in the next patch.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-11-mgorman@techsingularity.net
Take into account the new runnable_avg signal to classify a group and to
mitigate the volatility of util_avg in face of intensive migration or
new task with random utilization.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: "Dietmar Eggemann <dietmar.eggemann@arm.com>"
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-10-mgorman@techsingularity.net
Now that runnable_load_avg has been removed, we can replace it by a new
signal that will highlight the runnable pressure on a cfs_rq. This signal
track the waiting time of tasks on rq and can help to better define the
state of rqs.
At now, only util_avg is used to define the state of a rq:
A rq with more that around 80% of utilization and more than 1 tasks is
considered as overloaded.
But the util_avg signal of a rq can become temporaly low after that a task
migrated onto another rq which can bias the classification of the rq.
When tasks compete for the same rq, their runnable average signal will be
higher than util_avg as it will include the waiting time and we can use
this signal to better classify cfs_rqs.
The new runnable_avg will track the runnable time of a task which simply
adds the waiting time to the running time. The runnable _avg of cfs_rq
will be the /Sum of se's runnable_avg and the runnable_avg of group entity
will follow the one of the rq similarly to util_avg.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: "Dietmar Eggemann <dietmar.eggemann@arm.com>"
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-9-mgorman@techsingularity.net
Now that runnable_load_avg is no more used, we can remove it to make
space for a new signal.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: "Dietmar Eggemann <dietmar.eggemann@arm.com>"
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-8-mgorman@techsingularity.net
The standard load balancer generally tries to keep the number of running
tasks or idle CPUs balanced between NUMA domains. The NUMA balancer allows
tasks to move if there is spare capacity but this causes a conflict and
utilisation between NUMA nodes gets badly skewed. This patch uses similar
logic between the NUMA balancer and load balancer when deciding if a task
migrating to its preferred node can use an idle CPU.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-7-mgorman@techsingularity.net
Similarly to what has been done for the normal load balancer, we can
replace runnable_load_avg by load_avg in numa load balancing and track the
other statistics like the utilization and the number of running tasks to
get to better view of the current state of a node.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: "Dietmar Eggemann <dietmar.eggemann@arm.com>"
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-6-mgorman@techsingularity.net
The walk through the cgroup hierarchy during the enqueue/dequeue of a task
is split in 2 distinct parts for throttled cfs_rq without any added value
but making code less readable.
Change the code ordering such that everything related to a cfs_rq
(throttled or not) will be done in the same loop.
In addition, the same steps ordering is used when updating a cfs_rq:
- update_load_avg
- update_cfs_group
- update *h_nr_running
This reordering enables the use of h_nr_running in PELT algorithm.
No functional and performance changes are expected and have been noticed
during tests.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: "Dietmar Eggemann <dietmar.eggemann@arm.com>"
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-5-mgorman@techsingularity.net
sched:sched_stick_numa is meant to fire when a task is unable to migrate
to the preferred node but from the trace, it's possibile to tell the
difference between "no CPU found", "migration to idle CPU failed" and
"tasks could not be swapped". Extend the tracepoint accordingly.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
[ Minor edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-4-mgorman@techsingularity.net
sched:sched_stick_numa is meant to fire when a task is unable to migrate
to the preferred node. The case where no candidate CPU could be found is
not traced which is an important gap. The tracepoint is not fired when
the task is not allowed to run on any CPU on the preferred node or the
task is already running on the target CPU but neither are interesting
corner cases.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Phil Auld <pauld@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: https://lore.kernel.org/r/20200224095223.13361-3-mgorman@techsingularity.net
Commit 219ca39427 ("audit: use union for audit_field values since
they are mutually exclusive") combined a number of separate fields in
the audit_field struct into a single union. Generally this worked
just fine because they are generally mutually exclusive.
Unfortunately in audit_data_to_entry() the overlap can be a problem
when a specific error case is triggered that causes the error path
code to attempt to cleanup an audit_field struct and the cleanup
involves attempting to free a stored LSM string (the lsm_str field).
Currently the code always has a non-NULL value in the
audit_field.lsm_str field as the top of the for-loop transfers a
value into audit_field.val (both .lsm_str and .val are part of the
same union); if audit_data_to_entry() fails and the audit_field
struct is specified to contain a LSM string, but the
audit_field.lsm_str has not yet been properly set, the error handling
code will attempt to free the bogus audit_field.lsm_str value that
was set with audit_field.val at the top of the for-loop.
This patch corrects this by ensuring that the audit_field.val is only
set when needed (it is cleared when the audit_field struct is
allocated with kcalloc()). It also corrects a few other issues to
ensure that in case of error the proper error code is returned.
Cc: stable@vger.kernel.org
Fixes: 219ca39427 ("audit: use union for audit_field values since they are mutually exclusive")
Reported-by: syzbot+1f4d90ead370d72e450b@syzkaller.appspotmail.com
Signed-off-by: Paul Moore <paul@paul-moore.com>
fixes:
- The WARN_ON which was put into the MSI setaffinity callback for paranoia
reasons actually triggered via a callchain which escaped when all the
possible ways to reach that code were analyzed.
The proc/irq/$N/*affinity interfaces have a quirk which came in when
ALPHA moved to the generic interface: In case that the written affinity
mask does not contain any online CPU it calls into ALPHAs magic auto
affinity setting code.
A few years later this mechanism was also made available to x86 for no
good reasons and in a way which circumvents all sanity checks for
interrupts which cannot have their affinity set from process context on
X86 due to the way the X86 interrupt delivery works.
It would be possible to make this work properly, but there is no point
in doing so. If the interrupt is not yet started then the affinity
setting has no effect and if it is started already then it is already
assigned to an online CPU so there is no point to randomly move it to
some other CPU. Just return EINVAL as the code has done before that
change forever.
- The new MSI quirk bit in the irq domain flags turned out to be already
occupied, which escaped the author and the reviewers because the already
in use bits were 0,6,2,3,4,5 listed in that order. That bit 6 was simply
overlooked because the ordering was straight forward linear
otherwise. So the new bit ended up being a duplicate. Fix it up by
switching the oddball 6 to the obvious 1.
-----BEGIN PGP SIGNATURE-----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=jvVI
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"Two fixes for the irq core code which are follow ups to the recent MSI
fixes:
- The WARN_ON which was put into the MSI setaffinity callback for
paranoia reasons actually triggered via a callchain which escaped
when all the possible ways to reach that code were analyzed.
The proc/irq/$N/*affinity interfaces have a quirk which came in
when ALPHA moved to the generic interface: In case that the written
affinity mask does not contain any online CPU it calls into ALPHAs
magic auto affinity setting code.
A few years later this mechanism was also made available to x86 for
no good reasons and in a way which circumvents all sanity checks
for interrupts which cannot have their affinity set from process
context on X86 due to the way the X86 interrupt delivery works.
It would be possible to make this work properly, but there is no
point in doing so. If the interrupt is not yet started then the
affinity setting has no effect and if it is started already then it
is already assigned to an online CPU so there is no point to
randomly move it to some other CPU. Just return EINVAL as the code
has done before that change forever.
- The new MSI quirk bit in the irq domain flags turned out to be
already occupied, which escaped the author and the reviewers
because the already in use bits were 0,6,2,3,4,5 listed in that
order.
That bit 6 was simply overlooked because the ordering was straight
forward linear otherwise. So the new bit ended up being a
duplicate.
Fix it up by switching the oddball 6 to the obvious 1"
* tag 'irq-urgent-2020-02-22' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/irqdomain: Make sure all irq domain flags are distinct
genirq/proc: Reject invalid affinity masks (again)
- Remove ieee_emulation_warnings sysctl which is a dead code.
- Avoid triggering rebuild of the kernel during make install.
- Enable protected virtualization guest support in default configs.
- Fix cio_ignore seq_file .next function to increase position index. And
use kobj_to_dev instead of container_of in cio code.
- Fix storage block address lists to contain absolute addresses in
qdio code.
- Few clang warnings and spelling fixes.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAl5RI0sACgkQjYWKoQLX
FBig0Af/bJjFspbGFN+YEO+XM3AbURu0lHxq25r0EoSEc9acfS5nMrUk7OhNktND
w+m/PoyOg8elB3LDkalz9IP6CZANSSoGV5aKyg3Wp06Wu//DdwAMJWqFOyosJ89z
zVOSGgX3zHFarodS4suDPTEdDEcSMVVvqnz1A81dQD9QNWyVCutqYABj3OEittOD
EBYchT7Qs/ObwbP+RaUa0swbrq11P8hZSAblbjkbuFpw45CdQ6rFoyJO1Tccuyh7
puNlPLpkDI15RNxC+vh+4NItcxPcIL+Qa0kltbQJLq7aq/UqLNF02vLjWluH4hG6
i6+ZzsIra5gdtdf2cPFiKo7EagpQ2w==
=CRBt
-----END PGP SIGNATURE-----
Merge tag 's390-5.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 fixes from Vasily Gorbik:
- Remove ieee_emulation_warnings sysctl which is a dead code.
- Avoid triggering rebuild of the kernel during make install.
- Enable protected virtualization guest support in default configs.
- Fix cio_ignore seq_file .next function to increase position index.
And use kobj_to_dev instead of container_of in cio code.
- Fix storage block address lists to contain absolute addresses in qdio
code.
- Few clang warnings and spelling fixes.
* tag 's390-5.6-4' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux:
s390/qdio: fill SBALEs with absolute addresses
s390/qdio: fill SL with absolute addresses
s390: remove obsolete ieee_emulation_warnings
s390: make 'install' not depend on vmlinux
s390/kaslr: Fix casts in get_random
s390/mm: Explicitly compare PAGE_DEFAULT_KEY against zero in storage_key_init_range
s390/pkey/zcrypt: spelling s/crytp/crypt/
s390/cio: use kobj_to_dev() API
s390/defconfig: enable CONFIG_PROTECTED_VIRTUALIZATION_GUEST
s390/cio: cio_ignore_proc_seq_next should increase position index
According to Geert's report[0],
kernel/padata.c: warning: 'err' may be used uninitialized in this
function [-Wuninitialized]: => 539:2
Warning is seen only with older compilers on certain archs. The
runtime effect is potentially returning garbage down the stack when
padata's cpumasks are modified before any pcrypt requests have run.
Simplest fix is to initialize err to the success value.
[0] http://lkml.kernel.org/r/20200210135506.11536-1-geert@linux-m68k.org
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: bbefa1dd6a ("crypto: pcrypt - Avoid deadlock by using per-instance padata queues")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-02-21
The following pull-request contains BPF updates for your *net-next* tree.
We've added 25 non-merge commits during the last 4 day(s) which contain
a total of 33 files changed, 2433 insertions(+), 161 deletions(-).
The main changes are:
1) Allow for adding TCP listen sockets into sock_map/hash so they can be used
with reuseport BPF programs, from Jakub Sitnicki.
2) Add a new bpf_program__set_attach_target() helper for adding libbpf support
to specify the tracepoint/function dynamically, from Eelco Chaudron.
3) Add bpf_read_branch_records() BPF helper which helps use cases like profile
guided optimizations, from Daniel Xu.
4) Enable bpf_perf_event_read_value() in all tracing programs, from Song Liu.
5) Relax BTF mandatory check if only used for libbpf itself e.g. to process
BTF defined maps, from Andrii Nakryiko.
6) Move BPF selftests -mcpu compilation attribute from 'probe' to 'v3' as it has
been observed that former fails in envs with low memlock, from Yonghong Song.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 736b46027e ("net: Add ID (if needed) to sock_reuseport and expose
reuseport_lock") has introduced lazy generation of reuseport group IDs that
survive group resize.
By comparing the identifier we check if BPF reuseport program is not trying
to select a socket from a BPF map that belongs to a different reuseport
group than the one the packet is for.
Because SOCKARRAY used to be the only BPF map type that can be used with
reuseport BPF, it was possible to delay the generation of reuseport group
ID until a socket from the group was inserted into BPF map for the first
time.
Now that SOCK{MAP,HASH} can be used with reuseport BPF we have two options,
either generate the reuseport ID on map update, like SOCKARRAY does, or
allocate an ID from the start when reuseport group gets created.
This patch takes the latter approach to keep sockmap free of calls into
reuseport code. This streamlines the reuseport_id access as its lifetime
now matches the longevity of reuseport object.
The cost of this simplification, however, is that we allocate reuseport IDs
for all SO_REUSEPORT users. Even those that don't use SOCKARRAY in their
setups. With the way identifiers are currently generated, we can have at
most S32_MAX reuseport groups, which hopefully is sufficient. If we ever
get close to the limit, we can switch an u64 counter like sk_cookie.
Another change is that we now always call into SOCKARRAY logic to unlink
the socket from the map when unhashing or closing the socket. Previously we
did it only when at least one socket from the group was in a BPF map.
It is worth noting that this doesn't conflict with sockmap tear-down in
case a socket is in a SOCK{MAP,HASH} and belongs to a reuseport
group. sockmap tear-down happens first:
prot->unhash
`- tcp_bpf_unhash
|- tcp_bpf_remove
| `- while (sk_psock_link_pop(psock))
| `- sk_psock_unlink
| `- sock_map_delete_from_link
| `- __sock_map_delete
| `- sock_map_unref
| `- sk_psock_put
| `- sk_psock_drop
| `- rcu_assign_sk_user_data(sk, NULL)
`- inet_unhash
`- reuseport_detach_sock
`- bpf_sk_reuseport_detach
`- WRITE_ONCE(sk->sk_user_data, NULL)
Suggested-by: Martin Lau <kafai@fb.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200218171023.844439-10-jakub@cloudflare.com
SOCKMAP & SOCKHASH now support storing references to listening
sockets. Nothing keeps us from using these map types a collection of
sockets to select from in BPF reuseport programs. Whitelist the map types
with the bpf_sk_select_reuseport helper.
The restriction that the socket has to be a member of a reuseport group
still applies. Sockets in SOCKMAP/SOCKHASH that don't have sk_reuseport_cb
set are not a valid target and we signal it with -EINVAL.
The main benefit from this change is that, in contrast to
REUSEPORT_SOCKARRAY, SOCK{MAP,HASH} don't impose a restriction that a
listening socket can be just one BPF map at the same time.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200218171023.844439-9-jakub@cloudflare.com
Pull networking fixes from David Miller:
1) Limit xt_hashlimit hash table size to avoid OOM or hung tasks, from
Cong Wang.
2) Fix deadlock in xsk by publishing global consumer pointers when NAPI
is finished, from Magnus Karlsson.
3) Set table field properly to RT_TABLE_COMPAT when necessary, from
Jethro Beekman.
4) NLA_STRING attributes are not necessary NULL terminated, deal wiht
that in IFLA_ALT_IFNAME. From Eric Dumazet.
5) Fix checksum handling in atlantic driver, from Dmitry Bezrukov.
6) Handle mtu==0 devices properly in wireguard, from Jason A.
Donenfeld.
7) Fix several lockdep warnings in bonding, from Taehee Yoo.
8) Fix cls_flower port blocking, from Jason Baron.
9) Sanitize internal map names in libbpf, from Toke Høiland-Jørgensen.
10) Fix RDMA race in qede driver, from Michal Kalderon.
11) Fix several false lockdep warnings by adding conditions to
list_for_each_entry_rcu(), from Madhuparna Bhowmik.
12) Fix sleep in atomic in mlx5 driver, from Huy Nguyen.
13) Fix potential deadlock in bpf_map_do_batch(), from Yonghong Song.
14) Hey, variables declared in switch statement before any case
statements are not initialized. I learn something every day. Get
rids of this stuff in several parts of the networking, from Kees
Cook.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (99 commits)
bnxt_en: Issue PCIe FLR in kdump kernel to cleanup pending DMAs.
bnxt_en: Improve device shutdown method.
net: netlink: cap max groups which will be considered in netlink_bind()
net: thunderx: workaround BGX TX Underflow issue
ionic: fix fw_status read
net: disable BRIDGE_NETFILTER by default
net: macb: Properly handle phylink on at91rm9200
s390/qeth: fix off-by-one in RX copybreak check
s390/qeth: don't warn for napi with 0 budget
s390/qeth: vnicc Fix EOPNOTSUPP precedence
openvswitch: Distribute switch variables for initialization
net: ip6_gre: Distribute switch variables for initialization
net: core: Distribute switch variables for initialization
udp: rehash on disconnect
net/tls: Fix to avoid gettig invalid tls record
bpf: Fix a potential deadlock with bpf_map_do_batch
bpf: Do not grab the bucket spinlock by default on htab batch ops
ice: Wait for VF to be reset/ready before configuration
ice: Don't tell the OS that link is going down
ice: Don't reject odd values of usecs set by user
...
No users remain, so kill these off before we grow new ones.
Link: http://lkml.kernel.org/r/20200110154232.4104492-3-arnd@arndb.de
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, if rcu_barrier() returns too soon, the test waits 100ms and
then does another instance of the test. However, if rcu_barrier() were
to have waited for more than 100ms too short a time, this could cause
the test's rcu_head structures to be reused while they were still on
RCU's callback lists. This can result in knock-on errors that obscure
the original rcu_barrier() test failure.
This commit therefore adds code that attempts to wait until all of
the test's callbacks have been invoked. Of course, if RCU completely
lost track of the corresponding rcu_head structures, this wait could be
forever. This commit therefore also complains if this attempted recovery
takes more than one second, and it also gives up when the test ends.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, rcu_torture_barrier_cbs() posts callbacks from whatever CPU
it is running on, which means that all these kthreads might well be
posting from the same CPU, which would drastically reduce the effectiveness
of this test. This commit therefore uses IPIs to make the callbacks be
posted from the corresponding CPU (given by local variable myid).
If the IPI fails (which can happen if the target CPU is offline or does
not exist at all), the callback is posted on whatever CPU is currently
running.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
During changes to kfree_rcu() code, we often check the amount of free
memory. As an alternative to checking this manually, this commit adds a
measurement in the test itself. It measures four times during the test
for available memory, digitally filters these measurements to produce a
running average with a weight of 0.5, and compares this digitally filtered
value with the amount of available memory at the beginning of the test.
Something like the following is printed at the end of the run:
Total time taken by all kfree'ers: 6369738407 ns, loops: 10000, batches: 764, memory footprint: 216MB
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcutorture global variable rcu_torture_current is accessed locklessly,
so it must use the RCU pointer load/store primitives. This commit
therefore adds several that were missed.
This data race was reported by KCSAN. Not appropriate for backporting due
to failure being unlikely and due to this being used only by rcutorture.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcutorture rcu_torture_count and rcu_torture_batch per-CPU variables
are read locklessly, so this commit adds the READ_ONCE() to a load in
order to avoid various types of compiler vandalism^Woptimization.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely and due to this being rcutorture.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_fwd_cb_nodelay variable suppresses excessively long read-side
delays while carrying out an rcutorture forward-progress test. As such,
it is accessed both by readers and updaters, and most of the accesses
therefore use *_ONCE(). Except for one in rcu_read_delay(), which this
commit fixes.
This data race was reported by KCSAN. Not appropriate for backporting
due to this being rcutorture.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The ->rtort_pipe_count field in the rcu_torture structure checks for
too-short grace periods, and is therefore read by rcutorture's readers
while being updated by rcutorture's writers. This commit therefore
adds the needed READ_ONCE() and WRITE_ONCE() invocations.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely and due to this being rcutorture.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In theory, RCU-hotplug operations are supposed to work as soon as there
is more than one CPU online. However, in practice, in normal production
there is no way to make them happen until userspace is up and running.
Besides which, on smaller systems, rcutorture doesn't start doing hotplug
operations until 30 seconds after the start of boot, which on most
systems also means the better part of 30 seconds after the end of boot.
This commit therefore provides a new torture.disable_onoff_at_boot kernel
boot parameter that suppresses CPU-hotplug torture operations until
about the time that init is spawned.
Of course, if you know of a need for boottime CPU-hotplug operations,
then you should avoid passing this argument to any of the torture tests.
You might also want to look at the splats linked to below.
Link: https://lore.kernel.org/lkml/20191206185208.GA25636@paulmck-ThinkPad-P72/
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In normal production, an excessively long wait on a grace period
(synchronize_rcu(), for example) at boottime is often just as bad
as at any other time. In fact, given the desire for fast boot, any
sort of long wait at boot is a bad idea. However, heavy rcutorture
testing on large hyperthreaded systems can generate such long waits
during boot as a matter of course. This commit therefore causes
the rcupdate.rcu_cpu_stall_suppress_at_boot kernel boot parameter to
suppress reporting of bootime bad-sequence warning due to excessively
long grace-period waits.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In normal production, an RCU CPU stall warning at boottime is often
just as bad as at any other time. In fact, given the desire for fast
boot, any sort of long-term stall at boot is a bad idea. However,
heavy rcutorture testing on large hyperthreaded systems can generate
boottime RCU CPU stalls as a matter of course. This commit therefore
provides a kernel boot parameter that suppresses reporting of boottime
RCU CPU stall warnings and similarly of rcutorture writer stalls.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
During boot, CPU hotplug is often disabled, for example by PCI probing.
On large systems that take substantial time to boot, this can result
in spurious RCU_HOTPLUG errors. This commit therefore forgives any
boottime -EBUSY CPU-hotplug failures by adjusting counters to pretend
that the corresponding attempt never happened. A non-splat record
of the failed attempt is emitted to the console with the added string
"(-EBUSY forgiven during boot)".
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Additional rcutorture aggression can result in, believe it or not,
boot times in excess of three minutes on large hyperthreaded systems.
This is long enough for rcutorture to decide to do some callback flooding,
which seems a bit excessive given that userspace cannot have started
until long after boot, and it is userspace that does the real-world
callback flooding. Worse yet, because Tiny RCU lacks forward-progress
functionality, the looping-in-the-kernel tests can also be problematic
during early boot.
This commit therefore causes rcutorture to hold off on callback
flooding until about the time that init is spawned, and the same
for looping-in-the-kernel tests for Tiny RCU.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Some larger systems can take in excess of 50 seconds to complete their
early boot initcalls prior to spawing init. This does not in any way
help the forward-progress judgments of built-in rcutorture (when
rcutorture is built as a module, the insmod or modprobe command normally
cannot happen until some time after boot completes). This commit
therefore suppresses such complaints until about the time that init
is spawned.
This also includes a fix to a stupid error located by kbuild test robot.
[ paulmck: Apply kbuild test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Fix to nohz_full slow-expediting recovery logic, per bpetkov. ]
[ paulmck: Restrict splat to CONFIG_PREEMPT_RT=y kernels and simplify. ]
Tested-by: Borislav Petkov <bp@alien8.de>
A read of the srcu_struct structure's ->srcu_gp_seq field should not
need READ_ONCE() when that structure's ->lock is held. Except that this
lock is not always held when updating this field. This commit therefore
acquires the lock around updates and removes a now-unneeded READ_ONCE().
This data race was reported by KCSAN.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Switch from READ_ONCE() to lock per Peter Zilstra question. ]
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
The srcu_struct structure's ->srcu_idx field is accessed locklessly,
so reads must use READ_ONCE(). This commit therefore adds the needed
READ_ONCE() invocation where it was missed.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The srcu_struct structure's ->srcu_gp_seq_needed_exp field is accessed
locklessly, so updates must use WRITE_ONCE(). This commit therefore
adds the needed WRITE_ONCE() invocations.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The srcu_node structure's ->srcu_gp_seq_needed_exp field is accessed
locklessly, so updates must use WRITE_ONCE(). This commit therefore
adds the needed WRITE_ONCE() invocations.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Sparse reports a warning at exit_tasks_rcu_finish(void)
|warning: context imbalance in exit_tasks_rcu_finish()
|- wrong count at exit
To fix this, this commit adds a __releases(&tasks_rcu_exit_srcu).
Given that exit_tasks_rcu_finish() does actually call __srcu_read_lock(),
this not only fixes the warning but also improves on the readability of
the code.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Sparse reports a warning at exit_tasks_rcu_start(void)
|warning: context imbalance in exit_tasks_rcu_start() - wrong count at exit
To fix this, this commit adds an __acquires(&tasks_rcu_exit_srcu).
Given that exit_tasks_rcu_start() does actually call __srcu_read_lock(),
this not only fixes the warning but also improves on the readability of
the code.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The RCU tasks list of callbacks, rcu_tasks_cbs_head, is sampled locklessly
by rcu_tasks_kthread() when waiting for work to do. This commit therefore
applies READ_ONCE() to that lockless sampling and WRITE_ONCE() to the
single potential store outside of rcu_tasks_kthread.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The __call_rcu() function's header comment refers to a cpu argument
that no longer exists, and the comment of the return path from
rcu_nocb_try_bypass() ignores the non-no-CBs CPU case. This commit
therefore update both comments.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit fixes a spelling mistake in a pr_info() message.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
RCU priority boosting currently is not applied until the grace period
is at least 250 milliseconds old (or the number of milliseconds specified
by the CONFIG_RCU_BOOST_DELAY Kconfig option). Although this has worked
well, it can result in OOM under conditions of RCU callback flooding.
One can argue that the real-time systems using RCU priority boosting
should carefully avoid RCU callback flooding, but one can just as well
argue that an OOM is a rather obnoxious error message.
This commit therefore disables the RCU priority boosting delay when
there are excessive numbers of callbacks queued.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In default configutions, RCU currently waits at least 100 milliseconds
before asking cond_resched() and/or resched_rcu() for help seeking
quiescent states to end a grace period. But 100 milliseconds can be
one good long time during an RCU callback flood, for example, as can
happen when user processes repeatedly open and close files in a tight
loop. These 100-millisecond gaps in successive grace periods during a
callback flood can result in excessive numbers of callbacks piling up,
unnecessarily increasing memory footprint.
This commit therefore asks cond_resched() and/or resched_rcu() for help
as early as the first FQS scan when at least one of the CPUs has more
than 20,000 callbacks queued, a number that can be changed using the new
rcutree.qovld kernel boot parameter. An auxiliary qovld_calc variable
is used to avoid acquisition of locks that have not yet been initialized.
Early tests indicate that this reduces the RCU-callback memory footprint
during rcutorture floods by from 50% to 4x, depending on configuration.
Reported-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reported-by: Tejun Heo <tj@kernel.org>
[ paulmck: Fix bug located by Qian Cai. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tested-by: Dexuan Cui <decui@microsoft.com>
Tested-by: Qian Cai <cai@lca.pw>
The rcu_data structure's ->core_needs_qs field does not necessarily get
cleared in a timely fashion after the corresponding CPUs' quiescent state
has been reported. From a functional viewpoint, no harm done, but this
can result in excessive invocation of RCU core processing, as witnessed
by the kernel test robot, which saw greatly increased softirq overhead.
This commit therefore restores the rcu_report_qs_rdp() function's
clearing of this field, but only when running on the corresponding CPU.
Cases where some other CPU reports the quiescent state (for example, on
behalf of an idle CPU) are handled by setting this field appropriately
within the __note_gp_changes() function's end-of-grace-period checks.
This handling is carried out regardless of whether the end of a grace
period actually happened, thus handling the case where a CPU goes non-idle
after a quiescent state is reported on its behalf, but before the grace
period ends. This fix also avoids cross-CPU updates to ->core_needs_qs,
While in the area, this commit changes the __note_gp_changes() need_gp
variable's name to need_qs because it is a quiescent state that is needed
from the CPU in question.
Fixes: ed93dfc6bc ("rcu: Confine ->core_needs_qs accesses to the corresponding CPU")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
If CPU hotplug testing is enabled, a lock might appear to be maximally
unfair just because one of the CPUs was offline almost all the time.
This commit therefore forgives unfairness if CPU hotplug testing was
enabled.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Both lock_torture_writer() and lock_torture_reader() use the "static"
keyword on their DEFINE_TORTURE_RANDOM(rand) declarations, which means
that a single instance of a random-number generator are shared among all
the writers and another is shared among all the readers. Unfortunately,
this random-number generator was not designed for concurrent access.
This commit therefore removes both "static" keywords so that each reader
and each writer gets its own random-number generator.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The __torture_print_stats() function in locktorture.c carefully
initializes local variable "min" to statp[0].n_lock_acquired, but
then compares it to statp[i].n_lock_fail. Given that the .n_lock_fail
field should normally be zero, and given the initialization, it seems
reasonable to display the maximum and minimum number acquisitions
instead of miscomputing the maximum and minimum number of failures.
This commit therefore switches from failures to acquisitions.
And this turns out to be not only a day-zero bug, but entirely my
own fault. I hate it when that happens!
Fixes: 0af3fe1efa ("locktorture: Add a lock-torture kernel module")
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Peter Zijlstra <peterz@infradead.org>
The event is given three parameters, first one is the name
of RCU flavour, second one is the number of elements in array
for free and last one is an address of the array holding
pointers to be freed by the kfree_bulk() function.
To enable the trace event your kernel has to be build with
CONFIG_RCU_TRACE=y, after that it is possible to track the
events using ftrace subsystem.
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The kfree_rcu() logic can be improved further by using kfree_bulk()
interface along with "basic batching support" introduced earlier.
The are at least two advantages of using "bulk" interface:
- in case of large number of kfree_rcu() requests kfree_bulk()
reduces the per-object overhead caused by calling kfree()
per-object.
- reduces the number of cache-misses due to "pointer chasing"
between objects which can be far spread between each other.
This approach defines a new kfree_rcu_bulk_data structure that
stores pointers in an array with a specific size. Number of entries
in that array depends on PAGE_SIZE making kfree_rcu_bulk_data
structure to be exactly one page.
Since it deals with "block-chain" technique there is an extra
need in dynamic allocation when a new block is required. Memory
is allocated with GFP_NOWAIT | __GFP_NOWARN flags, i.e. that
allows to skip direct reclaim under low memory condition to
prevent stalling and fails silently under high memory pressure.
The "emergency path" gets maintained when a system is run out of
memory. In that case objects are linked into regular list.
The "rcuperf" was run to analyze this change in terms of memory
consumption and kfree_bulk() throughput.
1) Testing on the Intel(R) Xeon(R) W-2135 CPU @ 3.70GHz, 12xCPUs
with following parameters:
kfree_loops=200000 kfree_alloc_num=1000 kfree_rcu_test=1 kfree_vary_obj_size=1
dev.2020.01.10a branch
Default / CONFIG_SLAB
53607352517 ns, loops: 200000, batches: 1885, memory footprint: 1248MB
53529637912 ns, loops: 200000, batches: 1921, memory footprint: 1193MB
53570175705 ns, loops: 200000, batches: 1929, memory footprint: 1250MB
Patch / CONFIG_SLAB
23981587315 ns, loops: 200000, batches: 810, memory footprint: 1219MB
23879375281 ns, loops: 200000, batches: 822, memory footprint: 1190MB
24086841707 ns, loops: 200000, batches: 794, memory footprint: 1380MB
Default / CONFIG_SLUB
51291025022 ns, loops: 200000, batches: 1713, memory footprint: 741MB
51278911477 ns, loops: 200000, batches: 1671, memory footprint: 719MB
51256183045 ns, loops: 200000, batches: 1719, memory footprint: 647MB
Patch / CONFIG_SLUB
50709919132 ns, loops: 200000, batches: 1618, memory footprint: 456MB
50736297452 ns, loops: 200000, batches: 1633, memory footprint: 507MB
50660403893 ns, loops: 200000, batches: 1628, memory footprint: 429MB
in case of CONFIG_SLAB there is double increase in performance and
slightly higher memory usage. As for CONFIG_SLUB, the performance
figures are better together with lower memory usage.
2) Testing on the HiKey-960, arm64, 8xCPUs with below parameters:
CONFIG_SLAB=y
kfree_loops=200000 kfree_alloc_num=1000 kfree_rcu_test=1
102898760401 ns, loops: 200000, batches: 5822, memory footprint: 158MB
89947009882 ns, loops: 200000, batches: 6715, memory footprint: 115MB
rcuperf shows approximately ~12% better throughput in case of
using "bulk" interface. The "drain logic" or its RCU callback
does the work faster that leads to better throughput.
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Tested-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, nocb_gp_wait() unconditionally complains if there is a
callback not already associated with a grace period. This assumes that
either there was no such callback initially on the one hand, or that
the rcu_advance_cbs() function assigned all such callbacks to a grace
period on the other. However, in theory there are some situations that
would prevent rcu_advance_cbs() from assigning all of the callbacks.
This commit therefore checks for unassociated callbacks immediately after
rcu_advance_cbs() returns, while the corresponding rcu_node structure's
->lock is still held. If there are unassociated callbacks at that point,
the subsequent WARN_ON_ONCE() is disabled.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The ->nocb_lock lockdep assertion is currently guarded by cpu_online(),
which is incorrect for no-CBs CPUs, whose callback lists must be
protected by ->nocb_lock regardless of whether or not the corresponding
CPU is online. This situation could result in failure to detect bugs
resulting from failing to hold ->nocb_lock for offline CPUs.
This commit therefore removes the cpu_online() guard.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit reworks the atomic_cmpxchg() loop in rcu_eqs_special_set()
to do only the initial read from the current CPU's rcu_data structure's
->dynticks field explicitly. On subsequent passes, this value is instead
retained from the failing atomic_cmpxchg() operation.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Sparse reports warning at rcu_nocb_bypass_unlock()
warning: context imbalance in rcu_nocb_bypass_unlock() - unexpected unlock
The root cause is a missing annotation of rcu_nocb_bypass_unlock()
which causes the warning.
This commit therefore adds the missing __releases(&rdp->nocb_bypass_lock)
annotation.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Boqun Feng <boqun.feng@gmail.com>
Sparse reports warning at rcu_nocb_bypass_lock()
|warning: context imbalance in rcu_nocb_bypass_lock() - wrong count at exit
To fix this, this commit adds an __acquires(&rdp->nocb_bypass_lock).
Given that rcu_nocb_bypass_lock() does actually call raw_spin_lock()
when raw_spin_trylock() fails, this not only fixes the warning but also
improves on the readability of the code.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently rcu_check_gp_start_stall() complains if a grace period takes
too long to start, where "too long" is roughly one RCU CPU stall-warning
interval. This has worked well, but there are some debugging Kconfig
options (such as CONFIG_EFI_PGT_DUMP=y) that can make booting take a
very long time, so much so that the stall-warning interval has expired
before RCU's grace-period kthread has even been spawned.
This commit therefore resets the rcu_state.gp_req_activity and
rcu_state.gp_activity timestamps just before the grace-period kthread
is spawned, and modifies the checks and adds ordering to ensure that
if rcu_check_gp_start_stall() sees that the grace-period kthread
has been spawned, that it will also see the resets applied to the
rcu_state.gp_req_activity and rcu_state.gp_activity timestamps.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
[ paulmck: Fix whitespace issues reported by Qian Cai. ]
Tested-by: Qian Cai <cai@lca.pw>
[ paulmck: Simplify grace-period wakeup check per Steve Rostedt feedback. ]
The rcu_barrier_callback() function does an atomic_dec_and_test(), and
if it is the last CPU to check in, does the required wakeup. Either way,
it does an event trace. Unfortunately, this is susceptible to the
following sequence of events:
o CPU 0 invokes rcu_barrier_callback(), but atomic_dec_and_test()
says that it is not last. But at this point, CPU 0 is delayed,
perhaps due to an NMI, SMI, or vCPU preemption.
o CPU 1 invokes rcu_barrier_callback(), and atomic_dec_and_test()
says that it is last. So CPU 1 traces completion and does
the needed wakeup.
o The awakened rcu_barrier() function does cleanup and releases
rcu_state.barrier_mutex.
o Another CPU now acquires rcu_state.barrier_mutex and starts
another round of rcu_barrier() processing, including updating
rcu_state.barrier_sequence.
o CPU 0 gets its act back together and does its tracing. Except
that rcu_state.barrier_sequence has already been updated, so
its tracing is incorrect and probably quite confusing.
(Wait! Why did this CPU check in twice for one rcu_barrier()
invocation???)
This commit therefore causes rcu_barrier_callback() to take a
snapshot of the value of rcu_state.barrier_sequence before invoking
atomic_dec_and_test(), thus guaranteeing that the event-trace output
is sensible, even if the timing of the event-trace output might still
be confusing. (Wait! Why did the old rcu_barrier() complete before
all of its CPUs checked in???) But being that this is RCU, only so much
confusion can reasonably be eliminated.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely and due to the mild consequences of the
failure, namely a confusing event trace.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_state structure's ->gp_start field is read locklessly, so this
commit adds the WRITE_ONCE() to an update in order to provide proper
documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_segcblist_insert_pend_cbs() function currently (partially)
initializes the rcu_cblist that it pulls callbacks from. However, all
the resulting stores are dead because all callers pass in the address of
an on-stack cblist that is not used afterwards. This commit therefore
removes this pointless initialization.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The timer_pending() function is mostly used in lockless contexts, so
Without proper annotations, KCSAN might detect a data-race [1].
Using hlist_unhashed_lockless() instead of hand-coding it seems
appropriate (as suggested by Paul E. McKenney).
[1]
BUG: KCSAN: data-race in del_timer / detach_if_pending
write to 0xffff88808697d870 of 8 bytes by task 10 on cpu 0:
__hlist_del include/linux/list.h:764 [inline]
detach_timer kernel/time/timer.c:815 [inline]
detach_if_pending+0xcd/0x2d0 kernel/time/timer.c:832
try_to_del_timer_sync+0x60/0xb0 kernel/time/timer.c:1226
del_timer_sync+0x6b/0xa0 kernel/time/timer.c:1365
schedule_timeout+0x2d2/0x6e0 kernel/time/timer.c:1896
rcu_gp_fqs_loop+0x37c/0x580 kernel/rcu/tree.c:1639
rcu_gp_kthread+0x143/0x230 kernel/rcu/tree.c:1799
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
read to 0xffff88808697d870 of 8 bytes by task 12060 on cpu 1:
del_timer+0x3b/0xb0 kernel/time/timer.c:1198
sk_stop_timer+0x25/0x60 net/core/sock.c:2845
inet_csk_clear_xmit_timers+0x69/0xa0 net/ipv4/inet_connection_sock.c:523
tcp_clear_xmit_timers include/net/tcp.h:606 [inline]
tcp_v4_destroy_sock+0xa3/0x3f0 net/ipv4/tcp_ipv4.c:2096
inet_csk_destroy_sock+0xf4/0x250 net/ipv4/inet_connection_sock.c:836
tcp_close+0x6f3/0x970 net/ipv4/tcp.c:2497
inet_release+0x86/0x100 net/ipv4/af_inet.c:427
__sock_release+0x85/0x160 net/socket.c:590
sock_close+0x24/0x30 net/socket.c:1268
__fput+0x1e1/0x520 fs/file_table.c:280
____fput+0x1f/0x30 fs/file_table.c:313
task_work_run+0xf6/0x130 kernel/task_work.c:113
tracehook_notify_resume include/linux/tracehook.h:188 [inline]
exit_to_usermode_loop+0x2b4/0x2c0 arch/x86/entry/common.c:163
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 12060 Comm: syz-executor.5 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine,
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
[ paulmck: Pulled in Eric's later amendments. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_node structure's ->boost_kthread_status field is accessed
locklessly, so this commit causes all updates to use WRITE_ONCE() and
all reads to use READ_ONCE().
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_data structure's ->rcu_forced_tick field is read locklessly, so
this commit adds WRITE_ONCE() to all updates and READ_ONCE() to all
lockless reads.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_data structure's ->gpwrap field is read locklessly, and so
this commit adds the required READ_ONCE() to a pair of laods in order
to avoid destructive compiler optimizations.
This data race was reported by KCSAN.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Convert to plural and add a note that this is for Tree RCU.
Signed-off-by: SeongJae Park <sjpark@amazon.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The various RCU structures' ->gp_seq, ->gp_seq_needed, ->gp_req_activity,
and ->gp_activity fields are read locklessly, so they must be updated with
WRITE_ONCE() and, when read locklessly, with READ_ONCE(). This commit makes
these changes.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_segcblist structure's ->tails[] array entries are read
locklessly, so this commit adds the READ_ONCE() to a load in order to
avoid destructive compiler optimizations.
This data race was reported by KCSAN.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rt_mutex structure's ->owner field is read locklessly, so this
commit adds the WRITE_ONCE() to an update in order to provide proper
documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will@kernel.org>
The rcu_state structure's ->qsmaskinitnext field is read locklessly,
so this commit adds the WRITE_ONCE() to an update in order to provide
proper documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely for systems not doing incessant CPU-hotplug
operations.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_state structure's ->gp_req_activity field is read locklessly,
so this commit adds the WRITE_ONCE() to an update in order to provide
proper documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_node structure's ->gp_seq field is read locklessly, so this
commit adds the READ_ONCE() to several loads in order to avoid
destructive compiler optimizations.
This data race was reported by KCSAN. Not appropriate for backporting
because this affects only tracing and warnings.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_node structure's ->exp_seq_rq field is read locklessly, so
this commit adds the WRITE_ONCE() to a load in order to provide proper
documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_node structure's ->qsmask field is read locklessly, so this
commit adds the WRITE_ONCE() to an update in order to provide proper
documentation and READ_ONCE()/WRITE_ONCE() pairing.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds "-g -fno-omit-frame-pointer" to ease interpretation
of KCSAN output, but only for CONFIG_KCSAN=y kerrnels.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_node structure's ->exp_seq_rq field is accessed locklessly, so
updates must use WRITE_ONCE(). This commit therefore adds the needed
WRITE_ONCE() invocation where it was missed.
This data race was reported by KCSAN. Not appropriate for backporting
due to failure being unlikely.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The for_each_leaf_node_cpu_mask() and for_each_leaf_node_possible_cpu()
macros must be invoked only on leaf rcu_node structures. Failing to
abide by this restriction can result in infinite loops on systems with
more than 64 CPUs (or for more than 32 CPUs on 32-bit systems). This
commit therefore adds WARN_ON_ONCE() calls to make misuse of these two
macros easier to debug.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Set CONFIG_BOOT_CONFIG=n by default. This also warns
user if CONFIG_BOOT_CONFIG=n but "bootconfig" is given
in the kernel command line.
Link: http://lkml.kernel.org/r/158220111291.26565.9036889083940367969.stgit@devnote2
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Clear trace_state data structure when starting trace
in __synth_event_trace_start() internal function.
Currently trace_state is initialized only in the
synth_event_trace_start() API, but the trace_state
in synth_event_trace() and synth_event_trace_array()
are on the stack without initialization.
This means those APIs will see wrong parameters and
wil skip closing process in __synth_event_trace_end()
because trace_state->disabled may be !0.
Link: http://lkml.kernel.org/r/158193315899.8868.1781259176894639952.stgit@devnote2
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The tracing seftests checks various aspects of the tracing infrastructure,
and one is filtering. If trace_printk() is active during a self test, it can
cause the filtering to fail, which will disable that part of the trace.
To keep the selftests from failing because of trace_printk() calls,
trace_printk() checks the variable tracing_selftest_running, and if set, it
does not write to the tracing buffer.
As some tracers were registered earlier in boot, the selftest they triggered
would fail because not all the infrastructure was set up for the full
selftest. Thus, some of the tests were post poned to when their
infrastructure was ready (namely file system code). The postpone code did
not set the tracing_seftest_running variable, and could fail if a
trace_printk() was added and executed during their run.
Cc: stable@vger.kernel.org
Fixes: 9afecfbb95 ("tracing: Postpone tracer start-up tests till the system is more robust")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The test code that tests synthetic event creation pushes in as one of its
test fields the current CPU using "smp_processor_id()". As this is just
something to see if the value is correctly passed in, and the actual CPU
used does not matter, use raw_smp_processor_id(), otherwise with debug
preemption enabled, a warning happens as the smp_processor_id() is called
without preemption enabled.
Link: http://lkml.kernel.org/r/20200220162950.35162579@gandalf.local.home
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix a varargs-related bug in print_synth_event() which resulted in
strange output and oopses on 32-bit x86 systems. The problem is that
trace_seq_printf() expects the varargs to match the format string, but
print_synth_event() was always passing u64 values regardless. This
results in unspecified behavior when unpacking with va_arg() in
trace_seq_printf().
Add a function that takes the size into account when calling
trace_seq_printf().
Before:
modprobe-1731 [003] .... 919.039758: gen_synth_test: next_pid_field=777(null)next_comm_field=hula hoops ts_ns=1000000 ts_ms=1000 cpu=3(null)my_string_field=thneed my_int_field=598(null)
After:
insmod-1136 [001] .... 36.634590: gen_synth_test: next_pid_field=777 next_comm_field=hula hoops ts_ns=1000000 ts_ms=1000 cpu=1 my_string_field=thneed my_int_field=598
Link: http://lkml.kernel.org/r/a9b59eb515dbbd7d4abe53b347dccf7a8e285657.1581720155.git.zanussi@kernel.org
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit 7276531d4036('tracing: Consolidate trace() functions')
inadvertently dropped the synth_event_trace() and
synth_event_trace_array() checks that verify the number of values
passed in matches the number of fields in the synthetic event being
traced, so add them back.
Link: http://lkml.kernel.org/r/32819cac708714693669e0dfe10fe9d935e94a16.1581720155.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
synth_event_trace(), synth_event_trace_array() and
__synth_event_add_val() write directly into the trace buffer and need
to take endianness into account, like trace_event_raw_event_synth()
does.
Link: http://lkml.kernel.org/r/2011354355e405af9c9d28abba430d1f5ff7771a.1581720155.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
synth_event_trace() is the varargs version of synth_event_trace_array(),
which takes an array of u64, as do synth_event_add_val() et al.
To not only be consistent with those, but also to address the fact
that synth_event_trace() expects every arg to be of the same type
since it doesn't also pass in e.g. a format string, the caller needs
to make sure all args are of the same type, u64. u64 is used because
it needs to accomodate the largest type available in synthetic events,
which is u64.
This fixes the bug reported by the kernel test robot/Rong Chen.
Link: https://lore.kernel.org/lkml/20200212113444.GS12867@shao2-debian/
Link: http://lkml.kernel.org/r/894c4e955558b521210ee0642ba194a9e603354c.1581720155.git.zanussi@kernel.org
Fixes: 9fe41efaca ("tracing: Add synth event generation test module")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Capacity-awareness in the wake-up path previously involved disabling
wake_affine in certain scenarios. We have just made select_idle_sibling()
capacity-aware, so this isn't needed anymore.
Remove wake_cap() entirely.
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
[Changelog tweaks]
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
[Changelog tweaks]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200206191957.12325-5-valentin.schneider@arm.com
The last remaining user of this macro has just been removed, get rid of it.
Suggested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Quentin Perret <qperret@google.com>
Link: https://lkml.kernel.org/r/20200206191957.12325-4-valentin.schneider@arm.com
SD_BALANCE_WAKE was previously added to lower sched_domain levels on
asymmetric CPU capacity systems by commit:
9ee1cda5ee ("sched/core: Enable SD_BALANCE_WAKE for asymmetric capacity systems")
to enable the use of find_idlest_cpu() and friends to find an appropriate
CPU for tasks.
That responsibility has now been shifted to select_idle_sibling() and
friends, and hence the flag can be removed. Note that this causes
asymmetric CPU capacity systems to no longer enter the slow wakeup path
(find_idlest_cpu()) on wakeups - only on execs and forks (which is aligned
with all other mainline topologies).
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
[Changelog tweaks]
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Quentin Perret <qperret@google.com>
Link: https://lkml.kernel.org/r/20200206191957.12325-3-valentin.schneider@arm.com
Issue
=====
On asymmetric CPU capacity topologies, we currently rely on wake_cap() to
drive select_task_rq_fair() towards either:
- its slow-path (find_idlest_cpu()) if either the previous or
current (waking) CPU has too little capacity for the waking task
- its fast-path (select_idle_sibling()) otherwise
Commit:
3273163c67 ("sched/fair: Let asymmetric CPU configurations balance at wake-up")
points out that this relies on the assumption that "[...]the CPU capacities
within an SD_SHARE_PKG_RESOURCES domain (sd_llc) are homogeneous".
This assumption no longer holds on newer generations of big.LITTLE
systems (DynamIQ), which can accommodate CPUs of different compute capacity
within a single LLC domain. To hopefully paint a better picture, a regular
big.LITTLE topology would look like this:
+---------+ +---------+
| L2 | | L2 |
+----+----+ +----+----+
|CPU0|CPU1| |CPU2|CPU3|
+----+----+ +----+----+
^^^ ^^^
LITTLEs bigs
which would result in the following scheduler topology:
DIE [ ] <- sd_asym_cpucapacity
MC [ ] [ ] <- sd_llc
0 1 2 3
Conversely, a DynamIQ topology could look like:
+-------------------+
| L3 |
+----+----+----+----+
| L2 | L2 | L2 | L2 |
+----+----+----+----+
|CPU0|CPU1|CPU2|CPU3|
+----+----+----+----+
^^^^^ ^^^^^
LITTLEs bigs
which would result in the following scheduler topology:
MC [ ] <- sd_llc, sd_asym_cpucapacity
0 1 2 3
What this means is that, on DynamIQ systems, we could pass the wake_cap()
test (IOW presume the waking task fits on the CPU capacities of some LLC
domain), thus go through select_idle_sibling().
This function operates on an LLC domain, which here spans both bigs and
LITTLEs, so it could very well pick a CPU of too small capacity for the
task, despite there being fitting idle CPUs - it very much depends on the
CPU iteration order, on which we have absolutely no guarantees
capacity-wise.
Implementation
==============
Introduce yet another select_idle_sibling() helper function that takes CPU
capacity into account. The policy is to pick the first idle CPU which is
big enough for the task (task_util * margin < cpu_capacity). If no
idle CPU is big enough, we pick the idle one with the highest capacity.
Unlike other select_idle_sibling() helpers, this one operates on the
sd_asym_cpucapacity sched_domain pointer, which is guaranteed to span all
known CPU capacities in the system. As such, this will work for both
"legacy" big.LITTLE (LITTLEs & bigs split at MC, joined at DIE) and for
newer DynamIQ systems (e.g. LITTLEs and bigs in the same MC domain).
Note that this limits the scope of select_idle_sibling() to
select_idle_capacity() for asymmetric CPU capacity systems - the LLC domain
will not be scanned, and no further heuristic will be applied.
Signed-off-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Quentin Perret <qperret@google.com>
Link: https://lkml.kernel.org/r/20200206191957.12325-2-valentin.schneider@arm.com
Fix a mistake in a variable name in a comment.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Alexei Starovoitov says:
====================
pull-request: bpf 2020-02-19
The following pull-request contains BPF updates for your *net* tree.
We've added 10 non-merge commits during the last 10 day(s) which contain
a total of 10 files changed, 93 insertions(+), 31 deletions(-).
The main changes are:
1) batched bpf hashtab fixes from Brian and Yonghong.
2) various selftests and libbpf fixes.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Grabbing the spinlock for every bucket even if it's empty, was causing
significant perfomance cost when traversing htab maps that have only a
few entries. This patch addresses the issue by checking first the
bucket_cnt, if the bucket has some entries then we go and grab the
spinlock and proceed with the batching.
Tested with a htab of size 50K and different value of populated entries.
Before:
Benchmark Time(ns) CPU(ns)
---------------------------------------------
BM_DumpHashMap/1 2759655 2752033
BM_DumpHashMap/10 2933722 2930825
BM_DumpHashMap/200 3171680 3170265
BM_DumpHashMap/500 3639607 3635511
BM_DumpHashMap/1000 4369008 4364981
BM_DumpHashMap/5k 11171919 11134028
BM_DumpHashMap/20k 69150080 69033496
BM_DumpHashMap/39k 190501036 190226162
After:
Benchmark Time(ns) CPU(ns)
---------------------------------------------
BM_DumpHashMap/1 202707 200109
BM_DumpHashMap/10 213441 210569
BM_DumpHashMap/200 478641 472350
BM_DumpHashMap/500 980061 967102
BM_DumpHashMap/1000 1863835 1839575
BM_DumpHashMap/5k 8961836 8902540
BM_DumpHashMap/20k 69761497 69322756
BM_DumpHashMap/39k 187437830 186551111
Fixes: 057996380a ("bpf: Add batch ops to all htab bpf map")
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200218172552.215077-1-brianvv@google.com
Branch records are a CPU feature that can be configured to record
certain branches that are taken during code execution. This data is
particularly interesting for profile guided optimizations. perf has had
branch record support for a while but the data collection can be a bit
coarse grained.
We (Facebook) have seen in experiments that associating metadata with
branch records can improve results (after postprocessing). We generally
use bpf_probe_read_*() to get metadata out of userspace. That's why bpf
support for branch records is useful.
Aside from this particular use case, having branch data available to bpf
progs can be useful to get stack traces out of userspace applications
that omit frame pointers.
Signed-off-by: Daniel Xu <dxu@dxuuu.xyz>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200218030432.4600-2-dxu@dxuuu.xyz
s390 math emulation was removed with commit 5a79859ae0 ("s390:
remove 31 bit support"), rendering ieee_emulation_warnings useless.
The code still built because it was protected by CONFIG_MATHEMU, which
was no longer selectable.
This patch removes the sysctl_ieee_emulation_warnings declaration and
the sysctl entry declaration.
Link: https://lkml.kernel.org/r/20200214172628.3598516-1-steve@sk2.org
Reviewed-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Stephen Kitt <steve@sk2.org>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
- give command line cma= precedence over the CONFIG_ option
(Nicolas Saenz Julienne)
- always allow 32-bit DMA, even for weirdly placed ZONE_DMA
- improve the debug printks when memory is not addressable, to help
find problems with swiotlb initialization
-----BEGIN PGP SIGNATURE-----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=NfNc
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.6' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
- give command line cma= precedence over the CONFIG_ option (Nicolas
Saenz Julienne)
- always allow 32-bit DMA, even for weirdly placed ZONE_DMA
- improve the debug printks when memory is not addressable, to help
find problems with swiotlb initialization
* tag 'dma-mapping-5.6' of git://git.infradead.org/users/hch/dma-mapping:
dma-direct: improve DMA mask overflow reporting
dma-direct: improve swiotlb error reporting
dma-direct: relax addressability checks in dma_direct_supported
dma-contiguous: CMA: give precedence to cmdline
bpf_perf_event_read_value() is NMI safe. Enable it for all BPF programs.
This can be used in fentry/fexit to profile BPF program and individual
kernel function with hardware counters.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200214234146.2910011-1-songliubraving@fb.com
CON_CONSDEV flag was historically used to put/keep the preferred console
first in console_drivers list. Where the preferred console is the last
on the command line.
The ordering is important only when opening /dev/console:
+ tty_kopen()
+ tty_lookup_driver()
+ console_device()
The flag was originally an implementation detail. But it was later
made accessible from userspace via /proc/consoles. It was used,
for example, by the tool "showconsole" to show the real tty
accessible via /dev/console, see
https://github.com/bitstreamout/showconsole
Now, the current code sets CON_CONSDEV only for the preferred
console or when a fallback console is added. The flag is not
set when the preferred console is defined on the command line
but it is not registered from some reasons.
Simple solution is to set CON_CONSDEV flag for the first
registered console. It will work most of the time because:
+ Most real consoles have console->device defined.
+ Boot consoles are removed in printk_late_init().
+ unregister_console() moves CON_CONSDEV flag to the next
console.
Clean solution would require checking con->device when the
preferred console is registered and in unregister_console().
Conclusion:
Use the simple solution for now. It is better than the current
state and good enough.
The clean solution is not worth it. It would complicate the already
complicated code without too much gain. Instead the code would deserve
a complete rewrite.
Link: https://lore.kernel.org/r/20200213095133.23176-4-pmladek@suse.com
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
[pmladek@suse.com: Correct reasoning in the commit message, comment update.]
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
In the following circumstances, the rule of selecting the console
corresponding to the last "console=" entry on the command line as
the preferred console (CON_CONSDEV, ie, /dev/console) fails. This
is a specific example, but it could happen with different consoles
that have a similar name aliasing mechanism.
- The kernel command line has both console=tty0 and console=ttyS0
in that order (the latter with speed etc... arguments).
This is common with some cloud setups such as Amazon Linux.
- add_preferred_console is called early to register "uart0". In
our case that happens from acpi_parse_spcr() on arm64 since the
"enable_console" argument is true on that architecture. This causes
"uart0" to become entry 0 of the console_cmdline array.
Now, because of the above, what happens is:
- add_preferred_console is called by the cmdline parsing for tty0
and ttyS0 respectively, thus occupying entries 1 and 2 of the
console_cmdline array (since this happens after ACPI SPCR parsing).
At that point preferred_console is set to 2 as expected.
- When the tty layer kicks in, it will call register_console for tty0.
This will match entry 1 in console_cmdline array. It isn't our
preferred console but because it's our only console at this point,
it will end up "first" in the consoles list.
- When 8250 probes the actual serial port later on, it calls
register_console for ttyS0. At that point the loop in register_console
tries to match it with the entries in the console_cmdline array.
Ideally this should match ttyS0 in entry 2, which is preferred, causing
it to be inserted first and to replace tty0 as CONSDEV. However, 8250
provides a "match" hook in its struct console, and that hook will match
"uart" as an alias to "ttyS". So we match uart0 at entry 0 in the array
which is not the preferred console and will not match entry 2 which is
since we break out of the loop on the first match. As a result,
we don't set CONSDEV and don't insert it first, but second in
the console list.
As a result, we end up with tty0 remaining first in the array, and thus
/dev/console going there instead of the last user specified one which
is ttyS0.
This tentative fix register_console() to scan first for consoles
specified on the command line, and only if none is found, to then
scan for consoles specified by the architecture.
Link: https://lore.kernel.org/r/20200213095133.23176-3-pmladek@suse.com
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
This moves the loop that tries to match a newly registered console
with the command line or add_preferred_console list into a separate
helper, in order to be able to call it multiple times in subsequent
patches.
Link: https://lore.kernel.org/r/20200213095133.23176-2-pmladek@suse.com
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:
struct foo {
int stuff;
struct boo array[];
};
By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.
Also, notice that, dynamic memory allocations won't be affected by
this change:
"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]
This issue was found with the help of Coccinelle.
[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
head is traversed using hlist_for_each_entry_rcu outside an RCU read-side
critical section but under the protection of hash_lock.
Hence, add corresponding lockdep expression to silence false-positive
lockdep warnings, and harden RCU lists.
[ tglx: Removed the macro and put the condition right where it's used ]
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200216074330.GA14025@workstation-portable
When working commit 6dcd5d7a7a, a mistake was noticed by Linus:
schedule_timeout() was called without setting the task state to anything
particular.
It calls the scheduler, but doesn't delay anything, because the task stays
runnable. That happens because sched_submit_work() does nothing for tasks
in TASK_RUNNING state.
That turned out to be the intended behavior. Adding a WARN() is not useful
as the task could be woken up right after setting the state and before
reaching schedule_timeout().
Improve the comment about schedule_timeout() and describe that more
explicitly.
Signed-off-by: Alexander Popov <alex.popov@linux.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200117225900.16340-1-alex.popov@linux.com
Move the time namespace indicator clock mode to the other ones for
consistency sake.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200207124403.656097274@linutronix.de
If the current clocksource is not VDSO capable there is no point in
updating the high resolution parts of the VDSO data.
Replace the architecture specific check with a check for a VDSO capable
clocksource and skip the update if there is none.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200207124403.563379423@linutronix.de
Now that all architectures are converted to use the generic storage the
helpers and conditionals can be removed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200207124403.470699892@linutronix.de
This if guards whether user-space wants a copy of the offload-jited
bytecode and whether this bytecode exists. By erroneously doing a bitwise
AND instead of a logical AND on user- and kernel-space buffer-size can lead
to no data being copied to user-space especially when user-space size is a
power of two and bigger then the kernel-space buffer.
Fixes: fcfb126def ("bpf: add new jited info fields in bpf_dev_offload and bpf_prog_info")
Signed-off-by: Johannes Krude <johannes@krude.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/bpf/20200212193227.GA3769@phlox.h.transitiv.net
All architectures which use the generic VDSO code have their own storage
for the VDSO clock mode. That's pointless and just requires duplicate code.
Provide generic storage for it. The new Kconfig symbol is intermediate and
will be removed once all architectures are converted over.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/20200207124403.028046322@linutronix.de
Pull scheduler fixes from Ingo Molnar:
"Misc fixes all over the place:
- Fix NUMA over-balancing between lightly loaded nodes. This is
fallout of the big load-balancer rewrite.
- Fix the NOHZ remote loadavg update logic, which fixes anomalies
like reported 150 loadavg on mostly idle CPUs.
- Fix XFS performance/scalability
- Fix throttled groups unbound task-execution bug
- Fix PSI procfs boundary condition
- Fix the cpu.uclamp.{min,max} cgroup configuration write checks
- Fix DocBook annotations
- Fix RCU annotations
- Fix overly CPU-intensive housekeeper CPU logic loop on large CPU
counts"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Fix kernel-doc warning in attach_entity_load_avg()
sched/core: Annotate curr pointer in rq with __rcu
sched/psi: Fix OOB write when writing 0 bytes to PSI files
sched/fair: Allow a per-CPU kthread waking a task to stack on the same CPU, to fix XFS performance regression
sched/fair: Prevent unlimited runtime on throttled group
sched/nohz: Optimize get_nohz_timer_target()
sched/uclamp: Reject negative values in cpu_uclamp_write()
sched/fair: Allow a small load imbalance between low utilisation SD_NUMA domains
timers/nohz: Update NOHZ load in remote tick
sched/core: Don't skip remote tick for idle CPUs
Fix three issues related to the handling of wakeup events signaled
through the ACPI SCI while suspended to idle (Rafael Wysocki) and
unexport an internal cpufreq variable (Yangtao Li).
-----BEGIN PGP SIGNATURE-----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=uE2l
-----END PGP SIGNATURE-----
Merge tag 'pm-5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"Fix three issues related to the handling of wakeup events signaled
through the ACPI SCI while suspended to idle (Rafael Wysocki) and
unexport an internal cpufreq variable (Yangtao Li)"
* tag 'pm-5.6-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PM: s2idle: Prevent spurious SCIs from waking up the system
ACPICA: Introduce acpi_any_gpe_status_set()
ACPI: PM: s2idle: Avoid possible race related to the EC GPE
ACPI: EC: Fix flushing of pending work
cpufreq: Make cpufreq_global_kobject static
A few archs (x86, arm, arm64) don't rely anymore on TIF_NOHZ to call
into context tracking on user entry/exit but instead use static keys
(or not) to optimize those calls. Ideally every arch should migrate to
that behaviour in the long run.
Settle a config option to let those archs remove their TIF_NOHZ
definitions.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paulburton@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: David S. Miller <davem@davemloft.net>
Because cpuidle is the only user of the effective constraint coming
from the CPU latency QoS, add #ifdef CONFIG_CPU_IDLE around that code
to avoid building it unnecessarily.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Update the file information comments in include/linux/pm_qos.h
and kernel/power/qos.c by adding titles along with copyright and
authors information to them and changing the qos.c description to
better reflect its contents (outdated information is dropped from
it in particular).
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Drop the PM QoS classes enum including PM_QOS_CPU_DMA_LATENCY,
drop the wrappers around pm_qos_request(), pm_qos_request_active(),
and pm_qos_add/update/remove_request() introduced previously, rename
these functions, respectively, to cpu_latency_qos_limit(),
cpu_latency_qos_request_active(), and
cpu_latency_qos_add/update/remove_request(), and update their
kerneldoc comments. [While at it, drop some useless comments from
these functions.]
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Qian Cai reported that the WARN_ON() in the x86/msi affinity setting code,
which catches cases where the affinity setting is not done on the CPU which
is the current target of the interrupt, triggers during CPU hotplug stress
testing.
It turns out that the warning which was added with the commit addressing
the MSI affinity race unearthed yet another long standing bug.
If user space writes a bogus affinity mask, i.e. it contains no online CPUs,
then it calls irq_select_affinity_usr(). This was introduced for ALPHA in
eee45269b0 ("[PATCH] Alpha: convert to generic irq framework (generic part)")
and subsequently made available for all architectures in
1840475676 ("genirq: Expose default irq affinity mask (take 3)")
which introduced the circumvention of the affinity setting restrictions for
interrupt which cannot be moved in process context.
The whole exercise is bogus in various aspects:
1) If the interrupt is already started up then there is absolutely
no point to honour a bogus interrupt affinity setting from user
space. The interrupt is already assigned to an online CPU and it
does not make any sense to reassign it to some other randomly
chosen online CPU.
2) If the interupt is not yet started up then there is no point
either. A subsequent startup of the interrupt will invoke
irq_setup_affinity() anyway which will chose a valid target CPU.
So the only correct solution is to just return -EINVAL in case user space
wrote an affinity mask which does not contain any online CPUs, except for
ALPHA which has it's own magic sauce for this.
Fixes: 1840475676 ("genirq: Expose default irq affinity mask (take 3)")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Qian Cai <cai@lca.pw>
Link: https://lkml.kernel.org/r/878sl8xdbm.fsf@nanos.tec.linutronix.de
Change the return type of pm_qos_request() to be the same as the
one of pm_qos_read_value() called by it internally and stop exporting
it to modules (because its only caller, cpuidle, is not modular).
Also move the pm_qos_read_value() header away from the CPU latency
QoS API function headers in pm_qos.h (because it technically does
not belong to that API).
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Modify the definitions of the CPU latency QoS trace events to take
one argument (since PM_QOS_CPU_DMA_LATENCY is always passed as the
pm_qos_class argument to them) and update the documentation of them
accordingly (while at it, make it explicitly mention CPU latency QoS
and relocate it after the device PM QoS trace events documentation).
The names and output format of the trace events do not change to
preserve user space compatibility.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
First, rename PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE to
PM_QOS_CPU_LATENCY_DEFAULT_VALUE and update all of the code
referring to it accordingly.
Next, rename cpu_dma_constraints to cpu_latency_constraints, move
the definition of it closer to the functions referring to it and
update all of them accordingly. [While at it, add a comment to mark
the start of the code related to the CPU latency QoS.]
Finally, rename the pm_qos_power_*() family of functions and
pm_qos_power_fops to cpu_latency_qos_*() and cpu_latency_qos_fops,
respectively, and update the definition of cpu_latency_qos_miscdev.
[While at it, update the miscdev interface code start comment.]
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Notice that pm_qos_remove_notifier() is not used at all and the only
caller of pm_qos_add_notifier() is the cpuidle core, which only needs
the PM_QOS_CPU_DMA_LATENCY notifier to invoke wake_up_all_idle_cpus()
upon changes of the PM_QOS_CPU_DMA_LATENCY target value.
First, to ensure that wake_up_all_idle_cpus() will be called
whenever the PM_QOS_CPU_DMA_LATENCY target value changes, modify the
pm_qos_add/update/remove_request() family of functions to check if
the effective constraint for the PM_QOS_CPU_DMA_LATENCY has changed
and call wake_up_all_idle_cpus() directly in that case.
Next, drop the PM_QOS_CPU_DMA_LATENCY notifier from cpuidle as it is
not necessary any more.
Finally, drop both pm_qos_add_notifier() and pm_qos_remove_notifier(),
as they have no callers now, along with cpu_dma_lat_notifier which is
only used by them.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
First, change the definition of struct pm_qos_request so that it
contains a struct pm_qos_constraints pointer (called "qos") instead
of a PM QoS class number (in preparation for dropping the PM QoS
classes concept altogether going forward) and move its definition
(along with the definition of struct pm_qos_flags_request that does
not change) after the definition of struct pm_qos_constraints.
Next, drop the definition of struct pm_qos_object and the null_pm_qos
and cpu_dma_pm_qos variables of that type along with pm_qos_array[]
holding pointers to them and change the code to refer to the
pm_qos_constraints structure directly or to use the new qos pointer
in struct pm_qos_request for that instead of going through
pm_qos_array[] to access it. Also update kerneldoc comments that
mention pm_qos_class to refer to PM_QOS_CPU_DMA_LATENCY directly
instead.
Finally, drop register_pm_qos_misc(), introduce cpu_latency_qos_miscdev
(with the name field set to "cpu_dma_latency") to implement the
CPU latency QoS interface in /dev/ and register it directly from
pm_qos_power_init().
After these changes the notion of PM QoS classes remains only in the
API (in the form of redundant function parameters that are ignored)
and in the definitions of PM QoS trace events.
While at it, some redundant local variables are dropped etc.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Reorder the code to avoid using extra function header declarations
for the pm_qos_power_*() family of functions and drop those
declarations.
Also clean up the internals of those functions to consolidate checks,
avoid using redundant local variables and similar.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
After commit c3082a674f ("PM: QoS: Get rid of unused flags") the
only global PM QoS class in use is PM_QOS_CPU_DMA_LATENCY, so it
does not really make sense to iterate over global QoS classes
anywhere, since there is only one.
Remove iterations over global QoS classes from the code and use
PM_QOS_CPU_DMA_LATENCY as the target class directly where needed.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Move the definition of pm_qos_read_value() before the one of
pm_qos_get_value() and add a kerneldoc comment to it (as it is
not static).
Also replace the BUG() in pm_qos_get_value() with WARN() (to
prevent the kernel from crashing if an unknown PM QoS type is
used by mistake) and drop the comment next to it that is not
necessary any more.
Additionally, drop the unnecessary inline modifier from the header
of pm_qos_set_value().
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
Clean up the pm_qos_update_target() function:
* Update its kerneldoc comment.
* Drop the redundant ret local variable from it.
* Reorder definitions of local variables in it.
* Update a comment in it.
Also update the kerneldoc comment of pm_qos_update_flags() (e.g.
notifiers are not called by it any more) and add one emtpy line
to its body (for more visual clarity).
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
The PM_QOS_SUM QoS type is not used, so drop it along with the
code referring to it in pm_qos_get_value() and the related local
variables in there.
No intentional functional impact.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
The pm_qos_update_request_timeout() function is not called from
anywhere, so drop it along with the work member in struct
pm_qos_request needed by it.
Also drop the useless pm_qos_update_request_timeout trace event
that is only triggered by that function (so it never triggers at
all) and update the trace events documentation accordingly.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
Reviewed-by: Amit Kucheria <amit.kucheria@linaro.org>
Tested-by: Amit Kucheria <amit.kucheria@linaro.org>
This adds support for creating a process in a different cgroup than its
parent. Callers can limit and account processes and threads right from
the moment they are spawned:
- A service manager can directly spawn new services into dedicated
cgroups.
- A process can be directly created in a frozen cgroup and will be
frozen as well.
- The initial accounting jitter experienced by process supervisors and
daemons is eliminated with this.
- Threaded applications or even thread implementations can choose to
create a specific cgroup layout where each thread is spawned
directly into a dedicated cgroup.
This feature is limited to the unified hierarchy. Callers need to pass
a directory file descriptor for the target cgroup. The caller can
choose to pass an O_PATH file descriptor. All usual migration
restrictions apply, i.e. there can be no processes in inner nodes. In
general, creating a process directly in a target cgroup adheres to all
migration restrictions.
One of the biggest advantages of this feature is that CLONE_INTO_GROUP does
not need to grab the write side of the cgroup cgroup_threadgroup_rwsem.
This global lock makes moving tasks/threads around super expensive. With
clone3() this lock is avoided.
Cc: Tejun Heo <tj@kernel.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: cgroups@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add a cgroup_may_write() helper which we can use in the
CLONE_INTO_CGROUP patch series to verify that we can write to the
destination cgroup.
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: cgroups@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This refactors the fork helpers so they can be easily modified in the
next patches. The patch just moves the cgroup threadgroup rwsem grab and
release into the helpers. They don't need to be directly exposed in fork.c.
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: cgroups@vger.kernel.org
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add a helper cgroup_get_from_file(). The helper will be used in
subsequent patches to retrieve a cgroup while holding a reference to the
struct file it was taken from.
Cc: Tejun Heo <tj@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: cgroups@vger.kernel.org
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The core codepaths to check whether a process can be attached to a
cgroup are the same for threads and thread-group leaders. Only a small
piece of code verifying that source and destination cgroup are in the
same domain differentiates the thread permission checking from
thread-group leader permission checking.
Since cgroup_migrate_vet_dst() only matters cgroup2 - it is a noop on
cgroup1 - we can move it out of cgroup_attach_task().
All checks can now be consolidated into a new helper
cgroup_attach_permissions() callable from both cgroup_procs_write() and
cgroup_threads_write().
Cc: Tejun Heo <tj@kernel.org>
Cc: Li Zefan <lizefan@huawei.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: cgroups@vger.kernel.org
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Convert cpuset_hotplug_workfn() into synchronous call for cpu hotplug
path. For memory hotplug path it still gets queued as a work item.
Since cpuset_hotplug_workfn() can be made synchronous for cpu hotplug
path, it is not required to wait for cpuset hotplug while thawing
processes.
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Tejun Heo <tj@kernel.org>
list_for_each_entry_rcu has built-in RCU and lock checking.
Pass cond argument to list_for_each_entry_rcu() to silence
false lockdep warning when CONFIG_PROVE_RCU_LIST is enabled
by default.
Even though the function css_next_child() already checks if
cgroup_mutex or rcu_read_lock() is held using
cgroup_assert_mutex_or_rcu_locked(), there is a need to pass
cond to list_for_each_entry_rcu() to avoid false positive
lockdep warning.
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
css_task_iter stores pointer to head of each iterable list, this dates
back to commit 0f0a2b4fa6 ("cgroup: reorganize css_task_iter") when we
did not store cur_cset. Let us utilize list heads directly in cur_cset
and streamline css_task_iter_advance_css_set a bit. This is no
intentional function change.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
PF_EXITING is set earlier than actual removal from css_set when a task
is exitting. This can confuse cgroup.procs readers who see no PF_EXITING
tasks, however, rmdir is checking against css_set membership so it can
transitionally fail with EBUSY.
Fix this by listing tasks that weren't unlinked from css_set active
lists.
It may happen that other users of the task iterator (without
CSS_TASK_ITER_PROCS) spot a PF_EXITING task before cgroup_exit(). This
is equal to the state before commit c03cd7738a ("cgroup: Include dying
leaders with live threads in PROCS iterations") but it may be reviewed
later.
Reported-by: Suren Baghdasaryan <surenb@google.com>
Fixes: c03cd7738a ("cgroup: Include dying leaders with live threads in PROCS iterations")
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
If seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output:
1) dd bs=1 skip output of each 2nd elements
$ dd if=/sys/fs/cgroup/cgroup.procs bs=8 count=1
2
3
4
5
1+0 records in
1+0 records out
8 bytes copied, 0,000267297 s, 29,9 kB/s
[test@localhost ~]$ dd if=/sys/fs/cgroup/cgroup.procs bs=1 count=8
2
4 <<< NB! 3 was skipped
6 <<< ... and 5 too
8 <<< ... and 7
8+0 records in
8+0 records out
8 bytes copied, 5,2123e-05 s, 153 kB/s
This happen because __cgroup_procs_start() makes an extra
extra cgroup_procs_next() call
2) read after lseek beyond end of file generates whole last line.
3) read after lseek into middle of last line generates
expected rest of last line and unexpected whole line once again.
Additionally patch removes an extra position index changes in
__cgroup_procs_start()
Cc: stable@vger.kernel.orghttps://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.
# mount | grep cgroup
# dd if=/mnt/cgroup.procs bs=1 # normal output
...
1294
1295
1296
1304
1382
584+0 records in
584+0 records out
584 bytes copied
dd: /mnt/cgroup.procs: cannot skip to specified offset
83 <<< generates end of last line
1383 <<< ... and whole last line once again
0+1 records in
0+1 records out
8 bytes copied
dd: /mnt/cgroup.procs: cannot skip to specified offset
1386 <<< generates last line anyway
0+1 records in
0+1 records out
5 bytes copied
https://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
After commit c3082a674f ("PM: QoS: Get rid of unused flags") the
only global PM QoS class in use is PM_QOS_CPU_DMA_LATENCY and the
existing PM QoS debugfs interface has become overly complicated (as
it takes other potentially possible PM QoS classes that are not there
any more into account). It is also not particularly useful (the
"type" of the PM_QOS_CPU_DMA_LATENCY is known, its aggregate value
can be read from /dev/cpu_dma_latency and the number of requests in
the queue does not really matter) and there are no known users
depending on it. Moreover, there are dedicated trace events that
can be used for tracking PM QoS usage with much higher precision.
For these reasons, drop the PM QoS debugfs interface altogether.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Ulf Hansson <ulf.hansson@linaro.org>
- Fix an uninitialized variable
- Fix compile bug to bootconfig userspace tool (in tools directory)
- Suppress some error messages of bootconfig userspace tool
- Remove unneded CONFIG_LIBXBC from bootconfig
- Allocate bootconfig xbc_nodes dynamically.
To ease complaints about taking up static memory at boot up
- Use of parse_args() to parse bootconfig instead of strstr() usage
Prevents issues of double quotes containing the interested string
- Fix missing ring_buffer_nest_end() on synthetic event error path
- Return zero not -EINVAL on soft disabled synthetic event
(soft disabling must be the same as hard disabling, which returns zero)
- Consolidate synthetic event code (remove duplicate code)
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXkMTwRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qnJQAQD5aKiD6jx+zGtLsFTuZMcEGvhhUuJ6
oUaSvhKO3UqezwD/V5avKuuC0wWt//gOWDY+0+4QNjmvn1GLnaNYohs6fg0=
=NLT9
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Various fixes:
- Fix an uninitialized variable
- Fix compile bug to bootconfig userspace tool (in tools directory)
- Suppress some error messages of bootconfig userspace tool
- Remove unneded CONFIG_LIBXBC from bootconfig
- Allocate bootconfig xbc_nodes dynamically. To ease complaints about
taking up static memory at boot up
- Use of parse_args() to parse bootconfig instead of strstr() usage
Prevents issues of double quotes containing the interested string
- Fix missing ring_buffer_nest_end() on synthetic event error path
- Return zero not -EINVAL on soft disabled synthetic event (soft
disabling must be the same as hard disabling, which returns zero)
- Consolidate synthetic event code (remove duplicate code)"
* tag 'trace-v5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Consolidate trace() functions
tracing: Don't return -EINVAL when tracing soft disabled synth events
tracing: Add missing nest end to synth_event_trace_start() error case
tools/bootconfig: Suppress non-error messages
bootconfig: Allocate xbc_nodes array dynamically
bootconfig: Use parse_args() to find bootconfig and '--'
tracing/kprobe: Fix uninitialized variable bug
bootconfig: Remove unneeded CONFIG_LIBXBC
tools/bootconfig: Fix wrong __VA_ARGS__ usage
The low level index is the index in the underlying hardware buffer of
the most recently captured taken branch which is always saved in
branch_entries[0]. It is very useful for reconstructing the call stack.
For example, in Intel LBR call stack mode, the depth of reconstructed
LBR call stack limits to the number of LBR registers. With the low level
index information, perf tool may stitch the stacks of two samples. The
reconstructed LBR call stack can break the HW limitation.
Add a new branch sample type to retrieve low level index of raw branch
records. The low level index is between -1 (unknown) and max depth which
can be retrieved in /sys/devices/cpu/caps/branches.
Only when the new branch sample type is set, the low level index
information is dumped into the PERF_SAMPLE_BRANCH_STACK output.
Perf tool should check the attr.branch_sample_type, and apply the
corresponding format for PERF_SAMPLE_BRANCH_STACK samples.
Otherwise, some user case may be broken. For example, users may parse a
perf.data, which include the new branch sample type, with an old version
perf tool (without the check). Users probably get incorrect information
without any warning.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200127165355.27495-2-kan.liang@linux.intel.com
We are missing this annotation in percpu_down_write(). Correct
this.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lkml.kernel.org/r/20200108013305.7732-1-dave@stgolabs.net
Now that __percpu_up_read() is only ever used from percpu_up_read()
merge them, it's a small function.
Signed-off-by: Davidlohr Bueso <dave@stgolabs.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Link: https://lkml.kernel.org/r/20200131151540.212415454@infradead.org
Remove the now unused RWSEM_OWNER_UNKNOWN hack. This hack breaks
PREEMPT_RT and getting rid of it was the entire motivation for
re-writing the percpu rwsem.
The biggest problem is that it is fundamentally incompatible with any
form of Priority Inheritance, any exclusively held lock must have a
distinct owner.
Requested-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200204092228.GP14946@hirez.programming.kicks-ass.net
The filesystem freezer uses percpu-rwsem in a way that is effectively
write_non_owner() and achieves this with a few horrible hacks that
rely on the rwsem (!percpu) implementation.
When PREEMPT_RT replaces the rwsem implementation with a PI aware
variant this comes apart.
Remove the embedded rwsem and implement it using a waitqueue and an
atomic_t.
- make readers_block an atomic, and use it, with the waitqueue
for a blocking test-and-set write-side.
- have the read-side wait for the 'lock' state to clear.
Have the waiters use FIFO queueing and mark them (reader/writer) with
a new WQ_FLAG. Use a custom wake_function to wake either a single
writer or all readers until a writer.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200204092403.GB14879@hirez.programming.kicks-ass.net
In preparation for removing the embedded rwsem and building a custom
lock, extract the read-trylock primitive.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200131151540.098485539@infradead.org
As preparation to rework __percpu_down_read() move the
__this_cpu_inc() into it.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200131151540.041600199@infradead.org
As preparation for replacing the embedded rwsem, give percpu-rwsem its
own lockdep_map.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200131151539.927625541@infradead.org
Once a lock class is zapped, all the lock chains that include the zapped
class are essentially useless. The lock_chain structure itself can be
reused, but not the corresponding chain_hlocks[] entries. Over time,
we will run out of chain_hlocks entries while there are still plenty
of other lockdep array entries available.
To fix this imbalance, we have to make chain_hlocks entries reusable
just like the others. As the freed chain_hlocks entries are in blocks of
various lengths. A simple bitmap like the one used in the other reusable
lockdep arrays isn't applicable. Instead the chain_hlocks entries are
put into bucketed lists (MAX_CHAIN_BUCKETS) of chain blocks. Bucket 0
is the variable size bucket which houses chain blocks of size larger than
MAX_CHAIN_BUCKETS sorted in decreasing size order. Initially, the whole
array is in one chain block (the primordial chain block) in bucket 0.
The minimum size of a chain block is 2 chain_hlocks entries. That will
be the minimum allocation size. In other word, allocation requests
for one chain_hlocks entry will cause 2-entry block to be returned and
hence 1 entry will be wasted.
Allocation requests for the chain_hlocks are fulfilled first by looking
for chain block of matching size. If not found, the first chain block
from bucket[0] (the largest one) is split. That can cause hlock entries
fragmentation and reduce allocation efficiency if a chain block of size >
MAX_CHAIN_BUCKETS is ever zapped and put back to after the primordial
chain block. So the MAX_CHAIN_BUCKETS must be large enough that this
should seldom happen.
By reusing the chain_hlocks entries, we are able to handle workloads
that add and zap a lot of lock classes without the risk of running out
of chain_hlocks entries as long as the total number of outstanding lock
classes at any time remain within a reasonable limit.
Two new tracking counters, nr_free_chain_hlocks & nr_large_chain_blocks,
are added to track the total number of chain_hlocks entries in the
free bucketed lists and the number of large chain blocks in buckets[0]
respectively. The nr_free_chain_hlocks replaces nr_chain_hlocks.
The nr_large_chain_blocks counter enables to see if we should increase
the number of buckets (MAX_CHAIN_BUCKETS) available so as to avoid to
avoid the fragmentation problem in bucket[0].
An internal nfsd test that ran for more than an hour and kept on
loading and unloading kernel modules could cause the following message
to be displayed.
[ 4318.443670] BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!
The patched kernel was able to complete the test with a lot of free
chain_hlocks entries to spare:
# cat /proc/lockdep_stats
:
dependency chains: 18867 [max: 65536]
dependency chain hlocks: 74926 [max: 327680]
dependency chain hlocks lost: 0
:
zapped classes: 1541
zapped lock chains: 56765
large chain blocks: 1
By changing MAX_CHAIN_BUCKETS to 3 and add a counter for the size of the
largest chain block. The system still worked and We got the following
lockdep_stats data:
dependency chains: 18601 [max: 65536]
dependency chain hlocks used: 73133 [max: 327680]
dependency chain hlocks lost: 0
:
zapped classes: 1541
zapped lock chains: 56702
large chain blocks: 45165
large chain block size: 20165
By running the test again, I was indeed able to cause chain_hlocks
entries to get lost:
dependency chain hlocks used: 74806 [max: 327680]
dependency chain hlocks lost: 575
:
large chain blocks: 48737
large chain block size: 7
Due to the fragmentation, it is possible that the
"MAX_LOCKDEP_CHAIN_HLOCKS too low!" error can happen even if a lot of
of chain_hlocks entries appear to be free.
Fortunately, a MAX_CHAIN_BUCKETS value of 16 should be big enough that
few variable sized chain blocks, other than the initial one, should
ever be present in bucket 0.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-7-longman@redhat.com
Add a new counter nr_zapped_lock_chains to track the number lock chains
that have been removed.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-6-longman@redhat.com
If a lock chain contains a class that is zapped, the whole lock chain is
likely to be invalid. If the zapped class is at the end of the chain,
the partial chain without the zapped class should have been stored
already as the current code will store all its predecessor chains. If
the zapped class is somewhere in the middle, there is no guarantee that
the partial chain will actually happen. It may just clutter up the hash
and make searching slower. I would rather prefer storing the chain only
when it actually happens.
So just dump the corresponding chain_hlocks entries for now. A latter
patch will try to reuse the freed chain_hlocks entries.
This patch also changes the type of nr_chain_hlocks to unsigned integer
to be consistent with the other counters.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-5-longman@redhat.com
The whole point of the lockdep dynamic key patch is to allow unused
locks to be removed from the lockdep data buffers so that existing
buffer space can be reused. However, there is no way to find out how
many unused locks are zapped and so we don't know if the zapping process
is working properly.
Add a new nr_zapped_classes counter to track that and show it in
/proc/lockdep_stats.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-4-longman@redhat.com
Currently, the irq_context field of a lock chains displayed in
/proc/lockdep_chains is just a number. It is likely that many people
may not know what a non-zero number means. To make the information more
useful, print the actual irq names ("softirq" and "hardirq") instead.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-3-longman@redhat.com
There are currently three counters to track the IRQ context of a lock
chain - nr_hardirq_chains, nr_softirq_chains and nr_process_chains.
They are incremented when a new lock chain is added, but they are
not decremented when a lock chain is removed. That causes some of the
statistic counts reported by /proc/lockdep_stats to be incorrect.
IRQ
Fix that by decrementing the right counter when a lock chain is removed.
Since inc_chains() no longer accesses hardirq_context and softirq_context
directly, it is moved out from the CONFIG_TRACE_IRQFLAGS conditional
compilation block.
Fixes: a0b0fd53e1 ("locking/lockdep: Free lock classes that are no longer in use")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200206152408.24165-2-longman@redhat.com
Fix kernel-doc warning in kernel/sched/fair.c, caused by a recent
function parameter removal:
../kernel/sched/fair.c:3526: warning: Excess function parameter 'flags' description in 'attach_entity_load_avg'
Fixes: a4f9a0e51b ("sched/fair: Remove redundant call to cpufreq_update_util()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/cbe964e4-6879-fd08-41c9-ef1917414af4@infradead.org
When CONFIG_PRINTK is disabled (e.g. when building allnoconfig), clang
warns:
../kernel/printk/printk.c:2416:10: warning: 'sprintf' will always
overflow; destination buffer has size 0, but format string expands to at
least 33 [-Wfortify-source]
len = sprintf(text,
^
1 warning generated.
It is not wrong; text has a zero size when CONFIG_PRINTK is disabled
because LOG_LINE_MAX and PREFIX_MAX are both zero. Change to snprintf so
that this case is explicitly handled without any risk of overflow.
Link: https://github.com/ClangBuiltLinux/linux/issues/846
Link: 6d485ff455
Link: http://lkml.kernel.org/r/20200130221644.2273-1-natechancellor@gmail.com
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Cc: clang-built-linux@googlegroups.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Issuing write() with count parameter set to 0 on any file under
/proc/pressure/ will cause an OOB write because of the access to
buf[buf_size-1] when NUL-termination is performed. Fix this by checking
for buf_size to be non-zero.
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/20200203212216.7076-1-surenb@google.com
Some consoles might require special operations on unregistering.
For instance, serial console, when registered in the kernel,
keeps power on for entire time, until it gets unregistered.
Example of use:
->setup(console):
pm_runtime_get(...);
->exit(console):
pm_runtime_put(...);
For such cases to have a balance we would provide ->exit() callback.
Link: http://lkml.kernel.org/r/20200203133130.11591-7-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
If console is not on the list then there is nothing for us to do
and sysfs notify is pointless.
Note, that nr_ext_console_drivers is being changed only for listed
consoles.
Suggested-by: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Link: http://lkml.kernel.org/r/20200203133130.11591-6-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
There are only two callers that use the returned code from
unregister_console():
- unregister_early_console() in arch/m68k/kernel/early_printk.c
- kgdb_unregister_nmi_console() in drivers/tty/serial/kgdb_nmi.c
They both expect to get "0" on success and a non-zero value on error.
But the current behavior is confusing and buggy:
- _braille_unregister_console() returns "1" on success
- unregister_console() returns "1" on error
Fix and clean up the behavior:
- Return success when _braille_unregister_console() succeeded
- Return a meaningful error code when the console was
not registered before
Link: http://lkml.kernel.org/r/20200203133130.11591-5-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
/* find the last or real console */
This comment is misleading. The purpose of the loop is to check
if we are trying to register boot console after a real one has
already been registered. This is already mentioned in a comment
above.
Link: http://lkml.kernel.org/r/20200203133130.11591-4-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Suggested-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
[pmladek@suse.com: Updated commit message.]
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
We have rather open coded single linked list manipulations where we may
simple use for_each_console() helper with properly set exit conditions.
Replace open coded single-linked list handling with for_each_console()
helper in use.
Link: http://lkml.kernel.org/r/20200203133130.11591-3-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
There is no need to explicitly check for console_drivers to be non-NULL
since for_each_console() does this.
Link: http://lkml.kernel.org/r/20200203133130.11591-2-andriy.shevchenko@linux.intel.com
To: linux-kernel@vger.kernel.org
To: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
It is theoretically possible for the ACPI EC GPE to be set after the
s2idle_ops->wake() called from s2idle_loop() has returned and before
the subsequent pm_wakeup_pending() check is carried out. If that
happens, the resulting wakeup event will cause the system to resume
even though it may be a spurious one.
To avoid that race, first make the ->wake() callback in struct
platform_s2idle_ops return a bool value indicating whether or not
to let the system resume and rearrange s2idle_loop() to use that
value instad of the direct pm_wakeup_pending() call if ->wake() is
present.
Next, rework acpi_s2idle_wake() to process EC events and check
pm_wakeup_pending() before re-arming the SCI for system wakeup
to prevent it from triggering prematurely and add comments to
that function to explain the rationale for the new code flow.
Fixes: 56b9918490 ("PM: sleep: Simplify suspend-to-idle control flow")
Cc: 5.4+ <stable@vger.kernel.org> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Move the checking, buffer reserve and buffer commit code in
synth_event_trace_start/end() into inline functions
__synth_event_trace_start/end() so they can also be used by
synth_event_trace() and synth_event_trace_array(), and then have all
those functions use them.
Also, change synth_event_trace_state.enabled to disabled so it only
needs to be set if the event is disabled, which is not normally the
case.
Link: http://lkml.kernel.org/r/b1f3108d0f450e58192955a300e31d0405ab4149.1581374549.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
There's no reason to return -EINVAL when tracing a synthetic event if
it's soft disabled - treat it the same as if it were hard disabled and
return normally.
Have synth_event_trace() and synth_event_trace_array() just return
normally, and have synth_event_trace_start set the trace state to
disabled and return.
Link: http://lkml.kernel.org/r/df5d02a1625aff97c9866506c5bada6a069982ba.1581374549.git.zanussi@kernel.org
Fixes: 8dcc53ad95 ("tracing: Add synth_event_trace() and related functions")
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If the ring_buffer reserve in synth_event_trace_start() fails, the
matching ring_buffer_nest_end() should be called in the error code,
since nothing else will ever call it in this case.
Link: http://lkml.kernel.org/r/20abc444b3eeff76425f895815380abe7aa53ff8.1581374549.git.zanussi@kernel.org
Fixes: 8dcc53ad95 ("tracing: Add synth_event_trace() and related functions")
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull cgroup fix from Tejun Heo:
"I made a mistake while removing cgroup task list lazy init
optimization making the root cgroup.procs show entries for the
init_tasks. The zero entries doesn't cause critical failures but does
make systemd print out warning messages during boot.
Fix it by omitting init_tasks as they should be"
* 'for-5.6-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: init_tasks shouldn't be linked to the root cgroup
Fix the following sparse warning:
kernel/bpf/btf.c:4131:5: warning: symbol 'btf_check_func_type_match' was
not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Hongbo Yao <yaohongbo@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200210011441.147102-1-yaohongbo@huawei.com
There is a potential execution path in which variable *ret* is returned
without being properly initialized, previously.
Fix this by initializing variable *ret* to 0.
Link: http://lkml.kernel.org/r/20200205223404.GA3379@embeddedor
Addresses-Coverity-ID: 1491142 ("Uninitialized scalar variable")
Fixes: 2a588dd1d5 ("tracing: Add kprobe event command generation functions")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Common Criteria calls out for any action that modifies the audit trail to
be recorded. That usually is interpreted to mean insertion or removal of
rules. It is not required to log modification of the inode information
since the watch is still in effect. Additionally, if the rule is a never
rule and the underlying file is one they do not want events for, they
get an event for this bookkeeping update against their wishes.
Since no device/inode info is logged at insertion and no device/inode
information is logged on update, there is nothing meaningful being
communicated to the admin by the CONFIG_CHANGE updated_rules event. One
can assume that the rule was not "modified" because it is still watching
the intended target. If the device or inode cannot be resolved, then
audit_panic is called which is sufficient.
The correct resolution is to drop logging config_update events since
the watch is still in effect but just on another unknown inode.
Signed-off-by: Steve Grubb <sgrubb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
The following XFS commit:
8ab39f11d9 ("xfs: prevent CIL push holdoff in log recovery")
changed the logic from using bound workqueues to using unbound
workqueues. Functionally this makes sense but it was observed at the
time that the dbench performance dropped quite a lot and CPU migrations
were increased.
The current pattern of the task migration is straight-forward. With XFS,
an IO issuer delegates work to xlog_cil_push_work ()on an unbound kworker.
This runs on a nearby CPU and on completion, dbench wakes up on its old CPU
as it is still idle and no migration occurs. dbench then queues the real
IO on the blk_mq_requeue_work() work item which runs on a bound kworker
which is forced to run on the same CPU as dbench. When IO completes,
the bound kworker wakes dbench but as the kworker is a bound but,
real task, the CPU is not considered idle and dbench gets migrated by
select_idle_sibling() to a new CPU. dbench may ping-pong between two CPUs
for a while but ultimately it starts a round-robin of all CPUs sharing
the same LLC. High-frequency migration on each IO completion has poor
performance overall. It has negative implications both in commication
costs and power management. mpstat confirmed that at low thread counts
that all CPUs sharing an LLC has low level of activity.
Note that even if the CIL patch was reverted, there still would
be migrations but the impact is less noticeable. It turns out that
individually the scheduler, XFS, blk-mq and workqueues all made sensible
decisions but in combination, the overall effect was sub-optimal.
This patch special cases the IO issue/completion pattern and allows
a bound kworker waker and a task wakee to stack on the same CPU if
there is a strong chance they are directly related. The expectation
is that the kworker is likely going back to sleep shortly. This is not
guaranteed as the IO could be queued asynchronously but there is a very
strong relationship between the task and kworker in this case that would
justify stacking on the same CPU instead of migrating. There should be
few concerns about kworker starvation given that the special casing is
only when the kworker is the waker.
DBench on XFS
MMTests config: io-dbench4-async modified to run on a fresh XFS filesystem
UMA machine with 8 cores sharing LLC
5.5.0-rc7 5.5.0-rc7
tipsched-20200124 kworkerstack
Amean 1 22.63 ( 0.00%) 20.54 * 9.23%*
Amean 2 25.56 ( 0.00%) 23.40 * 8.44%*
Amean 4 28.63 ( 0.00%) 27.85 * 2.70%*
Amean 8 37.66 ( 0.00%) 37.68 ( -0.05%)
Amean 64 469.47 ( 0.00%) 468.26 ( 0.26%)
Stddev 1 1.00 ( 0.00%) 0.72 ( 28.12%)
Stddev 2 1.62 ( 0.00%) 1.97 ( -21.54%)
Stddev 4 2.53 ( 0.00%) 3.58 ( -41.19%)
Stddev 8 5.30 ( 0.00%) 5.20 ( 1.92%)
Stddev 64 86.36 ( 0.00%) 94.53 ( -9.46%)
NUMA machine, 48 CPUs total, 24 CPUs share cache
5.5.0-rc7 5.5.0-rc7
tipsched-20200124 kworkerstack-v1r2
Amean 1 58.69 ( 0.00%) 30.21 * 48.53%*
Amean 2 60.90 ( 0.00%) 35.29 * 42.05%*
Amean 4 66.77 ( 0.00%) 46.55 * 30.28%*
Amean 8 81.41 ( 0.00%) 68.46 * 15.91%*
Amean 16 113.29 ( 0.00%) 107.79 * 4.85%*
Amean 32 199.10 ( 0.00%) 198.22 * 0.44%*
Amean 64 478.99 ( 0.00%) 477.06 * 0.40%*
Amean 128 1345.26 ( 0.00%) 1372.64 * -2.04%*
Stddev 1 2.64 ( 0.00%) 4.17 ( -58.08%)
Stddev 2 4.35 ( 0.00%) 5.38 ( -23.73%)
Stddev 4 6.77 ( 0.00%) 6.56 ( 3.00%)
Stddev 8 11.61 ( 0.00%) 10.91 ( 6.04%)
Stddev 16 18.63 ( 0.00%) 19.19 ( -3.01%)
Stddev 32 38.71 ( 0.00%) 38.30 ( 1.06%)
Stddev 64 100.28 ( 0.00%) 91.24 ( 9.02%)
Stddev 128 186.87 ( 0.00%) 160.34 ( 14.20%)
Dbench has been modified to report the time to complete a single "load
file". This is a more meaningful metric for dbench that a throughput
metric as the benchmark makes many different system calls that are not
throughput-related
Patch shows a 9.23% and 48.53% reduction in the time to process a load
file with the difference partially explained by the number of CPUs sharing
a LLC. In a separate run, task migrations were almost eliminated by the
patch for low client counts. In case people have issue with the metric
used for the benchmark, this is a comparison of the throughputs as
reported by dbench on the NUMA machine.
dbench4 Throughput (misleading but traditional)
5.5.0-rc7 5.5.0-rc7
tipsched-20200124 kworkerstack-v1r2
Hmean 1 321.41 ( 0.00%) 617.82 * 92.22%*
Hmean 2 622.87 ( 0.00%) 1066.80 * 71.27%*
Hmean 4 1134.56 ( 0.00%) 1623.74 * 43.12%*
Hmean 8 1869.96 ( 0.00%) 2212.67 * 18.33%*
Hmean 16 2673.11 ( 0.00%) 2806.13 * 4.98%*
Hmean 32 3032.74 ( 0.00%) 3039.54 ( 0.22%)
Hmean 64 2514.25 ( 0.00%) 2498.96 * -0.61%*
Hmean 128 1778.49 ( 0.00%) 1746.05 * -1.82%*
Note that this is somewhat specific to XFS and ext4 shows no performance
difference as it does not rely on kworkers in the same way. No major
problem was observed running other workloads on different machines although
not all tests have completed yet.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200128154006.GD3466@techsingularity.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- fix randconfig to generate a sane .config
- rename hostprogs-y / always to hostprogs / always-y, which are
more natual syntax.
- optimize scripts/kallsyms
- fix yes2modconfig and mod2yesconfig
- make multiple directory targets ('make foo/ bar/') work
-----BEGIN PGP SIGNATURE-----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=sv4U
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild updates from Masahiro Yamada:
- fix randconfig to generate a sane .config
- rename hostprogs-y / always to hostprogs / always-y, which are more
natual syntax.
- optimize scripts/kallsyms
- fix yes2modconfig and mod2yesconfig
- make multiple directory targets ('make foo/ bar/') work
* tag 'kbuild-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: make multiple directory targets work
kconfig: Invalidate all symbols after changing to y or m.
kallsyms: fix type of kallsyms_token_table[]
scripts/kallsyms: change table to store (strcut sym_entry *)
scripts/kallsyms: rename local variables in read_symbol()
kbuild: rename hostprogs-y/always to hostprogs/always-y
kbuild: fix the document to use extra-y for vmlinux.lds
kconfig: fix broken dependency in randconfig-generated .config
- Ensure that the PIT is set up when the local APIC is disable or
configured in legacy mode. This is caused by an ordering issue
introduced in the recent changes which skip PIT initialization when the
TSC and APIC frequencies are already known.
- Handle malformed SRAT tables during early ACPI parsing which caused an
infinite loop anda boot hang.
- Fix a long standing race in the affinity setting code which affects PCI
devices with non-maskable MSI interrupts. The problem is caused by the
non-atomic writes of the MSI address (destination APIC id) and data
(vector) fields which the device uses to construct the MSI message. The
non-atomic writes are mandated by PCI.
If both fields change and the device raises an interrupt after writing
address and before writing data, then the MSI block constructs a
inconsistent message which causes interrupts to be lost and subsequent
malfunction of the device.
The fix is to redirect the interrupt to the new vector on the current
CPU first and then switch it over to the new target CPU. This allows to
observe an eventually raised interrupt in the transitional stage (old
CPU, new vector) to be observed in the APIC IRR and retriggered on the
new target CPU and the new vector. The potential spurious interrupts
caused by this are harmless and can in the worst case expose a buggy
driver (all handlers have to be able to deal with spurious interrupts as
they can and do happen for various reasons).
- Add the missing suspend/resume mechanism for the HYPERV hypercall page
which prevents resume hibernation on HYPERV guests. This change got
lost before the merge window.
- Mask the IOAPIC before disabling the local APIC to prevent potentially
stale IOAPIC remote IRR bits which cause stale interrupt lines after
resume.
-----BEGIN PGP SIGNATURE-----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=WxKD
-----END PGP SIGNATURE-----
Merge tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Thomas Gleixner:
"A set of fixes for X86:
- Ensure that the PIT is set up when the local APIC is disable or
configured in legacy mode. This is caused by an ordering issue
introduced in the recent changes which skip PIT initialization when
the TSC and APIC frequencies are already known.
- Handle malformed SRAT tables during early ACPI parsing which caused
an infinite loop anda boot hang.
- Fix a long standing race in the affinity setting code which affects
PCI devices with non-maskable MSI interrupts. The problem is caused
by the non-atomic writes of the MSI address (destination APIC id)
and data (vector) fields which the device uses to construct the MSI
message. The non-atomic writes are mandated by PCI.
If both fields change and the device raises an interrupt after
writing address and before writing data, then the MSI block
constructs a inconsistent message which causes interrupts to be
lost and subsequent malfunction of the device.
The fix is to redirect the interrupt to the new vector on the
current CPU first and then switch it over to the new target CPU.
This allows to observe an eventually raised interrupt in the
transitional stage (old CPU, new vector) to be observed in the APIC
IRR and retriggered on the new target CPU and the new vector.
The potential spurious interrupts caused by this are harmless and
can in the worst case expose a buggy driver (all handlers have to
be able to deal with spurious interrupts as they can and do happen
for various reasons).
- Add the missing suspend/resume mechanism for the HYPERV hypercall
page which prevents resume hibernation on HYPERV guests. This
change got lost before the merge window.
- Mask the IOAPIC before disabling the local APIC to prevent
potentially stale IOAPIC remote IRR bits which cause stale
interrupt lines after resume"
* tag 'x86-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/apic: Mask IOAPIC entries when disabling the local APIC
x86/hyperv: Suspend/resume the hypercall page for hibernation
x86/apic/msi: Plug non-maskable MSI affinity race
x86/boot: Handle malformed SRAT tables during early ACPI parsing
x86/timer: Don't skip PIT setup when APIC is disabled or in legacy mode
- Make the UP version of smp_call_function_single() match SMP semantics
when called for a not available CPU. Instead of emitting a warning and
assuming that the function call target is CPU0, return a proper error
code like the SMP version does.
- Remove a superfluous check in smp_call_function_many_cond()
-----BEGIN PGP SIGNATURE-----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=XfHp
-----END PGP SIGNATURE-----
Merge tag 'smp-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull SMP fixes from Thomas Gleixner:
"Two fixes for the SMP related functionality:
- Make the UP version of smp_call_function_single() match SMP
semantics when called for a not available CPU. Instead of emitting
a warning and assuming that the function call target is CPU0,
return a proper error code like the SMP version does.
- Remove a superfluous check in smp_call_function_many_cond()"
* tag 'smp-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp/up: Make smp_call_function_single() match SMP semantics
smp: Remove superfluous cond_func check in smp_call_function_many_cond()
- Kernel fixes:
- Install cgroup events to the correct CPU context to prevent a
potential list double add
- Prevent am intgeer underflow in the perf mlock acounting
- Add a missing prototyp for arch_perf_update_userpage()
- Tooling:
- Add a missing unlock in the error path of maps__insert() in perf maps.
- Fix the build with the latest libbfd
- Fix the perf parser so it does not delete parse event terms, which
caused a regression for using perf with the ARM CoreSight as the sink
confuguration was missing due to the deletion.
- Fix the double free in the perf CPU map merging test case
- Add the missing ustring support for the perf probe command
-----BEGIN PGP SIGNATURE-----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=xu7D
-----END PGP SIGNATURE-----
Merge tag 'perf-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Thomas Gleixner:
"A set of fixes and improvements for the perf subsystem:
Kernel fixes:
- Install cgroup events to the correct CPU context to prevent a
potential list double add
- Prevent an integer underflow in the perf mlock accounting
- Add a missing prototype for arch_perf_update_userpage()
Tooling:
- Add a missing unlock in the error path of maps__insert() in perf
maps.
- Fix the build with the latest libbfd
- Fix the perf parser so it does not delete parse event terms, which
caused a regression for using perf with the ARM CoreSight as the
sink configuration was missing due to the deletion.
- Fix the double free in the perf CPU map merging test case
- Add the missing ustring support for the perf probe command"
* tag 'perf-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf maps: Add missing unlock to maps__insert() error case
perf probe: Add ustring support for perf probe command
perf: Make perf able to build with latest libbfd
perf test: Fix test case Merge cpu map
perf parse: Copy string to perf_evsel_config_term
perf parse: Refactor 'struct perf_evsel_config_term'
kernel/events: Add a missing prototype for arch_perf_update_userpage()
perf/cgroups: Install cgroup events to correct cpuctx
perf/core: Fix mlock accounting in perf_mmap()
- Handle a subtle race between the clocksource watchdog and a concurrent
clocksource watchdog stop/start sequence correctly to prevent a timer
double add bug.
- Fix the file path for the core time namespace file.
-----BEGIN PGP SIGNATURE-----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=0zFj
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"Two small fixes for the time(r) subsystem:
- Handle a subtle race between the clocksource watchdog and a
concurrent clocksource watchdog stop/start sequence correctly to
prevent a timer double add bug.
- Fix the file path for the core time namespace file"
* tag 'timers-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
clocksource: Prevent double add_timer_on() for watchdog_timer
MAINTAINERS: Correct path to time namespace source file
- Provision only ACPI enabled redistributors on GICv3
- Use the proper command colums when building the INVALL command for the
GICv3-ITS
- Ensure the allocation of the L2 vPE table for GICv4.1
- Correct the GICv4.1 VPROBASER programming so it uses the proper size
- A set of small GICv4.1 tidy up patches
- Configuration cleanup for C-SKY interrupt chip
- Clarify the function documentation for irq_set_wake() to document that
the wakeup functionality is orthogonal to the irq disable/enable
mechanism.
-----BEGIN PGP SIGNATURE-----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=a9t/
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull interrupt fixes from Thomas Gleixner:
"A set of fixes for the interrupt subsystem:
- Provision only ACPI enabled redistributors on GICv3
- Use the proper command colums when building the INVALL command for
the GICv3-ITS
- Ensure the allocation of the L2 vPE table for GICv4.1
- Correct the GICv4.1 VPROBASER programming so it uses the proper
size
- A set of small GICv4.1 tidy up patches
- Configuration cleanup for C-SKY interrupt chip
- Clarify the function documentation for irq_set_wake() to document
that the wakeup functionality is orthogonal to the irq
disable/enable mechanism"
* tag 'irq-urgent-2020-02-09' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irqchip/gic-v3-its: Rename VPENDBASER/VPROPBASER accessors
irqchip/gic-v3-its: Remove superfluous WARN_ON
irqchip/gic-v4.1: Drop 'tmp' in inherit_vpe_l1_table_from_rd()
irqchip/gic-v4.1: Ensure L2 vPE table is allocated at RD level
irqchip/gic-v4.1: Set vpe_l1_base for all redistributors
irqchip/gic-v4.1: Fix programming of GICR_VPROPBASER_4_1_SIZE
genirq: Clarify that irq wake state is orthogonal to enable/disable
irqchip/gic-v3-its: Reference to its_invall_cmd descriptor when building INVALL
irqchip: Some Kconfig cleanup for C-SKY
irqchip/gic-v3: Only provision redistributors that are enabled in ACPI
Pull networking fixes from David Miller:
1) Unbalanced locking in mwifiex_process_country_ie, from Brian Norris.
2) Fix thermal zone registration in iwlwifi, from Andrei
Otcheretianski.
3) Fix double free_irq in sgi ioc3 eth, from Thomas Bogendoerfer.
4) Use after free in mptcp, from Florian Westphal.
5) Use after free in wireguard's root_remove_peer_lists, from Eric
Dumazet.
6) Properly access packets heads in bonding alb code, from Eric
Dumazet.
7) Fix data race in skb_queue_len(), from Qian Cai.
8) Fix regression in r8169 on some chips, from Heiner Kallweit.
9) Fix XDP program ref counting in hv_netvsc, from Haiyang Zhang.
10) Certain kinds of set link netlink operations can cause a NULL deref
in the ipv6 addrconf code. Fix from Eric Dumazet.
11) Don't cancel uninitialized work queue in drop monitor, from Ido
Schimmel.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
net: thunderx: use proper interface type for RGMII
mt76: mt7615: fix max_nss in mt7615_eeprom_parse_hw_cap
bpf: Improve bucket_log calculation logic
selftests/bpf: Test freeing sockmap/sockhash with a socket in it
bpf, sockhash: Synchronize_rcu before free'ing map
bpf, sockmap: Don't sleep while holding RCU lock on tear-down
bpftool: Don't crash on missing xlated program instructions
bpf, sockmap: Check update requirements after locking
drop_monitor: Do not cancel uninitialized work item
mlxsw: spectrum_dpipe: Add missing error path
mlxsw: core: Add validation of hardware device types for MGPIR register
mlxsw: spectrum_router: Clear offload indication from IPv6 nexthops on abort
selftests: mlxsw: Add test cases for local table route replacement
mlxsw: spectrum_router: Prevent incorrect replacement of local table routes
net: dsa: microchip: enable module autoprobe
ipv6/addrconf: fix potential NULL deref in inet6_set_link_af()
dpaa_eth: support all modes with rate adapting PHYs
net: stmmac: update pci platform data to use phy_interface
net: stmmac: xgmac: fix missing IFF_MULTICAST checki in dwxgmac2_set_filter
net: stmmac: fix missing IFF_MULTICAST check in dwmac4_set_filter
...
Pull vfs file system parameter updates from Al Viro:
"Saner fs_parser.c guts and data structures. The system-wide registry
of syntax types (string/enum/int32/oct32/.../etc.) is gone and so is
the horror switch() in fs_parse() that would have to grow another case
every time something got added to that system-wide registry.
New syntax types can be added by filesystems easily now, and their
namespace is that of functions - not of system-wide enum members. IOW,
they can be shared or kept private and if some turn out to be widely
useful, we can make them common library helpers, etc., without having
to do anything whatsoever to fs_parse() itself.
And we already get that kind of requests - the thing that finally
pushed me into doing that was "oh, and let's add one for timeouts -
things like 15s or 2h". If some filesystem really wants that, let them
do it. Without somebody having to play gatekeeper for the variants
blessed by direct support in fs_parse(), TYVM.
Quite a bit of boilerplate is gone. And IMO the data structures make a
lot more sense now. -200LoC, while we are at it"
* 'merge.nfs-fs_parse.1' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (25 commits)
tmpfs: switch to use of invalfc()
cgroup1: switch to use of errorfc() et.al.
procfs: switch to use of invalfc()
hugetlbfs: switch to use of invalfc()
cramfs: switch to use of errofc() et.al.
gfs2: switch to use of errorfc() et.al.
fuse: switch to use errorfc() et.al.
ceph: use errorfc() and friends instead of spelling the prefix out
prefix-handling analogues of errorf() and friends
turn fs_param_is_... into functions
fs_parse: handle optional arguments sanely
fs_parse: fold fs_parameter_desc/fs_parameter_spec
fs_parser: remove fs_parameter_description name field
add prefix to fs_context->log
ceph_parse_param(), ceph_parse_mon_ips(): switch to passing fc_log
new primitive: __fs_parse()
switch rbd and libceph to p_log-based primitives
struct p_log, variants of warnf() et.al. taking that one instead
teach logfc() to handle prefices, give it saner calling conventions
get rid of cg_invalf()
...
Daniel Borkmann says:
====================
pull-request: bpf 2020-02-07
The following pull-request contains BPF updates for your *net* tree.
We've added 15 non-merge commits during the last 10 day(s) which contain
a total of 12 files changed, 114 insertions(+), 31 deletions(-).
The main changes are:
1) Various BPF sockmap fixes related to RCU handling in the map's tear-
down code, from Jakub Sitnicki.
2) Fix macro state explosion in BPF sk_storage map when calculating its
bucket_log on allocation, from Martin KaFai Lau.
3) Fix potential BPF sockmap update race by rechecking socket's established
state under lock, from Lorenz Bauer.
4) Fix crash in bpftool on missing xlated instructions when kptr_restrict
sysctl is set, from Toke Høiland-Jørgensen.
5) Fix i40e's XSK wakeup code to return proper error in busy state and
various misc fixes in xdpsock BPF sample code, from Maciej Fijalkowski.
6) Fix the way modifiers are skipped in BTF in the verifier while walking
pointers to avoid program rejection, from Alexei Starovoitov.
7) Fix Makefile for runqslower BPF tool to i) rebuild on libbpf changes and
ii) to fix undefined reference linker errors for older gcc version due to
order of passed gcc parameters, from Yulia Kartseva and Song Liu.
8) Fix a trampoline_count BPF kselftest warning about missing braces around
initializer, from Andrii Nakryiko.
9) Fix up redundant "HAVE" prefix from large INSN limit kernel probe in
bpftool, from Michal Rostecki.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
There's some confusion around if an irq that's disabled with disable_irq()
can still wake the system from sleep states such as "suspend to RAM".
Clarify this in the kernel documentation for irq_set_irq_wake() so that
it's clear that an irq can be disabled and still wake the system if it has
been marked for wakeup.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lkml.kernel.org/r/20200206191521.94559-1-swboyd@chromium.org
Unused now.
Signed-off-by: Eric Sandeen <sandeen@redhat.com>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
In CONFIG_SMP=y kernels, smp_call_function_single() returns -ENXIO when
invoked for a non-existent CPU. In contrast, in CONFIG_SMP=n kernels,
a splat is emitted and smp_call_function_single() otherwise silently
ignores its "cpu" argument, instead pretending that the caller intended
to have something happen on CPU 0. Given that there is now code that
expects smp_call_function_single() to return an error if a bad CPU was
specified, this difference in semantics needs to be addressed.
Bring the semantics of the CONFIG_SMP=n version of
smp_call_function_single() into alignment with its CONFIG_SMP=y
counterpart.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200205143409.GA7021@paulmck-ThinkPad-P72
One of the simplifications added for 5.6-rc1 has caused build
regressions on some platforms (it was reported for sparc64).
This pull request fixes it with a direct revert.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
-----BEGIN PGP SIGNATURE-----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=Pb+W
-----END PGP SIGNATURE-----
Merge tag 'kgdb-fixes-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb fix from Daniel Thompson:
"One of the simplifications added for 5.6-rc1 has caused build
regressions on some platforms (it was reported for sparc64).
This fixes it with a revert"
* tag 'kgdb-fixes-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
Revert "kdb: Get rid of confusing diag msg from "rd" if current task has no regs"
This reverts commit bbfceba15f.
When DBG_MAX_REG_NUM is zero then a number of symbols are conditionally
defined. It is therefore not possible to check it using C expressions.
Reported-by: Anatoly Pugachev <matorola@gmail.com>
Acked-by: Doug Anderson <dianders@chromium.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
- Added new "bootconfig".
Looks for a file appended to initrd to add boot config options.
This has been discussed thoroughly at Linux Plumbers.
Very useful for adding kprobes at bootup.
Only enabled if "bootconfig" is on the real kernel command line.
- Created dynamic event creation.
Merges common code between creating synthetic events and
kprobe events.
- Rename perf "ring_buffer" structure to "perf_buffer"
- Rename ftrace "ring_buffer" structure to "trace_buffer"
Had to rename existing "trace_buffer" to "array_buffer"
- Allow trace_printk() to work withing (some) tracing code.
- Sort of tracing configs to be a little better organized
- Fixed bug where ftrace_graph hash was not being protected properly
- Various other small fixes and clean ups
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXjtAURQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qshOAQDzopQmvAVrrI6oogghr8JQA30Z2yqT
i+Ld7vPWL2MV9wEA1S+zLGDSYrj8f/vsCq6BxRYT1ApO+YtmY6LTXiUejwg=
=WNds
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- Added new "bootconfig".
This looks for a file appended to initrd to add boot config options,
and has been discussed thoroughly at Linux Plumbers.
Very useful for adding kprobes at bootup.
Only enabled if "bootconfig" is on the real kernel command line.
- Created dynamic event creation.
Merges common code between creating synthetic events and kprobe
events.
- Rename perf "ring_buffer" structure to "perf_buffer"
- Rename ftrace "ring_buffer" structure to "trace_buffer"
Had to rename existing "trace_buffer" to "array_buffer"
- Allow trace_printk() to work withing (some) tracing code.
- Sort of tracing configs to be a little better organized
- Fixed bug where ftrace_graph hash was not being protected properly
- Various other small fixes and clean ups
* tag 'trace-v5.6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (88 commits)
bootconfig: Show the number of nodes on boot message
tools/bootconfig: Show the number of bootconfig nodes
bootconfig: Add more parse error messages
bootconfig: Use bootconfig instead of boot config
ftrace: Protect ftrace_graph_hash with ftrace_sync
ftrace: Add comment to why rcu_dereference_sched() is open coded
tracing: Annotate ftrace_graph_notrace_hash pointer with __rcu
tracing: Annotate ftrace_graph_hash pointer with __rcu
bootconfig: Only load bootconfig if "bootconfig" is on the kernel cmdline
tracing: Use seq_buf for building dynevent_cmd string
tracing: Remove useless code in dynevent_arg_pair_add()
tracing: Remove check_arg() callbacks from dynevent args
tracing: Consolidate some synth_event_trace code
tracing: Fix now invalid var_ref_vals assumption in trace action
tracing: Change trace_boot to use synth_event interface
tracing: Move tracing selftests to bottom of menu
tracing: Move mmio tracer config up with the other tracers
tracing: Move tracing test module configs together
tracing: Move all function tracing configs together
tracing: Documentation for in-kernel synthetic event API
...
As function_graph tracer can run when RCU is not "watching", it can not be
protected by synchronize_rcu() it requires running a task on each CPU before
it can be freed. Calling schedule_on_each_cpu(ftrace_sync) needs to be used.
Link: https://lore.kernel.org/r/20200205131110.GT2935@paulmck-ThinkPad-P72
Cc: stable@vger.kernel.org
Fixes: b9b0c831be ("ftrace: Convert graph filter to use hash tables")
Reported-by: "Paul E. McKenney" <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Because the function graph tracer can execute in sections where RCU is not
"watching", the rcu_dereference_sched() for the has needs to be open coded.
This is fine because the RCU "flavor" of the ftrace hash is protected by
its own RCU handling (it does its own little synchronization on every CPU
and does not rely on RCU sched).
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix following instances of sparse error
kernel/trace/ftrace.c:5667:29: error: incompatible types in comparison
kernel/trace/ftrace.c:5813:21: error: incompatible types in comparison
kernel/trace/ftrace.c:5868:36: error: incompatible types in comparison
kernel/trace/ftrace.c:5870:25: error: incompatible types in comparison
Use rcu_dereference_protected to dereference the newly annotated pointer.
Link: http://lkml.kernel.org/r/20200205055701.30195-1-frextrite@gmail.com
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix following instances of sparse error
kernel/trace/ftrace.c:5664:29: error: incompatible types in comparison
kernel/trace/ftrace.c:5785:21: error: incompatible types in comparison
kernel/trace/ftrace.c:5864:36: error: incompatible types in comparison
kernel/trace/ftrace.c:5866:25: error: incompatible types in comparison
Use rcu_dereference_protected to access the __rcu annotated pointer.
Link: http://lkml.kernel.org/r/20200201072703.17330-1-frextrite@gmail.com
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Remove the unset dma_mask case as that won't get into mapping calls
anymore, and also report the other errors unconditonally and with a
slightly improved message. Remove the now pointless report_addr helper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad@darnok.org>
Untangle the way how dma_direct_map_page calls into swiotlb to be able
to properly report errors where the swiotlb DMA address overflows the
mask separately from overflows in the !swiotlb case. This means that
siotlb_map now has to do a little more work that duplicates
dma_direct_map_page, but doing so greatly simplifies the calling
convention.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
dma_direct_supported tries to find the minimum addressable bitmask
based on the end pfn and optional magic that architectures can use
to communicate the size of the magic ZONE_DMA that can be used
for bounce buffering. But between the DMA offsets that can change
per device (or sometimes even region), the fact the ZONE_DMA isn't
even guaranteed to be the lowest addresses and failure of having
proper interfaces to the MM code this fails at least for one
arm subarchitecture.
As all the legacy DMA implementations have supported 32-bit DMA
masks, and 32-bit masks are guranteed to always work by the API
contract (using bounce buffers if needed), we can short cut the
complicated check and always return true without breaking existing
assumptions. Hopefully we can properly clean up the interaction
with the arch defined zones and the bootmem allocator eventually.
Fixes: ad3c7b18c5 ("arm: use swiotlb for bounce buffering on LPAE configs")
Reported-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Pull vfs recursive removal updates from Al Viro:
"We have quite a few places where synthetic filesystems do an
equivalent of 'rm -rf', with varying amounts of code duplication,
wrong locking, etc. That really ought to be a library helper.
Only debugfs (and very similar tracefs) are converted here - I have
more conversions, but they'd never been in -next, so they'll have to
wait"
* 'work.recursive_removal' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
simple_recursive_removal(): kernel-side rm -rf for ramfs-style filesystems
kallsyms_token_table[] only contains ASCII characters. It should be
char instead of u8.
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Fix the way modifiers are skipped while walking pointers. Otherwise second
level dereferences of 'const struct foo *' will be rejected by the verifier.
Fixes: 9e15db6613 ("bpf: Implement accurate raw_tp context access via BTF")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200201000314.261392-1-ast@kernel.org
Everything for kgdb this time around is either simplifications or clean
ups.
In particular Douglas Anderson's modifications to the backtrace machine
in the *last* dev cycle have enabled Doug to tidy up some MIPS specific
backtrace code and stop sharing certain data structures across the
kernel. Note that The MIPS folks were on Cc: for the MIPS patch and
reacted positively (but without an explicit Acked-by).
Doug also got rid of the implicit switching between tasks and register
sets during some but not of kdb's backtrace actions (because the
implicit switching was either confusing for users, pointless or both).
Finally there is a coverity fix and patch to replace open coded console
traversal with the proper helper function.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
-----BEGIN PGP SIGNATURE-----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=igIA
-----END PGP SIGNATURE-----
Merge tag 'kgdb-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson:
"Everything for kgdb this time around is either simplifications or
clean ups.
In particular Douglas Anderson's modifications to the backtrace
machine in the *last* dev cycle have enabled Doug to tidy up some MIPS
specific backtrace code and stop sharing certain data structures
across the kernel. Note that The MIPS folks were on Cc: for the MIPS
patch and reacted positively (but without an explicit Acked-by).
Doug also got rid of the implicit switching between tasks and register
sets during some but not of kdb's backtrace actions (because the
implicit switching was either confusing for users, pointless or both).
Finally there is a coverity fix and patch to replace open coded
console traversal with the proper helper function"
* tag 'kgdb-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: Use for_each_console() helper
kdb: remove redundant assignment to pointer bp
kdb: Get rid of confusing diag msg from "rd" if current task has no regs
kdb: Gid rid of implicit setting of the current task / regs
kdb: kdb_current_task shouldn't be exported
kdb: kdb_current_regs should be private
MIPS: kdb: Remove old workaround for backtracing on other CPUs
The dynevent_cmd commands that build up the command string don't need
to do that themselves - there's a seq_buf facility that does pretty
much the same thing those command are doing manually, so use it
instead.
Link: http://lkml.kernel.org/r/eb8a6e835c964d0ab8a38cbf5ffa60746b54a465.1580506712.git.zanussi@kernel.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
It's kind of strange to have check_arg() callbacks as part of the arg
objects themselves; it makes more sense to just pass these in when the
args are added instead.
Remove the check_arg() callbacks from those objects which also means
removing the check_arg() args from the init functions, adding them to
the add functions and fixing up existing callers.
Link: http://lkml.kernel.org/r/c7708d6f177fcbe1a36b6e4e8e150907df0fa5d2.1580506712.git.zanussi@kernel.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Kernel crashes inside QEMU/KVM are observed:
kernel BUG at kernel/time/timer.c:1154!
BUG_ON(timer_pending(timer) || !timer->function) in add_timer_on().
At the same time another cpu got:
general protection fault: 0000 [#1] SMP PTI of poinson pointer 0xdead000000000200 in:
__hlist_del at include/linux/list.h:681
(inlined by) detach_timer at kernel/time/timer.c:818
(inlined by) expire_timers at kernel/time/timer.c:1355
(inlined by) __run_timers at kernel/time/timer.c:1686
(inlined by) run_timer_softirq at kernel/time/timer.c:1699
Unfortunately kernel logs are badly scrambled, stacktraces are lost.
Printing the timer->function before the BUG_ON() pointed to
clocksource_watchdog().
The execution of clocksource_watchdog() can race with a sequence of
clocksource_stop_watchdog() .. clocksource_start_watchdog():
expire_timers()
detach_timer(timer, true);
timer->entry.pprev = NULL;
raw_spin_unlock_irq(&base->lock);
call_timer_fn
clocksource_watchdog()
clocksource_watchdog_kthread() or
clocksource_unbind()
spin_lock_irqsave(&watchdog_lock, flags);
clocksource_stop_watchdog();
del_timer(&watchdog_timer);
watchdog_running = 0;
spin_unlock_irqrestore(&watchdog_lock, flags);
spin_lock_irqsave(&watchdog_lock, flags);
clocksource_start_watchdog();
add_timer_on(&watchdog_timer, ...);
watchdog_running = 1;
spin_unlock_irqrestore(&watchdog_lock, flags);
spin_lock(&watchdog_lock);
add_timer_on(&watchdog_timer, ...);
BUG_ON(timer_pending(timer) || !timer->function);
timer_pending() -> true
BUG()
I.e. inside clocksource_watchdog() watchdog_timer could be already armed.
Check timer_pending() before calling add_timer_on(). This is sufficient as
all operations are synchronized by watchdog_lock.
Fixes: 75c5158f70 ("timekeeping: Update clocksource with stop_machine")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/158048693917.4378.13823603769948933793.stgit@buzz
Evan tracked down a subtle race between the update of the MSI message and
the device raising an interrupt internally on PCI devices which do not
support MSI masking. The update of the MSI message is non-atomic and
consists of either 2 or 3 sequential 32bit wide writes to the PCI config
space.
- Write address low 32bits
- Write address high 32bits (If supported by device)
- Write data
When an interrupt is migrated then both address and data might change, so
the kernel attempts to mask the MSI interrupt first. But for MSI masking is
optional, so there exist devices which do not provide it. That means that
if the device raises an interrupt internally between the writes then a MSI
message is sent built from half updated state.
On x86 this can lead to spurious interrupts on the wrong interrupt
vector when the affinity setting changes both address and data. As a
consequence the device interrupt can be lost causing the device to
become stuck or malfunctioning.
Evan tried to handle that by disabling MSI accross an MSI message
update. That's not feasible because disabling MSI has issues on its own:
If MSI is disabled the PCI device is routing an interrupt to the legacy
INTx mechanism. The INTx delivery can be disabled, but the disablement is
not working on all devices.
Some devices lose interrupts when both MSI and INTx delivery are disabled.
Another way to solve this would be to enforce the allocation of the same
vector on all CPUs in the system for this kind of screwed devices. That
could be done, but it would bring back the vector space exhaustion problems
which got solved a few years ago.
Fortunately the high address (if supported by the device) is only relevant
when X2APIC is enabled which implies interrupt remapping. In the interrupt
remapping case the affinity setting is happening at the interrupt remapping
unit and the PCI MSI message is programmed only once when the PCI device is
initialized.
That makes it possible to solve it with a two step update:
1) Target the MSI msg to the new vector on the current target CPU
2) Target the MSI msg to the new vector on the new target CPU
In both cases writing the MSI message is only changing a single 32bit word
which prevents the issue of inconsistency.
After writing the final destination it is necessary to check whether the
device issued an interrupt while the intermediate state #1 (new vector,
current CPU) was in effect.
This is possible because the affinity change is always happening on the
current target CPU. The code runs with interrupts disabled, so the
interrupt can be detected by checking the IRR of the local APIC. If the
vector is pending in the IRR then the interrupt is retriggered on the new
target CPU by sending an IPI for the associated vector on the target CPU.
This can cause spurious interrupts on both the local and the new target
CPU.
1) If the new vector is not in use on the local CPU and the device
affected by the affinity change raised an interrupt during the
transitional state (step #1 above) then interrupt entry code will
ignore that spurious interrupt. The vector is marked so that the
'No irq handler for vector' warning is supressed once.
2) If the new vector is in use already on the local CPU then the IRR check
might see an pending interrupt from the device which is using this
vector. The IPI to the new target CPU will then invoke the handler of
the device, which got the affinity change, even if that device did not
issue an interrupt
3) If the new vector is in use already on the local CPU and the device
affected by the affinity change raised an interrupt during the
transitional state (step #1 above) then the handler of the device which
uses that vector on the local CPU will be invoked.
expose issues in device driver interrupt handlers which are not prepared to
handle a spurious interrupt correctly. This not a regression, it's just
exposing something which was already broken as spurious interrupts can
happen for a lot of reasons and all driver handlers need to be able to deal
with them.
Reported-by: Evan Green <evgreen@chromium.org>
Debugged-by: Evan Green <evgreen@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Evan Green <evgreen@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/87imkr4s7n.fsf@nanos.tec.linutronix.de
The synth_event trace code contains some almost identical functions
and some small functions that are called only once - consolidate the
common code into single functions and fold in the small functions to
simplify the code overall.
Link: http://lkml.kernel.org/r/d1c8d8ad124a653b7543afe801d38c199ca5c20e.1580506712.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull updates from Andrew Morton:
"Most of -mm and quite a number of other subsystems: hotfixes, scripts,
ocfs2, misc, lib, binfmt, init, reiserfs, exec, dma-mapping, kcov.
MM is fairly quiet this time. Holidays, I assume"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (118 commits)
kcov: ignore fault-inject and stacktrace
include/linux/io-mapping.h-mapping: use PHYS_PFN() macro in io_mapping_map_atomic_wc()
execve: warn if process starts with executable stack
reiserfs: prevent NULL pointer dereference in reiserfs_insert_item()
init/main.c: fix misleading "This architecture does not have kernel memory protection" message
init/main.c: fix quoted value handling in unknown_bootoption
init/main.c: remove unnecessary repair_env_string in do_initcall_level
init/main.c: log arguments and environment passed to init
fs/binfmt_elf.c: coredump: allow process with empty address space to coredump
fs/binfmt_elf.c: coredump: delete duplicated overflow check
fs/binfmt_elf.c: coredump: allocate core ELF header on stack
fs/binfmt_elf.c: make BAD_ADDR() unlikely
fs/binfmt_elf.c: better codegen around current->mm
fs/binfmt_elf.c: don't copy ELF header around
fs/binfmt_elf.c: fix ->start_code calculation
fs/binfmt_elf.c: smaller code generation around auxv vector fill
lib/find_bit.c: uninline helper _find_next_bit()
lib/find_bit.c: join _find_next_bit{_le}
uapi: rename ext2_swab() to swab() and share globally in swab.h
lib/scatterlist.c: adjust indentation in __sg_alloc_table
...
Summary of modules changes for the 5.6 merge window:
- Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings to
indicate to the linker that it can perform string deduplication (i.e.,
duplicate strings are reduced to a single copy in the string table).
This means any repeated namespace string would be merged to just one
entry in __ksymtab_strings.
- Various code cleanups and small fixes (fix small memleak in error path,
improve moduleparam docs, silence rcu warnings, improve error logging)
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-----BEGIN PGP SIGNATURE-----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=boqg
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 5.6 merge window:
- Add "MS" (SHF_MERGE|SHF_STRINGS) section flags to __ksymtab_strings
to indicate to the linker that it can perform string deduplication
(i.e., duplicate strings are reduced to a single copy in the string
table). This means any repeated namespace string would be merged to
just one entry in __ksymtab_strings.
- Various code cleanups and small fixes (fix small memleak in error
path, improve moduleparam docs, silence rcu warnings, improve error
logging)"
* tag 'modules-for-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module.h: Annotate mod_kallsyms with __rcu
module: avoid setting info->name early in case we can fall back to info->mod->name
modsign: print module name along with error message
kernel/module: Fix memleak in module_add_modinfo_attrs()
export.h: reduce __ksymtab_strings string duplication by using "MS" section flags
moduleparam: fix kerneldoc
modules: lockdep: Suppress suspicious RCU usage warning
Don't instrument 3 more files that contain debugging facilities and
produce large amounts of uninteresting coverage for every syscall.
The following snippets are sprinkled all over the place in kcov traces
in a debugging kernel. We already try to disable instrumentation of
stack unwinding code and of most debug facilities. I guess we did not
use fault-inject.c at the time, and stacktrace.c was somehow missed (or
something has changed in kernel/configs). This change both speeds up
kcov (kernel doesn't need to store these PCs, user-space doesn't need to
process them) and frees trace buffer capacity for more useful coverage.
should_fail
lib/fault-inject.c:149
fail_dump
lib/fault-inject.c:45
stack_trace_save
kernel/stacktrace.c:124
stack_trace_consume_entry
kernel/stacktrace.c:86
stack_trace_consume_entry
kernel/stacktrace.c:89
... a hundred frames skipped ...
stack_trace_consume_entry
kernel/stacktrace.c:93
stack_trace_consume_entry
kernel/stacktrace.c:86
Link: http://lkml.kernel.org/r/20200116111449.217744-1-dvyukov@gmail.com
Signed-off-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The patch 'tracing: Fix histogram code when expression has same var as
value' added code to return an existing variable reference when
creating a new variable reference, which resulted in var_ref_vals
slots being reused instead of being duplicated.
The implementation of the trace action assumes that the end of the
var_ref_vals array starting at action_data.var_ref_idx corresponds to
the values that will be assigned to the trace params. The patch
mentioned above invalidates that assumption, which means that each
param needs to explicitly specify its index into var_ref_vals.
This fix changes action_data.var_ref_idx to an array of var ref
indexes to account for that.
Link: https://lore.kernel.org/r/1580335695.6220.8.camel@kernel.org
Fixes: 8bcebc77e8 ("tracing: Fix histogram code when expression has same var as value")
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Have trace_boot_add_synth_event() use the synth_event interface.
Also, rename synth_event_run_cmd() to synth_event_run_command() now
that trace_boot's version is gone.
Link: http://lkml.kernel.org/r/94f1fa0e31846d0bddca916b8663404b20559e34.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Replace open coded single-linked list iteration loop with for_each_console()
helper in use.
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
The point bp is assigned a value that is never read, it is being
re-assigned later to bp = &kdb_breakpoints[lowbp] in a for-loop.
Remove the redundant assignment.
Addresses-Coverity ("Unused value")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Link: https://lore.kernel.org/r/20191128130753.181246-1-colin.king@canonical.com
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
If you switch to a sleeping task with the "pid" command and then type
"rd", kdb tells you this:
No current kdb registers. You may need to select another task
diag: -17: Invalid register name
The first message makes sense, but not the second. Fix it by just
returning 0 after commands accessing the current registers finish if
we've already printed the "No current kdb registers" error.
While fixing kdb_rd(), change the function to use "if" rather than
"ifdef". It cleans the function up a bit and any modern compiler will
have no trouble handling still producing good code.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191109111624.5.I121f4c6f0c19266200bf6ef003de78841e5bfc3d@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Some (but not all?) of the kdb backtrace paths would cause the
kdb_current_task and kdb_current_regs to remain changed. As discussed
in a review of a previous patch [1], this doesn't seem intuitive, so
let's fix that.
...but, it turns out that there's actually no longer any reason to set
the current task / current regs while backtracing anymore anyway. As
of commit 2277b49258 ("kdb: Fix stack crawling on 'running' CPUs
that aren't the master") if we're backtracing on a task running on a
CPU we ask that CPU to do the backtrace itself. Linux can do that
without anything fancy. If we're doing backtrace on a sleeping task
we can also do that fine without updating globals. So this patch
mostly just turns into deleting a bunch of code.
[1] https://lore.kernel.org/r/20191010150735.dhrj3pbjgmjrdpwr@holly.lan
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191109111624.4.Ibc3d982bbeb9e46872d43973ba808cd4c79537c7@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
The kdb_current_task variable has been declared in
"kernel/debug/kdb/kdb_private.h" since 2010 when kdb was added to the
mainline kernel. This is not a public header. There should be no
reason that kdb_current_task should be exported and there are no
in-kernel users that need it. Remove the export.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191109111623.3.I14b22b5eb15ca8f3812ab33e96621231304dc1f7@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
As of the patch ("MIPS: kdb: Remove old workaround for backtracing on
other CPUs") there is no reason for kdb_current_regs to be in the
public "kdb.h". Let's move it next to kdb_current_task.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191109111623.2.Iadbfb484e90b557cc4b5ac9890bfca732cd99d77@changeid
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
5153faac18 ("cgroup: remove cgroup_enable_task_cg_lists()
optimization") removed lazy initialization of css_sets so that new
tasks are always lniked to its css_set. In the process, it incorrectly
ended up adding init_tasks to root css_set. They show up as PID 0's in
root's cgroup.procs triggering warnings in systemd and generally
confusing people.
Fix it by skip css_set linking for init_tasks.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: https://github.com/joanbm
Link: https://github.com/systemd/systemd/issues/14682
Fixes: 5153faac18 ("cgroup: remove cgroup_enable_task_cg_lists() optimization")
Cc: stable@vger.kernel.org # v5.5+
Move all the tracing selftest configs to the bottom of the tracing menu.
There's no reason for them to be interspersed throughout.
Also, move the bootconfig menu to the top.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Move the config that enables the mmiotracer with the other tracers such that
all the tracers are together.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The MMIO test module was by itself, move it to the other test modules. Also,
add the text "Test module" to PREEMPTIRQ_DELAY_TEST as that create a test
module as well.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The features that depend on the function tracer were spread out through the
tracing menu, pull them together as it is easier to manage.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a test module that checks the basic functionality of the in-kernel
kprobe event command generation API by creating kprobe events from a
module.
Link: http://lkml.kernel.org/r/97e502b204f9dba948e3fa3a4315448298218787.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Have trace_boot_add_kprobe_event() use the kprobe_event interface.
Also, rename kprobe_event_run_cmd() to kprobe_event_run_command() now
that trace_boot's version is gone.
Link: http://lkml.kernel.org/r/af5429d11291ab1e9a85a0ff944af3b2bcf193c7.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add functions used to generate kprobe event commands, built on top of
the dynevent_cmd interface.
kprobe_event_gen_cmd_start() is used to create a kprobe event command
using a variable arg list, and kretprobe_event_gen_cmd_start() does
the same for kretprobe event commands. kprobe_event_add_fields() can
be used to add single fields one by one or as a group. Once all
desired fields are added, kprobe_event_gen_cmd_end() or
kretprobe_event_gen_cmd_end() respectively are used to actually
execute the command and create the event.
Link: http://lkml.kernel.org/r/95cc4696502bb6017f9126f306a45ad19b4cc14f.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a test module that checks the basic functionality of the in-kernel
synthetic event generation API by generating and tracing synthetic
events from a module.
Link: http://lkml.kernel.org/r/fcb4dd9eb9eefb70ab20538d3529d51642389664.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add an exported function named synth_event_trace(), allowing modules
or other kernel code to trace synthetic events.
Also added are several functions that allow the same functionality to
be broken out in a piecewise fashion, which are useful in situations
where tracing an event from a full array of values would be
cumbersome. Those functions are synth_event_trace_start/end() and
synth_event_add_(next)_val().
Link: http://lkml.kernel.org/r/7a84de5f1854acf4144b57efe835ca645afa764f.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add functions used to generate synthetic event commands, built on top
of the dynevent_cmd interface.
synth_event_gen_cmd_start() is used to create a synthetic event
command using a variable arg list and
synth_event_gen_cmd_array_start() does the same thing but using an
array of field descriptors. synth_event_add_field(),
synth_event_add_field_str() and synth_event_add_fields() can be used
to add single fields one by one or as a group. Once all desired
fields are added, synth_event_gen_cmd_end() is used to actually
execute the command and create the event.
synth_event_create() does everything, including creating the event, in
a single call.
Link: http://lkml.kernel.org/r/38fef702fad5ef208009f459552f34a94befd860.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add an interface used to build up dynamic event creation commands,
such as synthetic and kprobe events. Interfaces specific to those
particular types of events and others can be built on top of this
interface.
Command creation is started by first using the dynevent_cmd_init()
function to initialize the dynevent_cmd object. Following that, args
are appended and optionally checked by the dynevent_arg_add() and
dynevent_arg_pair_add() functions, which use objects representing
arguments and pairs of arguments, initialized respectively by
dynevent_arg_init() and dynevent_arg_pair_init(). Finally, once all
args have been successfully added, the command is finalized and
actually created using dynevent_create().
The code here for actually printing into the dyn_event->cmd buffer
using snprintf() etc was adapted from v4 of Masami's 'tracing/boot:
Add synthetic event support' patch.
Link: http://lkml.kernel.org/r/1f65fa44390b6f238f6036777c3784ced1dcc6a0.1580323897.git.zanussi@kernel.org
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
create_or_delete_synth_event() contains code to delete a synthetic
event, which would be useful on its own - specifically, it would be
useful to allow event-creating modules to call it separately.
Separate out the delete code from that function and create an exported
function named synth_event_delete().
Link: http://lkml.kernel.org/r/050db3b06df7f0a4b8a2922da602d1d879c7c1c2.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a function to get an event file and prevent it from going away on
module or instance removal.
trace_get_event_file() will find an event file in a given instance (if
instance is NULL, it assumes the top trace array) and return it,
pinning the instance's trace array as well as the event's module, if
applicable, so they won't go away while in use.
trace_put_event_file() does the matching release.
Link: http://lkml.kernel.org/r/bb31ac4bdda168d5ed3c4b5f5a4c8f633e8d9118.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
[ Moved trace_array_put() to end of trace_put_event_file() ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add a new trace_array_find() function that can be used to find a trace
array given the instance name, and replace existing code that does the
same thing with it. Also add trace_array_find_get() which does the
same but returns the trace array after upping its refcount.
Also make both available for use outside of trace.c.
Link: http://lkml.kernel.org/r/cb68528c975eba95bee4561ac67dd1499423b2e5.1580323897.git.zanussi@kernel.org
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.
Without patch:
# dd bs=30 skip=1 if=/sys/kernel/tracing/events/sched/sched_switch/trigger
dd: /sys/kernel/tracing/events/sched/sched_switch/trigger: cannot skip to specified offset
n traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist
# Available triggers:
# traceon traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist
6+1 records in
6+1 records out
206 bytes copied, 0.00027916 s, 738 kB/s
Notice the printing of "# Available triggers:..." after the line.
With the patch:
# dd bs=30 skip=1 if=/sys/kernel/tracing/events/sched/sched_switch/trigger
dd: /sys/kernel/tracing/events/sched/sched_switch/trigger: cannot skip to specified offset
n traceoff snapshot stacktrace enable_event disable_event enable_hist disable_hist hist
2+1 records in
2+1 records out
88 bytes copied, 0.000526867 s, 167 kB/s
It only prints the end of the file, and does not restart.
Link: http://lkml.kernel.org/r/3c35ee24-dd3a-8119-9c19-552ed253388a@virtuozzo.comhttps://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.
Link: http://lkml.kernel.org/r/7ad85b22-1866-977c-db17-88ac438bc764@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
[ This is not a bug fix, it just makes it "technically correct"
which is why I applied it. NULL is only returned on an anomaly
which triggers a WARN_ON ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
if seq_file .next fuction does not change position index,
read after some lseek can generate unexpected output.
Without patch:
# dd bs=4 skip=1 if=/sys/kernel/tracing/set_ftrace_pid
dd: /sys/kernel/tracing/set_ftrace_pid: cannot skip to specified offset
id
no pid
2+1 records in
2+1 records out
10 bytes copied, 0.000213285 s, 46.9 kB/s
Notice the "id" followed by "no pid".
With the patch:
# dd bs=4 skip=1 if=/sys/kernel/tracing/set_ftrace_pid
dd: /sys/kernel/tracing/set_ftrace_pid: cannot skip to specified offset
id
0+1 records in
0+1 records out
3 bytes copied, 0.000202112 s, 14.8 kB/s
Notice that it only prints "id" and not the "no pid" afterward.
Link: http://lkml.kernel.org/r/4f87c6ad-f114-30bb-8506-c32274ce2992@virtuozzo.comhttps://bugzilla.kernel.org/show_bug.cgi?id=206283
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reading the sched_cmdline_ref and sched_tgid_ref initial state within
tracing_start_sched_switch without holding the sched_register_mutex is
racy against concurrent updates, which can lead to tracepoint probes
being registered more than once (and thus trigger warnings within
tracepoint.c).
[ May be the fix for this bug ]
Link: https://lore.kernel.org/r/000000000000ab6f84056c786b93@google.com
Link: http://lkml.kernel.org/r/20190817141208.15226-1-mathieu.desnoyers@efficios.com
Cc: stable@vger.kernel.org
CC: Steven Rostedt (VMware) <rostedt@goodmis.org>
CC: Joel Fernandes (Google) <joel@joelfernandes.org>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Paul E. McKenney <paulmck@linux.ibm.com>
Reported-by: syzbot+774fddf07b7ab29a1e55@syzkaller.appspotmail.com
Fixes: d914ba37d7 ("tracing: Add support for recording tgid of tasks")
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Although the device tree might contain a reserved-memory DT node
dedicated as the default CMA pool, users might want to change CMA's
parameters using the kernel command line for debugging purposes and
whatnot. Honor this by bypassing the reserved memory CMA setup, which
will ultimately end up freeing the memblock and allow the command line
CMA configuration routine to run.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Phil Elwell <phil@raspberrypi.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This small series revises the names in mmu_notifier to make the code
clearer and more readable.
-----BEGIN PGP SIGNATURE-----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=hhT0
-----END PGP SIGNATURE-----
Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull mmu_notifier updates from Jason Gunthorpe:
"This small series revises the names in mmu_notifier to make the code
clearer and more readable"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
mm/mmu_notifiers: Use 'interval_sub' as the variable for mmu_interval_notifier
mm/mmu_notifiers: Use 'subscription' as the variable name for mmu_notifier
mm/mmu_notifier: Rename struct mmu_notifier_mm to mmu_notifier_subscriptions
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXjFo8wAKCRCRxhvAZXjc
omaGAQDVwCHQekqxp2eC8EJH4Pkt+Bn1BLrA25stlTo93YBPHgEAsPVUCRNcrZAl
VncYmxCfpt3Yu0S/MTVXu5xrRiIXPQk=
=uqTN
-----END PGP SIGNATURE-----
Merge tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread management updates from Christian Brauner:
"Sargun Dhillon over the last cycle has worked on the pidfd_getfd()
syscall.
This syscall allows for the retrieval of file descriptors of a process
based on its pidfd. A task needs to have ptrace_may_access()
permissions with PTRACE_MODE_ATTACH_REALCREDS (suggested by Oleg and
Andy) on the target.
One of the main use-cases is in combination with seccomp's user
notification feature. As a reminder, seccomp's user notification
feature was made available in v5.0. It allows a task to retrieve a
file descriptor for its seccomp filter. The file descriptor is usually
handed of to a more privileged supervising process. The supervisor can
then listen for syscall events caught by the seccomp filter of the
supervisee and perform actions in lieu of the supervisee, usually
emulating syscalls. pidfd_getfd() is needed to expand its uses.
There are currently two major users that wait on pidfd_getfd() and one
future user:
- Netflix, Sargun said, is working on a service mesh where users
should be able to connect to a dns-based VIP. When a user connects
to e.g. 1.2.3.4:80 that runs e.g. service "foo" they will be
redirected to an envoy process. This service mesh uses seccomp user
notifications and pidfd to intercept all connect calls and instead
of connecting them to 1.2.3.4:80 connects them to e.g.
127.0.0.1:8080.
- LXD uses the seccomp notifier heavily to intercept and emulate
mknod() and mount() syscalls for unprivileged containers/processes.
With pidfd_getfd() more uses-cases e.g. bridging socket connections
will be possible.
- The patchset has also seen some interest from the browser corner.
Right now, Firefox is using a SECCOMP_RET_TRAP sandbox managed by a
broker process. In the future glibc will start blocking all signals
during dlopen() rendering this type of sandbox impossible. Hence,
in the future Firefox will switch to a seccomp-user-nofication
based sandbox which also makes use of file descriptor retrieval.
The thread for this can be found at
https://sourceware.org/ml/libc-alpha/2019-12/msg00079.html
With pidfd_getfd() it is e.g. possible to bridge socket connections
for the supervisee (binding to a privileged port) and taking actions
on file descriptors on behalf of the supervisee in general.
Sargun's first version was using an ioctl on pidfds but various people
pushed for it to be a proper syscall which he duely implemented as
well over various review cycles. Selftests are of course included.
I've also added instructions how to deal with merge conflicts below.
There's also a small fix coming from the kernel mentee project to
correctly annotate struct sighand_struct with __rcu to fix various
sparse warnings. We've received a few more such fixes and even though
they are mostly trivial I've decided to postpone them until after -rc1
since they came in rather late and I don't want to risk introducing
build warnings.
Finally, there's a new prctl() command PR_{G,S}ET_IO_FLUSHER which is
needed to avoid allocation recursions triggerable by storage drivers
that have userspace parts that run in the IO path (e.g. dm-multipath,
iscsi, etc). These allocation recursions deadlock the device.
The new prctl() allows such privileged userspace components to avoid
allocation recursions by setting the PF_MEMALLOC_NOIO and
PF_LESS_THROTTLE flags. The patch carries the necessary acks from the
relevant maintainers and is routed here as part of prctl()
thread-management."
* tag 'threads-v5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
prctl: PR_{G,S}ET_IO_FLUSHER to support controlling memory reclaim
sched.h: Annotate sighand_struct with __rcu
test: Add test for pidfd getfd
arch: wire up pidfd_getfd syscall
pid: Implement pidfd_getfd syscall
vfs, fdtable: Add fget_task helper
This kunit update for Linux 5.6-rc1 consists of:
-- Support for building kunit as a module from Alan Maguire
-- AppArmor KUnit tests for policy unpack from Mike Salvatore
-----BEGIN PGP SIGNATURE-----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=AFO4
-----END PGP SIGNATURE-----
Merge tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull Kselftest kunit updates from Shuah Khan:
"This kunit update consists of:
- Support for building kunit as a module from Alan Maguire
- AppArmor KUnit tests for policy unpack from Mike Salvatore"
* tag 'linux-kselftest-5.6-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
kunit: building kunit as a module breaks allmodconfig
kunit: update documentation to describe module-based build
kunit: allow kunit to be loaded as a module
kunit: remove timeout dependence on sysctl_hung_task_timeout_seconds
kunit: allow kunit tests to be loaded as a module
kunit: hide unexported try-catch interface in try-catch-impl.h
kunit: move string-stream.h to lib/kunit
apparmor: add AppArmor KUnit tests for policy unpack
These are updates to device drivers and file systems that for some reason
or another were not included in the kernel in the previous y2038 series.
I've gone through all users of time_t again to make sure the kernel is
in a long-term maintainable state, replacing all remaining references
to time_t with safe alternatives.
Some related parts of the series were picked up into the nfsd, xfs,
alsa and v4l2 trees. A final set of patches in linux-mm removes the now
unused time_t/timeval/timespec types and helper functions after all five
branches are merged for linux-5.6, ensuring that no new users get merged.
As a result, linux-5.6, or my backport of the patches to 5.4 [1], should
be the first release that can serve as a base for a 32-bit system designed
to run beyond year 2038, with a few remaining caveats:
- All user space must be compiled with a 64-bit time_t, which will be
supported in the coming musl-1.2 and glibc-2.32 releases, along with
installed kernel headers from linux-5.6 or higher.
- Applications that use the system call interfaces directly need to be
ported to use the time64 syscalls added in linux-5.1 in place of the
existing system calls. This impacts most users of futex() and seccomp()
as well as programming languages that have their own runtime environment
not based on libc.
- Applications that use a private copy of kernel uapi header files or
their contents may need to update to the linux-5.6 version, in
particular for sound/asound.h, xfs/xfs_fs.h, linux/input.h,
linux/elfcore.h, linux/sockios.h, linux/timex.h and linux/can/bcm.h.
- A few remaining interfaces cannot be changed to pass a 64-bit time_t
in a compatible way, so they must be configured to use CLOCK_MONOTONIC
times or (with a y2106 problem) unsigned 32-bit timestamps. Most
importantly this impacts all users of 'struct input_event'.
- All y2038 problems that are present on 64-bit machines also apply to
32-bit machines. In particular this affects file systems with on-disk
timestamps using signed 32-bit seconds: ext4 with ext3-style small
inodes, ext2, xfs (to be fixed soon) and ufs.
Changes since v1 [2]:
- Add Acks I received
- Rebase to v5.5-rc1, dropping patches that got merged already
- Add NFS, XFS and the final three patches from another series
- Rewrite etnaviv patches
- Add one late revert to avoid an etnaviv regression
[1] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=y2038-endgame
[2] https://lore.kernel.org/lkml/20191108213257.3097633-1-arnd@arndb.de/
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=wx0A
-----END PGP SIGNATURE-----
Merge tag 'y2038-drivers-for-v5.6-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground
Pull y2038 updates from Arnd Bergmann:
"Core, driver and file system changes
These are updates to device drivers and file systems that for some
reason or another were not included in the kernel in the previous
y2038 series.
I've gone through all users of time_t again to make sure the kernel is
in a long-term maintainable state, replacing all remaining references
to time_t with safe alternatives.
Some related parts of the series were picked up into the nfsd, xfs,
alsa and v4l2 trees. A final set of patches in linux-mm removes the
now unused time_t/timeval/timespec types and helper functions after
all five branches are merged for linux-5.6, ensuring that no new users
get merged.
As a result, linux-5.6, or my backport of the patches to 5.4 [1],
should be the first release that can serve as a base for a 32-bit
system designed to run beyond year 2038, with a few remaining caveats:
- All user space must be compiled with a 64-bit time_t, which will be
supported in the coming musl-1.2 and glibc-2.32 releases, along
with installed kernel headers from linux-5.6 or higher.
- Applications that use the system call interfaces directly need to
be ported to use the time64 syscalls added in linux-5.1 in place of
the existing system calls. This impacts most users of futex() and
seccomp() as well as programming languages that have their own
runtime environment not based on libc.
- Applications that use a private copy of kernel uapi header files or
their contents may need to update to the linux-5.6 version, in
particular for sound/asound.h, xfs/xfs_fs.h, linux/input.h,
linux/elfcore.h, linux/sockios.h, linux/timex.h and
linux/can/bcm.h.
- A few remaining interfaces cannot be changed to pass a 64-bit
time_t in a compatible way, so they must be configured to use
CLOCK_MONOTONIC times or (with a y2106 problem) unsigned 32-bit
timestamps. Most importantly this impacts all users of 'struct
input_event'.
- All y2038 problems that are present on 64-bit machines also apply
to 32-bit machines. In particular this affects file systems with
on-disk timestamps using signed 32-bit seconds: ext4 with
ext3-style small inodes, ext2, xfs (to be fixed soon) and ufs"
[1] https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/log/?h=y2038-endgame
* tag 'y2038-drivers-for-v5.6-signed' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (21 commits)
Revert "drm/etnaviv: reject timeouts with tv_nsec >= NSEC_PER_SEC"
y2038: sh: remove timeval/timespec usage from headers
y2038: sparc: remove use of struct timex
y2038: rename itimerval to __kernel_old_itimerval
y2038: remove obsolete jiffies conversion functions
nfs: fscache: use timespec64 in inode auxdata
nfs: fix timstamp debug prints
nfs: use time64_t internally
sunrpc: convert to time64_t for expiry
drm/etnaviv: avoid deprecated timespec
drm/etnaviv: reject timeouts with tv_nsec >= NSEC_PER_SEC
drm/msm: avoid using 'timespec'
hfs/hfsplus: use 64-bit inode timestamps
hostfs: pass 64-bit timestamps to/from user space
packet: clarify timestamp overflow
tsacct: add 64-bit btime field
acct: stop using get_seconds()
um: ubd: use 64-bit time_t where possible
xtensa: ISS: avoid struct timeval
dlm: use SO_SNDTIMEO_NEW instead of SO_SNDTIMEO_OLD
...
Pull openat2 support from Al Viro:
"This is the openat2() series from Aleksa Sarai.
I'm afraid that the rest of namei stuff will have to wait - it got
zero review the last time I'd posted #work.namei, and there had been a
leak in the posted series I'd caught only last weekend. I was going to
repost it on Monday, but the window opened and the odds of getting any
review during that... Oh, well.
Anyway, openat2 part should be ready; that _did_ get sane amount of
review and public testing, so here it comes"
From Aleksa's description of the series:
"For a very long time, extending openat(2) with new features has been
incredibly frustrating. This stems from the fact that openat(2) is
possibly the most famous counter-example to the mantra "don't silently
accept garbage from userspace" -- it doesn't check whether unknown
flags are present[1].
This means that (generally) the addition of new flags to openat(2) has
been fraught with backwards-compatibility issues (O_TMPFILE has to be
defined as __O_TMPFILE|O_DIRECTORY|[O_RDWR or O_WRONLY] to ensure old
kernels gave errors, since it's insecure to silently ignore the
flag[2]). All new security-related flags therefore have a tough road
to being added to openat(2).
Furthermore, the need for some sort of control over VFS's path
resolution (to avoid malicious paths resulting in inadvertent
breakouts) has been a very long-standing desire of many userspace
applications.
This patchset is a revival of Al Viro's old AT_NO_JUMPS[3] patchset
(which was a variant of David Drysdale's O_BENEATH patchset[4] which
was a spin-off of the Capsicum project[5]) with a few additions and
changes made based on the previous discussion within [6] as well as
others I felt were useful.
In line with the conclusions of the original discussion of
AT_NO_JUMPS, the flag has been split up into separate flags. However,
instead of being an openat(2) flag it is provided through a new
syscall openat2(2) which provides several other improvements to the
openat(2) interface (see the patch description for more details). The
following new LOOKUP_* flags are added:
LOOKUP_NO_XDEV:
Blocks all mountpoint crossings (upwards, downwards, or through
absolute links). Absolute pathnames alone in openat(2) do not
trigger this. Magic-link traversal which implies a vfsmount jump is
also blocked (though magic-link jumps on the same vfsmount are
permitted).
LOOKUP_NO_MAGICLINKS:
Blocks resolution through /proc/$pid/fd-style links. This is done
by blocking the usage of nd_jump_link() during resolution in a
filesystem. The term "magic-links" is used to match with the only
reference to these links in Documentation/, but I'm happy to change
the name.
It should be noted that this is different to the scope of
~LOOKUP_FOLLOW in that it applies to all path components. However,
you can do openat2(NO_FOLLOW|NO_MAGICLINKS) on a magic-link and it
will *not* fail (assuming that no parent component was a
magic-link), and you will have an fd for the magic-link.
In order to correctly detect magic-links, the introduction of a new
LOOKUP_MAGICLINK_JUMPED state flag was required.
LOOKUP_BENEATH:
Disallows escapes to outside the starting dirfd's
tree, using techniques such as ".." or absolute links. Absolute
paths in openat(2) are also disallowed.
Conceptually this flag is to ensure you "stay below" a certain
point in the filesystem tree -- but this requires some additional
to protect against various races that would allow escape using
"..".
Currently LOOKUP_BENEATH implies LOOKUP_NO_MAGICLINKS, because it
can trivially beam you around the filesystem (breaking the
protection). In future, there might be similar safety checks done
as in LOOKUP_IN_ROOT, but that requires more discussion.
In addition, two new flags are added that expand on the above ideas:
LOOKUP_NO_SYMLINKS:
Does what it says on the tin. No symlink resolution is allowed at
all, including magic-links. Just as with LOOKUP_NO_MAGICLINKS this
can still be used with NOFOLLOW to open an fd for the symlink as
long as no parent path had a symlink component.
LOOKUP_IN_ROOT:
This is an extension of LOOKUP_BENEATH that, rather than blocking
attempts to move past the root, forces all such movements to be
scoped to the starting point. This provides chroot(2)-like
protection but without the cost of a chroot(2) for each filesystem
operation, as well as being safe against race attacks that
chroot(2) is not.
If a race is detected (as with LOOKUP_BENEATH) then an error is
generated, and similar to LOOKUP_BENEATH it is not permitted to
cross magic-links with LOOKUP_IN_ROOT.
The primary need for this is from container runtimes, which
currently need to do symlink scoping in userspace[7] when opening
paths in a potentially malicious container.
There is a long list of CVEs that could have bene mitigated by
having RESOLVE_THIS_ROOT (such as CVE-2017-1002101,
CVE-2017-1002102, CVE-2018-15664, and CVE-2019-5736, just to name a
few).
In order to make all of the above more usable, I'm working on
libpathrs[8] which is a C-friendly library for safe path resolution.
It features a userspace-emulated backend if the kernel doesn't support
openat2(2). Hopefully we can get userspace to switch to using it, and
thus get openat2(2) support for free once it's ready.
Future work would include implementing things like
RESOLVE_NO_AUTOMOUNT and possibly a RESOLVE_NO_REMOTE (to allow
programs to be sure they don't hit DoSes though stale NFS handles)"
* 'work.openat2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
Documentation: path-lookup: include new LOOKUP flags
selftests: add openat2(2) selftests
open: introduce openat2(2) syscall
namei: LOOKUP_{IN_ROOT,BENEATH}: permit limited ".." resolution
namei: LOOKUP_IN_ROOT: chroot-like scoped resolution
namei: LOOKUP_BENEATH: O_BENEATH-like scoped resolution
namei: LOOKUP_NO_XDEV: block mountpoint crossing
namei: LOOKUP_NO_MAGICLINKS: block magic-link resolution
namei: LOOKUP_NO_SYMLINKS: block symlink resolution
namei: allow set_root() to produce errors
namei: allow nd_jump_link() to produce errors
nsfs: clean-up ns_get_path() signature to return int
namei: only return -ECHILD from follow_dotdot_rcu()
Pull RCU warning removal from Paul McKenney:
"A single commit that fixes an embarrassing bug discussed here:
https://lore.kernel.org/lkml/20200125131425.GB16136@zn.tnic/
which apparently also affects smaller systems"
[ This was sent to Ingo, but since I see the issue on the laptop I use for
testing during the merge window, I'm doing the pull directly - Linus ]
* 'urgent-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu:
rcu: Forgive slow expedited grace periods at boot time
Instead of using a locally defined "struct bpf_verifier_log log = {}",
btf_struct_ops_init() should reuse the "log" from its calling
function "btf_parse_vmlinux()". It should also resolve the
frame-size too large compiler warning in some ARCH.
Fixes: 27ae7997a6 ("bpf: Introduce BPF_PROG_TYPE_STRUCT_OPS")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200127175145.1154438-1-kafai@fb.com
Move external function declarations into kernel/trace/trace.h
from trace_boot.c for tracing subsystem internal use.
Link: http://lkml.kernel.org/r/158029060405.12381.11944554430359702545.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The 'hist:' prefix gets stripped from the command text during command
processing, but should be added back when displaying the command
during error processing.
Not only because it's what should be displayed but also because not
having it means the test cases fail because the caret is miscalculated
by the length of the prefix string.
Link: http://lkml.kernel.org/r/449df721f560042e22382f67574bcc5b4d830d3d.1561743018.git.zanussi@kernel.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In the process of adding better error messages for sorting, I realized
that strsep was being used incorrectly and some of the error paths I
was expecting to be hit weren't and just fell through to the common
invalid key error case.
It also became obvious that for keyword assignments, it wasn't
necessary to save the full assignment and reparse it later, and having
a common empty-assignment check would also make more sense in terms of
error processing.
Change the code to fix these problems and simplify it for new error
message changes in a subsequent patch.
Link: http://lkml.kernel.org/r/1c3ef0b6655deaf345f6faee2584a0298ac2d743.1561743018.git.zanussi@kernel.org
Fixes: e62347d245 ("tracing: Add hist trigger support for user-defined sorting ('sort=' param)")
Fixes: 7ef224d1d0 ("tracing: Add 'hist' event trigger command")
Fixes: a4072fe85b ("tracing: Add a clock attribute for hist triggers")
Reported-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Fix for time travel mode
- Disable CONFIG_CONSTRUCTORS again
- A new command line option to have an non-raw serial line
- Preparations to remove obsolete UML network drivers
-----BEGIN PGP SIGNATURE-----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=yi/o
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Anton Ivanov:
"I am sending this on behalf of Richard who is traveling.
This contains the following changes for UML:
- Fix for time travel mode
- Disable CONFIG_CONSTRUCTORS again
- A new command line option to have an non-raw serial line
- Preparations to remove obsolete UML network drivers"
* tag 'for-linus-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml:
um: Fix time-travel=inf-cpu with xor/raid6
Revert "um: Enable CONFIG_CONSTRUCTORS"
um: Mark non-vector net transports as obsolete
um: Add an option to make serial driver non-raw
or user space. But the creating of the event format file only checks for
"string" to display string formats. "ustring" must also be handled.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXi8JRxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qvaiAP943Srl0C1NHuKtJGHpYkgHJRt4mPFO
569Wx82a2ODH4AEA/D8uda0+p0wJB/uDnd/VyhTeb1nAjqzhx4pfGPNjaw8=
=lu3h
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Kprobe events added 'ustring' to distinguish reading strings from
kernel space or user space.
But the creating of the event format file only checks for 'string' to
display string formats. 'ustring' must also be handled"
* tag 'trace-v5.5-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/kprobes: Have uname use __get_str() in print_fmt
Pull networking updates from David Miller:
1) Add WireGuard
2) Add HE and TWT support to ath11k driver, from John Crispin.
3) Add ESP in TCP encapsulation support, from Sabrina Dubroca.
4) Add variable window congestion control to TIPC, from Jon Maloy.
5) Add BCM84881 PHY driver, from Russell King.
6) Start adding netlink support for ethtool operations, from Michal
Kubecek.
7) Add XDP drop and TX action support to ena driver, from Sameeh
Jubran.
8) Add new ipv4 route notifications so that mlxsw driver does not have
to handle identical routes itself. From Ido Schimmel.
9) Add BPF dynamic program extensions, from Alexei Starovoitov.
10) Support RX and TX timestamping in igc, from Vinicius Costa Gomes.
11) Add support for macsec HW offloading, from Antoine Tenart.
12) Add initial support for MPTCP protocol, from Christoph Paasch,
Matthieu Baerts, Florian Westphal, Peter Krystad, and many others.
13) Add Octeontx2 PF support, from Sunil Goutham, Geetha sowjanya, Linu
Cherian, and others.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1469 commits)
net: phy: add default ARCH_BCM_IPROC for MDIO_BCM_IPROC
udp: segment looped gso packets correctly
netem: change mailing list
qed: FW 8.42.2.0 debug features
qed: rt init valid initialization changed
qed: Debug feature: ilt and mdump
qed: FW 8.42.2.0 Add fw overlay feature
qed: FW 8.42.2.0 HSI changes
qed: FW 8.42.2.0 iscsi/fcoe changes
qed: Add abstraction for different hsi values per chip
qed: FW 8.42.2.0 Additional ll2 type
qed: Use dmae to write to widebus registers in fw_funcs
qed: FW 8.42.2.0 Parser offsets modified
qed: FW 8.42.2.0 Queue Manager changes
qed: FW 8.42.2.0 Expose new registers and change windows
qed: FW 8.42.2.0 Internal ram offsets modifications
MAINTAINERS: Add entry for Marvell OcteonTX2 Physical Function driver
Documentation: net: octeontx2: Add RVU HW and drivers overview
octeontx2-pf: ethtool RSS config support
octeontx2-pf: Add basic ethtool support
...
Pull crypto updates from Herbert Xu:
"API:
- Removed CRYPTO_TFM_RES flags
- Extended spawn grabbing to all algorithm types
- Moved hash descsize verification into API code
Algorithms:
- Fixed recursive pcrypt dead-lock
- Added new 32 and 64-bit generic versions of poly1305
- Added cryptogams implementation of x86/poly1305
Drivers:
- Added support for i.MX8M Mini in caam
- Added support for i.MX8M Nano in caam
- Added support for i.MX8M Plus in caam
- Added support for A33 variant of SS in sun4i-ss
- Added TEE support for Raven Ridge in ccp
- Added in-kernel API to submit TEE commands in ccp
- Added AMD-TEE driver
- Added support for BCM2711 in iproc-rng200
- Added support for AES256-GCM based ciphers for chtls
- Added aead support on SEC2 in hisilicon"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (244 commits)
crypto: arm/chacha - fix build failured when kernel mode NEON is disabled
crypto: caam - add support for i.MX8M Plus
crypto: x86/poly1305 - emit does base conversion itself
crypto: hisilicon - fix spelling mistake "disgest" -> "digest"
crypto: chacha20poly1305 - add back missing test vectors and test chunking
crypto: x86/poly1305 - fix .gitignore typo
tee: fix memory allocation failure checks on drv_data and amdtee
crypto: ccree - erase unneeded inline funcs
crypto: ccree - make cc_pm_put_suspend() void
crypto: ccree - split overloaded usage of irq field
crypto: ccree - fix PM race condition
crypto: ccree - fix FDE descriptor sequence
crypto: ccree - cc_do_send_request() is void func
crypto: ccree - fix pm wrongful error reporting
crypto: ccree - turn errors to debug msgs
crypto: ccree - fix AEAD decrypt auth fail
crypto: ccree - fix typo in comment
crypto: ccree - fix typos in error msgs
crypto: atmel-{aes,sha,tdes} - Retire crypto_platform_data
crypto: x86/sha - Eliminate casts on asm implementations
...
Group RT scheduler contains protection against setting zero runtime for
cgroup with RT tasks. Right now function tg_set_rt_bandwidth() iterates
over all CPU cgroups and calls tg_has_rt_tasks() for any cgroup which
runtime is zero (not only for changed one). Default RT runtime is zero,
thus tg_has_rt_tasks() will is called for almost at CPU cgroups.
This protection already is slightly racy: runtime limit could be changed
between cpu_cgroup_can_attach() and cpu_cgroup_attach() because changing
cgroup attribute does not lock cgroup_mutex while attach does not lock
rt_constraints_mutex. Changing task scheduler class also races with
changing rt runtime: check in __sched_setscheduler() isn't protected.
Function tg_has_rt_tasks() iterates over all threads in the system.
This gives NR_CGROUPS * NR_TASKS operations under single tasklist_lock
locked for read tg_set_rt_bandwidth(). Any concurrent attempt of locking
tasklist_lock for write (for example fork) will stuck with disabled irqs.
This patch makes two optimizations:
1) Remove locking tasklist_lock and iterate only tasks in cgroup
2) Call tg_has_rt_tasks() iff rt runtime changes from non-zero to zero
All changed code is under CONFIG_RT_GROUP_SCHED.
Testcase:
# mkdir /sys/fs/cgroup/cpu/test{1..10000}
# echo 0 | tee /sys/fs/cgroup/cpu/test*/cpu.rt_runtime_us
At the same time without patch fork time will be >100ms:
# perf trace -e clone --duration 100 stress-ng --fork 1
Also remote ping will show timings >100ms caused by irq latency.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/157996383820.4651.11292439232549211693.stgit@buzz
Currently we loop through all threads of a core to evaluate if the core is
idle or not. This is unnecessary. If a thread of a core is not idle, skip
evaluating other threads of a core. Also while clearing the cpumask, bits
of all CPUs of a core can be cleared in one-shot.
Collecting ticks on a Power 9 SMT 8 system around select_idle_core
while running schbench shows us
(units are in ticks, hence lesser is better)
Without patch
N Min Max Median Avg Stddev
x 130 151 1083 284 322.72308 144.41494
With patch
N Min Max Median Avg Stddev Improvement
x 164 88 610 201 225.79268 106.78943 30.03%
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Link: https://lkml.kernel.org/r/20191206172422.6578-1-srikar@linux.vnet.ibm.com
Implement arch_scale_freq_capacity() for 'modern' x86. This function
is used by the scheduler to correctly account usage in the face of
DVFS.
The present patch addresses Intel processors specifically and has positive
performance and performance-per-watt implications for the schedutil cpufreq
governor, bringing it closer to, if not on-par with, the powersave governor
from the intel_pstate driver/framework.
Large performance gains are obtained when the machine is lightly loaded and
no regression are observed at saturation. The benchmarks with the largest
gains are kernel compilation, tbench (the networking version of dbench) and
shell-intensive workloads.
1. FREQUENCY INVARIANCE: MOTIVATION
* Without it, a task looks larger if the CPU runs slower
2. PECULIARITIES OF X86
* freq invariance accounting requires knowing the ratio freq_curr/freq_max
2.1 CURRENT FREQUENCY
* Use delta_APERF / delta_MPERF * freq_base (a.k.a "BusyMHz")
2.2 MAX FREQUENCY
* It varies with time (turbo). As an approximation, we set it to a
constant, i.e. 4-cores turbo frequency.
3. EFFECTS ON THE SCHEDUTIL FREQUENCY GOVERNOR
* The invariant schedutil's formula has no feedback loop and reacts faster
to utilization changes
4. KNOWN LIMITATIONS
* In some cases tasks can't reach max util despite how hard they try
5. PERFORMANCE TESTING
5.1 MACHINES
* Skylake, Broadwell, Haswell
5.2 SETUP
* baseline Linux v5.2 w/ non-invariant schedutil. Tested freq_max = 1-2-3-4-8-12
active cores turbo w/ invariant schedutil, and intel_pstate/powersave
5.3 BENCHMARK RESULTS
5.3.1 NEUTRAL BENCHMARKS
* NAS Parallel Benchmark (HPC), hackbench
5.3.2 NON-NEUTRAL BENCHMARKS
* tbench (10-30% better), kernbench (10-15% better),
shell-intensive-scripts (30-50% better)
* no regressions
5.3.3 SELECTION OF DETAILED RESULTS
5.3.4 POWER CONSUMPTION, PERFORMANCE-PER-WATT
* dbench (5% worse on one machine), kernbench (3% worse),
tbench (5-10% better), shell-intensive-scripts (10-40% better)
6. MICROARCH'ES ADDRESSED HERE
* Xeon Core before Scalable Performance processors line (Xeon Gold/Platinum
etc have different MSRs semantic for querying turbo levels)
7. REFERENCES
* MMTests performance testing framework, github.com/gormanm/mmtests
+-------------------------------------------------------------------------+
| 1. FREQUENCY INVARIANCE: MOTIVATION
+-------------------------------------------------------------------------+
For example; suppose a CPU has two frequencies: 500 and 1000 Mhz. When
running a task that would consume 1/3rd of a CPU at 1000 MHz, it would
appear to consume 2/3rd (or 66.6%) when running at 500 MHz, giving the
false impression this CPU is almost at capacity, even though it can go
faster [*]. In a nutshell, without frequency scale-invariance tasks look
larger just because the CPU is running slower.
[*] (footnote: this assumes a linear frequency/performance relation; which
everybody knows to be false, but given realities its the best approximation
we can make.)
+-------------------------------------------------------------------------+
| 2. PECULIARITIES OF X86
+-------------------------------------------------------------------------+
Accounting for frequency changes in PELT signals requires the computation of
the ratio freq_curr / freq_max. On x86 neither of those terms is readily
available.
2.1 CURRENT FREQUENCY
====================
Since modern x86 has hardware control over the actual frequency we run
at (because amongst other things, Turbo-Mode), we cannot simply use
the frequency as requested through cpufreq.
Instead we use the APERF/MPERF MSRs to compute the effective frequency
over the recent past. Also, because reading MSRs is expensive, don't
do so every time we need the value, but amortize the cost by doing it
every tick.
2.2 MAX FREQUENCY
=================
Obtaining freq_max is also non-trivial because at any time the hardware can
provide a frequency boost to a selected subset of cores if the package has
enough power to spare (eg: Turbo Boost). This means that the maximum frequency
available to a given core changes with time.
The approach taken in this change is to arbitrarily set freq_max to a constant
value at boot. The value chosen is the "4-cores (4C) turbo frequency" on most
microarchitectures, after evaluating the following candidates:
* 1-core (1C) turbo frequency (the fastest turbo state available)
* around base frequency (a.k.a. max P-state)
* something in between, such as 4C turbo
To interpret these options, consider that this is the denominator in
freq_curr/freq_max, and that ratio will be used to scale PELT signals such as
util_avg and load_avg. A large denominator will undershoot (util_avg looks a
bit smaller than it really is), viceversa with a smaller denominator PELT
signals will tend to overshoot. Given that PELT drives frequency selection
in the schedutil governor, we will have:
freq_max set to | effect on DVFS
--------------------+------------------
1C turbo | power efficiency (lower freq choices)
base freq | performance (higher util_avg, higher freq requests)
4C turbo | a bit of both
4C turbo proves to be a good compromise in a number of benchmarks (see below).
+-------------------------------------------------------------------------+
| 3. EFFECTS ON THE SCHEDUTIL FREQUENCY GOVERNOR
+-------------------------------------------------------------------------+
Once an architecture implements a frequency scale-invariant utilization (the
PELT signal util_avg), schedutil switches its frequency selection formula from
freq_next = 1.25 * freq_curr * util [non-invariant util signal]
to
freq_next = 1.25 * freq_max * util [invariant util signal]
where, in the second formula, freq_max is set to the 1C turbo frequency (max
turbo). The advantage of the second formula, whose usage we unlock with this
patch, is that freq_next doesn't depend on the current frequency in an
iterative fashion, but can jump to any frequency in a single update. This
absence of feedback in the formula makes it quicker to react to utilization
changes and more robust against pathological instabilities.
Compare it to the update formula of intel_pstate/powersave:
freq_next = 1.25 * freq_max * Busy%
where again freq_max is 1C turbo and Busy% is the percentage of time not spent
idling (calculated with delta_MPERF / delta_TSC); essentially the same as
invariant schedutil, and largely responsible for intel_pstate/powersave good
reputation. The non-invariant schedutil formula is derived from the invariant
one by approximating util_inv with util_raw * freq_curr / freq_max, but this
has limitations.
Testing shows improved performances due to better frequency selections when
the machine is lightly loaded, and essentially no change in behaviour at
saturation / overutilization.
+-------------------------------------------------------------------------+
| 4. KNOWN LIMITATIONS
+-------------------------------------------------------------------------+
It's been shown that it is possible to create pathological scenarios where a
CPU-bound task cannot reach max utilization, if the normalizing factor
freq_max is fixed to a constant value (see [Lelli-2018]).
If freq_max is set to 4C turbo as we do here, one needs to peg at least 5
cores in a package doing some busywork, and observe that none of those task
will ever reach max util (1024) because they're all running at less than the
4C turbo frequency.
While this concern still applies, we believe the performance benefit of
frequency scale-invariant PELT signals outweights the cost of this limitation.
[Lelli-2018]
https://lore.kernel.org/lkml/20180517150418.GF22493@localhost.localdomain/
+-------------------------------------------------------------------------+
| 5. PERFORMANCE TESTING
+-------------------------------------------------------------------------+
5.1 MACHINES
============
We tested the patch on three machines, with Skylake, Broadwell and Haswell
CPUs. The details are below, together with the available turbo ratios as
reported by the appropriate MSRs.
* 8x-SKYLAKE-UMA:
Single socket E3-1240 v5, Skylake 4 cores/8 threads
Max EFFiciency, BASE frequency and available turbo levels (MHz):
EFFIC 800 |********
BASE 3500 |***********************************
4C 3700 |*************************************
3C 3800 |**************************************
2C 3900 |***************************************
1C 3900 |***************************************
* 80x-BROADWELL-NUMA:
Two sockets E5-2698 v4, 2x Broadwell 20 cores/40 threads
Max EFFiciency, BASE frequency and available turbo levels (MHz):
EFFIC 1200 |************
BASE 2200 |**********************
8C 2900 |*****************************
7C 3000 |******************************
6C 3100 |*******************************
5C 3200 |********************************
4C 3300 |*********************************
3C 3400 |**********************************
2C 3600 |************************************
1C 3600 |************************************
* 48x-HASWELL-NUMA
Two sockets E5-2670 v3, 2x Haswell 12 cores/24 threads
Max EFFiciency, BASE frequency and available turbo levels (MHz):
EFFIC 1200 |************
BASE 2300 |***********************
12C 2600 |**************************
11C 2600 |**************************
10C 2600 |**************************
9C 2600 |**************************
8C 2600 |**************************
7C 2600 |**************************
6C 2600 |**************************
5C 2700 |***************************
4C 2800 |****************************
3C 2900 |*****************************
2C 3100 |*******************************
1C 3100 |*******************************
5.2 SETUP
=========
* The baseline is Linux v5.2 with schedutil (non-invariant) and the intel_pstate
driver in passive mode.
* The rationale for choosing the various freq_max values to test have been to
try all the 1-2-3-4C turbo levels (note that 1C and 2C turbo are identical
on all machines), plus one more value closer to base_freq but still in the
turbo range (8C turbo for both 80x-BROADWELL-NUMA and 48x-HASWELL-NUMA).
* In addition we've run all tests with intel_pstate/powersave for comparison.
* The filesystem is always XFS, the userspace is openSUSE Leap 15.1.
* 8x-SKYLAKE-UMA is capable of HWP (Hardware-Managed P-States), so the runs
with active intel_pstate on this machine use that.
This gives, in terms of combinations tested on each machine:
* 8x-SKYLAKE-UMA
* Baseline: Linux v5.2, non-invariant schedutil, intel_pstate passive
* intel_pstate active + powersave + HWP
* invariant schedutil, freq_max = 1C turbo
* invariant schedutil, freq_max = 3C turbo
* invariant schedutil, freq_max = 4C turbo
* both 80x-BROADWELL-NUMA and 48x-HASWELL-NUMA
* [same as 8x-SKYLAKE-UMA, but no HWP capable]
* invariant schedutil, freq_max = 8C turbo
(which on 48x-HASWELL-NUMA is the same as 12C turbo, or "all cores turbo")
5.3 BENCHMARK RESULTS
=====================
5.3.1 NEUTRAL BENCHMARKS
------------------------
Tests that didn't show any measurable difference in performance on any of the
test machines between non-invariant schedutil and our patch are:
* NAS Parallel Benchmarks (NPB) using either MPI or openMP for IPC, any
computational kernel
* flexible I/O (FIO)
* hackbench (using threads or processes, and using pipes or sockets)
5.3.2 NON-NEUTRAL BENCHMARKS
----------------------------
What follow are summary tables where each benchmark result is given a score.
* A tilde (~) means a neutral result, i.e. no difference from baseline.
* Scores are computed with the ratio result_new / result_baseline, so a tilde
means a score of 1.00.
* The results in the score ratio are the geometric means of results running
the benchmark with different parameters (eg: for kernbench: using 1, 2, 4,
... number of processes; for pgbench: varying the number of clients, and so
on).
* The first three tables show higher-is-better kind of tests (i.e. measured in
operations/second), the subsequent three show lower-is-better kind of tests
(i.e. the workload is fixed and we measure elapsed time, think kernbench).
* "gitsource" is a name we made up for the test consisting in running the
entire unit tests suite of the Git SCM and measuring how long it takes. We
take it as a typical example of shell-intensive serialized workload.
* In the "I_PSTATE" column we have the results for intel_pstate/powersave. Other
columns show invariant schedutil for different values of freq_max. 4C turbo
is circled as it's the value we've chosen for the final implementation.
80x-BROADWELL-NUMA (comparison ratio; higher is better)
+------+
I_PSTATE 1C 3C | 4C | 8C
pgbench-ro 1.14 ~ ~ | 1.11 | 1.14
pgbench-rw ~ ~ ~ | ~ | ~
netperf-udp 1.06 ~ 1.06 | 1.05 | 1.07
netperf-tcp ~ 1.03 ~ | 1.01 | 1.02
tbench4 1.57 1.18 1.22 | 1.30 | 1.56
+------+
8x-SKYLAKE-UMA (comparison ratio; higher is better)
+------+
I_PSTATE/HWP 1C 3C | 4C |
pgbench-ro ~ ~ ~ | ~ |
pgbench-rw ~ ~ ~ | ~ |
netperf-udp ~ ~ ~ | ~ |
netperf-tcp ~ ~ ~ | ~ |
tbench4 1.30 1.14 1.14 | 1.16 |
+------+
48x-HASWELL-NUMA (comparison ratio; higher is better)
+------+
I_PSTATE 1C 3C | 4C | 12C
pgbench-ro 1.15 ~ ~ | 1.06 | 1.16
pgbench-rw ~ ~ ~ | ~ | ~
netperf-udp 1.05 0.97 1.04 | 1.04 | 1.02
netperf-tcp 0.96 1.01 1.01 | 1.01 | 1.01
tbench4 1.50 1.05 1.13 | 1.13 | 1.25
+------+
In the table above we see that active intel_pstate is slightly better than our
4C-turbo patch (both in reference to the baseline non-invariant schedutil) on
read-only pgbench and much better on tbench. Both cases are notable in which
it shows that lowering our freq_max (to 8C-turbo and 12C-turbo on
80x-BROADWELL-NUMA and 48x-HASWELL-NUMA respectively) helps invariant
schedutil to get closer.
If we ignore active intel_pstate and focus on the comparison with baseline
alone, there are several instances of double-digit performance improvement.
80x-BROADWELL-NUMA (comparison ratio; lower is better)
+------+
I_PSTATE 1C 3C | 4C | 8C
dbench4 1.23 0.95 0.95 | 0.95 | 0.95
kernbench 0.93 0.83 0.83 | 0.83 | 0.82
gitsource 0.98 0.49 0.49 | 0.49 | 0.48
+------+
8x-SKYLAKE-UMA (comparison ratio; lower is better)
+------+
I_PSTATE/HWP 1C 3C | 4C |
dbench4 ~ ~ ~ | ~ |
kernbench ~ ~ ~ | ~ |
gitsource 0.92 0.55 0.55 | 0.55 |
+------+
48x-HASWELL-NUMA (comparison ratio; lower is better)
+------+
I_PSTATE 1C 3C | 4C | 8C
dbench4 ~ ~ ~ | ~ | ~
kernbench 0.94 0.90 0.89 | 0.90 | 0.90
gitsource 0.97 0.69 0.69 | 0.69 | 0.69
+------+
dbench is not very remarkable here, unless we notice how poorly active
intel_pstate is performing on 80x-BROADWELL-NUMA: 23% regression versus
non-invariant schedutil. We repeated that run getting consistent results. Out
of scope for the patch at hand, but deserving future investigation. Other than
that, we previously ran this campaign with Linux v5.0 and saw the patch doing
better on dbench a the time. We haven't checked closely and can only speculate
at this point.
On the NUMA boxes kernbench gets 10-15% improvements on average; we'll see in
the detailed tables that the gains concentrate on low process counts (lightly
loaded machines).
The test we call "gitsource" (running the git unit test suite, a long-running
single-threaded shell script) appears rather spectacular in this table (gains
of 30-50% depending on the machine). It is to be noted, however, that
gitsource has no adjustable parameters (such as the number of jobs in
kernbench, which we average over in order to get a single-number summary
score) and is exactly the kind of low-parallelism workload that benefits the
most from this patch. When looking at the detailed tables of kernbench or
tbench4, at low process or client counts one can see similar numbers.
5.3.3 SELECTION OF DETAILED RESULTS
-----------------------------------
Machine : 48x-HASWELL-NUMA
Benchmark : tbench4 (i.e. dbench4 over the network, actually loopback)
Varying parameter : number of clients
Unit : MB/sec (higher is better)
5.2.0 vanilla (BASELINE) 5.2.0 intel_pstate 5.2.0 1C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean 1 126.73 +- 0.31% ( ) 315.91 +- 0.66% ( 149.28%) 125.03 +- 0.76% ( -1.34%)
Hmean 2 258.04 +- 0.62% ( ) 614.16 +- 0.51% ( 138.01%) 269.58 +- 1.45% ( 4.47%)
Hmean 4 514.30 +- 0.67% ( ) 1146.58 +- 0.54% ( 122.94%) 533.84 +- 1.99% ( 3.80%)
Hmean 8 1111.38 +- 2.52% ( ) 2159.78 +- 0.38% ( 94.33%) 1359.92 +- 1.56% ( 22.36%)
Hmean 16 2286.47 +- 1.36% ( ) 3338.29 +- 0.21% ( 46.00%) 2720.20 +- 0.52% ( 18.97%)
Hmean 32 4704.84 +- 0.35% ( ) 4759.03 +- 0.43% ( 1.15%) 4774.48 +- 0.30% ( 1.48%)
Hmean 64 7578.04 +- 0.27% ( ) 7533.70 +- 0.43% ( -0.59%) 7462.17 +- 0.65% ( -1.53%)
Hmean 128 6998.52 +- 0.16% ( ) 6987.59 +- 0.12% ( -0.16%) 6909.17 +- 0.14% ( -1.28%)
Hmean 192 6901.35 +- 0.25% ( ) 6913.16 +- 0.10% ( 0.17%) 6855.47 +- 0.21% ( -0.66%)
5.2.0 3C-turbo 5.2.0 4C-turbo 5.2.0 12C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Hmean 1 128.43 +- 0.28% ( 1.34%) 130.64 +- 3.81% ( 3.09%) 153.71 +- 5.89% ( 21.30%)
Hmean 2 311.70 +- 6.15% ( 20.79%) 281.66 +- 3.40% ( 9.15%) 305.08 +- 5.70% ( 18.23%)
Hmean 4 641.98 +- 2.32% ( 24.83%) 623.88 +- 5.28% ( 21.31%) 906.84 +- 4.65% ( 76.32%)
Hmean 8 1633.31 +- 1.56% ( 46.96%) 1714.16 +- 0.93% ( 54.24%) 2095.74 +- 0.47% ( 88.57%)
Hmean 16 3047.24 +- 0.42% ( 33.27%) 3155.02 +- 0.30% ( 37.99%) 3634.58 +- 0.15% ( 58.96%)
Hmean 32 4734.31 +- 0.60% ( 0.63%) 4804.38 +- 0.23% ( 2.12%) 4674.62 +- 0.27% ( -0.64%)
Hmean 64 7699.74 +- 0.35% ( 1.61%) 7499.72 +- 0.34% ( -1.03%) 7659.03 +- 0.25% ( 1.07%)
Hmean 128 6935.18 +- 0.15% ( -0.91%) 6942.54 +- 0.10% ( -0.80%) 7004.85 +- 0.12% ( 0.09%)
Hmean 192 6901.62 +- 0.12% ( 0.00%) 6856.93 +- 0.10% ( -0.64%) 6978.74 +- 0.10% ( 1.12%)
This is one of the cases where the patch still can't surpass active
intel_pstate, not even when freq_max is as low as 12C-turbo. Otherwise, gains are
visible up to 16 clients and the saturated scenario is the same as baseline.
The scores in the summary table from the previous sections are ratios of
geometric means of the results over different clients, as seen in this table.
Machine : 80x-BROADWELL-NUMA
Benchmark : kernbench (kernel compilation)
Varying parameter : number of jobs
Unit : seconds (lower is better)
5.2.0 vanilla (BASELINE) 5.2.0 intel_pstate 5.2.0 1C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 2 379.68 +- 0.06% ( ) 330.20 +- 0.43% ( 13.03%) 285.93 +- 0.07% ( 24.69%)
Amean 4 200.15 +- 0.24% ( ) 175.89 +- 0.22% ( 12.12%) 153.78 +- 0.25% ( 23.17%)
Amean 8 106.20 +- 0.31% ( ) 95.54 +- 0.23% ( 10.03%) 86.74 +- 0.10% ( 18.32%)
Amean 16 56.96 +- 1.31% ( ) 53.25 +- 1.22% ( 6.50%) 48.34 +- 1.73% ( 15.13%)
Amean 32 34.80 +- 2.46% ( ) 33.81 +- 0.77% ( 2.83%) 30.28 +- 1.59% ( 12.99%)
Amean 64 26.11 +- 1.63% ( ) 25.04 +- 1.07% ( 4.10%) 22.41 +- 2.37% ( 14.16%)
Amean 128 24.80 +- 1.36% ( ) 23.57 +- 1.23% ( 4.93%) 21.44 +- 1.37% ( 13.55%)
Amean 160 24.85 +- 0.56% ( ) 23.85 +- 1.17% ( 4.06%) 21.25 +- 1.12% ( 14.49%)
5.2.0 3C-turbo 5.2.0 4C-turbo 5.2.0 8C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 2 284.08 +- 0.13% ( 25.18%) 283.96 +- 0.51% ( 25.21%) 285.05 +- 0.21% ( 24.92%)
Amean 4 153.18 +- 0.22% ( 23.47%) 154.70 +- 1.64% ( 22.71%) 153.64 +- 0.30% ( 23.24%)
Amean 8 87.06 +- 0.28% ( 18.02%) 86.77 +- 0.46% ( 18.29%) 86.78 +- 0.22% ( 18.28%)
Amean 16 48.03 +- 0.93% ( 15.68%) 47.75 +- 1.99% ( 16.17%) 47.52 +- 1.61% ( 16.57%)
Amean 32 30.23 +- 1.20% ( 13.14%) 30.08 +- 1.67% ( 13.57%) 30.07 +- 1.67% ( 13.60%)
Amean 64 22.59 +- 2.02% ( 13.50%) 22.63 +- 0.81% ( 13.32%) 22.42 +- 0.76% ( 14.12%)
Amean 128 21.37 +- 0.67% ( 13.82%) 21.31 +- 1.15% ( 14.07%) 21.17 +- 1.93% ( 14.63%)
Amean 160 21.68 +- 0.57% ( 12.76%) 21.18 +- 1.74% ( 14.77%) 21.22 +- 1.00% ( 14.61%)
The patch outperform active intel_pstate (and baseline) by a considerable
margin; the summary table from the previous section says 4C turbo and active
intel_pstate are 0.83 and 0.93 against baseline respectively, so 4C turbo is
0.83/0.93=0.89 against intel_pstate (~10% better on average). There is no
noticeable difference with regard to the value of freq_max.
Machine : 8x-SKYLAKE-UMA
Benchmark : gitsource (time to run the git unit test suite)
Varying parameter : none
Unit : seconds (lower is better)
5.2.0 vanilla 5.2.0 intel_pstate/hwp 5.2.0 1C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 858.85 +- 1.16% ( ) 791.94 +- 0.21% ( 7.79%) 474.95 ( 44.70%)
5.2.0 3C-turbo 5.2.0 4C-turbo
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Amean 475.26 +- 0.20% ( 44.66%) 474.34 +- 0.13% ( 44.77%)
In this test, which is of interest as representing shell-intensive
(i.e. fork-intensive) serialized workloads, invariant schedutil outperforms
intel_pstate/powersave by a whopping 40% margin.
5.3.4 POWER CONSUMPTION, PERFORMANCE-PER-WATT
---------------------------------------------
The following table shows average power consumption in watt for each
benchmark. Data comes from turbostat (package average), which in turn is read
from the RAPL interface on CPUs. We know the patch affects CPU frequencies so
it's reasonable to ignore other power consumers (such as memory or I/O). Also,
we don't have a power meter available in the lab so RAPL is the best we have.
turbostat sampled average power every 10 seconds for the entire duration of
each benchmark. We took all those values and averaged them (i.e. with don't
have detail on a per-parameter granularity, only on whole benchmarks).
80x-BROADWELL-NUMA (power consumption, watts)
+--------+
BASELINE I_PSTATE 1C 3C | 4C | 8C
pgbench-ro 130.01 142.77 131.11 132.45 | 134.65 | 136.84
pgbench-rw 68.30 60.83 71.45 71.70 | 71.65 | 72.54
dbench4 90.25 59.06 101.43 99.89 | 101.10 | 102.94
netperf-udp 65.70 69.81 66.02 68.03 | 68.27 | 68.95
netperf-tcp 88.08 87.96 88.97 88.89 | 88.85 | 88.20
tbench4 142.32 176.73 153.02 163.91 | 165.58 | 176.07
kernbench 92.94 101.95 114.91 115.47 | 115.52 | 115.10
gitsource 40.92 41.87 75.14 75.20 | 75.40 | 75.70
+--------+
8x-SKYLAKE-UMA (power consumption, watts)
+--------+
BASELINE I_PSTATE/HWP 1C 3C | 4C |
pgbench-ro 46.49 46.68 46.56 46.59 | 46.52 |
pgbench-rw 29.34 31.38 30.98 31.00 | 31.00 |
dbench4 27.28 27.37 27.49 27.41 | 27.38 |
netperf-udp 22.33 22.41 22.36 22.35 | 22.36 |
netperf-tcp 27.29 27.29 27.30 27.31 | 27.33 |
tbench4 41.13 45.61 43.10 43.33 | 43.56 |
kernbench 42.56 42.63 43.01 43.01 | 43.01 |
gitsource 13.32 13.69 17.33 17.30 | 17.35 |
+--------+
48x-HASWELL-NUMA (power consumption, watts)
+--------+
BASELINE I_PSTATE 1C 3C | 4C | 12C
pgbench-ro 128.84 136.04 129.87 132.43 | 132.30 | 134.86
pgbench-rw 37.68 37.92 37.17 37.74 | 37.73 | 37.31
dbench4 28.56 28.73 28.60 28.73 | 28.70 | 28.79
netperf-udp 56.70 60.44 56.79 57.42 | 57.54 | 57.52
netperf-tcp 75.49 75.27 75.87 76.02 | 76.01 | 75.95
tbench4 115.44 139.51 119.53 123.07 | 123.97 | 130.22
kernbench 83.23 91.55 95.58 95.69 | 95.72 | 96.04
gitsource 36.79 36.99 39.99 40.34 | 40.35 | 40.23
+--------+
A lower power consumption isn't necessarily better, it depends on what is done
with that energy. Here are tables with the ratio of performance-per-watt on
each machine and benchmark. Higher is always better; a tilde (~) means a
neutral ratio (i.e. 1.00).
80x-BROADWELL-NUMA (performance-per-watt ratios; higher is better)
+------+
I_PSTATE 1C 3C | 4C | 8C
pgbench-ro 1.04 1.06 0.94 | 1.07 | 1.08
pgbench-rw 1.10 0.97 0.96 | 0.96 | 0.97
dbench4 1.24 0.94 0.95 | 0.94 | 0.92
netperf-udp ~ 1.02 1.02 | ~ | 1.02
netperf-tcp ~ 1.02 ~ | ~ | 1.02
tbench4 1.26 1.10 1.06 | 1.12 | 1.26
kernbench 0.98 0.97 0.97 | 0.97 | 0.98
gitsource ~ 1.11 1.11 | 1.11 | 1.13
+------+
8x-SKYLAKE-UMA (performance-per-watt ratios; higher is better)
+------+
I_PSTATE/HWP 1C 3C | 4C |
pgbench-ro ~ ~ ~ | ~ |
pgbench-rw 0.95 0.97 0.96 | 0.96 |
dbench4 ~ ~ ~ | ~ |
netperf-udp ~ ~ ~ | ~ |
netperf-tcp ~ ~ ~ | ~ |
tbench4 1.17 1.09 1.08 | 1.10 |
kernbench ~ ~ ~ | ~ |
gitsource 1.06 1.40 1.40 | 1.40 |
+------+
48x-HASWELL-NUMA (performance-per-watt ratios; higher is better)
+------+
I_PSTATE 1C 3C | 4C | 12C
pgbench-ro 1.09 ~ 1.09 | 1.03 | 1.11
pgbench-rw ~ 0.86 ~ | ~ | 0.86
dbench4 ~ 1.02 1.02 | 1.02 | ~
netperf-udp ~ 0.97 1.03 | 1.02 | ~
netperf-tcp 0.96 ~ ~ | ~ | ~
tbench4 1.24 ~ 1.06 | 1.05 | 1.11
kernbench 0.97 0.97 0.98 | 0.97 | 0.96
gitsource 1.03 1.33 1.32 | 1.32 | 1.33
+------+
These results are overall pleasing: in plenty of cases we observe
performance-per-watt improvements. The few regressions (read/write pgbench and
dbench on the Broadwell machine) are of small magnitude. kernbench loses a few
percentage points (it has a 10-15% performance improvement, but apparently the
increase in power consumption is larger than that). tbench4 and gitsource, which
benefit the most from the patch, keep a positive score in this table which is
a welcome surprise; that suggests that in those particular workloads the
non-invariant schedutil (and active intel_pstate, too) makes some rather
suboptimal frequency selections.
+-------------------------------------------------------------------------+
| 6. MICROARCH'ES ADDRESSED HERE
+-------------------------------------------------------------------------+
The patch addresses Xeon Core processors that use MSR_PLATFORM_INFO and
MSR_TURBO_RATIO_LIMIT to advertise their base frequency and turbo frequencies
respectively. This excludes the recent Xeon Scalable Performance processors
line (Xeon Gold, Platinum etc) whose MSRs have to be parsed differently.
Subsequent patches will address:
* Xeon Scalable Performance processors and Atom Goldmont/Goldmont Plus
* Xeon Phi (Knights Landing, Knights Mill)
* Atom Silvermont
+-------------------------------------------------------------------------+
| 7. REFERENCES
+-------------------------------------------------------------------------+
Tests have been run with the help of the MMTests performance testing
framework, see github.com/gormanm/mmtests. The configuration file names for
the benchmark used are:
db-pgbench-timed-ro-small-xfs
db-pgbench-timed-rw-small-xfs
io-dbench4-async-xfs
network-netperf-unbound
network-tbench
scheduler-unbound
workload-kerndevel-xfs
workload-shellscripts-xfs
hpc-nas-c-class-mpi-full-xfs
hpc-nas-c-class-omp-full
All those benchmarks are generally available on the web:
pgbench: https://www.postgresql.org/docs/10/pgbench.html
netperf: https://hewlettpackard.github.io/netperf/
dbench/tbench: https://dbench.samba.org/
gitsource: git unit test suite, github.com/git/git
NAS Parallel Benchmarks: https://www.nas.nasa.gov/publications/npb.html
hackbench: https://people.redhat.com/mingo/cfs-scheduler/tools/hackbench.c
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Giovanni Gherdovich <ggherdovich@suse.cz>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Doug Smythies <dsmythies@telus.net>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/20200122151617.531-2-ggherdovich@suse.cz
When a running task is moved on a throttled task group and there is no
other task enqueued on the CPU, the task can keep running using 100% CPU
whatever the allocated bandwidth for the group and although its cfs rq is
throttled. Furthermore, the group entity of the cfs_rq and its parents are
not enqueued but only set as curr on their respective cfs_rqs.
We have the following sequence:
sched_move_task
-dequeue_task: dequeue task and group_entities.
-put_prev_task: put task and group entities.
-sched_change_group: move task to new group.
-enqueue_task: enqueue only task but not group entities because cfs_rq is
throttled.
-set_next_task : set task and group_entities as current sched_entity of
their cfs_rq.
Another impact is that the root cfs_rq runnable_load_avg at root rq stays
null because the group_entities are not enqueued. This situation will stay
the same until an "external" event triggers a reschedule. Let trigger it
immediately instead.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Ben Segall <bsegall@google.com>
Link: https://lkml.kernel.org/r/1579011236-31256-1-git-send-email-vincent.guittot@linaro.org
On a machine, CPU 0 is used for housekeeping, the other 39 CPUs in the
same socket are in nohz_full mode. We can observe huge time burn in the
loop for seaching nearest busy housekeeper cpu by ftrace.
2) | get_nohz_timer_target() {
2) 0.240 us | housekeeping_test_cpu();
2) 0.458 us | housekeeping_test_cpu();
...
2) 0.292 us | housekeeping_test_cpu();
2) 0.240 us | housekeeping_test_cpu();
2) 0.227 us | housekeeping_any_cpu();
2) + 43.460 us | }
This patch optimizes the searching logic by finding a nearest housekeeper
CPU in the housekeeping cpumask, it can minimize the worst searching time
from ~44us to < 10us in my testing. In addition, the last iterated busy
housekeeper can become a random candidate while current CPU is a better
fallback if it is a housekeeper.
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/1578876627-11938-1-git-send-email-wanpengli@tencent.com
The check to ensure that the new written value into cpu.uclamp.{min,max}
is within range, [0:100], wasn't working because of the signed
comparison
7301 if (req.percent > UCLAMP_PERCENT_SCALE) {
7302 req.ret = -ERANGE;
7303 return req;
7304 }
# echo -1 > cpu.uclamp.min
# cat cpu.uclamp.min
42949671.96
Cast req.percent into u64 to force the comparison to be unsigned and
work as intended in capacity_from_percent().
# echo -1 > cpu.uclamp.min
sh: write error: Numerical result out of range
Fixes: 2480c09313 ("sched/uclamp: Extend CPU's cgroup controller")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200114210947.14083-1-qais.yousef@arm.com
The CPU load balancer balances between different domains to spread load
and strives to have equal balance everywhere. Communicating tasks can
migrate so they are topologically close to each other but these decisions
are independent. On a lightly loaded NUMA machine, two communicating tasks
pulled together at wakeup time can be pushed apart by the load balancer.
In isolation, the load balancer decision is fine but it ignores the tasks
data locality and the wakeup/LB paths continually conflict. NUMA balancing
is also a factor but it also simply conflicts with the load balancer.
This patch allows a fixed degree of imbalance of two tasks to exist
between NUMA domains regardless of utilisation levels. In many cases,
this prevents communicating tasks being pulled apart. It was evaluated
whether the imbalance should be scaled to the domain size. However, no
additional benefit was measured across a range of workloads and machines
and scaling adds the risk that lower domains have to be rebalanced. While
this could change again in the future, such a change should specify the
use case and benefit.
The most obvious impact is on netperf TCP_STREAM -- two simple
communicating tasks with some softirq offload depending on the
transmission rate.
2-socket Haswell machine 48 core, HT enabled
netperf-tcp -- mmtests config config-network-netperf-unbound
baseline lbnuma-v3
Hmean 64 568.73 ( 0.00%) 577.56 * 1.55%*
Hmean 128 1089.98 ( 0.00%) 1128.06 * 3.49%*
Hmean 256 2061.72 ( 0.00%) 2104.39 * 2.07%*
Hmean 1024 7254.27 ( 0.00%) 7557.52 * 4.18%*
Hmean 2048 11729.20 ( 0.00%) 13350.67 * 13.82%*
Hmean 3312 15309.08 ( 0.00%) 18058.95 * 17.96%*
Hmean 4096 17338.75 ( 0.00%) 20483.66 * 18.14%*
Hmean 8192 25047.12 ( 0.00%) 27806.84 * 11.02%*
Hmean 16384 27359.55 ( 0.00%) 33071.88 * 20.88%*
Stddev 64 2.16 ( 0.00%) 2.02 ( 6.53%)
Stddev 128 2.31 ( 0.00%) 2.19 ( 5.05%)
Stddev 256 11.88 ( 0.00%) 3.22 ( 72.88%)
Stddev 1024 23.68 ( 0.00%) 7.24 ( 69.43%)
Stddev 2048 79.46 ( 0.00%) 71.49 ( 10.03%)
Stddev 3312 26.71 ( 0.00%) 57.80 (-116.41%)
Stddev 4096 185.57 ( 0.00%) 96.15 ( 48.19%)
Stddev 8192 245.80 ( 0.00%) 100.73 ( 59.02%)
Stddev 16384 207.31 ( 0.00%) 141.65 ( 31.67%)
In this case, there was a sizable improvement to performance and
a general reduction in variance. However, this is not univeral.
For most machines, the impact was roughly a 3% performance gain.
Ops NUMA base-page range updates 19796.00 292.00
Ops NUMA PTE updates 19796.00 292.00
Ops NUMA PMD updates 0.00 0.00
Ops NUMA hint faults 16113.00 143.00
Ops NUMA hint local faults % 8407.00 142.00
Ops NUMA hint local percent 52.18 99.30
Ops NUMA pages migrated 4244.00 1.00
Without the patch, only 52.18% of sampled accesses are local. In an
earlier changelog, 100% of sampled accesses are local and indeed on
most machines, this was still the case. In this specific case, the
local sampled rates was 99.3% but note the "base-page range updates"
and "PTE updates". The activity with the patch is negligible as were
the number of faults. The small number of pages migrated were related to
shared libraries. A 2-socket Broadwell showed better results on average
but are not presented for brevity as the performance was similar except
it showed 100% of the sampled NUMA hints were local. The patch holds up
for a 4-socket Haswell, an AMD EPYC and AMD Epyc 2 machine.
For dbench, the impact depends on the filesystem used and the number of
clients. On XFS, there is little difference as the clients typically
communicate with workqueues which have a separate class of scheduler
problem at the moment. For ext4, performance is generally better,
particularly for small numbers of clients as NUMA balancing activity is
negligible with the patch applied.
A more interesting example is the Facebook schbench which uses a
number of messaging threads to communicate with worker threads. In this
configuration, one messaging thread is used per NUMA node and the number of
worker threads is varied. The 50, 75, 90, 95, 99, 99.5 and 99.9 percentiles
for response latency is then reported.
Lat 50.00th-qrtle-1 44.00 ( 0.00%) 37.00 ( 15.91%)
Lat 75.00th-qrtle-1 53.00 ( 0.00%) 41.00 ( 22.64%)
Lat 90.00th-qrtle-1 57.00 ( 0.00%) 42.00 ( 26.32%)
Lat 95.00th-qrtle-1 63.00 ( 0.00%) 43.00 ( 31.75%)
Lat 99.00th-qrtle-1 76.00 ( 0.00%) 51.00 ( 32.89%)
Lat 99.50th-qrtle-1 89.00 ( 0.00%) 52.00 ( 41.57%)
Lat 99.90th-qrtle-1 98.00 ( 0.00%) 55.00 ( 43.88%)
Lat 50.00th-qrtle-2 42.00 ( 0.00%) 42.00 ( 0.00%)
Lat 75.00th-qrtle-2 48.00 ( 0.00%) 47.00 ( 2.08%)
Lat 90.00th-qrtle-2 53.00 ( 0.00%) 52.00 ( 1.89%)
Lat 95.00th-qrtle-2 55.00 ( 0.00%) 53.00 ( 3.64%)
Lat 99.00th-qrtle-2 62.00 ( 0.00%) 60.00 ( 3.23%)
Lat 99.50th-qrtle-2 63.00 ( 0.00%) 63.00 ( 0.00%)
Lat 99.90th-qrtle-2 68.00 ( 0.00%) 66.00 ( 2.94%
For higher worker threads, the differences become negligible but it's
interesting to note the difference in wakeup latency at low utilisation
and mpstat confirms that activity was almost all on one node until
the number of worker threads increase.
Hackbench generally showed neutral results across a range of machines.
This is different to earlier versions of the patch which allowed imbalances
for higher degrees of utilisation. perf bench pipe showed negligible
differences in overall performance as the differences are very close to
the noise.
An earlier prototype of the patch showed major regressions for NAS C-class
when running with only half of the available CPUs -- 20-30% performance
hits were measured at the time. With this version of the patch, the impact
is negligible with small gains/losses within the noise measured. This is
because the number of threads far exceeds the small imbalance the aptch
cares about. Similarly, there were report of regressions for the autonuma
benchmark against earlier versions but again, normal load balancing now
applies for that workload.
In general, the patch simply seeks to avoid unnecessary cross-node
migrations in the basic case where imbalances are very small. For low
utilisation communicating workloads, this patch generally behaves better
with less NUMA balancing activity. For high utilisation, there is no
change in behaviour.
Signed-off-by: Mel Gorman <mgorman@techsingularity.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Phil Auld <pauld@redhat.com>
Tested-by: Phil Auld <pauld@redhat.com>
Link: https://lkml.kernel.org/r/20200114101319.GO3466@techsingularity.net
The way loadavg is tracked during nohz only pays attention to the load
upon entering nohz. This can be particularly noticeable if full nohz is
entered while non-idle, and then the cpu goes idle and stays that way for
a long time.
Use the remote tick to ensure that full nohz cpus report their deltas
within a reasonable time.
[ swood: Added changelog and removed recheck of stopped tick. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Scott Wood <swood@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/1578736419-14628-3-git-send-email-swood@redhat.com
This will be used in the next patch to get a loadavg update from
nohz cpus. The delta check is skipped because idle_sched_class
doesn't update se.exec_start.
Signed-off-by: Scott Wood <swood@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/1578736419-14628-2-git-send-email-swood@redhat.com
cgroup events are always installed in the cpuctx. However, when it is not
installed via IPI, list_update_cgroup_event() adds it to cpuctx of current
CPU, which triggers list corruption:
[] list_add double add: new=ffff888ff7cf0db0, prev=ffff888ff7ce82f0, next=ffff888ff7cf0db0.
To reproduce this, we can simply run:
# perf stat -e cs -a &
# perf stat -e cs -G anycgroup
Fix this by installing it to cpuctx that contains event->ctx, and the
proper cgrp_cpuctx_list.
Fixes: db0503e4f6 ("perf/core: Optimize perf_install_in_event()")
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20200122195027.2112449-1-songliubraving@fb.com
Decreasing sysctl_perf_event_mlock between two consecutive perf_mmap()s of
a perf ring buffer may lead to an integer underflow in locked memory
accounting. This may lead to the undesired behaviors, such as failures in
BPF map creation.
Address this by adjusting the accounting logic to take into account the
possibility that the amount of already locked memory may exceed the
current limit.
Fixes: c4b7547974 ("perf/core: Make the mlock accounting simple again")
Suggested-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/20200123181146.2238074-1-songliubraving@fb.com
Pull scheduler updates from Ingo Molnar:
"These were the main changes in this cycle:
- More -rt motivated separation of CONFIG_PREEMPT and
CONFIG_PREEMPTION.
- Add more low level scheduling topology sanity checks and warnings
to filter out nonsensical topologies that break scheduling.
- Extend uclamp constraints to influence wakeup CPU placement
- Make the RT scheduler more aware of asymmetric topologies and CPU
capacities, via uclamp metrics, if CONFIG_UCLAMP_TASK=y
- Make idle CPU selection more consistent
- Various fixes, smaller cleanups, updates and enhancements - please
see the git log for details"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (58 commits)
sched/fair: Define sched_idle_cpu() only for SMP configurations
sched/topology: Assert non-NUMA topology masks don't (partially) overlap
idle: fix spelling mistake "iterrupts" -> "interrupts"
sched/fair: Remove redundant call to cpufreq_update_util()
sched/psi: create /proc/pressure and /proc/pressure/{io|memory|cpu} only when psi enabled
sched/fair: Fix sgc->{min,max}_capacity calculation for SD_OVERLAP
sched/fair: calculate delta runnable load only when it's needed
sched/cputime: move rq parameter in irqtime_account_process_tick
stop_machine: Make stop_cpus() static
sched/debug: Reset watchdog on all CPUs while processing sysrq-t
sched/core: Fix size of rq::uclamp initialization
sched/uclamp: Fix a bug in propagating uclamp value in new cgroups
sched/fair: Load balance aggressively for SCHED_IDLE CPUs
sched/fair : Improve update_sd_pick_busiest for spare capacity case
watchdog: Remove soft_lockup_hrtimer_cnt and related code
sched/rt: Make RT capacity-aware
sched/fair: Make EAS wakeup placement consider uclamp restrictions
sched/fair: Make task_fits_capacity() consider uclamp restrictions
sched/uclamp: Rename uclamp_util_with() into uclamp_rq_util_with()
sched/uclamp: Make uclamp util helpers use and return UL values
...
Pull perf updates from Ingo Molnar:
"Kernel side changes:
- Ftrace is one of the last W^X violators (after this only KLP is
left). These patches move it over to the generic text_poke()
interface and thereby get rid of this oddity. This requires a
surprising amount of surgery, by Peter Zijlstra.
- x86/AMD PMUs: add support for 'Large Increment per Cycle Events' to
count certain types of events that have a special, quirky hw ABI
(by Kim Phillips)
- kprobes fixes by Masami Hiramatsu
Lots of tooling updates as well, the following subcommands were
updated: annotate/report/top, c2c, clang, record, report/top TUI,
sched timehist, tests; plus updates were done to the gtk ui, libperf,
headers and the parser"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (57 commits)
perf/x86/amd: Add support for Large Increment per Cycle Events
perf/x86/amd: Constrain Large Increment per Cycle events
perf/x86/intel/rapl: Add Comet Lake support
tracing: Initialize ret in syscall_enter_define_fields()
perf header: Use last modification time for timestamp
perf c2c: Fix return type for histogram sorting comparision functions
perf beauty sockaddr: Fix augmented syscall format warning
perf/ui/gtk: Fix gtk2 build
perf ui gtk: Add missing zalloc object
perf tools: Use %define api.pure full instead of %pure-parser
libperf: Setup initial evlist::all_cpus value
perf report: Fix no libunwind compiled warning break s390 issue
perf tools: Support --prefix/--prefix-strip
perf report: Clarify in help that --children is default
tools build: Fix test-clang.cpp with Clang 8+
perf clang: Fix build with Clang 9
kprobes: Fix optimize_kprobe()/unoptimize_kprobe() cancellation logic
tools lib: Fix builds when glibc contains strlcpy()
perf report/top: Make 'e' visible in the help and make it toggle showing callchains
perf report/top: Do not offer annotation for symbols without samples
...
Pull locking updates from Ingo Molnar:
"Just a handful of changes in this cycle: an ARM64 performance
optimization, a comment fix and a debug output fix"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/osq: Use optimized spinning loop for arm64
locking/qspinlock: Fix inaccessible URL of MCS lock paper
locking/lockdep: Fix lockdep_stats indentation problem
Pull RCU updates from Ingo Molnar:
"The RCU changes in this cycle were:
- Expedited grace-period updates
- kfree_rcu() updates
- RCU list updates
- Preemptible RCU updates
- Torture-test updates
- Miscellaneous fixes
- Documentation updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (69 commits)
rcu: Remove unused stop-machine #include
powerpc: Remove comment about read_barrier_depends()
.mailmap: Add entries for old paulmck@kernel.org addresses
srcu: Apply *_ONCE() to ->srcu_last_gp_end
rcu: Switch force_qs_rnp() to for_each_leaf_node_cpu_mask()
rcu: Move rcu_{expedited,normal} definitions into rcupdate.h
rcu: Move gp_state_names[] and gp_state_getname() to tree_stall.h
rcu: Remove the declaration of call_rcu() in tree.h
rcu: Fix tracepoint tracking RCU CPU kthread utilization
rcu: Fix harmless omission of "CONFIG_" from #if condition
rcu: Avoid tick_dep_set_cpu() misordering
rcu: Provide wrappers for uses of ->rcu_read_lock_nesting
rcu: Use READ_ONCE() for ->expmask in rcu_read_unlock_special()
rcu: Clear ->rcu_read_unlock_special only once
rcu: Clear .exp_hint only when deferred quiescent state has been reported
rcu: Rename some instance of CONFIG_PREEMPTION to CONFIG_PREEMPT_RCU
rcu: Remove kfree_call_rcu_nobatch()
rcu: Remove kfree_rcu() special casing and lazy-callback handling
rcu: Add support for debug_objects debugging for kfree_rcu()
rcu: Add multiple in-flight batches of kfree_rcu() work
...
It was requested to remove the cond_func check but the follow up patch was
overlooked. Remove it now.
Fixes: 67719ef25e ("smp: Add a smp_cond_func_t argument to smp_call_function_many()")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200127083915.434tdkztorkklpdu@linutronix.de
There are several storage drivers like dm-multipath, iscsi, tcmu-runner,
amd nbd that have userspace components that can run in the IO path. For
example, iscsi and nbd's userspace deamons may need to recreate a socket
and/or send IO on it, and dm-multipath's daemon multipathd may need to
send SG IO or read/write IO to figure out the state of paths and re-set
them up.
In the kernel these drivers have access to GFP_NOIO/GFP_NOFS and the
memalloc_*_save/restore functions to control the allocation behavior,
but for userspace we would end up hitting an allocation that ended up
writing data back to the same device we are trying to allocate for.
The device is then in a state of deadlock, because to execute IO the
device needs to allocate memory, but to allocate memory the memory
layers want execute IO to the device.
Here is an example with nbd using a local userspace daemon that performs
network IO to a remote server. We are using XFS on top of the nbd device,
but it can happen with any FS or other modules layered on top of the nbd
device that can write out data to free memory. Here a nbd daemon helper
thread, msgr-worker-1, is performing a write/sendmsg on a socket to execute
a request. This kicks off a reclaim operation which results in a WRITE to
the nbd device and the nbd thread calling back into the mm layer.
[ 1626.609191] msgr-worker-1 D 0 1026 1 0x00004000
[ 1626.609193] Call Trace:
[ 1626.609195] ? __schedule+0x29b/0x630
[ 1626.609197] ? wait_for_completion+0xe0/0x170
[ 1626.609198] schedule+0x30/0xb0
[ 1626.609200] schedule_timeout+0x1f6/0x2f0
[ 1626.609202] ? blk_finish_plug+0x21/0x2e
[ 1626.609204] ? _xfs_buf_ioapply+0x2e6/0x410
[ 1626.609206] ? wait_for_completion+0xe0/0x170
[ 1626.609208] wait_for_completion+0x108/0x170
[ 1626.609210] ? wake_up_q+0x70/0x70
[ 1626.609212] ? __xfs_buf_submit+0x12e/0x250
[ 1626.609214] ? xfs_bwrite+0x25/0x60
[ 1626.609215] xfs_buf_iowait+0x22/0xf0
[ 1626.609218] __xfs_buf_submit+0x12e/0x250
[ 1626.609220] xfs_bwrite+0x25/0x60
[ 1626.609222] xfs_reclaim_inode+0x2e8/0x310
[ 1626.609224] xfs_reclaim_inodes_ag+0x1b6/0x300
[ 1626.609227] xfs_reclaim_inodes_nr+0x31/0x40
[ 1626.609228] super_cache_scan+0x152/0x1a0
[ 1626.609231] do_shrink_slab+0x12c/0x2d0
[ 1626.609233] shrink_slab+0x9c/0x2a0
[ 1626.609235] shrink_node+0xd7/0x470
[ 1626.609237] do_try_to_free_pages+0xbf/0x380
[ 1626.609240] try_to_free_pages+0xd9/0x1f0
[ 1626.609245] __alloc_pages_slowpath+0x3a4/0xd30
[ 1626.609251] ? ___slab_alloc+0x238/0x560
[ 1626.609254] __alloc_pages_nodemask+0x30c/0x350
[ 1626.609259] skb_page_frag_refill+0x97/0xd0
[ 1626.609274] sk_page_frag_refill+0x1d/0x80
[ 1626.609279] tcp_sendmsg_locked+0x2bb/0xdd0
[ 1626.609304] tcp_sendmsg+0x27/0x40
[ 1626.609307] sock_sendmsg+0x54/0x60
[ 1626.609308] ___sys_sendmsg+0x29f/0x320
[ 1626.609313] ? sock_poll+0x66/0xb0
[ 1626.609318] ? ep_item_poll.isra.15+0x40/0xc0
[ 1626.609320] ? ep_send_events_proc+0xe6/0x230
[ 1626.609322] ? hrtimer_try_to_cancel+0x54/0xf0
[ 1626.609324] ? ep_read_events_proc+0xc0/0xc0
[ 1626.609326] ? _raw_write_unlock_irq+0xa/0x20
[ 1626.609327] ? ep_scan_ready_list.constprop.19+0x218/0x230
[ 1626.609329] ? __hrtimer_init+0xb0/0xb0
[ 1626.609331] ? _raw_spin_unlock_irq+0xa/0x20
[ 1626.609334] ? ep_poll+0x26c/0x4a0
[ 1626.609337] ? tcp_tsq_write.part.54+0xa0/0xa0
[ 1626.609339] ? release_sock+0x43/0x90
[ 1626.609341] ? _raw_spin_unlock_bh+0xa/0x20
[ 1626.609342] __sys_sendmsg+0x47/0x80
[ 1626.609347] do_syscall_64+0x5f/0x1c0
[ 1626.609349] ? prepare_exit_to_usermode+0x75/0xa0
[ 1626.609351] entry_SYSCALL_64_after_hwframe+0x44/0xa9
This patch adds a new prctl command that daemons can use after they have
done their initial setup, and before they start to do allocations that
are in the IO path. It sets the PF_MEMALLOC_NOIO and PF_LESS_THROTTLE
flags so both userspace block and FS threads can use it to avoid the
allocation recursion and try to prevent from being throttled while
writing out data to free up memory.
Signed-off-by: Mike Christie <mchristi@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Tested-by: Masato Suzuki <masato.suzuki@wdc.com>
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Link: https://lore.kernel.org/r/20191112001900.9206-1-mchristi@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
- A mechanism to shield isolated tasks from managed interrupts:
The affinity of managed interrupts is completely controlled by the
kernel and user space has no influence on them. The reason is that
the automatically assigned affinity correlates to the multi-queue
CPU handling of block devices.
If the generated affinity mask spaws both housekeeping and isolated CPUs
the interrupt could be routed to an isolated CPU which would then be
disturbed by I/O submitted by a housekeeping CPU.
The new mechamism ensures that as long as one housekeeping CPU is online
in the assigned affinity mask the interrupt is routed to a housekeeping
CPU.
If there is no online housekeeping CPU in the affinity mask, then the
interrupt is routed to an isolated CPU to keep the device queue intact,
but unless the isolated CPU submits I/O by itself these interrupts are
not raised.
- A small addon to the device tree irqdomain core code to avoid
duplication in irq chip drivers
- Conversion of the SiFive PLIC to hierarchical domains
- The usual pile of new irq chip drivers: SiFive GPIO, Aspeed SCI, NXP
INTMUX, Meson A1 GPIO
- The first cut of support for the new ARM GICv4.1
- The usual pile of fixes and improvements in core and driver code
-----BEGIN PGP SIGNATURE-----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=E2VR
-----END PGP SIGNATURE-----
Merge tag 'irq-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"The interrupt departement provides:
- A mechanism to shield isolated tasks from managed interrupts:
The affinity of managed interrupts is completely controlled by the
kernel and user space has no influence on them. The reason is that
the automatically assigned affinity correlates to the multi-queue
CPU handling of block devices.
If the generated affinity mask spaws both housekeeping and isolated
CPUs the interrupt could be routed to an isolated CPU which would
then be disturbed by I/O submitted by a housekeeping CPU.
The new mechamism ensures that as long as one housekeeping CPU is
online in the assigned affinity mask the interrupt is routed to a
housekeeping CPU.
If there is no online housekeeping CPU in the affinity mask, then
the interrupt is routed to an isolated CPU to keep the device queue
intact, but unless the isolated CPU submits I/O by itself these
interrupts are not raised.
- A small addon to the device tree irqdomain core code to avoid
duplication in irq chip drivers
- Conversion of the SiFive PLIC to hierarchical domains
- The usual pile of new irq chip drivers: SiFive GPIO, Aspeed SCI,
NXP INTMUX, Meson A1 GPIO
- The first cut of support for the new ARM GICv4.1
- The usual pile of fixes and improvements in core and driver code"
* tag 'irq-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
genirq, sched/isolation: Isolate from handling managed interrupts
irqchip/gic-v4.1: Allow direct invalidation of VLPIs
irqchip/gic-v4.1: Suppress per-VLPI doorbell
irqchip/gic-v4.1: Add VPE INVALL callback
irqchip/gic-v4.1: Add VPE eviction callback
irqchip/gic-v4.1: Add VPE residency callback
irqchip/gic-v4.1: Add mask/unmask doorbell callbacks
irqchip/gic-v4.1: Plumb skeletal VPE irqchip
irqchip/gic-v4.1: Implement the v4.1 flavour of VMOVP
irqchip/gic-v4.1: Don't use the VPE proxy if RVPEID is set
irqchip/gic-v4.1: Implement the v4.1 flavour of VMAPP
irqchip/gic-v4.1: VPE table (aka GICR_VPROPBASER) allocation
irqchip/gic-v3: Add GICv4.1 VPEID size discovery
irqchip/gic-v3: Detect GICv4.1 supporting RVPEID
irqchip/gic-v3-its: Fix get_vlpi_map() breakage with doorbells
irqdomain: Fix a memory leak in irq_domain_push_irq()
irqchip: Add NXP INTMUX interrupt multiplexer support
dt-bindings: interrupt-controller: Add binding for NXP INTMUX interrupt multiplexer
irqchip: Define EXYNOS_IRQ_COMBINER
irqchip/meson-gpio: Add support for meson a1 SoCs
...
- Rework the smp function call core code to avoid the allocation of an
additional cpumask.
- Remove the not longer required GFP argument from on_each_cpu_cond() and
on_each_cpu_cond_mask() and fixup the callers.
-----BEGIN PGP SIGNATURE-----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=M4aK
-----END PGP SIGNATURE-----
Merge tag 'smp-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull core SMP updates from Thomas Gleixner:
"A small set of SMP core code changes:
- Rework the smp function call core code to avoid the allocation of
an additional cpumask
- Remove the not longer required GFP argument from on_each_cpu_cond()
and on_each_cpu_cond_mask() and fixup the callers"
* tag 'smp-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp: Remove allocation mask from on_each_cpu_cond.*()
smp: Add a smp_cond_func_t argument to smp_call_function_many()
smp: Use smp_cond_func_t as type for the conditional function
- Time namespace support:
If a container migrates from one host to another then it expects that
clocks based on MONOTONIC and BOOTTIME are not subject to
disruption. Due to different boot time and non-suspended runtime these
clocks can differ significantly on two hosts, in the worst case time
goes backwards which is a violation of the POSIX requirements.
The time namespace addresses this problem. It allows to set offsets for
clock MONOTONIC and BOOTTIME once after creation and before tasks are
associated with the namespace. These offsets are taken into account by
timers and timekeeping including the VDSO.
Offsets for wall clock based clocks (REALTIME/TAI) are not provided by
this mechanism. While in theory possible, the overhead and code
complexity would be immense and not justified by the esoteric potential
use cases which were discussed at Plumbers '18.
The overhead for tasks in the root namespace (host time offsets = 0) is
in the noise and great effort was made to ensure that especially in the
VDSO. If time namespace is disabled in the kernel configuration the
code is compiled out.
Kudos to Andrei Vagin and Dmitry Sofanov who implemented this feature
and kept on for more than a year addressing review comments, finding
better solutions. A pleasant experience.
- Overhaul of the alarmtimer device dependency handling to ensure that
the init/suspend/resume ordering is correct.
- A new clocksource/event driver for Microchip PIT64
- Suspend/resume support for the Hyper-V clocksource
- The usual pile of fixes, updates and improvements mostly in the
driver code.
-----BEGIN PGP SIGNATURE-----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=x3qT
-----END PGP SIGNATURE-----
Merge tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
"The timekeeping and timers departement provides:
- Time namespace support:
If a container migrates from one host to another then it expects
that clocks based on MONOTONIC and BOOTTIME are not subject to
disruption. Due to different boot time and non-suspended runtime
these clocks can differ significantly on two hosts, in the worst
case time goes backwards which is a violation of the POSIX
requirements.
The time namespace addresses this problem. It allows to set offsets
for clock MONOTONIC and BOOTTIME once after creation and before
tasks are associated with the namespace. These offsets are taken
into account by timers and timekeeping including the VDSO.
Offsets for wall clock based clocks (REALTIME/TAI) are not provided
by this mechanism. While in theory possible, the overhead and code
complexity would be immense and not justified by the esoteric
potential use cases which were discussed at Plumbers '18.
The overhead for tasks in the root namespace (ie where host time
offsets = 0) is in the noise and great effort was made to ensure
that especially in the VDSO. If time namespace is disabled in the
kernel configuration the code is compiled out.
Kudos to Andrei Vagin and Dmitry Sofanov who implemented this
feature and kept on for more than a year addressing review
comments, finding better solutions. A pleasant experience.
- Overhaul of the alarmtimer device dependency handling to ensure
that the init/suspend/resume ordering is correct.
- A new clocksource/event driver for Microchip PIT64
- Suspend/resume support for the Hyper-V clocksource
- The usual pile of fixes, updates and improvements mostly in the
driver code"
* tag 'timers-core-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
alarmtimer: Make alarmtimer_get_rtcdev() a stub when CONFIG_RTC_CLASS=n
alarmtimer: Use wakeup source from alarmtimer platform device
alarmtimer: Make alarmtimer platform device child of RTC device
alarmtimer: Update alarmtimer_get_rtcdev() docs to reflect reality
hrtimer: Add missing sparse annotation for __run_timer()
lib/vdso: Only read hrtimer_res when needed in __cvdso_clock_getres()
MIPS: vdso: Define BUILD_VDSO32 when building a 32bit kernel
clocksource/drivers/hyper-v: Set TSC clocksource as default w/ InvariantTSC
clocksource/drivers/hyper-v: Untangle stimers and timesync from clocksources
clocksource/drivers/timer-microchip-pit64b: Fix sparse warning
clocksource/drivers/exynos_mct: Rename Exynos to lowercase
clocksource/drivers/timer-ti-dm: Fix uninitialized pointer access
clocksource/drivers/timer-ti-dm: Switch to platform_get_irq
clocksource/drivers/timer-ti-dm: Convert to devm_platform_ioremap_resource
clocksource/drivers/em_sti: Fix variable declaration in em_sti_probe
clocksource/drivers/em_sti: Convert to devm_platform_ioremap_resource
clocksource/drivers/bcm2835_timer: Fix memory leak of timer
clocksource/drivers/cadence-ttc: Use ttc driver as platform driver
clocksource/drivers/timer-microchip-pit64b: Add Microchip PIT64B support
clocksource/drivers/hyper-v: Reserve PAGE_SIZE space for tsc page
...
- Enforce that the watchdog timestamp is always valid on boot. The
original implementation caused a watchdog disabled gap of one second in
the boot process due to truncation of the underlying sched clock. The
sched clock is divided by 1e9 to convert nanoseconds to seconds. So for
the first second of the boot process the result is 0 which is at the
same time the indicator to disable the watchdog. The trivial fix is to
change the disabled indicator to ULONG_MAX.
- Two cleanup patches removing unused and redundant code which got
forgotten to be cleaned up in previous changes.
-----BEGIN PGP SIGNATURE-----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=WMiM
-----END PGP SIGNATURE-----
Merge tag 'core-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull watchdog updates from Thomas Gleixner:
"A set of watchdog/softlockup related improvements:
- Enforce that the watchdog timestamp is always valid on boot. The
original implementation caused a watchdog disabled gap of one
second in the boot process due to truncation of the underlying
sched clock.
The sched clock is divided by 1e9 to convert nanoseconds to
seconds. So for the first second of the boot process the result is
0 which is at the same time the indicator to disable the watchdog.
The trivial fix is to change the disabled indicator to ULONG_MAX.
- Two cleanup patches removing unused and redundant code which got
forgotten to be cleaned up in previous changes"
* tag 'core-core-2020-01-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
watchdog/softlockup: Enforce that timestamp is valid on boot
watchdog/softlockup: Remove obsolete check of last reported task
watchdog: Remove soft_lockup_hrtimer_cnt and related code
- Make the update to the coarse timekeeper unconditional. This is required
because the coarse timekeeper interfaces in the VDSO do not depend on a
VDSO capable clocksource. If the system does not have a VDSO capable
clocksource and the update is depending on the VDSO capable clocksource,
the coarse VDSO interfaces would operate on stale data forever.
- Invert the logic of __arch_update_vdso_data() to avoid further head
scratching. Tripped over this several times while analyzing the update
problem above.
-----BEGIN PGP SIGNATURE-----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=ONO4
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"Two fixes for the generic VDSO code which missed 5.5:
- Make the update to the coarse timekeeper unconditional.
This is required because the coarse timekeeper interfaces in the
VDSO do not depend on a VDSO capable clocksource. If the system
does not have a VDSO capable clocksource and the update is
depending on the VDSO capable clocksource, the coarse VDSO
interfaces would operate on stale data forever.
- Invert the logic of __arch_update_vdso_data() to avoid further head
scratching.
Tripped over this several times while analyzing the update problem
above"
* tag 'timers-urgent-2020-01-27' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
lib/vdso: Update coarse timekeeper unconditionally
lib/vdso: Make __arch_update_vdso_data() logic understandable
-----BEGIN PGP SIGNATURE-----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=tPy4
-----END PGP SIGNATURE-----
Merge tag 'audit-pr-20200127' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit update from Paul Moore:
"One small audit patch for the Linux v5.6 merge window, and
unsurprisingly it passes our test suite with flying colors"
* tag 'audit-pr-20200127' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: Add __rcu annotation to RCU pointer
Pull cgroup updates from Tejun Heo:
- cgroup2 interface for hugetlb controller. I think this was the last
remaining bit which was missing from cgroup2
- fixes for race and a spurious warning in threaded cgroup handling
- other minor changes
* 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
iocost: Fix iocost_monitor.py due to helper type mismatch
cgroup: Prevent double killing of css when enabling threaded cgroup
cgroup: fix function name in comment
mm: hugetlb controller for cgroups v2
Pull workqueue updates from Tejun Heo:
"Just a couple tracepoint patches"
* 'for-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: remove workqueue_work event class
workqueue: add worker function to workqueue_execute_end tracepoint
- Update the ACPI processor driver in order to export
acpi_processor_evaluate_cst() to the code outside of it, add
ACPI support to the intel_idle driver based on that and clean
up that driver somewhat (Rafael Wysocki).
- Add an admin guide document for the intel_idle driver (Rafael
Wysocki).
- Clean up cpuidle core and drivers, enable compilation testing
for some of them (Benjamin Gaignard, Krzysztof Kozlowski, Rafael
Wysocki, Yangtao Li).
- Fix reference counting of OPP (operating performance points) table
structures (Viresh Kumar).
- Add support for CPR (Core Power Reduction) to the AVS (Adaptive
Voltage Scaling) subsystem (Niklas Cassel, Colin Ian King,
YueHaibing).
- Add support for TigerLake Mobile and JasperLake to the Intel RAPL
power capping driver (Zhang Rui).
- Update cpufreq drivers:
* Add i.MX8MP support to imx-cpufreq-dt (Anson Huang).
* Fix usage of a macro in loongson2_cpufreq (Alexandre Oliva).
* Fix cpufreq policy reference counting issues in s3c and
brcmstb-avs (chenqiwu).
* Fix ACPI table reference counting issue and HiSilicon quirk
handling in the CPPC driver (Hanjun Guo).
* Clean up spelling mistake in intel_pstate (Harry Pan).
* Convert the kirkwood and tegra186 drivers to using
devm_platform_ioremap_resource() (Yangtao Li).
- Update devfreq core:
* Add 'name' sysfs attribute for devfreq devices (Chanwoo Choi).
* Clean up the handing of transition statistics and allow them
to be reset by writing 0 to the 'trans_stat' devfreq device
attribute in sysfs (Kamil Konieczny).
* Add 'devfreq_summary' to debugfs (Chanwoo Choi).
* Clean up kerneldoc comments and Kconfig indentation (Krzysztof
Kozlowski, Randy Dunlap).
- Update devfreq drivers:
* Add dynamic scaling for the imx8m DDR controller and clean up
imx8m-ddrc (Leonard Crestez, YueHaibing).
* Fix DT node reference counting and nitialization error code path
in rk3399_dmc and add COMPILE_TEST and HAVE_ARM_SMCCC dependency
for it (Chanwoo Choi, Yangtao Li).
* Fix DT node reference counting in rockchip-dfi and make it use
devm_platform_ioremap_resource() (Yangtao Li).
* Fix excessive stack usage in exynos-ppmu (Arnd Bergmann).
* Fix initialization error code paths in exynos-bus (Yangtao Li).
* Clean up exynos-bus and exynos somewhat (Artur Świgoń, Krzysztof
Kozlowski).
- Add tracepoints for tracking usage_count updates unrelated to
status changes in PM-runtime (Michał Mirosław).
- Add sysfs attribute to control the "sync on suspend" behavior
during system-wide suspend (Jonas Meurer).
- Switch system-wide suspend tests over to 64-bit time (Alexandre
Belloni).
- Make wakeup sources statistics in debugfs cover deleted ones which
used to be the case some time ago (zhuguangqing).
- Clean up computations carried out during hibernation, update
messages related to hibernation and fix a spelling mistake in one
of them (Wen Yang, Luigi Semenzato, Colin Ian King).
- Add mailmap entry for maintainer e-mail address that has not been
functional for several years (Rafael Wysocki).
-----BEGIN PGP SIGNATURE-----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=g48u
-----END PGP SIGNATURE-----
Merge tag 'pm-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These add ACPI support to the intel_idle driver along with an admin
guide document for it, add support for CPR (Core Power Reduction) to
the AVS (Adaptive Voltage Scaling) subsystem, add new hardware support
in a few places, add some new sysfs attributes, debugfs files and
tracepoints, fix bugs and clean up a bunch of things all over.
Specifics:
- Update the ACPI processor driver in order to export
acpi_processor_evaluate_cst() to the code outside of it, add ACPI
support to the intel_idle driver based on that and clean up that
driver somewhat (Rafael Wysocki).
- Add an admin guide document for the intel_idle driver (Rafael
Wysocki).
- Clean up cpuidle core and drivers, enable compilation testing for
some of them (Benjamin Gaignard, Krzysztof Kozlowski, Rafael
Wysocki, Yangtao Li).
- Fix reference counting of OPP (operating performance points) table
structures (Viresh Kumar).
- Add support for CPR (Core Power Reduction) to the AVS (Adaptive
Voltage Scaling) subsystem (Niklas Cassel, Colin Ian King,
YueHaibing).
- Add support for TigerLake Mobile and JasperLake to the Intel RAPL
power capping driver (Zhang Rui).
- Update cpufreq drivers:
- Add i.MX8MP support to imx-cpufreq-dt (Anson Huang).
- Fix usage of a macro in loongson2_cpufreq (Alexandre Oliva).
- Fix cpufreq policy reference counting issues in s3c and
brcmstb-avs (chenqiwu).
- Fix ACPI table reference counting issue and HiSilicon quirk
handling in the CPPC driver (Hanjun Guo).
- Clean up spelling mistake in intel_pstate (Harry Pan).
- Convert the kirkwood and tegra186 drivers to using
devm_platform_ioremap_resource() (Yangtao Li).
- Update devfreq core:
- Add 'name' sysfs attribute for devfreq devices (Chanwoo Choi).
- Clean up the handing of transition statistics and allow them to
be reset by writing 0 to the 'trans_stat' devfreq device
attribute in sysfs (Kamil Konieczny).
- Add 'devfreq_summary' to debugfs (Chanwoo Choi).
- Clean up kerneldoc comments and Kconfig indentation (Krzysztof
Kozlowski, Randy Dunlap).
- Update devfreq drivers:
- Add dynamic scaling for the imx8m DDR controller and clean up
imx8m-ddrc (Leonard Crestez, YueHaibing).
- Fix DT node reference counting and nitialization error code path
in rk3399_dmc and add COMPILE_TEST and HAVE_ARM_SMCCC dependency
for it (Chanwoo Choi, Yangtao Li).
- Fix DT node reference counting in rockchip-dfi and make it use
devm_platform_ioremap_resource() (Yangtao Li).
- Fix excessive stack usage in exynos-ppmu (Arnd Bergmann).
- Fix initialization error code paths in exynos-bus (Yangtao Li).
- Clean up exynos-bus and exynos somewhat (Artur Świgoń, Krzysztof
Kozlowski).
- Add tracepoints for tracking usage_count updates unrelated to
status changes in PM-runtime (Michał Mirosław).
- Add sysfs attribute to control the "sync on suspend" behavior
during system-wide suspend (Jonas Meurer).
- Switch system-wide suspend tests over to 64-bit time (Alexandre
Belloni).
- Make wakeup sources statistics in debugfs cover deleted ones which
used to be the case some time ago (zhuguangqing).
- Clean up computations carried out during hibernation, update
messages related to hibernation and fix a spelling mistake in one
of them (Wen Yang, Luigi Semenzato, Colin Ian King).
- Add mailmap entry for maintainer e-mail address that has not been
functional for several years (Rafael Wysocki)"
* tag 'pm-5.6-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (83 commits)
cpufreq: loongson2_cpufreq: adjust cpufreq uses of LOONGSON_CHIPCFG
intel_idle: Clean up irtl_2_usec()
intel_idle: Move 3 functions closer to their callers
intel_idle: Annotate initialization code and data structures
intel_idle: Move and clean up intel_idle_cpuidle_devices_uninit()
intel_idle: Rearrange intel_idle_cpuidle_driver_init()
intel_idle: Clean up NULL pointer check in intel_idle_init()
intel_idle: Fold intel_idle_probe() into intel_idle_init()
intel_idle: Eliminate __setup_broadcast_timer()
cpuidle: fix cpuidle_find_deepest_state() kerneldoc warnings
cpuidle: sysfs: fix warnings when compiling with W=1
cpuidle: coupled: fix warnings when compiling with W=1
cpufreq: brcmstb-avs: fix imbalance of cpufreq policy refcount
PM: suspend: Add sysfs attribute to control the "sync on suspend" behavior
PM / devfreq: Add debugfs support with devfreq_summary file
Documentation: admin-guide: PM: Add intel_idle document
cpuidle: arm: Enable compile testing for some of drivers
PM-runtime: add tracepoints for usage_count changes
cpufreq: intel_pstate: fix spelling mistake: "Whethet" -> "Whether"
PM: hibernate: fix spelling mistake "shapshot" -> "snapshot"
...
- New architecture features
* Support for Armv8.5 E0PD, which benefits KASLR in the same way as
KPTI but without the overhead. This allows KPTI to be disabled on
CPUs that are not affected by Meltdown, even is KASLR is enabled.
* Initial support for the Armv8.5 RNG instructions, which claim to
provide access to a high bandwidth, cryptographically secure hardware
random number generator. As well as exposing these to userspace, we
also use them as part of the KASLR seed and to seed the crng once
all CPUs have come online.
* Advertise a bunch of new instructions to userspace, including support
for Data Gathering Hint, Matrix Multiply and 16-bit floating point.
- Kexec
* Cleanups in preparation for relocating with the MMU enabled
* Support for loading crash dump kernels with kexec_file_load()
- Perf and PMU drivers
* Cleanups and non-critical fixes for a couple of system PMU drivers
- FPU-less (aka broken) CPU support
* Considerable fixes to support CPUs without the FP/SIMD extensions,
including their presence in heterogeneous systems. Good luck finding
a 64-bit userspace that handles this.
- Modern assembly function annotations
* Start migrating our use of ENTRY() and ENDPROC() over to the
new-fangled SYM_{CODE,FUNC}_{START,END} macros, which are intended to
aid debuggers
- Kbuild
* Cleanup detection of LSE support in the assembler by introducing
'as-instr'
* Remove compressed Image files when building clean targets
- IP checksumming
* Implement optimised IPv4 checksumming routine when hardware offload
is not in use. An IPv6 version is in the works, pending testing.
- Hardware errata
* Work around Cortex-A55 erratum #1530923
- Shadow call stack
* Work around some issues with Clang's integrated assembler not liking
our perfectly reasonable assembly code
* Avoid allocating the X18 register, so that it can be used to hold the
shadow call stack pointer in future
- ACPI
* Fix ID count checking in IORT code. This may regress broken firmware
that happened to work with the old implementation, in which case we'll
have to revert it and try something else
* Fix DAIF corruption on return from GHES handler with pseudo-NMIs
- Miscellaneous
* Whitelist some CPUs that are unaffected by Spectre-v2
* Reduce frequency of ASID rollover when KPTI is compiled in but
inactive
* Reserve a couple of arch-specific PROT flags that are already used by
Sparc and PowerPC and are planned for later use with BTI on arm64
* Preparatory cleanup of our entry assembly code in preparation for
moving more of it into C later on
* Refactoring and cleanup
-----BEGIN PGP SIGNATURE-----
iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl4oY+IQHHdpbGxAa2Vy
bmVsLm9yZwAKCRC3rHDchMFjNNfRB/4p3vax0hqaOnLRvmJPRXF31B8oPlivnr2u
6HCA9LkdU5IlrgaTNOJ/sQEqJAPOPCU7v49Ol0iYw0iKL1suUE7Ikui5VB6Uybqt
YbfF5UNzfXAMs2A86TF/hzqhxw+W+lpnZX8NVTuQeAODfHEGUB1HhTLfRi9INsER
wKEAuoZyuSUibxTFvji+DAq7nVRniXX7CM7tE385pxDisCMuu/7E5wOl+3EZYXWz
DTGzTbHXuVFL+UFCANFEUlAtmr3dQvPFIqAwVl/CxjRJjJ7a+/G3cYLsHFPrQCjj
qYX4kfhAeeBtqmHL7YFNWFwFs5WaT5UcQquFO665/+uCTWSJpORY
=AIh/
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"The changes are a real mixed bag this time around.
The only scary looking one from the diffstat is the uapi change to
asm-generic/mman-common.h, but this has been acked by Arnd and is
actually just adding a pair of comments in an attempt to prevent
allocation of some PROT values which tend to get used for
arch-specific purposes. We'll be using them for Branch Target
Identification (a CFI-like hardening feature), which is currently
under review on the mailing list.
New architecture features:
- Support for Armv8.5 E0PD, which benefits KASLR in the same way as
KPTI but without the overhead. This allows KPTI to be disabled on
CPUs that are not affected by Meltdown, even is KASLR is enabled.
- Initial support for the Armv8.5 RNG instructions, which claim to
provide access to a high bandwidth, cryptographically secure
hardware random number generator. As well as exposing these to
userspace, we also use them as part of the KASLR seed and to seed
the crng once all CPUs have come online.
- Advertise a bunch of new instructions to userspace, including
support for Data Gathering Hint, Matrix Multiply and 16-bit
floating point.
Kexec:
- Cleanups in preparation for relocating with the MMU enabled
- Support for loading crash dump kernels with kexec_file_load()
Perf and PMU drivers:
- Cleanups and non-critical fixes for a couple of system PMU drivers
FPU-less (aka broken) CPU support:
- Considerable fixes to support CPUs without the FP/SIMD extensions,
including their presence in heterogeneous systems. Good luck
finding a 64-bit userspace that handles this.
Modern assembly function annotations:
- Start migrating our use of ENTRY() and ENDPROC() over to the
new-fangled SYM_{CODE,FUNC}_{START,END} macros, which are intended
to aid debuggers
Kbuild:
- Cleanup detection of LSE support in the assembler by introducing
'as-instr'
- Remove compressed Image files when building clean targets
IP checksumming:
- Implement optimised IPv4 checksumming routine when hardware offload
is not in use. An IPv6 version is in the works, pending testing.
Hardware errata:
- Work around Cortex-A55 erratum #1530923
Shadow call stack:
- Work around some issues with Clang's integrated assembler not
liking our perfectly reasonable assembly code
- Avoid allocating the X18 register, so that it can be used to hold
the shadow call stack pointer in future
ACPI:
- Fix ID count checking in IORT code. This may regress broken
firmware that happened to work with the old implementation, in
which case we'll have to revert it and try something else
- Fix DAIF corruption on return from GHES handler with pseudo-NMIs
Miscellaneous:
- Whitelist some CPUs that are unaffected by Spectre-v2
- Reduce frequency of ASID rollover when KPTI is compiled in but
inactive
- Reserve a couple of arch-specific PROT flags that are already used
by Sparc and PowerPC and are planned for later use with BTI on
arm64
- Preparatory cleanup of our entry assembly code in preparation for
moving more of it into C later on
- Refactoring and cleanup"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (73 commits)
arm64: acpi: fix DAIF manipulation with pNMI
arm64: kconfig: Fix alignment of E0PD help text
arm64: Use v8.5-RNG entropy for KASLR seed
arm64: Implement archrandom.h for ARMv8.5-RNG
arm64: kbuild: remove compressed images on 'make ARCH=arm64 (dist)clean'
arm64: entry: Avoid empty alternatives entries
arm64: Kconfig: select HAVE_FUTEX_CMPXCHG
arm64: csum: Fix pathological zero-length calls
arm64: entry: cleanup sp_el0 manipulation
arm64: entry: cleanup el0 svc handler naming
arm64: entry: mark all entry code as notrace
arm64: assembler: remove smp_dmb macro
arm64: assembler: remove inherit_daif macro
ACPI/IORT: Fix 'Number of IDs' handling in iort_id_map()
mm: Reserve asm-generic prot flags 0x10 and 0x20 for arch use
arm64: Use macros instead of hard-coded constants for MAIR_EL1
arm64: Add KRYO{3,4}XX CPU cores to spectre-v2 safe list
arm64: kernel: avoid x18 in __cpu_soft_restart
arm64: kvm: stop treating register x18 as caller save
arm64/lib: copy_page: avoid x18 register in assembler code
...
Thomas Richter reported:
> Test case 66 'Use vfs_getname probe to get syscall args filenames'
> is broken on s390, but works on x86. The test case fails with:
>
> [root@m35lp76 perf]# perf test -F 66
> 66: Use vfs_getname probe to get syscall args filenames
> :Recording open file:
> [ perf record: Woken up 1 times to write data ]
> [ perf record: Captured and wrote 0.004 MB /tmp/__perf_test.perf.data.TCdYj\
> (20 samples) ]
> Looking at perf.data file for vfs_getname records for the file we touched:
> FAILED!
> [root@m35lp76 perf]#
The root cause was the print_fmt of the kprobe event that referenced the
"ustring"
> Setting up the kprobe event using perf command:
>
> # ./perf probe "vfs_getname=getname_flags:72 pathname=filename:ustring"
>
> generates this format file:
> [root@m35lp76 perf]# cat /sys/kernel/debug/tracing/events/probe/\
> vfs_getname/format
> name: vfs_getname
> ID: 1172
> format:
> field:unsigned short common_type; offset:0; size:2; signed:0;
> field:unsigned char common_flags; offset:2; size:1; signed:0;
> field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
> field:int common_pid; offset:4; size:4; signed:1;
>
> field:unsigned long __probe_ip; offset:8; size:8; signed:0;
> field:__data_loc char[] pathname; offset:16; size:4; signed:1;
>
> print fmt: "(%lx) pathname=\"%s\"", REC->__probe_ip, REC->pathname
Instead of using "__get_str(pathname)" it referenced it directly.
Link: http://lkml.kernel.org/r/20200124100742.4050c15e@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 88903c4643 ("tracing/probe: Add ustring type for user-space string")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-01-27
The following pull-request contains BPF updates for your *net-next* tree.
We've added 20 non-merge commits during the last 5 day(s) which contain
a total of 24 files changed, 433 insertions(+), 104 deletions(-).
The main changes are:
1) Make BPF trampolines and dispatcher aware for the stack unwinder, from Jiri Olsa.
2) Improve handling of failed CO-RE relocations in libbpf, from Andrii Nakryiko.
3) Several fixes to BPF sockmap and reuseport selftests, from Lorenz Bauer.
4) Various cleanups in BPF devmap's XDP flush code, from John Fastabend.
5) Fix BPF flow dissector when used with port ranges, from Yoshiki Komachi.
6) Fix bpffs' map_seq_next callback to always inc position index, from Vasily Averin.
7) Allow overriding LLVM tooling for runqslower utility, from Andrey Ignatov.
8) Silence false-positive lockdep splats in devmap hash lookup, from Amol Grover.
9) Fix fentry/fexit selftests to initialize a variable before use, from John Sperbeck.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
* pm-cpufreq:
cpufreq: loongson2_cpufreq: adjust cpufreq uses of LOONGSON_CHIPCFG
cpufreq: brcmstb-avs: fix imbalance of cpufreq policy refcount
cpufreq: intel_pstate: fix spelling mistake: "Whethet" -> "Whether"
cpufreq: s3c: fix unbalances of cpufreq policy refcount
cpufreq: imx-cpufreq-dt: Add i.MX8MP support
cpufreq: Use imx-cpufreq-dt for i.MX8MP's speed grading
cpufreq: tegra186: convert to devm_platform_ioremap_resource
cpufreq: kirkwood: convert to devm_platform_ioremap_resource
cpufreq: CPPC: put ACPI table after using it
cpufreq : CPPC: Break out if HiSilicon CPPC workaround is matched
* pm-sleep:
PM: suspend: Add sysfs attribute to control the "sync on suspend" behavior
PM: hibernate: fix spelling mistake "shapshot" -> "snapshot"
PM: hibernate: Add more logging on hibernation failure
PM: hibernate: improve arithmetic division in preallocate_highmem_fraction()
PM: wakeup: Show statistics for deleted wakeup sources again
PM: sleep: Switch to rtc_time64_to_tm()/rtc_tm_to_time64()
Now that we depend on rcu_call() and synchronize_rcu() to also wait
for preempt_disabled region to complete the rcu read critical section
in __dev_map_flush() is no longer required. Except in a few special
cases in drivers that need it for other reasons.
These originally ensured the map reference was safe while a map was
also being free'd. And additionally that bpf program updates via
ndo_bpf did not happen while flush updates were in flight. But flush
by new rules can only be called from preempt-disabled NAPI context.
The synchronize_rcu from the map free path and the rcu_call from the
delete path will ensure the reference there is safe. So lets remove
the rcu_read_lock and rcu_read_unlock pair to avoid any confusion
around how this is being protected.
If the rcu_read_lock was required it would mean errors in the above
logic and the original patch would also be wrong.
Now that we have done above we put the rcu_read_lock in the driver
code where it is needed in a driver dependent way. I think this
helps readability of the code so we know where and why we are
taking read locks. Most drivers will not need rcu_read_locks here
and further XDP drivers already have rcu_read_locks in their code
paths for reading xdp programs on RX side so this makes it symmetric
where we don't have half of rcu critical sections define in driver
and the other half in devmap.
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/1580084042-11598-4-git-send-email-john.fastabend@gmail.com
Now that we rely on synchronize_rcu and call_rcu waiting to
exit perempt-disable regions (NAPI) lets update the comments
to reflect this.
Fixes: 0536b85239 ("xdp: Simplify devmap cleanup")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/1580084042-11598-2-git-send-email-john.fastabend@gmail.com
This patch fixes the following sparse errors by annotating the
sighand_struct with __rcu
kernel/fork.c:1511:9: error: incompatible types in comparison expression
kernel/exit.c💯19: error: incompatible types in comparison expression
kernel/signal.c:1370:27: error: incompatible types in comparison expression
This fix introduces the following sparse error in signal.c due to
checking the sighand pointer without rcu primitives:
kernel/signal.c:1386:21: error: incompatible types in comparison expression
This new sparse error is also fixed in this patch.
Signed-off-by: Madhuparna Bhowmik <madhuparnabhowmik10@gmail.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/r/20200124045908.26389-1-madhuparnabhowmik10@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Boot-time processing often loops in the kernel longer than one might
prefer, which can prevent expedited grace periods from completing in
a timely manner. This in turn triggers a splat In nohz_full CPUs One
could argue that long-looping code should be fixed, but on the other hand,
boot time is a bit special.
This commit therefore removes the splat. Later commits will add the
splat back in, but in a way that removes false positives.
Reported-by: Borislav Petkov <bp@alien8.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
As warnings can trigger panics, especially when "panic_on_warn" is set,
memory failure warnings can cause panics and fail fuzz testers that are
stressing memory.
Create a MEM_FAIL() macro to use instead of WARN() in the tracing code
(perhaps this should be a kernel wide macro?), and use that for memory
failure issues. This should stop failing fuzz tests due to warnings.
Link: https://lore.kernel.org/r/CACT4Y+ZP-7np20GVRu3p+eZys9GPtbu+JpfV+HtsufAzvTgJrg@mail.gmail.com
Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When unwinding the stack we need to identify each address
to successfully continue. Adding latch tree to keep trampolines
for quick lookup during the unwind.
The patch uses first 48 bytes for latch tree node, leaving 4048
bytes from the rest of the page for trampoline or dispatcher
generated code.
It's still enough not to affect trampoline and dispatcher progs
maximum counts.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200123161508.915203-3-jolsa@kernel.org
When accessing the context we allow access to arguments with
scalar type and pointer to struct. But we deny access for
pointer to scalar type, which is the case for many functions.
Alexei suggested to take conservative approach and allow
currently only string pointer access, which is the case
for most functions now:
Adding check if the pointer is to string type and allow access to it.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200123161508.915203-2-jolsa@kernel.org
The trace_array_get_by_name() creates a ftrace instance and
trace_array_put() is used to remove the reference. Even though the
trace_array_get_by_name() creates the instance, it also adds a reference
count to it, that prevents user space from removing it.
As the bootconfig just creates the instance on boot up, it should still be
used where it can be deleted by user space after boot. A trace_array_put()
is required to let that happen.
Also, change the documentation on trace_array_get_by_name() to make this not
be so confusing.
Link: https://lore.kernel.org/r/20200124205927.76128804@rorschach.local.home
Fixes: 4f712a4d04 ("tracing/boot: Add instance node support")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We checked "iter->trace" earlier so there is no need to check here.
Link: http://lkml.kernel.org/r/20141122183012.GB6994@mwanda
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
[ Pulled from the archeological digging of my INBOX ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
I noticed when trying to use the trace-cmd python interface that reading the raw
buffer wasn't working for kernel_stack events. This is because it uses a
stubbed version of __dynamic_array that doesn't do the __data_loc trick and
encode the length of the array into the field. Instead it just shows up as a
size of 0. So change this to __array and set the len to FTRACE_STACK_ENTRIES
since this is what we actually do in practice and matches how user_stack_trace
works.
Link: http://lkml.kernel.org/r/1411589652-1318-1-git-send-email-jbacik@fb.com
Signed-off-by: Josef Bacik <jbacik@fb.com>
[ Pulled from the archeological digging of my INBOX ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
tracing_stat_init() was always returning '0', even on the error paths. It
now returns -ENODEV if tracing_init_dentry() fails or -ENOMEM if it fails
to created the 'trace_stat' debugfs directory.
Link: http://lkml.kernel.org/r/1410299381-20108-1-git-send-email-luis.henriques@canonical.com
Fixes: ed6f1c996b ("tracing: Check return value of tracing_init_dentry()")
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>
[ Pulled from the archeological digging of my INBOX ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Looking through old emails in my INBOX, I came across a patch from Luis
Henriques that attempted to fix a race of two stat tracers registering the
same stat trace (extremely unlikely, as this is done in the kernel, and
probably doesn't even exist). The submitted patch wasn't quite right as it
needed to deal with clean up a bit better (if two stat tracers were the
same, it would have the same files).
But to make the code cleaner, all we needed to do is to keep the
all_stat_sessions_mutex held for most of the registering function.
Link: http://lkml.kernel.org/r/1410299375-20068-1-git-send-email-luis.henriques@canonical.com
Fixes: 002bb86d8d ("tracing/ftrace: separate events tracing and stats tracing engine")
Reported-by: Luis Henriques <luis.henriques@canonical.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The stubbed version of alarmtimer_get_rtcdev() is not exported.
so this won't work if this function is used in a module when
CONFIG_RTC_CLASS=n.
Move the stub function to the header file and make it inline so that
callers don't have to worry about linking against this symbol.
rtcdev isn't used outside of this ifdef so it's not required to be
redefined to NULL. Drop that while touching this area.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200124055849.154411-4-swboyd@chromium.org
Use the wakeup source that can be associated with the 'alarmtimer'
platform device instead of registering another one by hand.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200124055849.154411-3-swboyd@chromium.org
The alarmtimer_suspend() function will fail if an RTC device is on a bus
such as SPI or i2c and that RTC device registers and probes after
alarmtimer_init() registers and probes the 'alarmtimer' platform device.
This is because system wide suspend suspends devices in the reverse order
of their probe. When alarmtimer_suspend() attempts to program the RTC for a
wakeup it will try to program an RTC device on a bus that has already been
suspended.
Move the alarmtimer device registration to happen when the RTC which is
used for wakeup is registered. Register the 'alarmtimer' platform device as
a child of the RTC device too, so that it can be guaranteed that the RTC
device won't be suspended when alarmtimer_suspend() is called.
Reported-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20200124055849.154411-2-swboyd@chromium.org
This function doesn't do anything like this comment says when an RTC device
hasn't been chosen. It looks like we used to do something like that before
commit 8bc0dafb5c ("alarmtimers: Rework RTC device selection using class
interface") but that's long gone now. Remove this sentence to avoid
confusing the reader.
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200124055849.154411-5-swboyd@chromium.org
The allocation mask is no longer used by on_each_cpu_cond() and
on_each_cpu_cond_mask() and can be removed.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200117090137.1205765-4-bigeasy@linutronix.de
on_each_cpu_cond_mask() allocates a new CPU mask. The newly allocated
mask is a subset of the provided mask based on the conditional function.
This memory allocation can be avoided by extending smp_call_function_many()
with the conditional function and performing the remote function call based
on the mask and the conditional function.
Rename smp_call_function_many() to smp_call_function_many_cond() and add
the smp_cond_func_t argument. If smp_cond_func_t is provided then it is
used before invoking the function. Provide smp_call_function_many() with
cond_func set to NULL. Let on_each_cpu_cond_mask() use
smp_call_function_many_cond().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200117090137.1205765-3-bigeasy@linutronix.de
Use a typdef for the conditional function instead defining it each time in
the function prototype.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200117090137.1205765-2-bigeasy@linutronix.de
- Conversion of the SiFive PLIC to hierarchical domains
- New SiFive GPIO irqchip driver
- New Aspeed SCI irqchip driver
- New NXP INTMUX irqchip driver
- Additional support for the Meson A1 GPIO irqchip
- First part of the GICv4.1 support
- Assorted fixes
-----BEGIN PGP SIGNATURE-----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=8iz1
-----END PGP SIGNATURE-----
Merge tag 'irqchip-5.6' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier:
- Conversion of the SiFive PLIC to hierarchical domains
- New SiFive GPIO irqchip driver
- New Aspeed SCI irqchip driver
- New NXP INTMUX irqchip driver
- Additional support for the Meson A1 GPIO irqchip
- First part of the GICv4.1 support
- Assorted fixes
Long ago, RCU used the stop-machine mechanism to implement expedited
grace periods, but no longer does so. This commit therefore removes
the no-longer-needed #includes of linux/stop_machine.h.
Link: https://lwn.net/Articles/805317/
Reported-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The ->srcu_last_gp_end field is accessed from any CPU at any time
by synchronize_srcu(), so non-initialization references need to use
READ_ONCE() and WRITE_ONCE(). This commit therefore makes that change.
Reported-by: syzbot+08f3e9d26e5541e1ecf2@syzkaller.appspotmail.com
Acked-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, force_qs_rnp() uses a for_each_leaf_node_possible_cpu()
loop containing a check of the current CPU's bit in ->qsmask.
This works, but this commit saves three lines by instead using
for_each_leaf_node_cpu_mask(), which combines the functionality of
for_each_leaf_node_possible_cpu() and leaf_node_cpu_bit(). This commit
also replaces the use of the local variable "bit" with rdp->grpmask.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit moves the rcu_{expedited,normal} definitions from
kernel/rcu/update.c to include/linux/rcupdate.h to make sure they are
in sync, and also to avoid the following warning from sparse:
kernel/ksysfs.c:150:5: warning: symbol 'rcu_expedited' was not declared. Should it be static?
kernel/ksysfs.c:167:5: warning: symbol 'rcu_normal' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Only tree_stall.h needs to get name from GP state, so this commit
moves the gp_state_names[] array and the gp_state_getname()
from kernel/rcu/tree.h and kernel/rcu/tree.c, respectively, to
kernel/rcu/tree_stall.h. While moving gp_state_names[], this commit
uses the GCC syntax to ensure that the right string is associated with
the right CPP macro.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The call_rcu() function is an external RCU API that is declared in
include/linux/rcupdate.h. There is thus no point in redeclaring it
in kernel/rcu/tree.h, so this commit removes that redundant declaration.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In the call to trace_rcu_utilization() at the start of the loop in
rcu_cpu_kthread(), "rcu_wait" is incorrect, plus this trace event needs
to be hoisted above the loop to balance with either the "rcu_wait" or
"rcu_yield", depending on how the loop exits. This commit therefore
makes these changes.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The C preprocessor macros SRCU and TINY_RCU should instead be CONFIG_SRCU
and CONFIG_TINY_RCU, respectively in the #f in kernel/rcu/rcu.h. But
there is no harm when "TINY_RCU" is wrongly used, which are always
non-defined, which makes "!defined(TINY_RCU)" always true, which means
the code block is always included, and the included code block doesn't
cause any compilation error so far in CONFIG_TINY_RCU builds. It is
also the reason this change should not be taken in -stable.
This commit adds the needed "CONFIG_" prefix to both macros.
Not for -stable.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In the current code, rcu_nmi_enter_common() might decide to turn on
the tick using tick_dep_set_cpu(), but be delayed just before doing so.
Then the grace-period kthread might notice that the CPU in question had
in fact gone through a quiescent state, thus turning off the tick using
tick_dep_clear_cpu(). The later invocation of tick_dep_set_cpu() would
then incorrectly leave the tick on.
This commit therefore enlists the aid of the leaf rcu_node structure's
->lock to ensure that decisions to enable or disable the tick are
carried out before they can be reversed.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit provides wrapper functions for uses of ->rcu_read_lock_nesting
to improve readability and to ease future changes to support inlining
of __rcu_read_lock() and __rcu_read_unlock().
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_node structure's ->expmask field is updated only when holding the
->lock, but is also accessed locklessly. This means that all ->expmask
updates must use WRITE_ONCE() and all reads carried out without holding
->lock must use READ_ONCE(). This commit therefore changes the lockless
->expmask read in rcu_read_unlock_special() to use READ_ONCE().
Reported-by: syzbot+99f4ddade3c22ab0cf23@syzkaller.appspotmail.com
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Marco Elver <elver@google.com>
In rcu_preempt_deferred_qs_irqrestore(), ->rcu_read_unlock_special is
cleared one piece at a time. Given that the "if" statements in this
function use the copy in "special", this commit removes the clearing
of the individual pieces in favor of clearing ->rcu_read_unlock_special
in one go just after it has been determined to be non-zero.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, the .exp_hint flag is cleared in rcu_read_unlock_special(),
which works, but which can also prevent subsequent rcu_read_unlock() calls
from helping expedite the quiescent state needed by an ongoing expedited
RCU grace period. This commit therefore defers clearing of .exp_hint
from rcu_read_unlock_special() to rcu_preempt_deferred_qs_irqrestore(),
thus ensuring that intervening calls to rcu_read_unlock() have a chance
to help end the expedited grace period.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
CONFIG_PREEMPTION and CONFIG_PREEMPT_RCU are always identical,
but some code depends on CONFIG_PREEMPTION to access to
rcu_preempt functionality. This patch changes CONFIG_PREEMPTION
to CONFIG_PREEMPT_RCU in these cases.
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that the kfree_rcu() special-casing has been removed from tree RCU,
this commit removes kfree_call_rcu_nobatch() since it is no longer needed.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit removes kfree_rcu() special-casing and the lazy-callback
handling from Tree RCU. It moves some of this special casing to Tiny RCU,
the removal of which will be the subject of later commits.
This results in a nice negative delta.
Suggested-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Add slab.h #include, thanks to kbuild test robot <lkp@intel.com>. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit applies RCU's debug_objects debugging to the new batched
kfree_rcu() implementations. The object is queued at the kfree_rcu()
call and dequeued during reclaim.
Tested that enabling CONFIG_DEBUG_OBJECTS_RCU_HEAD successfully detects
double kfree_rcu() calls.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Fix IRQ per kbuild test robot <lkp@intel.com> feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
During testing, it was observed that amount of memory consumed due
kfree_rcu() batching is 300-400MB. Previously we had only a single
head_free pointer pointing to the list of rcu_head(s) that are to be
freed after a grace period. Until this list is drained, we cannot queue
any more objects on it since such objects may not be ready to be
reclaimed when the worker thread eventually gets to drainin g the
head_free list.
We can do better by maintaining multiple lists as done by this patch.
Testing shows that memory consumption came down by around 100-150MB with
just adding another list. Adding more than 1 additional list did not
show any improvement.
Suggested-by: Paul E. McKenney <paulmck@linux.ibm.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Code style and initialization handling. ]
[ paulmck: Fix field name, reported by kbuild test robot <lkp@intel.com>. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Because the ->monitor_todo field is always protected by krcp->lock,
this commit downgrades from xchg() to non-atomic unmarked assignment
statements.
Signed-off-by: Joel Fernandes <joel@joelfernandes.org>
[ paulmck: Update to include early-boot kick code. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This test runs kfree_rcu() in a loop to measure performance of the new
kfree_rcu() batching functionality.
The following table shows results when booting with arguments:
rcuperf.kfree_loops=20000 rcuperf.kfree_alloc_num=8000
rcuperf.kfree_rcu_test=1 rcuperf.kfree_no_batch=X
rcuperf.kfree_no_batch=X # Grace Periods Test Duration (s)
X=1 (old behavior) 9133 11.5
X=0 (new behavior) 1732 12.5
On a 16 CPU system with the above boot parameters, we see that the total
number of grace periods that elapse during the test drops from 9133 when
not batching to 1732 when batching (a 5X improvement). The kfree_rcu()
flood itself slows down a bit when batching, though, as shown.
Note that the active memory consumption during the kfree_rcu() flood
does increase to around 200-250MB due to the batching (from around 50MB
without batching). However, this memory consumption is relatively
constant. In other words, the system is able to keep up with the
kfree_rcu() load. The memory consumption comes down considerably if
KFREE_DRAIN_JIFFIES is increased from HZ/50 to HZ/80. A later patch will
reduce memory consumption further by using multiple lists.
Also, when running the test, please disable CONFIG_DEBUG_PREEMPT and
CONFIG_PROVE_RCU for realistic comparisons with/without batching.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Recently a discussion about stability and performance of a system
involving a high rate of kfree_rcu() calls surfaced on the list [1]
which led to another discussion how to prepare for this situation.
This patch adds basic batching support for kfree_rcu(). It is "basic"
because we do none of the slab management, dynamic allocation, code
moving or any of the other things, some of which previous attempts did
[2]. These fancier improvements can be follow-up patches and there are
different ideas being discussed in those regards. This is an effort to
start simple, and build up from there. In the future, an extension to
use kfree_bulk and possibly per-slab batching could be done to further
improve performance due to cache-locality and slab-specific bulk free
optimizations. By using an array of pointers, the worker thread
processing the work would need to read lesser data since it does not
need to deal with large rcu_head(s) any longer.
Torture tests follow in the next patch and show improvements of around
5x reduction in number of grace periods on a 16 CPU system. More
details and test data are in that patch.
There is an implication with rcu_barrier() with this patch. Since the
kfree_rcu() calls can be batched, and may not be handed yet to the RCU
machinery in fact, the monitor may not have even run yet to do the
queue_rcu_work(), there seems no easy way of implementing rcu_barrier()
to wait for those kfree_rcu()s that are already made. So this means a
kfree_rcu() followed by an rcu_barrier() does not imply that memory will
be freed once rcu_barrier() returns.
Another implication is higher active memory usage (although not
run-away..) until the kfree_rcu() flooding ends, in comparison to
without batching. More details about this are in the second patch which
adds an rcuperf test.
Finally, in the near future we will get rid of kfree_rcu() special casing
within RCU such as in rcu_do_batch and switch everything to just
batching. Currently we don't do that since timer subsystem is not yet up
and we cannot schedule the kfree_rcu() monitor as the timer subsystem's
lock are not initialized. That would also mean getting rid of
kfree_call_rcu_nobatch() entirely.
[1] http://lore.kernel.org/lkml/20190723035725-mutt-send-email-mst@kernel.org
[2] https://lkml.org/lkml/2017/12/19/824
Cc: kernel-team@android.com
Cc: kernel-team@lge.com
Co-developed-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Applied 0day and Paul Walmsley feedback on ->monitor_todo. ]
[ paulmck: Make it work during early boot. ]
[ paulmck: Add a crude early boot self-test. ]
[ paulmck: Style adjustments and experimental docbook structure header. ]
Link: https://lore.kernel.org/lkml/alpine.DEB.2.21.9999.1908161931110.32497@viisi.sifive.com/T/#me9956f66cb611b95d26ae92700e1d901f46e8c59
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
head is traversed using hlist_for_each_entry_rcu outside an RCU
read-side critical section but under the protection of dtab->index_lock.
Hence, add corresponding lockdep expression to silence false-positive
lockdep warnings, and harden RCU lists.
Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Signed-off-by: Amol Grover <frextrite@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200123120437.26506-1-frextrite@gmail.com
- Fix a function comparison warning for a xen trace event macro
- Fix a double perf_event linking to a trace_uprobe_filter for multiple events
- Fix suspicious RCU warnings in trace event code for using
list_for_each_entry_rcu() when the "_rcu" portion wasn't needed.
- Fix a bug in the histogram code when using the same variable
- Fix a NULL pointer dereference when tracefs lockdown enabled and calling
trace_set_default_clock()
This v2 version contains:
- A fix to a bug found with the double perf_event linking patch
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXinakBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qhNZAQCi86p9eW3f3w7hM2hZcirC+mQKVZgp
2rO4zIAK5V6G7gEAh6I7VZa50a6AE647ZjryE7ufTRUhmSFMWoG0kcJ7OAk=
=/J9n
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Various tracing fixes:
- Fix a function comparison warning for a xen trace event macro
- Fix a double perf_event linking to a trace_uprobe_filter for
multiple events
- Fix suspicious RCU warnings in trace event code for using
list_for_each_entry_rcu() when the "_rcu" portion wasn't needed.
- Fix a bug in the histogram code when using the same variable
- Fix a NULL pointer dereference when tracefs lockdown enabled and
calling trace_set_default_clock()
- A fix to a bug found with the double perf_event linking patch"
* tag 'trace-v5.5-rc6-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/uprobe: Fix to make trace_uprobe_filter alignment safe
tracing: Do not set trace clock if tracefs lockdown is in effect
tracing: Fix histogram code when expression has same var as value
tracing: trigger: Replace unneeded RCU-list traversals
tracing/uprobe: Fix double perf_event linking on multiprobe uprobe
tracing: xen: Ordered comparison of function pointers
Prevent the kernel from crashing during resume from hibernation
if free pages contain leftover data from the restore kernel and
init_on_free is set (Alexander Potapenko).
-----BEGIN PGP SIGNATURE-----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=kDFG
-----END PGP SIGNATURE-----
Merge tag 'pm-5.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"Prevent the kernel from crashing during resume from hibernation if
free pages contain leftover data from the restore kernel and
init_on_free is set (Alexander Potapenko)"
* tag 'pm-5.5-rc8' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: hibernate: fix crashes with init_on_free=1
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-01-22
The following pull-request contains BPF updates for your *net-next* tree.
We've added 92 non-merge commits during the last 16 day(s) which contain
a total of 320 files changed, 7532 insertions(+), 1448 deletions(-).
The main changes are:
1) function by function verification and program extensions from Alexei.
2) massive cleanup of selftests/bpf from Toke and Andrii.
3) batched bpf map operations from Brian and Yonghong.
4) tcp congestion control in bpf from Martin.
5) bulking for non-map xdp_redirect form Toke.
6) bpf_send_signal_thread helper from Yonghong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds a helper to read the 64bit jiffies. It will be used
in a later patch to implement the bpf_cubic.c.
The helper is inlined for jit_requested and 64 BITS_PER_LONG
as the map_gen_lookup(). Other cases could be considered together
with map_gen_lookup() if needed.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200122233646.903260-1-kafai@fb.com
Introduce dynamic program extensions. The users can load additional BPF
functions and replace global functions in previously loaded BPF programs while
these programs are executing.
Global functions are verified individually by the verifier based on their types only.
Hence the global function in the new program which types match older function can
safely replace that corresponding function.
This new function/program is called 'an extension' of old program. At load time
the verifier uses (attach_prog_fd, attach_btf_id) pair to identify the function
to be replaced. The BPF program type is derived from the target program into
extension program. Technically bpf_verifier_ops is copied from target program.
The BPF_PROG_TYPE_EXT program type is a placeholder. It has empty verifier_ops.
The extension program can call the same bpf helper functions as target program.
Single BPF_PROG_TYPE_EXT type is used to extend XDP, SKB and all other program
types. The verifier allows only one level of replacement. Meaning that the
extension program cannot recursively extend an extension. That also means that
the maximum stack size is increasing from 512 to 1024 bytes and maximum
function nesting level from 8 to 16. The programs don't always consume that
much. The stack usage is determined by the number of on-stack variables used by
the program. The verifier could have enforced 512 limit for combined original
plus extension program, but it makes for difficult user experience. The main
use case for extensions is to provide generic mechanism to plug external
programs into policy program or function call chaining.
BPF trampoline is used to track both fentry/fexit and program extensions
because both are using the same nop slot at the beginning of every BPF
function. Attaching fentry/fexit to a function that was replaced is not
allowed. The opposite is true as well. Replacing a function that currently
being analyzed with fentry/fexit is not allowed. The executable page allocated
by BPF trampoline is not used by program extensions. This inefficiency will be
optimized in future patches.
Function by function verification of global function supports scalars and
pointer to context only. Hence program extensions are supported for such class
of global functions only. In the future the verifier will be extended with
support to pointers to structures, arrays with sizes, etc.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20200121005348.2769920-2-ast@kernel.org
The affinity of managed interrupts is completely handled in the kernel and
cannot be changed via the /proc/irq/* interfaces from user space. As the
kernel tries to spread out interrupts evenly accross CPUs on x86 to prevent
vector exhaustion, it can happen that a managed interrupt whose affinity
mask contains both isolated and housekeeping CPUs is routed to an isolated
CPU. As a consequence IO submitted on a housekeeping CPU causes interrupts
on the isolated CPU.
Add a new sub-parameter 'managed_irq' for 'isolcpus' and the corresponding
logic in the interrupt affinity selection code.
The subparameter indicates to the interrupt affinity selection logic that
it should try to avoid the above scenario.
This isolation is best effort and only effective if the automatically
assigned interrupt mask of a device queue contains isolated and
housekeeping CPUs. If housekeeping CPUs are online then such interrupts are
directed to the housekeeping CPU so that IO submitted on the housekeeping
CPU cannot disturb the isolated CPU.
If a queue's affinity mask contains only isolated CPUs then this parameter
has no effect on the interrupt routing decision, though interrupts are only
happening when tasks running on those isolated CPUs submit IO. IO submitted
on housekeeping CPUs has no influence on those queues.
If the affinity mask contains both housekeeping and isolated CPUs, but none
of the contained housekeeping CPUs is online, then the interrupt is also
routed to an isolated CPU. Interrupts are only delivered when one of the
isolated CPUs in the affinity mask submits IO. If one of the contained
housekeeping CPUs comes online, the CPU hotplug logic migrates the
interrupt automatically back to the upcoming housekeeping CPU. Depending on
the type of interrupt controller, this can require that at least one
interrupt is delivered to the isolated CPU in order to complete the
migration.
[ tglx: Removed unused parameter, added and edited comments/documentation
and rephrased the changelog so it contains more details. ]
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200120091625.17912-1-ming.lei@redhat.com
Commit 99c9a923e9 ("tracing/uprobe: Fix double perf_event
linking on multiprobe uprobe") moved trace_uprobe_filter on
trace_probe_event. However, since it introduced a flexible
data structure with char array and type casting, the
alignment of trace_uprobe_filter can be broken.
This changes the type of the array to trace_uprobe_filter
data strucure to fix it.
Link: http://lore.kernel.org/r/20200120124022.GA14897@hirez.programming.kicks-ass.net
Link: http://lkml.kernel.org/r/157966340499.5107.10978352478952144902.stgit@devnote2
Fixes: 99c9a923e9 ("tracing/uprobe: Fix double perf_event linking on multiprobe uprobe")
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This limitation are never lunched from introduce commit 970988e19e
("tracing/kprobe: Add kprobe_event= boot parameter")
Could we remove it if no intention to implement it?
Link: http://lkml.kernel.org/r/1579586075-45132-1-git-send-email-alex.shi@linux.alibaba.com
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If we exit due to a bad input to trace_printk() (highly unlikely), then the
buffer variable will not be initialized when we unnest the ring buffer.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Restore the 'if (env->cur_state)' check that was incorrectly removed during
code move. Under memory pressure env->cur_state can be freed and zeroed inside
do_check(). Hence the check is necessary.
Fixes: 51c39bb1d5 ("bpf: Introduce function-by-function verification")
Reported-by: syzbot+b296579ba5015704d9fa@syzkaller.appspotmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200122024138.3385590-1-ast@kernel.org
Though the second half of trampoline page is unused a task could be
preempted in the middle of the first half of trampoline and two
updates to trampoline would change the code from underneath the
preempted task. Hence wait for tasks to voluntarily schedule or go
to userspace. Add similar wait before freeing the trampoline.
Fixes: fec56f5890 ("bpf: Introduce BPF trampoline")
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/bpf/20200121032231.3292185-1-ast@kernel.org
kernel/bpf/inode.c misuses kern_path...() - it's much simpler (and
more efficient, on top of that) to use user_path...() counterparts
rather than bothering with doing getname() manually.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200120232858.GF8904@ZenIV.linux.org.uk
Generic update/delete batch ops functions were using __bpf_copy_key
without properly freeing the memory. Handle the memory allocation and
copy_from_user separately.
Fixes: aa2e93b8e5 ("bpf: Add generic support for update and delete batch ops")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200119194040.128369-1-brianvv@google.com
When trace_clock option is not set and unstable clcok detected,
tracing_set_default_clock() sets trace_clock(ThinkPad A285 is one of
case). In that case, if lockdown is in effect, null pointer
dereference error happens in ring_buffer_set_clock().
Link: http://lkml.kernel.org/r/20200116131236.3866925-1-masami256@gmail.com
Cc: stable@vger.kernel.org
Fixes: 17911ff38a ("tracing: Add locked_down checks to the open calls of files created for tracefs")
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1788488
Signed-off-by: Masami Ichikawa <masami256@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
While working on a tool to convert SQL syntex into the histogram language of
the kernel, I discovered the following bug:
# echo 'first u64 start_time u64 end_time pid_t pid u64 delta' >> synthetic_events
# echo 'hist:keys=pid:start=common_timestamp' > events/sched/sched_waking/trigger
# echo 'hist:keys=next_pid:delta=common_timestamp-$start,start2=$start:onmatch(sched.sched_waking).trace(first,$start2,common_timestamp,next_pid,$delta)' > events/sched/sched_switch/trigger
Would not display any histograms in the sched_switch histogram side.
But if I were to swap the location of
"delta=common_timestamp-$start" with "start2=$start"
Such that the last line had:
# echo 'hist:keys=next_pid:start2=$start,delta=common_timestamp-$start:onmatch(sched.sched_waking).trace(first,$start2,common_timestamp,next_pid,$delta)' > events/sched/sched_switch/trigger
The histogram works as expected.
What I found out is that the expressions clear out the value once it is
resolved. As the variables are resolved in the order listed, when
processing:
delta=common_timestamp-$start
The $start is cleared. When it gets to "start2=$start", it errors out with
"unresolved symbol" (which is silent as this happens at the location of the
trace), and the histogram is dropped.
When processing the histogram for variable references, instead of adding a
new reference for a variable used twice, use the same reference. That way,
not only is it more efficient, but the order will no longer matter in
processing of the variables.
From Tom Zanussi:
"Just to clarify some more about what the problem was is that without
your patch, we would have two separate references to the same variable,
and during resolve_var_refs(), they'd both want to be resolved
separately, so in this case, since the first reference to start wasn't
part of an expression, it wouldn't get the read-once flag set, so would
be read normally, and then the second reference would do the read-once
read and also be read but using read-once. So everything worked and
you didn't see a problem:
from: start2=$start,delta=common_timestamp-$start
In the second case, when you switched them around, the first reference
would be resolved by doing the read-once, and following that the second
reference would try to resolve and see that the variable had already
been read, so failed as unset, which caused it to short-circuit out and
not do the trigger action to generate the synthetic event:
to: delta=common_timestamp-$start,start2=$start
With your patch, we only have the single resolution which happens
correctly the one time it's resolved, so this can't happen."
Link: https://lore.kernel.org/r/20200116154216.58ca08eb@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 067fe038e7 ("tracing: Add variable reference handling to hist triggers")
Reviewed-by: Tom Zanuss <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In setup_load_info(), info->name (which contains the name of the module,
mostly used for early logging purposes before the module gets set up)
gets unconditionally assigned if .modinfo is missing despite the fact
that there is an if (!info->name) check near the end of the function.
Avoid assigning a placeholder string to info->name if .modinfo doesn't
exist, so that we can fall back to info->mod->name later on.
Fixes: 5fdc7db644 ("module: setup load info before module_sig_check()")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
sched_idle_cpu() isn't used for non SMP configuration and with a recent
change, we have started getting following warning:
kernel/sched/fair.c:5221:12: warning: ‘sched_idle_cpu’ defined but not used [-Wunused-function]
Fix that by defining sched_idle_cpu() only for SMP configurations.
Fixes: 323af6deaf ("sched/fair: Load balance aggressively for SCHED_IDLE CPUs")
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/f0554f590687478b33914a4aff9f0e6a62886d44.1579499907.git.viresh.kumar@linaro.org
This reverts commit 786b2384bf ("um: Enable CONFIG_CONSTRUCTORS").
There are two issues with this commit, uncovered by Anton in tests
on some (Debian) systems:
1) I completely forgot to call any constructors if CONFIG_CONSTRUCTORS
isn't set. Don't recall now if it just wasn't needed on my system, or
if I never tested this case.
2) With that fixed, it works - with CONFIG_CONSTRUCTORS *unset*. If I
set CONFIG_CONSTRUCTORS, it fails again, which isn't totally
unexpected since whatever wanted to run is likely to have to run
before the kernel init etc. that calls the constructors in this case.
Basically, some constructors that gcc emits (libc has?) need to run
very early during init; the failure mode otherwise was that the ptrace
fork test already failed:
----------------------
$ ./linux mem=512M
Core dump limits :
soft - 0
hard - NONE
Checking that ptrace can change system call numbers...check_ptrace : child exited with exitcode 6, while expecting 0; status 0x67f
Aborted
----------------------
Thinking more about this, it's clear that we simply cannot support
CONFIG_CONSTRUCTORS in UML. All the cases we need now (gcov, kasan)
involve not use of the __attribute__((constructor)), but instead
some constructor code/entry generated by gcc. Therefore, we cannot
distinguish between kernel constructors and system constructors.
Thus, revert this commit.
Cc: stable@vger.kernel.org [5.4+]
Fixes: 786b2384bf ("um: Enable CONFIG_CONSTRUCTORS")
Reported-by: Anton Ivanov <anton.ivanov@cambridgegreys.com>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Acked-by: Anton Ivanov <anton.ivanov@cambridgegreys.co.uk>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull networking fixes from David Miller:
1) Fix non-blocking connect() in x25, from Martin Schiller.
2) Fix spurious decryption errors in kTLS, from Jakub Kicinski.
3) Netfilter use-after-free in mtype_destroy(), from Cong Wang.
4) Limit size of TSO packets properly in lan78xx driver, from Eric
Dumazet.
5) r8152 probe needs an endpoint sanity check, from Johan Hovold.
6) Prevent looping in tcp_bpf_unhash() during sockmap/tls free, from
John Fastabend.
7) hns3 needs short frames padded on transmit, from Yunsheng Lin.
8) Fix netfilter ICMP header corruption, from Eyal Birger.
9) Fix soft lockup when low on memory in hns3, from Yonglong Liu.
10) Fix NTUPLE firmware command failures in bnxt_en, from Michael Chan.
11) Fix memory leak in act_ctinfo, from Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (91 commits)
cxgb4: reject overlapped queues in TC-MQPRIO offload
cxgb4: fix Tx multi channel port rate limit
net: sched: act_ctinfo: fix memory leak
bnxt_en: Do not treat DSN (Digital Serial Number) read failure as fatal.
bnxt_en: Fix ipv6 RFS filter matching logic.
bnxt_en: Fix NTUPLE firmware command failures.
net: systemport: Fixed queue mapping in internal ring map
net: dsa: bcm_sf2: Configure IMP port for 2Gb/sec
net: dsa: sja1105: Don't error out on disabled ports with no phy-mode
net: phy: dp83867: Set FORCE_LINK_GOOD to default after reset
net: hns: fix soft lockup when there is not enough memory
net: avoid updating qdisc_xmit_lock_key in netdev_update_lockdep_key()
net/sched: act_ife: initalize ife->metalist earlier
netfilter: nat: fix ICMP header corruption on ICMP errors
net: wan: lapbether.c: Use built-in RCU list checking
netfilter: nf_tables: fix flowtable list del corruption
netfilter: nf_tables: fix memory leak in nf_tables_parse_netdev_hooks()
netfilter: nf_tables: remove WARN and add NLA_STRING upper limits
netfilter: nft_tunnel: ERSPAN_VERSION must not be null
netfilter: nft_tunnel: fix null-attribute check
...
Pull timer fixes from Ingo Molnar:
"Three fixes: fix link failure on Alpha, fix a Sparse warning and
annotate/robustify a lockless access in the NOHZ code"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/sched: Annotate lockless access to last_jiffies_update
lib/vdso: Make __cvdso_clock_getres() static
time/posix-stubs: Provide compat itimer supoprt for alpha
Pull cpu/SMT fix from Ingo Molnar:
"Fix a build bug on CONFIG_HOTPLUG_SMT=y && !CONFIG_SYSFS kernels"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/SMT: Fix x86 link error without CONFIG_SYSFS
Pull perf fixes from Ingo Molnar:
"Tooling fixes, three Intel uncore driver fixes, plus an AUX events fix
uncovered by the perf fuzzer"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel/uncore: Remove PCIe3 unit for SNR
perf/x86/intel/uncore: Fix missing marker for snr_uncore_imc_freerunning_events
perf/x86/intel/uncore: Add PCI ID of IMC for Xeon E3 V5 Family
perf: Correctly handle failed perf_get_aux_event()
perf hists: Fix variable name's inconsistency in hists__for_each() macro
perf map: Set kmap->kmaps backpointer for main kernel map chunks
perf report: Fix incorrectly added dimensions as switch perf data file
tools lib traceevent: Fix memory leakage in filter_event
Pull locking fixes from Ingo Molnar:
"Three fixes:
- Fix an rwsem spin-on-owner crash, introduced in v5.4
- Fix a lockdep bug when running out of stack_trace entries,
introduced in v5.4
- Docbook fix"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/rwsem: Fix kernel crash when spinning on RWSEM_OWNER_UNKNOWN
futex: Fix kernel-doc notation warning
locking/lockdep: Fix buffer overrun problem in stack_trace[]
Pull rseq fixes from Ingo Molnar:
"Two rseq bugfixes:
- CLONE_VM !CLONE_THREAD didn't work properly, the kernel would end
up corrupting the TLS of the parent. Technically a change in the
ABI but the previous behavior couldn't resonably have been relied
on by applications so this looks like a valid exception to the ABI
rule.
- Make the RSEQ_FLAG_UNREGISTER ABI behavior consistent with the
handling of other flags. This is not thought to impact any
applications either"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rseq: Unregister rseq for clone CLONE_VM
rseq: Reject unknown flags on rseq unregister
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXiL/qwAKCRCRxhvAZXjc
oln5AP9ITypHs2iNWl1Cbte++y2iflWevDyPUrmagegqpKwbJAD9EypY0RVDor8T
LXWK4WaNgB0K0MK/gSPRAlgx9ejNwA4=
=6xXo
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2020-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread fixes from Christian Brauner:
"Here is an urgent fix for ptrace_may_access() permission checking.
Commit 69f594a389 ("ptrace: do not audit capability check when
outputing /proc/pid/stat") introduced the ability to opt out of audit
messages for accesses to various proc files since they are not
violations of policy.
While doing so it switched the check from ns_capable() to
has_ns_capability{_noaudit}(). That means it switched from checking
the subjective credentials (ktask->cred) of the task to using the
objective credentials (ktask->real_cred). This is appears to be wrong.
ptrace_has_cap() is currently only used in ptrace_may_access() And is
used to check whether the calling task (subject) has the
CAP_SYS_PTRACE capability in the provided user namespace to operate on
the target task (object). According to the cred.h comments this means
the subjective credentials of the calling task need to be used.
With this fix we switch ptrace_has_cap() to use security_capable() and
thus back to using the subjective credentials.
As one example where this might be particularly problematic, Jann
pointed out that in combination with the upcoming IORING_OP_OPENAT{2}
feature, this bug might allow unprivileged users to bypass the
capability checks while asynchronously opening files like /proc/*/mem,
because the capability checks for this would be performed against
kernel credentials.
To illustrate on the former point about this being exploitable: When
io_uring creates a new context it records the subjective credentials
of the caller. Later on, when it starts to do work it creates a kernel
thread and registers a callback. The callback runs with kernel creds
for ktask->real_cred and ktask->cred.
To prevent this from becoming a full-blown 0-day io_uring will call
override_cred() and override ktask->cred with the subjective
credentials of the creator of the io_uring instance. With
ptrace_has_cap() currently looking at ktask->real_cred this override
will be ineffective and the caller will be able to open arbitray proc
files as mentioned above.
Luckily, this is currently not exploitable but would be so once
IORING_OP_OPENAT{2} land in v5.6. Let's fix it now.
To minimize potential regressions I successfully ran the criu
testsuite. criu makes heavy use of ptrace() and extensively hits
ptrace_may_access() codepaths and has a good change of detecting any
regressions.
Additionally, I succesfully ran the ptrace and seccomp kernel tests"
* tag 'for-linus-2020-01-18' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
ptrace: reintroduce usage of subjective credentials in ptrace_has_cap()
Commit 69f594a389 ("ptrace: do not audit capability check when outputing /proc/pid/stat")
introduced the ability to opt out of audit messages for accesses to various
proc files since they are not violations of policy. While doing so it
somehow switched the check from ns_capable() to
has_ns_capability{_noaudit}(). That means it switched from checking the
subjective credentials of the task to using the objective credentials. This
is wrong since. ptrace_has_cap() is currently only used in
ptrace_may_access() And is used to check whether the calling task (subject)
has the CAP_SYS_PTRACE capability in the provided user namespace to operate
on the target task (object). According to the cred.h comments this would
mean the subjective credentials of the calling task need to be used.
This switches ptrace_has_cap() to use security_capable(). Because we only
call ptrace_has_cap() in ptrace_may_access() and in there we already have a
stable reference to the calling task's creds under rcu_read_lock() there's
no need to go through another series of dereferences and rcu locking done
in ns_capable{_noaudit}().
As one example where this might be particularly problematic, Jann pointed
out that in combination with the upcoming IORING_OP_OPENAT feature, this
bug might allow unprivileged users to bypass the capability checks while
asynchronously opening files like /proc/*/mem, because the capability
checks for this would be performed against kernel credentials.
To illustrate on the former point about this being exploitable: When
io_uring creates a new context it records the subjective credentials of the
caller. Later on, when it starts to do work it creates a kernel thread and
registers a callback. The callback runs with kernel creds for
ktask->real_cred and ktask->cred. To prevent this from becoming a
full-blown 0-day io_uring will call override_cred() and override
ktask->cred with the subjective credentials of the creator of the io_uring
instance. With ptrace_has_cap() currently looking at ktask->real_cred this
override will be ineffective and the caller will be able to open arbitray
proc files as mentioned above.
Luckily, this is currently not exploitable but will turn into a 0-day once
IORING_OP_OPENAT{2} land in v5.6. Fix it now!
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Eric Paris <eparis@redhat.com>
Cc: stable@vger.kernel.org
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Reviewed-by: Jann Horn <jannh@google.com>
Fixes: 69f594a389 ("ptrace: do not audit capability check when outputing /proc/pid/stat")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
The low resolution parts of the VDSO, i.e.:
clock_gettime(CLOCK_*_COARSE), clock_getres(), time()
can be used even if there is no VDSO capable clocksource.
But if an architecture opts out of the VDSO data update then this
information becomes stale. This affects ARM when there is no architected
timer available. The lack of update causes userspace to use stale data
forever.
Make the update of the low resolution parts unconditional and only skip
the update of the high resolution parts if the architecture requests it.
Fixes: 44f57d788e ("timekeeping: Provide a generic update_vsyscall() implementation")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200114185946.765577901@linutronix.de
The function name suggests that this is a boolean checking whether the
architecture asks for an update of the VDSO data, but it works the other
way round. To spare further confusion invert the logic.
Fixes: 44f57d788e ("timekeeping: Provide a generic update_vsyscall() implementation")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200114185946.656652824@linutronix.de
Vince reports a worrying issue:
| so I was tracking down some odd behavior in the perf_fuzzer which turns
| out to be because perf_even_open() sometimes returns 0 (indicating a file
| descriptor of 0) even though as far as I can tell stdin is still open.
... and further the cause:
| error is triggered if aux_sample_size has non-zero value.
|
| seems to be this line in kernel/events/core.c:
|
| if (perf_need_aux_event(event) && !perf_get_aux_event(event, group_leader))
| goto err_locked;
|
| (note, err is never set)
This seems to be a thinko in commit:
ab43762ef0 ("perf: Allow normal events to output AUX data")
... and we should probably return -EINVAL here, as this should only
happen when the new event is mis-configured or does not have a
compatible aux_event group leader.
Fixes: ab43762ef0 ("perf: Allow normal events to output AUX data")
Reported-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Tested-by: Vince Weaver <vincent.weaver@maine.edu>
Robert reported that during boot the watchdog timestamp is set to 0 for one
second which is the indicator for a watchdog reset.
The reason for this is that the timestamp is in seconds and the time is
taken from sched clock and divided by ~1e9. sched clock starts at 0 which
means that for the first second during boot the watchdog timestamp is 0,
i.e. reset.
Use ULONG_MAX as the reset indicator value so the watchdog works correctly
right from the start. ULONG_MAX would only conflict with a real timestamp
if the system reaches an uptime of 136 years on 32bit and almost eternity
on 64bit.
Reported-by: Robert Richter <rrichter@marvell.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/87o8v3uuzl.fsf@nanos.tec.linutronix.de
Arm64 has a more optimized spinning loop (atomic_cond_read_acquire)
using wfe for spinlock that can boost performance of sibling threads
by putting the current cpu to a wait state that is broken only when
the monitored variable changes or an external event happens.
OSQ has a more complicated spinning loop. Besides the lock value, it
also checks for need_resched() and vcpu_is_preempted(). The check for
need_resched() is not a problem as it is only set by the tick interrupt
handler. That will be detected by the spinning cpu right after iret.
The vcpu_is_preempted() check, however, is a problem as changes to the
preempt state of of previous node will not affect the wait state. For
ARM64, vcpu_is_preempted is not currently defined and so is a no-op.
Will has indicated that he is planning to para-virtualize wfe instead
of defining vcpu_is_preempted for PV support. So just add a comment in
arch/arm64/include/asm/spinlock.h to indicate that vcpu_is_preempted()
should not be defined as suggested.
On a 2-socket 56-core 224-thread ARM64 system, a kernel mutex locking
microbenchmark was run for 10s with and without the patch. The
performance numbers before patch were:
Running locktest with mutex [runtime = 10s, load = 1]
Threads = 224, Min/Mean/Max = 316/123,143/2,121,269
Threads = 224, Total Rate = 2,757 kop/s; Percpu Rate = 12 kop/s
After patch, the numbers were:
Running locktest with mutex [runtime = 10s, load = 1]
Threads = 224, Min/Mean/Max = 334/147,836/1,304,787
Threads = 224, Total Rate = 3,311 kop/s; Percpu Rate = 15 kop/s
So there was about 20% performance improvement.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20200113150735.21956-1-longman@redhat.com
It was found that two lines in the output of /proc/lockdep_stats have
indentation problem:
# cat /proc/lockdep_stats
:
in-process chains: 25057
stack-trace entries: 137827 [max: 524288]
number of stack traces: 7973
number of stack hash chains: 6355
combined max dependencies: 1356414598
hardirq-safe locks: 57
hardirq-unsafe locks: 1286
:
All the numbers displayed in /proc/lockdep_stats except the two stack
trace numbers are formatted with a field with of 11. To properly align
all the numbers, a field width of 11 is now added to the two stack
trace numbers.
Fixes: 8c779229d0 ("locking/lockdep: Report more stack trace statistics")
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Link: https://lkml.kernel.org/r/20191211213139.29934-1-longman@redhat.com
The commit 91d2a812df ("locking/rwsem: Make handoff writer
optimistically spin on owner") will allow a recently woken up waiting
writer to spin on the owner. Unfortunately, if the owner happens to be
RWSEM_OWNER_UNKNOWN, the code will incorrectly spin on it leading to a
kernel crash. This is fixed by passing the proper non-spinnable bits
to rwsem_spin_on_owner() so that RWSEM_OWNER_UNKNOWN will be treated
as a non-spinnable target.
Fixes: 91d2a812df ("locking/rwsem: Make handoff writer optimistically spin on owner")
Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200115154336.8679-1-longman@redhat.com
topology.c::get_group() relies on the assumption that non-NUMA domains do
not partially overlap. Zeng Tao pointed out in [1] that such topology
descriptions, while completely bogus, can end up being exposed to the
scheduler.
In his example (8 CPUs, 2-node system), we end up with:
MC span for CPU3 == 3-7
MC span for CPU4 == 4-7
The first pass through get_group(3, sdd@MC) will result in the following
sched_group list:
3 -> 4 -> 5 -> 6 -> 7
^ /
`----------------'
And a later pass through get_group(4, sdd@MC) will "corrupt" that to:
3 -> 4 -> 5 -> 6 -> 7
^ /
`-----------'
which will completely break things like 'while (sg != sd->groups)' when
using CPU3's base sched_domain.
There already are some architecture-specific checks in place such as
x86/kernel/smpboot.c::topology.sane(), but this is something we can detect
in the core scheduler, so it seems worthwhile to do so.
Warn and abort the construction of the sched domains if such a broken
topology description is detected. Note that this is somewhat
expensive (O(t.c²), 't' non-NUMA topology levels and 'c' CPUs) and could be
gated under SCHED_DEBUG if deemed necessary.
Testing
=======
Dietmar managed to reproduce this using the following qemu incantation:
$ qemu-system-aarch64 -kernel ./Image -hda ./qemu-image-aarch64.img \
-append 'root=/dev/vda console=ttyAMA0 loglevel=8 sched_debug' -smp \
cores=8 --nographic -m 512 -cpu cortex-a53 -machine virt -numa \
node,cpus=0-2,nodeid=0 -numa node,cpus=3-7,nodeid=1
alongside the following drivers/base/arch_topology.c hack (AIUI wouldn't be
needed if '-smp cores=X, sockets=Y' would work with qemu):
8<---
@@ -465,6 +465,9 @@ void update_siblings_masks(unsigned int cpuid)
if (cpuid_topo->package_id != cpu_topo->package_id)
continue;
+ if ((cpu < 4 && cpuid > 3) || (cpu > 3 && cpuid < 4))
+ continue;
+
cpumask_set_cpu(cpuid, &cpu_topo->core_sibling);
cpumask_set_cpu(cpu, &cpuid_topo->core_sibling);
8<---
[1]: https://lkml.kernel.org/r/1577088979-8545-1-git-send-email-prime.zeng@hisilicon.com
Reported-by: Zeng Tao <prime.zeng@hisilicon.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200115160915.22575-1-valentin.schneider@arm.com
There is a spelling misake in comments of cpuidle_idle_call. Fix it.
Signed-off-by: Hewenliang <hewenliang4@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20200110025604.34373-1-hewenliang4@huawei.com
With commit
bef69dd878 ("sched/cpufreq: Move the cfs_rq_util_change() call to cpufreq_update_util()")
update_load_avg() has become the central point for calling cpufreq
(not including the update of blocked load). This change helps to
simplify further the number of calls to cpufreq_update_util() and to
remove last redundant ones. With update_load_avg(), we are now sure
that cpufreq_update_util() will be called after every task attachment
to a cfs_rq and especially after propagating this event down to the
util_avg of the root cfs_rq, which is the level that is used by
cpufreq governors like schedutil to set the frequency of a CPU.
The SCHED_CPUFREQ_MIGRATION flag forces an early call to cpufreq when
the migration happens in a cgroup whereas util_avg of root cfs_rq is
not yet updated and this call is duplicated with the one that happens
immediately after when the migration event reaches the root cfs_rq.
The dedicated flag SCHED_CPUFREQ_MIGRATION is now useless and can be
removed. The interface of attach_entity_load_avg() can also be
simplified accordingly.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lkml.kernel.org/r/1579083620-24943-1-git-send-email-vincent.guittot@linaro.org
when CONFIG_PSI_DEFAULT_DISABLED set to N or the command line set psi=0,
I think we should not create /proc/pressure and
/proc/pressure/{io|memory|cpu}.
In the future, user maybe determine whether the psi feature is enabled by
checking the existence of the /proc/pressure dir or
/proc/pressure/{io|memory|cpu} files.
Signed-off-by: Wang Long <w@laoqinren.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lkml.kernel.org/r/1576672698-32504-1-git-send-email-w@laoqinren.net
commit bf475ce0a3 ("sched/fair: Add per-CPU min capacity to
sched_group_capacity") introduced per-cpu min_capacity.
commit e3d6d0cb66 ("sched/fair: Add sched_group per-CPU max capacity")
introduced per-cpu max_capacity.
In the SD_OVERLAP case, the local variable 'capacity' represents the sum
of CPU capacity of all CPUs in the first sched group (sg) of the sched
domain (sd).
It is erroneously used to calculate sg's min and max CPU capacity.
To fix this use capacity_of(cpu) instead of 'capacity'.
The code which achieves this via cpu_rq(cpu)->sd->groups->sgc->capacity
(for rq->sd != NULL) can be removed since it delivers the same value as
capacity_of(cpu) which is currently only used for the (!rq->sd) case
(see update_cpu_capacity()).
An sg of the lowest sd (rq->sd or sd->child == NULL) represents a single
CPU (and hence sg->sgc->capacity == capacity_of(cpu)).
Signed-off-by: Peng Liu <iwtbavbm@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20200104130828.GA7718@iZj6chx1xj0e0buvshuecpZ
Move the code of calculation for delta_sum/delta_avg to where
it is really needed to be done.
Signed-off-by: Peng Wang <rocking@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20200103114400.17668-1-rocking@linux.alibaba.com
Every time we call irqtime_account_process_tick() is in a interrupt,
Every caller will get and assign a parameter rq = this_rq(), This is
unnecessary and increase the code size a little bit. Move the rq getting
action to irqtime_account_process_tick internally is better.
base with this patch
cputime.o 578792 bytes 577888 bytes
Signed-off-by: Alex Shi <alex.shi@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1577959674-255537-1-git-send-email-alex.shi@linux.alibaba.com
The function stop_cpus() is only used internally by the
stop_machine for stop multiple cpus.
Make it static.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191228161912.24082-1-tiny.windzz@gmail.com
Lengthy output of sysrq-t may take a lot of time on slow serial console
with lots of processes and CPUs.
So we need to reset NMI-watchdog to avoid spurious lockup messages, and
we also reset softlockup watchdogs on all other CPUs since another CPU
might be blocked waiting for us to process an IPI or stop_machine.
Add to sysrq_sched_debug_show() as what we did in show_state_filter().
Signed-off-by: Wei Li <liwei391@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20191226085224.48942-1-liwei391@huawei.com
rq::uclamp is an array of struct uclamp_rq, make sure we clear the
whole thing.
Fixes: 69842cba9a ("sched/uclamp: Add CPU's clamp buckets refcountinga")
Signed-off-by: Li Guanglei <guanglei.li@unisoc.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Link: https://lkml.kernel.org/r/1577259844-12677-1-git-send-email-guangleix.li@gmail.com
When a new cgroup is created, the effective uclamp value wasn't updated
with a call to cpu_util_update_eff() that looks at the hierarchy and
update to the most restrictive values.
Fix it by ensuring to call cpu_util_update_eff() when a new cgroup
becomes online.
Without this change, the newly created cgroup uses the default
root_task_group uclamp values, which is 1024 for both uclamp_{min, max},
which will cause the rq to to be clamped to max, hence cause the
system to run at max frequency.
The problem was observed on Ubuntu server and was reproduced on Debian
and Buildroot rootfs.
By default, Ubuntu and Debian create a cpu controller cgroup hierarchy
and add all tasks to it - which creates enough noise to keep the rq
uclamp value at max most of the time. Imitating this behavior makes the
problem visible in Buildroot too which otherwise looks fine since it's a
minimal userspace.
Fixes: 0b60ba2dd3 ("sched/uclamp: Propagate parent clamps")
Reported-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Doug Smythies <dsmythies@telus.net>
Link: https://lore.kernel.org/lkml/000701d5b965$361b6c60$a2524520$@net/
The fair scheduler performs periodic load balance on every CPU to check
if it can pull some tasks from other busy CPUs. The duration of this
periodic load balance is set to sd->balance_interval for the idle CPUs
and is calculated by multiplying the sd->balance_interval with the
sd->busy_factor (set to 32 by default) for the busy CPUs. The
multiplication is done for busy CPUs to avoid doing load balance too
often and rather spend more time executing actual task. While that is
the right thing to do for the CPUs busy with SCHED_OTHER or SCHED_BATCH
tasks, it may not be the optimal thing for CPUs running only SCHED_IDLE
tasks.
With the recent enhancements in the fair scheduler around SCHED_IDLE
CPUs, we now prefer to enqueue a newly-woken task to a SCHED_IDLE
CPU instead of other busy or idle CPUs. The same reasoning should be
applied to the load balancer as well to make it migrate tasks more
aggressively to a SCHED_IDLE CPU, as that will reduce the scheduling
latency of the migrated (SCHED_OTHER) tasks.
This patch makes minimal changes to the fair scheduler to do the next
load balance soon after the last non SCHED_IDLE task is dequeued from a
runqueue, i.e. making the CPU SCHED_IDLE. Also the sd->busy_factor is
ignored while calculating the balance_interval for such CPUs. This is
done to avoid delaying the periodic load balance by few hundred
milliseconds for SCHED_IDLE CPUs.
This is tested on ARM64 Hikey620 platform (octa-core) with the help of
rt-app and it is verified, using kernel traces, that the newly
SCHED_IDLE CPU does load balancing shortly after it becomes SCHED_IDLE
and pulls tasks from other busy CPUs.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/e485827eb8fe7db0943d6f3f6e0f5a4a70272781.1578471925.git.viresh.kumar@linaro.org
Similarly to calculate_imbalance() and find_busiest_group(), using the
number of idle CPUs when there is only 1 CPU in the group is not efficient
because we can't make a difference between a CPU running 1 task and a CPU
running dozens of small tasks competing for the same CPU but not enough
to overload it. More generally speaking, we should use the number of
running tasks when there is the same number of idle CPUs in a group instead
of blindly select the 1st one.
When the groups have spare capacity and the same number of idle CPUs, we
compare the number of running tasks to select the busiest group.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1576839893-26930-1-git-send-email-vincent.guittot@linaro.org
After commit 9cf57731b6 ("watchdog/softlockup: Replace "watchdog/%u"
threads with cpu_stop_work"), the percpu soft_lockup_hrtimer_cnt is
not used any more, so remove it and related code.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191218131720.4146aea2@xhacker.debian
If syscall_enter_define_fields() is called on a system call with no
arguments, the return code variable "ret" will never get initialized.
Initialize it to zero.
Fixes: 04ae87a520 ("ftrace: Rework event_create_dir()")
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/0FA8C6E3-D9F5-416D-A1B0-5E4CD583A101@lca.pw
kernel/bpf/syscall.c: In function generic_map_lookup_batch:
kernel/bpf/syscall.c:1339:7: warning: variable first_key set but not used [-Wunused-but-set-variable]
It is never used, so remove it.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Brian Vazquez <brianvv@google.com>
Link: https://lore.kernel.org/bpf/20200116145300.59056-1-yuehaibing@huawei.com
Now that we don't have a reference to a devmap when flushing the device
bulk queue, let's change the the devmap_xmit tracepoint to remote the
map_id and map_index fields entirely. Rearrange the fields so 'drops' and
'sent' stay in the same position in the tracepoint struct, to make it
possible for the xdp_monitor utility to read both the old and the new
format.
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/157918768613.1458396.9165902403373826572.stgit@toke.dk
Since the bulk queue used by XDP_REDIRECT now lives in struct net_device,
we can re-use the bulking for the non-map version of the bpf_redirect()
helper. This is a simple matter of having xdp_do_redirect_slow() queue the
frame on the bulk queue instead of sending it out with __bpf_tx_xdp().
Unfortunately we can't make the bpf_redirect() helper return an error if
the ifindex doesn't exit (as bpf_redirect_map() does), because we don't
have a reference to the network namespace of the ingress device at the time
the helper is called. So we have to leave it as-is and keep the device
lookup in xdp_do_redirect_slow().
Since this leaves less reason to have the non-map redirect code in a
separate function, so we get rid of the xdp_do_redirect_slow() function
entirely. This does lose us the tracepoint disambiguation, but fortunately
the xdp_redirect and xdp_redirect_map tracepoints use the same tracepoint
entry structures. This means both can contain a map index, so we can just
amend the tracepoint definitions so we always emit the xdp_redirect(_err)
tracepoints, but with the map ID only populated if a map is present. This
means we retire the xdp_redirect_map(_err) tracepoints entirely, but keep
the definitions around in case someone is still listening for them.
With this change, the performance of the xdp_redirect sample program goes
from 5Mpps to 8.4Mpps (a 68% increase).
Since the flush functions are no longer map-specific, rename the flush()
functions to drop _map from their names. One of the renamed functions is
the xdp_do_flush_map() callback used in all the xdp-enabled drivers. To
keep from having to update all drivers, use a #define to keep the old name
working, and only update the virtual drivers in this patch.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/157918768505.1458396.17518057312953572912.stgit@toke.dk
Commit 96360004b8 ("xdp: Make devmap flush_list common for all map
instances"), changed devmap flushing to be a global operation instead of a
per-map operation. However, the queue structure used for bulking was still
allocated as part of the containing map.
This patch moves the devmap bulk queue into struct net_device. The
motivation for this is reusing it for the non-map variant of XDP_REDIRECT,
which will be changed in a subsequent commit. To avoid other fields of
struct net_device moving to different cache lines, we also move a couple of
other members around.
We defer the actual allocation of the bulk queue structure until the
NETDEV_REGISTER notification devmap.c. This makes it possible to check for
ndo_xdp_xmit support before allocating the structure, which is not possible
at the time struct net_device is allocated. However, we keep the freeing in
free_netdev() to avoid adding another RCU callback on NETDEV_UNREGISTER.
Because of this change, we lose the reference back to the map that
originated the redirect, so change the tracepoint to always return 0 as the
map ID and index. Otherwise no functional change is intended with this
patch.
After this patch, the relevant part of struct net_device looks like this,
according to pahole:
/* --- cacheline 14 boundary (896 bytes) --- */
struct netdev_queue * _tx __attribute__((__aligned__(64))); /* 896 8 */
unsigned int num_tx_queues; /* 904 4 */
unsigned int real_num_tx_queues; /* 908 4 */
struct Qdisc * qdisc; /* 912 8 */
unsigned int tx_queue_len; /* 920 4 */
spinlock_t tx_global_lock; /* 924 4 */
struct xdp_dev_bulk_queue * xdp_bulkq; /* 928 8 */
struct xps_dev_maps * xps_cpus_map; /* 936 8 */
struct xps_dev_maps * xps_rxqs_map; /* 944 8 */
struct mini_Qdisc * miniq_egress; /* 952 8 */
/* --- cacheline 15 boundary (960 bytes) --- */
struct hlist_head qdisc_hash[16]; /* 960 128 */
/* --- cacheline 17 boundary (1088 bytes) --- */
struct timer_list watchdog_timer; /* 1088 40 */
/* XXX last struct has 4 bytes of padding */
int watchdog_timeo; /* 1128 4 */
/* XXX 4 bytes hole, try to pack */
struct list_head todo_list; /* 1136 16 */
/* --- cacheline 18 boundary (1152 bytes) --- */
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/157918768397.1458396.12673224324627072349.stgit@toke.dk
Upon resuming from hibernation, free pages may contain stale data from
the kernel that initiated the resume. This breaks the invariant
inflicted by init_on_free=1 that freed pages must be zeroed.
To deal with this problem, make clear_free_pages() also clear the free
pages when init_on_free is enabled.
Fixes: 6471384af2 ("mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options")
Reported-by: Johannes Stezenbach <js@sig21.net>
Signed-off-by: Alexander Potapenko <glider@google.com>
Cc: 5.3+ <stable@vger.kernel.org> # 5.3+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The sysfs attribute `/sys/power/sync_on_suspend` controls, whether or not
filesystems are synced by the kernel before system suspend.
Congruously, the behaviour of build-time switch CONFIG_SUSPEND_SKIP_SYNC
is slightly changed: It now defines the run-tim default for the new sysfs
attribute `/sys/power/sync_on_suspend`.
The run-time attribute is added because the existing corresponding
build-time Kconfig flag for (`CONFIG_SUSPEND_SKIP_SYNC`) is not flexible
enough. E.g. Linux distributions that provide pre-compiled kernels
usually want to stick with the default (sync filesystems before suspend)
but under special conditions this needs to be changed.
One example for such a special condition is user-space handling of
suspending block devices (e.g. using `cryptsetup luksSuspend` or `dmsetup
suspend`) before system suspend. The Kernel trying to sync filesystems
after the underlying block device already got suspended obviously leads
to dead-locks. Be aware that you have to take care of the filesystem sync
yourself before suspending the system in those scenarios.
Signed-off-by: Jonas Meurer <jonas@freesources.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
commit 9cf57731b6 ("watchdog/softlockup: Replace "watchdog/%u" threads
with cpu_stop_work") ensures that the watchdog is reliably touched during
a task switch.
As a result the check for an unnoticed task switch is not longer needed.
Remove the relevant code, which effectively reverts commit b1a8de1f53
("softlockup: make detector be aware of task switch of processes hogging
cpu")
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Ziljstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20191024114928.15377-2-pmladek@suse.com
trace_printk() is used to debug the kernel which includes the tracing
infrastructure. But because it writes to the ring buffer, and so does much
of the tracing infrastructure, the ring buffer's recursive detection will
drop writes to the ring buffer that is in the same context as the current
write is happening (it allows interrupts to write when normal context is
writing, but wont let normal context write while normal context is writing).
This can cause confusion and think that the code is where the trace_printk()
exists is not hit. To solve this, up the recursive nesting of the ring
buffer when trace_printk() is called before it writes to the buffer itself.
Note, this does make it dangerous to use trace_printk() in the ring buffer
code itself, because this basically disables the recursion protection of
trace_printk() buffer writes. But as trace_printk() is only used for
debugging, and if this does occur, the developer will see the cause real
quick (recursive blowing up of the stack). Thus the developer can deal with
that. But having trace_printk() silently ignored is a much bigger problem,
and disabling recursive protection is a small price to pay to fix it.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
After commit 9cf57731b6 ("watchdog/softlockup: Replace "watchdog/%u"
threads with cpu_stop_work"), the percpu soft_lockup_hrtimer_cnt is
not used any more, so remove it and related code.
Signed-off-by: Jisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191218131720.4146aea2@xhacker.debian
Daniel Borkmann says:
====================
pull-request: bpf 2020-01-15
The following pull-request contains BPF updates for your *net* tree.
We've added 12 non-merge commits during the last 9 day(s) which contain
a total of 13 files changed, 95 insertions(+), 43 deletions(-).
The main changes are:
1) Fix refcount leak for TCP time wait and request sockets for socket lookup
related BPF helpers, from Lorenz Bauer.
2) Fix wrong verification of ARSH instruction under ALU32, from Daniel Borkmann.
3) Batch of several sockmap and related TLS fixes found while operating
more complex BPF programs with Cilium and OpenSSL, from John Fastabend.
4) Fix sockmap to read psock's ingress_msg queue before regular sk_receive_queue()
to avoid purging data upon teardown, from Lingpeng Chen.
5) Fix printing incorrect pointer in bpftool's btf_dump_ptr() in order to properly
dump a BPF map's value with BTF, from Martin KaFai Lau.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
htab can't use generic batch support due some problematic behaviours
inherent to the data structre, i.e. while iterating the bpf map a
concurrent program might delete the next entry that batch was about to
use, in that case there's no easy solution to retrieve the next entry,
the issue has been discussed multiple times (see [1] and [2]).
The only way hmap can be traversed without the problem previously
exposed is by making sure that the map is traversing entire buckets.
This commit implements those strict requirements for hmap, the
implementation follows the same interaction that generic support with
some exceptions:
- If keys/values buffer are not big enough to traverse a bucket,
ENOSPC will be returned.
- out_batch contains the value of the next bucket in the iteration, not
the next key, but this is transparent for the user since the user
should never use out_batch for other than bpf batch syscalls.
This commits implements BPF_MAP_LOOKUP_BATCH and adds support for new
command BPF_MAP_LOOKUP_AND_DELETE_BATCH. Note that for update/delete
batch ops it is possible to use the generic implementations.
[1] https://lore.kernel.org/bpf/20190724165803.87470-1-brianvv@google.com/
[2] https://lore.kernel.org/bpf/20190906225434.3635421-1-yhs@fb.com/
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200115184308.162644-6-brianvv@google.com
This adds the generic batch ops functionality to bpf arraymap, note that
since deletion is not a valid operation for arraymap, only batch and
lookup are added.
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200115184308.162644-5-brianvv@google.com
This commit adds generic support for update and delete batch ops that
can be used for almost all the bpf maps. These commands share the same
UAPI attr that lookup and lookup_and_delete batch ops use and the
syscall commands are:
BPF_MAP_UPDATE_BATCH
BPF_MAP_DELETE_BATCH
The main difference between update/delete and lookup batch ops is that
for update/delete keys/values must be specified for userspace and
because of that, neither in_batch nor out_batch are used.
Suggested-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200115184308.162644-4-brianvv@google.com
This commit introduces generic support for the bpf_map_lookup_batch.
This implementation can be used by almost all the bpf maps since its core
implementation is relying on the existing map_get_next_key and
map_lookup_elem. The bpf syscall subcommand introduced is:
BPF_MAP_LOOKUP_BATCH
The UAPI attribute is:
struct { /* struct used by BPF_MAP_*_BATCH commands */
__aligned_u64 in_batch; /* start batch,
* NULL to start from beginning
*/
__aligned_u64 out_batch; /* output: next start batch */
__aligned_u64 keys;
__aligned_u64 values;
__u32 count; /* input/output:
* input: # of key/value
* elements
* output: # of filled elements
*/
__u32 map_fd;
__u64 elem_flags;
__u64 flags;
} batch;
in_batch/out_batch are opaque values use to communicate between
user/kernel space, in_batch/out_batch must be of key_size length.
To start iterating from the beginning in_batch must be null,
count is the # of key/value elements to retrieve. Note that the 'keys'
buffer must be a buffer of key_size * count size and the 'values' buffer
must be value_size * count, where value_size must be aligned to 8 bytes
by userspace if it's dealing with percpu maps. 'count' will contain the
number of keys/values successfully retrieved. Note that 'count' is an
input/output variable and it can contain a lower value after a call.
If there's no more entries to retrieve, ENOENT will be returned. If error
is ENOENT, count might be > 0 in case it copied some values but there were
no more entries to retrieve.
Note that if the return code is an error and not -EFAULT,
count indicates the number of elements successfully processed.
Suggested-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200115184308.162644-3-brianvv@google.com
This commit moves reusable code from map_lookup_elem and map_update_elem
to avoid code duplication in kernel/bpf/syscall.c.
Signed-off-by: Brian Vazquez <brianvv@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200115184308.162644-2-brianvv@google.com
Anatoly has been fuzzing with kBdysch harness and reported a hang in one
of the outcomes:
0: R1=ctx(id=0,off=0,imm=0) R10=fp0
0: (85) call bpf_get_socket_cookie#46
1: R0_w=invP(id=0) R10=fp0
1: (57) r0 &= 808464432
2: R0_w=invP(id=0,umax_value=808464432,var_off=(0x0; 0x30303030)) R10=fp0
2: (14) w0 -= 810299440
3: R0_w=invP(id=0,umax_value=4294967295,var_off=(0xcf800000; 0x3077fff0)) R10=fp0
3: (c4) w0 s>>= 1
4: R0_w=invP(id=0,umin_value=1740636160,umax_value=2147221496,var_off=(0x67c00000; 0x183bfff8)) R10=fp0
4: (76) if w0 s>= 0x30303030 goto pc+216
221: R0_w=invP(id=0,umin_value=1740636160,umax_value=2147221496,var_off=(0x67c00000; 0x183bfff8)) R10=fp0
221: (95) exit
processed 6 insns (limit 1000000) [...]
Taking a closer look, the program was xlated as follows:
# ./bpftool p d x i 12
0: (85) call bpf_get_socket_cookie#7800896
1: (bf) r6 = r0
2: (57) r6 &= 808464432
3: (14) w6 -= 810299440
4: (c4) w6 s>>= 1
5: (76) if w6 s>= 0x30303030 goto pc+216
6: (05) goto pc-1
7: (05) goto pc-1
8: (05) goto pc-1
[...]
220: (05) goto pc-1
221: (05) goto pc-1
222: (95) exit
Meaning, the visible effect is very similar to f54c7898ed ("bpf: Fix
precision tracking for unbounded scalars"), that is, the fall-through
branch in the instruction 5 is considered to be never taken given the
conclusion from the min/max bounds tracking in w6, and therefore the
dead-code sanitation rewrites it as goto pc-1. However, real-life input
disagrees with verification analysis since a soft-lockup was observed.
The bug sits in the analysis of the ARSH. The definition is that we shift
the target register value right by K bits through shifting in copies of
its sign bit. In adjust_scalar_min_max_vals(), we do first coerce the
register into 32 bit mode, same happens after simulating the operation.
However, for the case of simulating the actual ARSH, we don't take the
mode into account and act as if it's always 64 bit, but location of sign
bit is different:
dst_reg->smin_value >>= umin_val;
dst_reg->smax_value >>= umin_val;
dst_reg->var_off = tnum_arshift(dst_reg->var_off, umin_val);
Consider an unknown R0 where bpf_get_socket_cookie() (or others) would
for example return 0xffff. With the above ARSH simulation, we'd see the
following results:
[...]
1: R1=ctx(id=0,off=0,imm=0) R2_w=invP65535 R10=fp0
1: (85) call bpf_get_socket_cookie#46
2: R0_w=invP(id=0) R10=fp0
2: (57) r0 &= 808464432
-> R0_runtime = 0x3030
3: R0_w=invP(id=0,umax_value=808464432,var_off=(0x0; 0x30303030)) R10=fp0
3: (14) w0 -= 810299440
-> R0_runtime = 0xcfb40000
4: R0_w=invP(id=0,umax_value=4294967295,var_off=(0xcf800000; 0x3077fff0)) R10=fp0
(0xffffffff)
4: (c4) w0 s>>= 1
-> R0_runtime = 0xe7da0000
5: R0_w=invP(id=0,umin_value=1740636160,umax_value=2147221496,var_off=(0x67c00000; 0x183bfff8)) R10=fp0
(0x67c00000) (0x7ffbfff8)
[...]
In insn 3, we have a runtime value of 0xcfb40000, which is '1100 1111 1011
0100 0000 0000 0000 0000', the result after the shift has 0xe7da0000 that
is '1110 0111 1101 1010 0000 0000 0000 0000', where the sign bit is correctly
retained in 32 bit mode. In insn4, the umax was 0xffffffff, and changed into
0x7ffbfff8 after the shift, that is, '0111 1111 1111 1011 1111 1111 1111 1000'
and means here that the simulation didn't retain the sign bit. With above
logic, the updates happen on the 64 bit min/max bounds and given we coerced
the register, the sign bits of the bounds are cleared as well, meaning, we
need to force the simulation into s32 space for 32 bit alu mode.
Verification after the fix below. We're first analyzing the fall-through branch
on 32 bit signed >= test eventually leading to rejection of the program in this
specific case:
0: R1=ctx(id=0,off=0,imm=0) R10=fp0
0: (b7) r2 = 808464432
1: R1=ctx(id=0,off=0,imm=0) R2_w=invP808464432 R10=fp0
1: (85) call bpf_get_socket_cookie#46
2: R0_w=invP(id=0) R10=fp0
2: (bf) r6 = r0
3: R0_w=invP(id=0) R6_w=invP(id=0) R10=fp0
3: (57) r6 &= 808464432
4: R0_w=invP(id=0) R6_w=invP(id=0,umax_value=808464432,var_off=(0x0; 0x30303030)) R10=fp0
4: (14) w6 -= 810299440
5: R0_w=invP(id=0) R6_w=invP(id=0,umax_value=4294967295,var_off=(0xcf800000; 0x3077fff0)) R10=fp0
5: (c4) w6 s>>= 1
6: R0_w=invP(id=0) R6_w=invP(id=0,umin_value=3888119808,umax_value=4294705144,var_off=(0xe7c00000; 0x183bfff8)) R10=fp0
(0x67c00000) (0xfffbfff8)
6: (76) if w6 s>= 0x30303030 goto pc+216
7: R0_w=invP(id=0) R6_w=invP(id=0,umin_value=3888119808,umax_value=4294705144,var_off=(0xe7c00000; 0x183bfff8)) R10=fp0
7: (30) r0 = *(u8 *)skb[808464432]
BPF_LD_[ABS|IND] uses reserved fields
processed 8 insns (limit 1000000) [...]
Fixes: 9cbe1f5a32 ("bpf/verifier: improve register value range tracking with ARSH")
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200115204733.16648-1-daniel@iogearbox.net
Suspend to IDLE invokes tick_unfreeze() on resume. tick_unfreeze() on the
first resuming CPU resumes timekeeping, which also has the side effect of
resetting the softlockup watchdog on this CPU.
But on the secondary CPUs the watchdog is not reset in the resume /
unfreeze() path, which can result in false softlockup warnings on those
CPUs depending on the time spent in suspend.
Prevent this by clearing the softlock watchdog in the unfreeze path also
on the secondary resuming CPUs.
[ tglx: Massaged changelog ]
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20200110083902.27276-1-chunyan.zhang@unisoc.com
Commit 8b401f9ed2 ("bpf: implement bpf_send_signal() helper")
added helper bpf_send_signal() which permits bpf program to
send a signal to the current process. The signal may be
delivered to any threads in the process.
We found a use case where sending the signal to the current
thread is more preferable.
- A bpf program will collect the stack trace and then
send signal to the user application.
- The user application will add some thread specific
information to the just collected stack trace for
later analysis.
If bpf_send_signal() is used, user application will need
to check whether the thread receiving the signal matches
the thread collecting the stack by checking thread id.
If not, it will need to send signal to another thread
through pthread_kill().
This patch proposed a new helper bpf_send_signal_thread(),
which sends the signal to the thread corresponding to
the current kernel task. This way, user space is guaranteed that
bpf_program execution context and user space signal handling
context are the same thread.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200115035002.602336-1-yhs@fb.com
The test_cgcore_no_internal_process_constraint_on_threads selftest when
running with subsystem controlling noise triggers two warnings:
> [ 597.443115] WARNING: CPU: 1 PID: 28167 at kernel/cgroup/cgroup.c:3131 cgroup_apply_control_enable+0xe0/0x3f0
> [ 597.443413] WARNING: CPU: 1 PID: 28167 at kernel/cgroup/cgroup.c:3177 cgroup_apply_control_disable+0xa6/0x160
Both stem from a call to cgroup_type_write. The first warning was also
triggered by syzkaller.
When we're switching cgroup to threaded mode shortly after a subsystem
was disabled on it, we can see the respective subsystem css dying there.
The warning in cgroup_apply_control_enable is harmless in this case
since we're not adding new subsys anyway.
The warning in cgroup_apply_control_disable indicates an attempt to kill
css of recently disabled subsystem repeatedly.
The commit prevents these situations by making cgroup_type_write wait
for all dying csses to go away before re-applying subtree controls.
When at it, the locations of WARN_ON_ONCE calls are moved so that
warning is triggered only when we are about to misuse the dying css.
Reported-by: syzbot+5493b2a54d31d6aea629@syzkaller.appspotmail.com
Reported-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
It's surprising that workqueue_execute_end includes only the work when
its counterpart workqueue_execute_start has both the work and the worker
function.
You can't set a tracing filter or trigger based on the function, and
postprocessing scripts interested in specific functions are harder to
write since they have to remember the work from _start and match it up
with the same field in _end.
Add the function name, taking care to use the copy stashed in the
worker since the work is no longer safe to touch.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Tejun Heo <tj@kernel.org>
Function name cgroup_rstat_cpu_pop_upated() in comment should be
cgroup_rstat_cpu_pop_updated().
Signed-off-by: Chen Zhou <chenzhou10@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
It is useful to know which module failed signature verification, so
print the module name along with the error message.
Signed-off-by: Jessica Yu <jeyu@kernel.org>
The alarmtimer_rtc_add_device() function creates a wakeup source and then
tries to grab a module reference. If that fails the function returns early
with an error code, but fails to remove the wakeup source.
Cleanup this exit path so there is no dangling wakeup source, which is
named 'alarmtime' left allocated which will conflict with another RTC
device that may be registered later.
Fixes: 51218298a2 ("alarmtimer: Ensure RTC module is not unloaded")
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200109155910.907-2-swboyd@chromium.org
With CONFIG_PROVE_RCU_LIST, I had many suspicious RCU warnings
when I ran ftracetest trigger testcases.
-----
# dmesg -c > /dev/null
# ./ftracetest test.d/trigger
...
# dmesg | grep "RCU-list traversed" | cut -f 2 -d ] | cut -f 2 -d " "
kernel/trace/trace_events_hist.c:6070
kernel/trace/trace_events_hist.c:1760
kernel/trace/trace_events_hist.c:5911
kernel/trace/trace_events_trigger.c:504
kernel/trace/trace_events_hist.c:1810
kernel/trace/trace_events_hist.c:3158
kernel/trace/trace_events_hist.c:3105
kernel/trace/trace_events_hist.c:5518
kernel/trace/trace_events_hist.c:5998
kernel/trace/trace_events_hist.c:6019
kernel/trace/trace_events_hist.c:6044
kernel/trace/trace_events_trigger.c:1500
kernel/trace/trace_events_trigger.c:1540
kernel/trace/trace_events_trigger.c:539
kernel/trace/trace_events_trigger.c:584
-----
I investigated those warnings and found that the RCU-list
traversals in event trigger and hist didn't need to use
RCU version because those were called only under event_mutex.
I also checked other RCU-list traversals related to event
trigger list, and found that most of them were called from
event_hist_trigger_func() or hist_unregister_trigger() or
register/unregister functions except for a few cases.
Replace these unneeded RCU-list traversals with normal list
traversal macro and lockdep_assert_held() to check the
event_mutex is held.
Link: http://lkml.kernel.org/r/157680910305.11685.15110237954275915782.stgit@devnote2
Cc: stable@vger.kernel.org
Fixes: 30350d65ac ("tracing: Add variable support to hist triggers")
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Also fixes a couple of typos
Link: http://lkml.kernel.org/r/1401992525-10417-1-git-send-email-fabf@skynet.be
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Fabian Frederick <fabf@skynet.be>
[ Found this deep in the abyss of my INBOX ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix double perf_event linking to trace_uprobe_filter on
multiple uprobe event by moving trace_uprobe_filter under
trace_probe_event.
In uprobe perf event, trace_uprobe_filter data structure is
managing target mm filters (in perf_event) related to each
uprobe event.
Since commit 60d53e2c3b ("tracing/probe: Split trace_event
related data from trace_probe") left the trace_uprobe_filter
data structure in trace_uprobe, if a trace_probe_event has
multiple trace_uprobe (multi-probe event), a perf_event is
added to different trace_uprobe_filter on each trace_uprobe.
This leads a linked list corruption.
To fix this issue, move trace_uprobe_filter to trace_probe_event
and link it once on each event instead of each probe.
Link: http://lkml.kernel.org/r/157862073931.1800.3800576241181489174.stgit@devnote2
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: "Naveen N . Rao" <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: "David S . Miller" <davem@davemloft.net>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: =?utf-8?q?Toke_H=C3=B8iland-J?= =?utf-8?b?w7hyZ2Vuc2Vu?= <thoiland@redhat.com>
Cc: Jean-Tsung Hsiao <jhsiao@redhat.com>
Cc: Jesper Dangaard Brouer <brouer@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 60d53e2c3b ("tracing/probe: Split trace_event related data from trace_probe")
Link: https://lkml.kernel.org/r/20200108171611.GA8472@kernel.org
Reported-by: Arnaldo Carvalho de Melo <acme@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Merge misc fixes from David Howells.
Two afs fixes and a key refcounting fix.
* dhowells:
afs: Fix afs_lookup() to not clobber the version on a new dentry
afs: Fix use-after-loss-of-ref
keys: Fix request_key() cache
Instead of using bpf_struct_ops_map_lookup_elem() which is
not implemented, bpf_struct_ops_map_seq_show_elem() should
also use bpf_struct_ops_map_sys_lookup_elem() which does
an inplace update to the value. The change allocates
a value to pass to bpf_struct_ops_map_sys_lookup_elem().
[root@arch-fb-vm1 bpf]# cat /sys/fs/bpf/dctcp
{{{1}},BPF_STRUCT_OPS_STATE_INUSE,{{00000000df93eebc,00000000df93eebc},0,2, ...
Fixes: 85d33df357 ("bpf: Introduce BPF_MAP_TYPE_STRUCT_OPS")
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200114072647.3188298-1-kafai@fb.com
When the key cached by request_key() and co. is cleaned up on exit(),
the code looks in the wrong task_struct, and so clears the wrong cache.
This leads to anomalies in key refcounting when doing, say, a kernel
build on an afs volume, that then trigger kasan to report a
use-after-free when the key is viewed in /proc/keys.
Fix this by making exit_creds() look in the passed-in task_struct rather
than in current (the task_struct cleanup code is deferred by RCU and
potentially run in another task).
Fixes: 7743c48e54 ("keys: Cache result of request_key*() temporarily in task_struct")
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The name mmu_notifier_mm implies that the thing is a mm_struct pointer,
and is difficult to abbreviate. The struct is actually holding the
interval tree and hlist containing the notifiers subscribed to a mm.
Use 'subscriptions' as the variable name for this struct instead of the
really terrible and misleading 'mmn_mm'.
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
API to set time namespace offsets for children processes, i.e.:
echo "$clockid $offset_sec $offset_nsec" > /proc/self/timens_offsets
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-28-dima@arista.com
The VVAR page layout depends on whether a task belongs to the root or
non-root time namespace. Whenever a task changes its namespace, the VVAR
page tables are cleared and then they will be re-faulted with a
corresponding layout.
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-27-dima@arista.com
VDSO support for Time namespace needs to set up a page with the same
layout as VVAR. That timens page will be placed on position of VVAR page
inside namespace. That page contains time namespace clock offsets and it
has vdso_data->seq set to 1 to enforce the slow path and
vdso_data->clock_mode set to VCLOCK_TIMENS to enforce the time namespace
handling path.
Allocate the timens page during namespace creation. Setup the offsets
when the first task enters the ns and freeze them to guarantee the pace
of monotonic/boottime clocks and to avoid breakage of applications.
The design decision is to have a global offset_lock which is used during
namespace offsets setup and to freeze offsets when the first task joins the
new time namespace. That is better in terms of memory usage compared to
having a per namespace mutex that's used only during the setup period.
Suggested-by: Andy Lutomirski <luto@kernel.org>
Based-on-work-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-24-dima@arista.com
clock_nanosleep() accepts absolute values of expiration time, if the
TIMER_ABSTIME flag is set. This value is in the tasks time namespace,
which has to be converted to the host time namespace.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-18-dima@arista.com
clock_nanosleep() accepts absolute values of expiration time when
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace, and has to be converted to the host's time.
There is timens_ktime_to_host() helper for converting time, but
it accepts ktime argument.
As a preparation, make hrtimer_nanosleep() accept a clock value in ktime
instead of timespec64.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-17-dima@arista.com
clock_nanosleep() accepts absolute values of expiration time when the
TIMER_ABSTIME flag is set. This absolute value is inside the task's
time namespace and has to be converted to the host's time.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-16-dima@arista.com
Wire timer_settime() syscall into time namespace virtualization.
sys_timer_settime() calls the ktime->timer_set() callback. Right now,
common_timer_set() is the only implementation for the callback.
The user-supplied expiry value is converted from timespec64 to ktime and
then timens_ktime_to_host() can be used to convert namespace's time to the
host time.
Inside a time namespace kernel's time differs by a fixed offset from a
user-supplied time, but only absolute values (TIMER_ABSTIME) must be
converted.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-15-dima@arista.com
The helper subtracts namespace's clock offset from the given time
and ensures that the result is within [0, KTIME_MAX].
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-13-dima@arista.com
Adjust monotonic and boottime clocks with per-timens offsets. As the
result a process inside time namespace will see timers and clocks corrected
to offsets that were set when the namespace was created
Note that applications usually go through vDSO to get time, which is not
yet adjusted. Further changes will complete time namespace virtualisation
with vDSO support.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-12-dima@arista.com
Now, when the clock_get_ktime() callback exists, the suboptimal
timespec64-based conversion can be removed from common_timer_get().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-11-dima@arista.com
The callsite in common_timer_get() has already a comment:
/*
* The timespec64 based conversion is suboptimal, but it's not
* worth to implement yet another callback.
*/
kc->clock_get(timr->it_clock, &ts64);
now = timespec64_to_ktime(ts64);
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-10-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
Wire up alarm bases with get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-9-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a tasks time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
struct alarm_base needs to follow the same naming convention, so rename
.gettime() callback into get_ktime() as a preparation for introducing
get_timespec().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-8-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format in (struct k_clock).
As a preparation ground for introducing clock_get_ktime(), the original
callback clock_get() was renamed into clock_get_timespec().
Reflect the renaming into the callback implementations.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-7-dima@arista.com
The upcoming support for time namespaces requires to have access to:
- The time in a task's time namespace for sys_clock_gettime()
- The time in the root name space for common_timer_get()
That adds a valid reason to finally implement a separate callback which
returns the time in ktime_t format, rather than in (struct timespec).
Rename the clock_get() callback to clock_get_timespec() as a preparation
for introducing clock_get_ktime().
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-6-dima@arista.com
Introduce offsets for time namespace. They will contain an adjustment
needed to convert clocks to/from host's.
A new namespace is created with the same offsets as the time namespace
of the current process.
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@openvz.org>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191112012724.250792-5-dima@arista.com
Time Namespace isolates clock values.
The kernel provides access to several clocks CLOCK_REALTIME,
CLOCK_MONOTONIC, CLOCK_BOOTTIME, etc.
CLOCK_REALTIME
System-wide clock that measures real (i.e., wall-clock) time.
CLOCK_MONOTONIC
Clock that cannot be set and represents monotonic time since
some unspecified starting point.
CLOCK_BOOTTIME
Identical to CLOCK_MONOTONIC, except it also includes any time
that the system is suspended.
For many users, the time namespace means the ability to changes date and
time in a container (CLOCK_REALTIME). Providing per namespace notions of
CLOCK_REALTIME would be complex with a massive overhead, but has a dubious
value.
But in the context of checkpoint/restore functionality, monotonic and
boottime clocks become interesting. Both clocks are monotonic with
unspecified starting points. These clocks are widely used to measure time
slices and set timers. After restoring or migrating processes, it has to be
guaranteed that they never go backward. In an ideal case, the behavior of
these clocks should be the same as for a case when a whole system is
suspended. All this means that it is required to set CLOCK_MONOTONIC and
CLOCK_BOOTTIME clocks, which can be achieved by adding per-namespace
offsets for clocks.
A time namespace is similar to a pid namespace in the way how it is
created: unshare(CLONE_NEWTIME) system call creates a new time namespace,
but doesn't set it to the current process. Then all children of the process
will be born in the new time namespace, or a process can use the setns()
system call to join a namespace.
This scheme allows setting clock offsets for a namespace, before any
processes appear in it.
All available clone flags have been used, so CLONE_NEWTIME uses the highest
bit of CSIGNAL. It means that it can be used only with the unshare() and
the clone3() system calls.
[ tglx: Adjusted paragraph about clone3() to reality and massaged the
changelog a bit. ]
Co-developed-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Andrei Vagin <avagin@gmail.com>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://criu.org/Time_namespace
Link: https://lists.openvz.org/pipermail/criu/2018-June/041504.html
Link: https://lore.kernel.org/r/20191112012724.250792-4-dima@arista.com
With CONFIG_PROVE_RCU_LIST, I had many suspicious RCU warnings
when I ran ftracetest trigger testcases.
-----
# dmesg -c > /dev/null
# ./ftracetest test.d/trigger
...
# dmesg | grep "RCU-list traversed" | cut -f 2 -d ] | cut -f 2 -d " "
kernel/trace/trace_events_hist.c:6070
kernel/trace/trace_events_hist.c:1760
kernel/trace/trace_events_hist.c:5911
kernel/trace/trace_events_trigger.c:504
kernel/trace/trace_events_hist.c:1810
kernel/trace/trace_events_hist.c:3158
kernel/trace/trace_events_hist.c:3105
kernel/trace/trace_events_hist.c:5518
kernel/trace/trace_events_hist.c:5998
kernel/trace/trace_events_hist.c:6019
kernel/trace/trace_events_hist.c:6044
kernel/trace/trace_events_trigger.c:1500
kernel/trace/trace_events_trigger.c:1540
kernel/trace/trace_events_trigger.c:539
kernel/trace/trace_events_trigger.c:584
-----
I investigated those warnings and found that the RCU-list
traversals in event trigger and hist didn't need to use
RCU version because those were called only under event_mutex.
I also checked other RCU-list traversals related to event
trigger list, and found that most of them were called from
event_hist_trigger_func() or hist_unregister_trigger() or
register/unregister functions except for a few cases.
Replace these unneeded RCU-list traversals with normal list
traversal macro and lockdep_assert_held() to check the
event_mutex is held.
Link: http://lkml.kernel.org/r/157680910305.11685.15110237954275915782.stgit@devnote2
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This syscall allows for the retrieval of file descriptors from other
processes, based on their pidfd. This is possible using ptrace, and
injection of parasitic code to inject code which leverages SCM_RIGHTS
to move file descriptors between a tracee and a tracer. Unfortunately,
ptrace comes with a high cost of requiring the process to be stopped,
and breaks debuggers. This does not require stopping the process under
manipulation.
One reason to use this is to allow sandboxers to take actions on file
descriptors on the behalf of another process. For example, this can be
combined with seccomp-bpf's user notification to do on-demand fd
extraction and take privileged actions. One such privileged action
is binding a socket to a privileged port.
/* prototype */
/* flags is currently reserved and should be set to 0 */
int sys_pidfd_getfd(int pidfd, int fd, unsigned int flags);
/* testing */
Ran self-test suite on x86_64
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Link: https://lore.kernel.org/r/20200107175927.4558-3-sargun@sargun.me
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Add below function-tracer filter options to boot-time tracing.
- ftrace.[instance.INSTANCE.]ftrace.filters
This will take an array of tracing function filter rules
- ftrace.[instance.INSTANCE.]ftrace.notraces
This will take an array of NON-tracing function filter rules
Link: http://lkml.kernel.org/r/157867244841.17873.10933616628243103561.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add ftrace.cpumask option support to boot-time tracing.
This sets cpumask for each instance.
- ftrace.[instance.INSTANCE.]cpumask = CPUMASK;
Set the trace cpumask. Note that the CPUMASK should be a string
which <tracefs>/tracing_cpumask can accepts.
Link: http://lkml.kernel.org/r/157867243625.17873.13613922641273149372.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add instance node support to boot-time tracing. User can set
some options and event nodes under instance node.
- ftrace.instance.INSTANCE[...]
Add new INSTANCE instance. Some options and event nodes
are acceptable for instance node.
Link: http://lkml.kernel.org/r/157867242413.17873.9814204526141500278.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add synthetic event node support to boot time tracing.
The synthetic event is a kind of event node, but the group
name is "synthetic".
- ftrace.event.synthetic.EVENT.fields = FIELD[, FIELD2...]
Defines new synthetic event with FIELDs. Each field should be
"type varname".
The synthetic node requires "fields" string arraies, which defines
the fields as same as tracing/synth_events interface.
Link: http://lkml.kernel.org/r/157867241236.17873.12411615143321557709.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add kprobe event support on event node to boot-time tracing.
If the group name of event is "kprobes", the boot-time tracing
defines new probe event according to "probes" values.
- ftrace.event.kprobes.EVENT.probes = PROBE[, PROBE2...]
Defines new kprobe event based on PROBEs. It is able to define
multiple probes on one event, but those must have same type of
arguments.
For example,
ftrace.events.kprobes.myevent {
probes = "vfs_read $arg1 $arg2";
enable;
}
This will add kprobes:myevent on vfs_read with the 1st and the 2nd
arguments.
Link: http://lkml.kernel.org/r/157867240104.17873.9712052065426433111.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add per-event settings for boottime tracing. User can set filter,
actions and enable on each event on boot. The event entries are
under ftrace.event.GROUP.EVENT node (note that the option key
includes event's group name and event name.) This supports below
configs.
- ftrace.event.GROUP.EVENT.enable
Enables GROUP:EVENT tracing.
- ftrace.event.GROUP.EVENT.filter = FILTER
Set FILTER rule to the GROUP:EVENT.
- ftrace.event.GROUP.EVENT.actions = ACTION[, ACTION2...]
Set ACTIONs to the GROUP:EVENT.
For example,
ftrace.event.sched.sched_process_exec {
filter = "pid < 128"
enable
}
this will enable tracing "sched:sched_process_exec" event
with "pid < 128" filter.
Link: http://lkml.kernel.org/r/157867238942.17873.11177628789184546198.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Setup tracing options via extra boot config in addition to kernel
command line.
This adds following commands support. These are applied to
the global trace instance.
- ftrace.options = OPT1[,OPT2...]
Enable given ftrace options.
- ftrace.trace_clock = CLOCK
Set given CLOCK to ftrace's trace_clock.
- ftrace.buffer_size = SIZE
Configure ftrace buffer size to SIZE. You can use "KB" or "MB"
for that SIZE.
- ftrace.events = EVENT[, EVENT2...]
Enable given events on boot. You can use a wild card in EVENT.
- ftrace.tracer = TRACER
Set TRACER to current tracer on boot. (e.g. function)
Note that this is NOT replacing the kernel parameters, because
this boot config based setting is later than that. If you want to
trace earlier boot events, you still need kernel parameters.
Link: http://lkml.kernel.org/r/157867237723.17873.17494943526320587488.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Make the synthetic event accepts a different type field to record.
However, the size and signed flag must be same.
Link: http://lkml.kernel.org/r/157867235358.17873.61732996461602171.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Register kprobe event to dynevent in subsys_initcall level.
This will allow kernel to register new kprobe events in
fs_initcall level via trace_run_command.
Link: http://lkml.kernel.org/r/157867234213.17873.18039000024374948737.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since kprobe-events use event_trigger_unlock_commit_regs() directly,
that events doesn't show up in printk buffer if "tp_printk" is set.
Use trace_event_buffer_commit() in kprobe events so that it can
invoke output_printk() as same as other trace events.
Link: http://lkml.kernel.org/r/157867233085.17873.5210928676787339604.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
[ Adjusted data var declaration placement in __kretprobe_trace_func() ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Apply soft-disabled and the filter rule of the trace events to
the printk output of tracepoints (a.k.a. tp_printk kernel parameter)
as same as trace buffer output.
Link: http://lkml.kernel.org/r/157867231876.17873.15825819592284704068.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As there's two struct ring_buffers in the kernel, it causes some confusion.
The other one being the perf ring buffer. It was agreed upon that as neither
of the ring buffers are generic enough to be used globally, they should be
renamed as:
perf's ring_buffer -> perf_buffer
ftrace's ring_buffer -> trace_buffer
This implements the changes to the ring buffer that ftrace uses.
Link: https://lore.kernel.org/r/20191213140531.116b3200@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As we are working to remove the generic "ring_buffer" name that is used by
both tracing and perf, the ring_buffer name for tracing will be renamed to
trace_buffer, and perf's ring buffer will be renamed to perf_buffer.
As there already exists a trace_buffer that is used by the trace_arrays, it
needs to be first renamed to array_buffer.
Link: https://lore.kernel.org/r/20191213153553.GE20583@krava
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
eBPF requires needing to know the size of the perf ring buffer structure.
But it unfortunately has the same name as the generic ring buffer used by
tracing and oprofile. To make it less ambiguous, rename the perf ring buffer
structure to "perf_buffer".
As other parts of the ring buffer code has "perf_" as the prefix, it only
makes sense to give the ring buffer the "perf_" prefix as well.
Link: https://lore.kernel.org/r/20191213153553.GE20583@krava
Acked-by: Peter Zijlstra <peterz@infradead.org>
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXhhtDQAKCRCRxhvAZXjc
orQ3AQD7H2ovZbPIpWbwOnRIExBF4O8gPDfFc/J/RweZx40v/AD/QwfFnq0TpmUc
UfS4zzLxJ4K+L4RYWId5v8MFHGIu8QQ=
=LmmJ
-----END PGP SIGNATURE-----
Merge tag 'clone3-tls-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread fixes from Christian Brauner:
"This contains a series of patches to fix CLONE_SETTLS when used with
clone3().
The clone3() syscall passes the tls argument through struct clone_args
instead of a register. This means, all architectures that do not
implement copy_thread_tls() but still support CLONE_SETTLS via
copy_thread() expecting the tls to be located in a register argument
based on clone() are currently unfortunately broken. Their tls value
will be garbage.
The patch series fixes this on all architectures that currently define
__ARCH_WANT_SYS_CLONE3. It also adds a compile-time check to ensure
that any architecture that enables clone3() in the future is forced to
also implement copy_thread_tls().
My ultimate goal is to get rid of the copy_thread()/copy_thread_tls()
split and just have copy_thread_tls() at some point in the not too
distant future (Maybe even renaming copy_thread_tls() back to simply
copy_thread() once the old function is ripped from all arches). This
is dependent now on all arches supporting clone3().
While all relevant arches do that now there are still four missing:
ia64, m68k, sh and sparc. They have the system call reserved, but not
implemented. Once they all implement clone3() we can get rid of
ARCH_WANT_SYS_CLONE3 and HAVE_COPY_THREAD_TLS.
This series also includes a minor fix for the arm64 uapi headers which
caused __NR_clone3 to be missing from the exported user headers.
Unfortunately the series came in a little late especially given that
it touches a range of architectures. Due to the holidays not all arch
maintainers responded in time probably due to their backlog. Will and
Arnd have thankfully acked the arm specific changes.
Given that the changes are straightforward and rather minimal combined
with the fact the that clone3() with CLONE_SETTLS is broken I decided
to send them post rc3 nonetheless"
* tag 'clone3-tls-v5.5-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
um: Implement copy_thread_tls
clone3: ensure copy_thread_tls is implemented
xtensa: Implement copy_thread_tls
riscv: Implement copy_thread_tls
parisc: Implement copy_thread_tls
arm: Implement copy_thread_tls
arm64: Implement copy_thread_tls
arm64: Move __ARCH_WANT_SYS_CLONE3 definition to uapi headers
New llvm and old llvm with libbpf help produce BTF that distinguish global and
static functions. Unlike arguments of static function the arguments of global
functions cannot be removed or optimized away by llvm. The compiler has to use
exactly the arguments specified in a function prototype. The argument type
information allows the verifier validate each global function independently.
For now only supported argument types are pointer to context and scalars. In
the future pointers to structures, sizes, pointer to packet data can be
supported as well. Consider the following example:
static int f1(int ...)
{
...
}
int f3(int b);
int f2(int a)
{
f1(a) + f3(a);
}
int f3(int b)
{
...
}
int main(...)
{
f1(...) + f2(...) + f3(...);
}
The verifier will start its safety checks from the first global function f2().
It will recursively descend into f1() because it's static. Then it will check
that arguments match for the f3() invocation inside f2(). It will not descend
into f3(). It will finish f2() that has to be successfully verified for all
possible values of 'a'. Then it will proceed with f3(). That function also has
to be safe for all possible values of 'b'. Then it will start subprog 0 (which
is main() function). It will recursively descend into f1() and will skip full
check of f2() and f3(), since they are global. The order of processing global
functions doesn't affect safety, since all global functions must be proven safe
based on their arguments only.
Such function by function verification can drastically improve speed of the
verification and reduce complexity.
Note that the stack limit of 512 still applies to the call chain regardless whether
functions were static or global. The nested level of 8 also still applies. The
same recursion prevention checks are in place as well.
The type information and static/global kind is preserved after the verification
hence in the above example global function f2() and f3() can be replaced later
by equivalent functions with the same types that are loaded and verified later
without affecting safety of this main() program. Such replacement (re-linking)
of global functions is a subject of future patches.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200110064124.1760511-3-ast@kernel.org
There is a spelling mistake in a pr_info message. Fix it.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
As tests are added to kunit, it will become less feasible to execute
all built tests together. By supporting modular tests we provide
a simple way to do selective execution on a running system; specifying
CONFIG_KUNIT=y
CONFIG_KUNIT_EXAMPLE_TEST=m
...means we can simply "insmod example-test.ko" to run the tests.
To achieve this we need to do the following:
o export the required symbols in kunit
o string-stream tests utilize non-exported symbols so for now we skip
building them when CONFIG_KUNIT_TEST=m.
o drivers/base/power/qos-test.c contains a few unexported interface
references, namely freq_qos_read_value() and freq_constraints_init().
Both of these could be potentially defined as static inline functions
in include/linux/pm_qos.h, but for now we simply avoid supporting
module build for that test suite.
o support a new way of declaring test suites. Because a module cannot
do multiple late_initcall()s, we provide a kunit_test_suites() macro
to declare multiple suites within the same module at once.
o some test module names would have been too general ("test-test"
and "example-test" for kunit tests, "inode-test" for ext4 tests);
rename these as appropriate ("kunit-test", "kunit-example-test"
and "ext4-inode-test" respectively).
Also define kunit_test_suite() via kunit_test_suites()
as callers in other trees may need the old definition.
Co-developed-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Knut Omang <knut.omang@oracle.com>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Reviewed-by: Brendan Higgins <brendanhiggins@google.com>
Acked-by: Theodore Ts'o <tytso@mit.edu> # for ext4 bits
Acked-by: David Gow <davidgow@google.com> # For list-test
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
The ungrafting from PRIO bug fixes in net, when merged into net-next,
merge cleanly but create a build failure. The resolution used here is
from Petr Machata.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) Missing netns pointer init in arp_tables, from Florian Westphal.
2) Fix normal tcp SACK being treated as D-SACK, from Pengcheng Yang.
3) Fix divide by zero in sch_cake, from Wen Yang.
4) Len passed to skb_put_padto() is wrong in qrtr code, from Carl
Huang.
5) cmd->obj.chunk is leaked in sctp code error paths, from Xin Long.
6) cgroup bpf programs can be released out of order, fix from Roman
Gushchin.
7) Make sure stmmac debugfs entry name is changed when device name
changes, from Jiping Ma.
8) Fix memory leak in vlan_dev_set_egress_priority(), from Eric
Dumazet.
9) SKB leak in lan78xx usb driver, also from Eric Dumazet.
10) Ridiculous TCA_FQ_QUANTUM values configured can cause loops in fq
packet scheduler, reject them. From Eric Dumazet.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (69 commits)
tipc: fix wrong connect() return code
tipc: fix link overflow issue at socket shutdown
netfilter: ipset: avoid null deref when IPSET_ATTR_LINENO is present
netfilter: conntrack: dccp, sctp: handle null timeout argument
atm: eni: fix uninitialized variable warning
macvlan: do not assume mac_header is set in macvlan_broadcast()
net: sch_prio: When ungrafting, replace with FIFO
mlxsw: spectrum_qdisc: Ignore grafting of invisible FIFO
MAINTAINERS: Remove myself as co-maintainer for qcom-ethqos
gtp: fix bad unlock balance in gtp_encap_enable_socket
pkt_sched: fq: do not accept silly TCA_FQ_QUANTUM
tipc: remove meaningless assignment in Makefile
tipc: do not add socket.o to tipc-y twice
net: stmmac: dwmac-sun8i: Allow all RGMII modes
net: stmmac: dwmac-sunxi: Allow all RGMII modes
net: usb: lan78xx: fix possible skb leak
net: stmmac: Fixed link does not need MDIO Bus
vlan: vlan_changelink() should propagate errors
vlan: fix memory leak in vlan_dev_set_egress_priority
stmmac: debugfs entry name is not be changed when udev rename device name.
...
Instead of issueing a warning if sched_clock_register() is called from a
context where IRQs are enabled, the code now ensures that IRQs are indeed
disabled.
Signed-off-by: Paul Cercueil <paul@crapouillou.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20200107010630.954648-1-paul@crapouillou.net
Using compat_sys_getitimer and compat_sys_setitimer on alpha
causes a link failure in the Alpha tinyconfig and other configurations
that turn off CONFIG_POSIX_TIMERS.
Use the same #ifdef check for the stub version as well.
Fixes: 4c22ea2b91 ("y2038: use compat_{get,set}_itimer on alpha")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Link: https://lore.kernel.org/r/20191207191043.656328-1-arnd@arndb.de
This patch makes "struct tcp_congestion_ops" to be the first user
of BPF STRUCT_OPS. It allows implementing a tcp_congestion_ops
in bpf.
The BPF implemented tcp_congestion_ops can be used like
regular kernel tcp-cc through sysctl and setsockopt. e.g.
[root@arch-fb-vm1 bpf]# sysctl -a | egrep congestion
net.ipv4.tcp_allowed_congestion_control = reno cubic bpf_cubic
net.ipv4.tcp_available_congestion_control = reno bic cubic bpf_cubic
net.ipv4.tcp_congestion_control = bpf_cubic
There has been attempt to move the TCP CC to the user space
(e.g. CCP in TCP). The common arguments are faster turn around,
get away from long-tail kernel versions in production...etc,
which are legit points.
BPF has been the continuous effort to join both kernel and
userspace upsides together (e.g. XDP to gain the performance
advantage without bypassing the kernel). The recent BPF
advancements (in particular BTF-aware verifier, BPF trampoline,
BPF CO-RE...) made implementing kernel struct ops (e.g. tcp cc)
possible in BPF. It allows a faster turnaround for testing algorithm
in the production while leveraging the existing (and continue growing)
BPF feature/framework instead of building one specifically for
userspace TCP CC.
This patch allows write access to a few fields in tcp-sock
(in bpf_tcp_ca_btf_struct_access()).
The optional "get_info" is unsupported now. It can be added
later. One possible way is to output the info with a btf-id
to describe the content.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003508.3856115-1-kafai@fb.com
The patch introduces BPF_MAP_TYPE_STRUCT_OPS. The map value
is a kernel struct with its func ptr implemented in bpf prog.
This new map is the interface to register/unregister/introspect
a bpf implemented kernel struct.
The kernel struct is actually embedded inside another new struct
(or called the "value" struct in the code). For example,
"struct tcp_congestion_ops" is embbeded in:
struct bpf_struct_ops_tcp_congestion_ops {
refcount_t refcnt;
enum bpf_struct_ops_state state;
struct tcp_congestion_ops data; /* <-- kernel subsystem struct here */
}
The map value is "struct bpf_struct_ops_tcp_congestion_ops".
The "bpftool map dump" will then be able to show the
state ("inuse"/"tobefree") and the number of subsystem's refcnt (e.g.
number of tcp_sock in the tcp_congestion_ops case). This "value" struct
is created automatically by a macro. Having a separate "value" struct
will also make extending "struct bpf_struct_ops_XYZ" easier (e.g. adding
"void (*init)(void)" to "struct bpf_struct_ops_XYZ" to do some
initialization works before registering the struct_ops to the kernel
subsystem). The libbpf will take care of finding and populating the
"struct bpf_struct_ops_XYZ" from "struct XYZ".
Register a struct_ops to a kernel subsystem:
1. Load all needed BPF_PROG_TYPE_STRUCT_OPS prog(s)
2. Create a BPF_MAP_TYPE_STRUCT_OPS with attr->btf_vmlinux_value_type_id
set to the btf id "struct bpf_struct_ops_tcp_congestion_ops" of the
running kernel.
Instead of reusing the attr->btf_value_type_id,
btf_vmlinux_value_type_id s added such that attr->btf_fd can still be
used as the "user" btf which could store other useful sysadmin/debug
info that may be introduced in the furture,
e.g. creation-date/compiler-details/map-creator...etc.
3. Create a "struct bpf_struct_ops_tcp_congestion_ops" object as described
in the running kernel btf. Populate the value of this object.
The function ptr should be populated with the prog fds.
4. Call BPF_MAP_UPDATE with the object created in (3) as
the map value. The key is always "0".
During BPF_MAP_UPDATE, the code that saves the kernel-func-ptr's
args as an array of u64 is generated. BPF_MAP_UPDATE also allows
the specific struct_ops to do some final checks in "st_ops->init_member()"
(e.g. ensure all mandatory func ptrs are implemented).
If everything looks good, it will register this kernel struct
to the kernel subsystem. The map will not allow further update
from this point.
Unregister a struct_ops from the kernel subsystem:
BPF_MAP_DELETE with key "0".
Introspect a struct_ops:
BPF_MAP_LOOKUP_ELEM with key "0". The map value returned will
have the prog _id_ populated as the func ptr.
The map value state (enum bpf_struct_ops_state) will transit from:
INIT (map created) =>
INUSE (map updated, i.e. reg) =>
TOBEFREE (map value deleted, i.e. unreg)
The kernel subsystem needs to call bpf_struct_ops_get() and
bpf_struct_ops_put() to manage the "refcnt" in the
"struct bpf_struct_ops_XYZ". This patch uses a separate refcnt
for the purose of tracking the subsystem usage. Another approach
is to reuse the map->refcnt and then "show" (i.e. during map_lookup)
the subsystem's usage by doing map->refcnt - map->usercnt to filter out
the map-fd/pinned-map usage. However, that will also tie down the
future semantics of map->refcnt and map->usercnt.
The very first subsystem's refcnt (during reg()) holds one
count to map->refcnt. When the very last subsystem's refcnt
is gone, it will also release the map->refcnt. All bpf_prog will be
freed when the map->refcnt reaches 0 (i.e. during map_free()).
Here is how the bpftool map command will look like:
[root@arch-fb-vm1 bpf]# bpftool map show
6: struct_ops name dctcp flags 0x0
key 4B value 256B max_entries 1 memlock 4096B
btf_id 6
[root@arch-fb-vm1 bpf]# bpftool map dump id 6
[{
"value": {
"refcnt": {
"refs": {
"counter": 1
}
},
"state": 1,
"data": {
"list": {
"next": 0,
"prev": 0
},
"key": 0,
"flags": 2,
"init": 24,
"release": 0,
"ssthresh": 25,
"cong_avoid": 30,
"set_state": 27,
"cwnd_event": 28,
"in_ack_event": 26,
"undo_cwnd": 29,
"pkts_acked": 0,
"min_tso_segs": 0,
"sndbuf_expand": 0,
"cong_control": 0,
"get_info": 0,
"name": [98,112,102,95,100,99,116,99,112,0,0,0,0,0,0,0
],
"owner": 0
}
}
}
]
Misc Notes:
* bpf_struct_ops_map_sys_lookup_elem() is added for syscall lookup.
It does an inplace update on "*value" instead returning a pointer
to syscall.c. Otherwise, it needs a separate copy of "zero" value
for the BPF_STRUCT_OPS_STATE_INIT to avoid races.
* The bpf_struct_ops_map_delete_elem() is also called without
preempt_disable() from map_delete_elem(). It is because
the "->unreg()" may requires sleepable context, e.g.
the "tcp_unregister_congestion_control()".
* "const" is added to some of the existing "struct btf_func_model *"
function arg to avoid a compiler warning caused by this patch.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003505.3855919-1-kafai@fb.com
This patch allows the kernel's struct ops (i.e. func ptr) to be
implemented in BPF. The first use case in this series is the
"struct tcp_congestion_ops" which will be introduced in a
latter patch.
This patch introduces a new prog type BPF_PROG_TYPE_STRUCT_OPS.
The BPF_PROG_TYPE_STRUCT_OPS prog is verified against a particular
func ptr of a kernel struct. The attr->attach_btf_id is the btf id
of a kernel struct. The attr->expected_attach_type is the member
"index" of that kernel struct. The first member of a struct starts
with member index 0. That will avoid ambiguity when a kernel struct
has multiple func ptrs with the same func signature.
For example, a BPF_PROG_TYPE_STRUCT_OPS prog is written
to implement the "init" func ptr of the "struct tcp_congestion_ops".
The attr->attach_btf_id is the btf id of the "struct tcp_congestion_ops"
of the _running_ kernel. The attr->expected_attach_type is 3.
The ctx of BPF_PROG_TYPE_STRUCT_OPS is an array of u64 args saved
by arch_prepare_bpf_trampoline that will be done in the next
patch when introducing BPF_MAP_TYPE_STRUCT_OPS.
"struct bpf_struct_ops" is introduced as a common interface for the kernel
struct that supports BPF_PROG_TYPE_STRUCT_OPS prog. The supporting kernel
struct will need to implement an instance of the "struct bpf_struct_ops".
The supporting kernel struct also needs to implement a bpf_verifier_ops.
During BPF_PROG_LOAD, bpf_struct_ops_find() will find the right
bpf_verifier_ops by searching the attr->attach_btf_id.
A new "btf_struct_access" is also added to the bpf_verifier_ops such
that the supporting kernel struct can optionally provide its own specific
check on accessing the func arg (e.g. provide limited write access).
After btf_vmlinux is parsed, the new bpf_struct_ops_init() is called
to initialize some values (e.g. the btf id of the supporting kernel
struct) and it can only be done once the btf_vmlinux is available.
The R0 checks at BPF_EXIT is excluded for the BPF_PROG_TYPE_STRUCT_OPS prog
if the return type of the prog->aux->attach_func_proto is "void".
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003503.3855825-1-kafai@fb.com
This patch allows bitfield access as a scalar.
It checks "off + size > t->size" to avoid accessing bitfield
end up accessing beyond the struct. This check is done
outside of the loop since it is applicable to all access.
It also takes this chance to break early on the "off < moff" case.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003501.3855427-1-kafai@fb.com
It allows bpf prog (e.g. tracing) to attach
to a kernel function that takes enum argument.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003459.3855366-1-kafai@fb.com
info->btf_id expects the btf_id of a struct, so it should
store the final result after skipping modifiers (if any).
It also takes this chanace to add a missing newline in one of the
bpf_log() messages.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003456.3855176-1-kafai@fb.com
This patch makes the verifier save the PTR_TO_BTF_ID register state when
spilling to the stack.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200109003454.3854870-1-kafai@fb.com
When CONFIG_SYSFS is disabled, but CONFIG_HOTPLUG_SMT is enabled,
the kernel fails to link:
arch/x86/power/cpu.o: In function `hibernate_resume_nonboot_cpu_disable':
(.text+0x38d): undefined reference to `cpuhp_smt_enable'
arch/x86/power/hibernate.o: In function `arch_resume_nosmt':
hibernate.c:(.text+0x291): undefined reference to `cpuhp_smt_enable'
hibernate.c:(.text+0x29c): undefined reference to `cpuhp_smt_disable'
Move the exported functions out of the #ifdef section into its
own with the correct conditions.
The patch that caused this is marked for stable backports, so
this one may need to be backported as well.
Fixes: ec527c3180 ("x86/power: Fix 'nosmt' vs hibernation triple fault during resume")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Jiri Kosina <jkosina@suse.cz>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191210195614.786555-1-arnd@arndb.de
Requesting a threaded IRQ with handler=NULL and !ONESHOT fails, but the
error message does not include the IRQ line name, which makes it harder to
find the offending driver.
Print the IRQ line name to clarify where the error comes from. Use the same
format as the other pr_err() above in the same function.
Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20191105140854.27893-1-luca@lucaceresoli.net
Fix a kernel-doc warning in kernel/futex.c by adding notation
for @ret.
../kernel/futex.c:1187: warning: Function parameter or member 'ret' not described in 'wait_for_owner_exiting'
Fixes: 3ef240eaff ("futex: Prevent exit livelock")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/223be78c-f3c8-52df-836d-c5fb8e7907e9@infradead.org
optimize_kprobe() and unoptimize_kprobe() cancels if a given kprobe
is on the optimizing_list or unoptimizing_list already. However, since
the following commit:
f66c0447cc ("kprobes: Set unoptimized flag after unoptimizing code")
modified the update timing of the KPROBE_FLAG_OPTIMIZED, it doesn't
work as expected anymore.
The optimized_kprobe could be in the following states:
- [optimizing]: Before inserting jump instruction
op.kp->flags has KPROBE_FLAG_OPTIMIZED and
op->list is not empty.
- [optimized]: jump inserted
op.kp->flags has KPROBE_FLAG_OPTIMIZED and
op->list is empty.
- [unoptimizing]: Before removing jump instruction (including unused
optprobe)
op.kp->flags has KPROBE_FLAG_OPTIMIZED and
op->list is not empty.
- [unoptimized]: jump removed
op.kp->flags doesn't have KPROBE_FLAG_OPTIMIZED and
op->list is empty.
Current code mis-expects [unoptimizing] state doesn't have
KPROBE_FLAG_OPTIMIZED, and that can cause incorrect results.
To fix this, introduce optprobe_queued_unopt() to distinguish [optimizing]
and [unoptimizing] states and fixes the logic in optimize_kprobe() and
unoptimize_kprobe().
[ mingo: Cleaned up the changelog and the code a bit. ]
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Fixes: f66c0447cc ("kprobes: Set unoptimized flag after unoptimizing code")
Link: https://lkml.kernel.org/r/157840814418.7181.13478003006386303481.stgit@devnote2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It is the same as machine_kexec_prepare(), but is called after segments are
loaded. This way, can do processing work with already loaded relocation
segments. One such example is arm64: it has to have segments loaded in
order to create a page table, but it cannot do it during kexec time,
because at that time allocations won't be possible anymore.
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
Here is a regular kexec command sequence and output:
=====
$ kexec --reuse-cmdline -i --load Image
$ kexec -e
[ 161.342002] kexec_core: Starting new kernel
Welcome to Buildroot
buildroot login:
=====
Even when "quiet" kernel parameter is specified, "kexec_core: Starting
new kernel" is printed.
This message has KERN_EMERG level, but there is no emergency, it is a
normal kexec operation, so quiet it down to appropriate KERN_NOTICE.
Machines that have slow console baud rate benefit from less output.
Signed-off-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Simon Horman <horms@verge.net.au>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Will Deacon <will@kernel.org>
In module_add_modinfo_attrs() if sysfs_create_file() fails
on the first iteration of the loop (so i = 0), we forget to
free the modinfo_attrs.
Fixes: bc6f2a757d ("kernel/module: Fix mem leak in module_add_modinfo_attrs")
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
copy_thread implementations handle CLONE_SETTLS by reading the TLS
value from the registers containing the syscall arguments for
clone. This doesn't work with clone3 since the TLS value is passed
in clone_args instead.
Signed-off-by: Amanieu d'Antras <amanieu@gmail.com>
Cc: <stable@vger.kernel.org> # 5.3.x
Link: https://lore.kernel.org/r/20200102172413.654385-8-amanieu@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Hibernation fails when the kernel cannot allocate enough memory
to copy all pages of RAM in use.
Ensure that the failure reason is clearly logged, and clearly
attributable to the hibernation module.
Signed-off-by: Luigi Semenzato <semenzato@google.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
do_div() does a 64-by-32 division. Use div64_u64() instead of
do_div() if the divisor is u64, to avoid truncation to 32-bit.
This change also cleans up code a tad.
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- kbuild found missing define of MCOUNT_INSN_SIZE for various build configs
- Initialize variable to zero as gcc thinks it is used undefined
(it really isn't but the code is subtle enough that this doesn't hurt)
- Convert from do_div() to div64_ull() to prevent potential divide by zero
- Unregister a trace point on error path in sched_wakeup tracer
- Use signed offset for archs that can have stext not be first
- A simple indentation fix (whitespace error)
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXhOj6xQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qukzAQCMNfkAbMFA+C1uORMhr/jWhi4eshWN
4jZ2u5X8zGuuXQD+PaQU4n8d0K4uCPF+lFD16DfFxXvCOXHfN3/zXmxGvw8=
=djaW
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Various tracing fixes:
- kbuild found missing define of MCOUNT_INSN_SIZE for various build
configs
- Initialize variable to zero as gcc thinks it is used undefined (it
really isn't but the code is subtle enough that this doesn't hurt)
- Convert from do_div() to div64_ull() to prevent potential divide by
zero
- Unregister a trace point on error path in sched_wakeup tracer
- Use signed offset for archs that can have stext not be first
- A simple indentation fix (whitespace error)"
* tag 'trace-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix indentation issue
kernel/trace: Fix do not unregister tracepoints when register sched_migrate_task fail
tracing: Change offset type to s32 in preempt/irq tracepoints
ftrace: Avoid potential division by zero in function profiler
tracing: Have stack tracer compile when MCOUNT_INSN_SIZE is not defined
tracing: Define MCOUNT_INSN_SIZE when not defined without direct calls
tracing: Initialize val to zero in parse_entry of inject code
Before commit 4bfc0bb2c6 ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself")
cgroup bpf structures were released with
corresponding cgroup structures. It guaranteed the hierarchical order
of destruction: children were always first. It preserved attached
programs from being released before their propagated copies.
But with cgroup auto-detachment there are no such guarantees anymore:
cgroup bpf is released as soon as the cgroup is offline and there are
no live associated sockets. It means that an attached program can be
detached and released, while its propagated copy is still living
in the cgroup subtree. This will obviously lead to an use-after-free
bug.
To reproduce the issue the following script can be used:
#!/bin/bash
CGROOT=/sys/fs/cgroup
mkdir -p ${CGROOT}/A ${CGROOT}/B ${CGROOT}/A/C
sleep 1
./test_cgrp2_attach ${CGROOT}/A egress &
A_PID=$!
./test_cgrp2_attach ${CGROOT}/B egress &
B_PID=$!
echo $$ > ${CGROOT}/A/C/cgroup.procs
iperf -s &
S_PID=$!
iperf -c localhost -t 100 &
C_PID=$!
sleep 1
echo $$ > ${CGROOT}/B/cgroup.procs
echo ${S_PID} > ${CGROOT}/B/cgroup.procs
echo ${C_PID} > ${CGROOT}/B/cgroup.procs
sleep 1
rmdir ${CGROOT}/A/C
rmdir ${CGROOT}/A
sleep 1
kill -9 ${S_PID} ${C_PID} ${A_PID} ${B_PID}
On the unpatched kernel the following stacktrace can be obtained:
[ 33.619799] BUG: unable to handle page fault for address: ffffbdb4801ab002
[ 33.620677] #PF: supervisor read access in kernel mode
[ 33.621293] #PF: error_code(0x0000) - not-present page
[ 33.622754] Oops: 0000 [#1] SMP NOPTI
[ 33.623202] CPU: 0 PID: 601 Comm: iperf Not tainted 5.5.0-rc2+ #23
[ 33.625545] RIP: 0010:__cgroup_bpf_run_filter_skb+0x29f/0x3d0
[ 33.635809] Call Trace:
[ 33.636118] ? __cgroup_bpf_run_filter_skb+0x2bf/0x3d0
[ 33.636728] ? __switch_to_asm+0x40/0x70
[ 33.637196] ip_finish_output+0x68/0xa0
[ 33.637654] ip_output+0x76/0xf0
[ 33.638046] ? __ip_finish_output+0x1c0/0x1c0
[ 33.638576] __ip_queue_xmit+0x157/0x410
[ 33.639049] __tcp_transmit_skb+0x535/0xaf0
[ 33.639557] tcp_write_xmit+0x378/0x1190
[ 33.640049] ? _copy_from_iter_full+0x8d/0x260
[ 33.640592] tcp_sendmsg_locked+0x2a2/0xdc0
[ 33.641098] ? sock_has_perm+0x10/0xa0
[ 33.641574] tcp_sendmsg+0x28/0x40
[ 33.641985] sock_sendmsg+0x57/0x60
[ 33.642411] sock_write_iter+0x97/0x100
[ 33.642876] new_sync_write+0x1b6/0x1d0
[ 33.643339] vfs_write+0xb6/0x1a0
[ 33.643752] ksys_write+0xa7/0xe0
[ 33.644156] do_syscall_64+0x5b/0x1b0
[ 33.644605] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix this by grabbing a reference to the bpf structure of each ancestor
on the initialization of the cgroup bpf structure, and dropping the
reference at the end of releasing the cgroup bpf structure.
This will restore the hierarchical order of cgroup bpf releasing,
without adding any operations on hot paths.
Thanks to Josef Bacik for the debugging and the initial analysis of
the problem.
Fixes: 4bfc0bb2c6 ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself")
Reported-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Roman Gushchin <guro@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The cred_jar kmem_cache is already memcg accounted in the current kernel
but cred->security is not. Account cred->security to kmemcg.
Recently we saw high root slab usage on our production and on further
inspection, we found a buggy application leaking processes. Though that
buggy application was contained within its memcg but we observe much
more system memory overhead, couple of GiBs, during that period. This
overhead can adversely impact the isolation on the system.
One source of high overhead we found was cred->security objects, which
have a lifetime of at least the life of the process which allocated
them.
Link: http://lkml.kernel.org/r/20191205223721.40034-1-shakeelb@google.com
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Chris Down <chris@chrisdown.name>
Reviewed-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXg9C5wAKCRCRxhvAZXjc
oiZXAPsGFXyDCWlKnShBpKufdFh6XugADlyZK0Si2ISWQoJJsgD/Ri1g3zg6V7YC
HBG0sz8+vSk/Ys55yDQz+K1d1MTkdQ4=
=8uQe
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2020-01-03' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread fixes from Christian Brauner:
"Here are two fixes:
- Panic earlier when global init exits to generate useable coredumps.
Currently, when global init and all threads in its thread-group
have exited we panic via:
do_exit()
-> exit_notify()
-> forget_original_parent()
-> find_child_reaper()
This makes it hard to extract a useable coredump for global init
from a kernel crashdump because by the time we panic exit_mm() will
have already released global init's mm. We now panic slightly
earlier. This has been a problem in certain environments such as
Android.
- Fix a race in assigning and reading taskstats for thread-groups
with more than one thread.
This patch has been waiting for quite a while since people
disagreed on what the correct fix was at first"
* tag 'for-linus-2020-01-03' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
exit: panic before exit_mm() on global init exit
taskstats: fix data-race
In the function, if register_trace_sched_migrate_task() returns error,
sched_switch/sched_wakeup_new/sched_wakeup won't unregister. That is
why fail_deprobe_sched_switch was added.
Link: http://lkml.kernel.org/r/20191231133530.2794-1-pilgrimtao@gmail.com
Cc: stable@vger.kernel.org
Fixes: 478142c39c ("tracing: do not grab lock in wakeup latency function tracing")
Signed-off-by: Kaitao Cheng <pilgrimtao@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The ftrace_profile->counter is unsigned long and
do_div truncates it to 32 bits, which means it can test
non-zero and be truncated to zero for division.
Fix this issue by using div64_ul() instead.
Link: http://lkml.kernel.org/r/20200103030248.14516-1-wenyang@linux.alibaba.com
Cc: stable@vger.kernel.org
Fixes: e330b3bcd8 ("tracing: Show sample std dev in function profiling")
Fixes: 34886c8bc5 ("tracing: add average time in function to function profiler")
Signed-off-by: Wen Yang <wenyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
On some archs with some configurations, MCOUNT_INSN_SIZE is not defined, and
this makes the stack tracer fail to compile. Just define it to zero in this
case.
Link: https://lore.kernel.org/r/202001020219.zvE3vsty%lkp@intel.com
Cc: stable@vger.kernel.org
Fixes: 4df297129f ("tracing: Remove most or all of stack tracer stack size from stack_max_size")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In order to handle direct calls along side of function graph tracer, a check
is made to see if the address being traced by the function graph tracer is a
direct call or not. To get the address used by direct callers, the return
address is subtracted by MCOUNT_INSN_SIZE.
For some archs with certain configurations, MCOUNT_INSN_SIZE is undefined
here. But these should not be using direct calls anyway. Just define
MCOUNT_INSN_SIZE to zero in this case.
Link: https://lore.kernel.org/r/202001020219.zvE3vsty%lkp@intel.com
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: ff205766db ("ftrace: Fix function_graph tracer interaction with BPF trampoline")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Fix samples and selftests to zero passed-in buffer (Sargun Dhillon)
- Enforce zeroed buffer checking (Sargun Dhillon)
- Verify buffer sanity check in selftest (Sargun Dhillon)
-----BEGIN PGP SIGNATURE-----
Comment: Kees Cook <kees@outflux.net>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=WgBI
-----END PGP SIGNATURE-----
Merge tag 'seccomp-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp fixes from Kees Cook:
"Fixes for seccomp_notify_ioctl uapi sanity from Sargun Dhillon.
The bulk of this is fixing the surrounding samples and selftests so
that seccomp can correctly validate the seccomp_notify_ioctl buffer as
being initially zeroed.
Summary:
- Fix samples and selftests to zero passed-in buffer
- Enforce zeroed buffer checking
- Verify buffer sanity check in selftest"
* tag 'seccomp-v5.5-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests/seccomp: Catch garbage on SECCOMP_IOCTL_NOTIF_RECV
seccomp: Check that seccomp_notif is zeroed out by the user
selftests/seccomp: Zero out seccomp_notif
samples/seccomp: Zero out members based on seccomp_notif_sizes
gcc produces a variable may be uninitialized warning for "val" in
parse_entry(). This is really a false positive, but the code is subtle
enough to just initialize val to zero and it's not a fast path to worry
about it.
Marked for stable to remove the warning in the stable trees as well.
Cc: stable@vger.kernel.org
Fixes: 6c3edaf9fd ("tracing: Introduce trace event injection")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This patch is a small change in enforcement of the uapi for
SECCOMP_IOCTL_NOTIF_RECV ioctl. Specifically, the datastructure which
is passed (seccomp_notif) must be zeroed out. Previously any of its
members could be set to nonsense values, and we would ignore it.
This ensures all fields are set to their zero value.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Aleksa Sarai <cyphar@cyphar.com>
Acked-by: Tycho Andersen <tycho@tycho.ws>
Link: https://lore.kernel.org/r/20191229062451.9467-2-sargun@sargun.me
Fixes: 6a21cc50f0 ("seccomp: add a return code to trap to userspace")
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Commit f92b070f2d ("printk: Do not miss new messages when replaying
the log") introduced a new variable @exclusive_console_stop_seq to
store when an exclusive console should stop printing. It should be
set to the @console_seq value at registration. However, @console_seq
is previously set to @syslog_seq so that the exclusive console knows
where to begin. This results in the exclusive console immediately
reactivating all the other consoles and thus repeating the messages
for those consoles.
Set @console_seq after @exclusive_console_stop_seq has stored the
current @console_seq value.
Fixes: f92b070f2d ("printk: Do not miss new messages when replaying the log")
Link: http://lkml.kernel.org/r/20191219115322.31160-1-john.ogness@linutronix.de
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
In a case when a ptp chardev (like /dev/ptp0) is open but an underlying
device is removed, closing this file leads to a race. This reproduces
easily in a kvm virtual machine:
ts# cat openptp0.c
int main() { ... fp = fopen("/dev/ptp0", "r"); ... sleep(10); }
ts# uname -r
5.5.0-rc3-46cf053e
ts# cat /proc/cmdline
... slub_debug=FZP
ts# modprobe ptp_kvm
ts# ./openptp0 &
[1] 670
opened /dev/ptp0, sleeping 10s...
ts# rmmod ptp_kvm
ts# ls /dev/ptp*
ls: cannot access '/dev/ptp*': No such file or directory
ts# ...woken up
[ 48.010809] general protection fault: 0000 [#1] SMP
[ 48.012502] CPU: 6 PID: 658 Comm: openptp0 Not tainted 5.5.0-rc3-46cf053e #25
[ 48.014624] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), ...
[ 48.016270] RIP: 0010:module_put.part.0+0x7/0x80
[ 48.017939] RSP: 0018:ffffb3850073be00 EFLAGS: 00010202
[ 48.018339] RAX: 000000006b6b6b6b RBX: 6b6b6b6b6b6b6b6b RCX: ffff89a476c00ad0
[ 48.018936] RDX: fffff65a08d3ea08 RSI: 0000000000000247 RDI: 6b6b6b6b6b6b6b6b
[ 48.019470] ... ^^^ a slub poison
[ 48.023854] Call Trace:
[ 48.024050] __fput+0x21f/0x240
[ 48.024288] task_work_run+0x79/0x90
[ 48.024555] do_exit+0x2af/0xab0
[ 48.024799] ? vfs_write+0x16a/0x190
[ 48.025082] do_group_exit+0x35/0x90
[ 48.025387] __x64_sys_exit_group+0xf/0x10
[ 48.025737] do_syscall_64+0x3d/0x130
[ 48.026056] entry_SYSCALL_64_after_hwframe+0x44/0xa9
[ 48.026479] RIP: 0033:0x7f53b12082f6
[ 48.026792] ...
[ 48.030945] Modules linked in: ptp i6300esb watchdog [last unloaded: ptp_kvm]
[ 48.045001] Fixing recursive fault but reboot is needed!
This happens in:
static void __fput(struct file *file)
{ ...
if (file->f_op->release)
file->f_op->release(inode, file); <<< cdev is kfree'd here
if (unlikely(S_ISCHR(inode->i_mode) && inode->i_cdev != NULL &&
!(mode & FMODE_PATH))) {
cdev_put(inode->i_cdev); <<< cdev fields are accessed here
Namely:
__fput()
posix_clock_release()
kref_put(&clk->kref, delete_clock) <<< the last reference
delete_clock()
delete_ptp_clock()
kfree(ptp) <<< cdev is embedded in ptp
cdev_put
module_put(p->owner) <<< *p is kfree'd, bang!
Here cdev is embedded in posix_clock which is embedded in ptp_clock.
The race happens because ptp_clock's lifetime is controlled by two
refcounts: kref and cdev.kobj in posix_clock. This is wrong.
Make ptp_clock's sysfs device a parent of cdev with cdev_device_add()
created especially for such cases. This way the parent device with its
ptp_clock is not released until all references to the cdev are released.
This adds a requirement that an initialized but not exposed struct
device should be provided to posix_clock_register() by a caller instead
of a simple dev_t.
This approach was adopted from the commit 72139dfa24 ("watchdog: Fix
the race between the release of watchdog_core_data and cdev"). See
details of the implementation in the commit 233ed09d7f ("chardev: add
helper function to register char devs with a struct device").
Link: https://lore.kernel.org/linux-fsdevel/20191125125342.6189-1-vdronov@redhat.com/T/#u
Analyzed-by: Stephen Johnston <sjohnsto@redhat.com>
Analyzed-by: Vern Lovejoy <vlovejoy@redhat.com>
Signed-off-by: Vladis Dronov <vdronov@redhat.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-12-27
The following pull-request contains BPF updates for your *net-next* tree.
We've added 127 non-merge commits during the last 17 day(s) which contain
a total of 110 files changed, 6901 insertions(+), 2721 deletions(-).
There are three merge conflicts. Conflicts and resolution looks as follows:
1) Merge conflict in net/bpf/test_run.c:
There was a tree-wide cleanup c593642c8b ("treewide: Use sizeof_field() macro")
which gets in the way with b590cb5f80 ("bpf: Switch to offsetofend in
BPF_PROG_TEST_RUN"):
<<<<<<< HEAD
if (!range_is_zero(__skb, offsetof(struct __sk_buff, priority) +
sizeof_field(struct __sk_buff, priority),
=======
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, priority),
>>>>>>> 7c8dce4b16
There are a few occasions that look similar to this. Always take the chunk with
offsetofend(). Note that there is one where the fields differ in here:
<<<<<<< HEAD
if (!range_is_zero(__skb, offsetof(struct __sk_buff, tstamp) +
sizeof_field(struct __sk_buff, tstamp),
=======
if (!range_is_zero(__skb, offsetofend(struct __sk_buff, gso_segs),
>>>>>>> 7c8dce4b16
Just take the one with offsetofend() /and/ gso_segs. Latter is correct due to
850a88cc40 ("bpf: Expose __sk_buff wire_len/gso_segs to BPF_PROG_TEST_RUN").
2) Merge conflict in arch/riscv/net/bpf_jit_comp.c:
(I'm keeping Bjorn in Cc here for a double-check in case I got it wrong.)
<<<<<<< HEAD
if (is_13b_check(off, insn))
return -1;
emit(rv_blt(tcc, RV_REG_ZERO, off >> 1), ctx);
=======
emit_branch(BPF_JSLT, RV_REG_T1, RV_REG_ZERO, off, ctx);
>>>>>>> 7c8dce4b16
Result should look like:
emit_branch(BPF_JSLT, tcc, RV_REG_ZERO, off, ctx);
3) Merge conflict in arch/riscv/include/asm/pgtable.h:
<<<<<<< HEAD
=======
#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1)
#define VMALLOC_END (PAGE_OFFSET - 1)
#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE)
#define BPF_JIT_REGION_SIZE (SZ_128M)
#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE)
#define BPF_JIT_REGION_END (VMALLOC_END)
/*
* Roughly size the vmemmap space to be large enough to fit enough
* struct pages to map half the virtual address space. Then
* position vmemmap directly below the VMALLOC region.
*/
#define VMEMMAP_SHIFT \
(CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)
#define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT)
#define VMEMMAP_END (VMALLOC_START - 1)
#define VMEMMAP_START (VMALLOC_START - VMEMMAP_SIZE)
#define vmemmap ((struct page *)VMEMMAP_START)
>>>>>>> 7c8dce4b16
Only take the BPF_* defines from there and move them higher up in the
same file. Remove the rest from the chunk. The VMALLOC_* etc defines
got moved via 01f52e16b8 ("riscv: define vmemmap before pfn_to_page
calls"). Result:
[...]
#define __S101 PAGE_READ_EXEC
#define __S110 PAGE_SHARED_EXEC
#define __S111 PAGE_SHARED_EXEC
#define VMALLOC_SIZE (KERN_VIRT_SIZE >> 1)
#define VMALLOC_END (PAGE_OFFSET - 1)
#define VMALLOC_START (PAGE_OFFSET - VMALLOC_SIZE)
#define BPF_JIT_REGION_SIZE (SZ_128M)
#define BPF_JIT_REGION_START (PAGE_OFFSET - BPF_JIT_REGION_SIZE)
#define BPF_JIT_REGION_END (VMALLOC_END)
/*
* Roughly size the vmemmap space to be large enough to fit enough
* struct pages to map half the virtual address space. Then
* position vmemmap directly below the VMALLOC region.
*/
#define VMEMMAP_SHIFT \
(CONFIG_VA_BITS - PAGE_SHIFT - 1 + STRUCT_PAGE_MAX_SHIFT)
#define VMEMMAP_SIZE BIT(VMEMMAP_SHIFT)
#define VMEMMAP_END (VMALLOC_START - 1)
#define VMEMMAP_START (VMALLOC_START - VMEMMAP_SIZE)
[...]
Let me know if there are any other issues.
Anyway, the main changes are:
1) Extend bpftool to produce a struct (aka "skeleton") tailored and specific
to a provided BPF object file. This provides an alternative, simplified API
compared to standard libbpf interaction. Also, add libbpf extern variable
resolution for .kconfig section to import Kconfig data, from Andrii Nakryiko.
2) Add BPF dispatcher for XDP which is a mechanism to avoid indirect calls by
generating a branch funnel as discussed back in bpfconf'19 at LSF/MM. Also,
add various BPF riscv JIT improvements, from Björn Töpel.
3) Extend bpftool to allow matching BPF programs and maps by name,
from Paul Chaignon.
4) Support for replacing cgroup BPF programs attached with BPF_F_ALLOW_MULTI
flag for allowing updates without service interruption, from Andrey Ignatov.
5) Cleanup and simplification of ring access functions for AF_XDP with a
bonus of 0-5% performance improvement, from Magnus Karlsson.
6) Enable BPF JITs for x86-64 and arm64 by default. Also, final version of
audit support for BPF, from Daniel Borkmann and latter with Jiri Olsa.
7) Move and extend test_select_reuseport into BPF program tests under
BPF selftests, from Jakub Sitnicki.
8) Various BPF sample improvements for xdpsock for customizing parameters
to set up and benchmark AF_XDP, from Jay Jayatheerthan.
9) Improve libbpf to provide a ulimit hint on permission denied errors.
Also change XDP sample programs to attach in driver mode by default,
from Toke Høiland-Jørgensen.
10) Extend BPF test infrastructure to allow changing skb mark from tc BPF
programs, from Nikita V. Shirokov.
11) Optimize prologue code sequence in BPF arm32 JIT, from Russell King.
12) Fix xdp_redirect_cpu BPF sample to manually attach to tracepoints after
libbpf conversion, from Jesper Dangaard Brouer.
13) Minor misc improvements from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
If the lockdep code is really running out of the stack_trace entries,
it is likely that buffer overrun can happen and the data immediately
after stack_trace[] will be corrupted.
If there is less than LOCK_TRACE_SIZE_IN_LONGS entries left before
the call to save_trace(), the max_entries computation will leave it
with a very large positive number because of its unsigned nature. The
subsequent call to stack_trace_save() will then corrupt the data after
stack_trace[]. Fix that by changing max_entries to a signed integer
and check for negative value before calling stack_trace_save().
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 12593b7467 ("locking/lockdep: Reduce space occupied by stack traces")
Link: https://lkml.kernel.org/r/20191220135128.14876-1-longman@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Capacity Awareness refers to the fact that on heterogeneous systems
(like Arm big.LITTLE), the capacity of the CPUs is not uniform, hence
when placing tasks we need to be aware of this difference of CPU
capacities.
In such scenarios we want to ensure that the selected CPU has enough
capacity to meet the requirement of the running task. Enough capacity
means here that capacity_orig_of(cpu) >= task.requirement.
The definition of task.requirement is dependent on the scheduling class.
For CFS, utilization is used to select a CPU that has >= capacity value
than the cfs_task.util.
capacity_orig_of(cpu) >= cfs_task.util
DL isn't capacity aware at the moment but can make use of the bandwidth
reservation to implement that in a similar manner CFS uses utilization.
The following patchset implements that:
https://lore.kernel.org/lkml/20190506044836.2914-1-luca.abeni@santannapisa.it/
capacity_orig_of(cpu)/SCHED_CAPACITY >= dl_deadline/dl_runtime
For RT we don't have a per task utilization signal and we lack any
information in general about what performance requirement the RT task
needs. But with the introduction of uclamp, RT tasks can now control
that by setting uclamp_min to guarantee a minimum performance point.
ATM the uclamp value are only used for frequency selection; but on
heterogeneous systems this is not enough and we need to ensure that the
capacity of the CPU is >= uclamp_min. Which is what implemented here.
capacity_orig_of(cpu) >= rt_task.uclamp_min
Note that by default uclamp.min is 1024, which means that RT tasks will
always be biased towards the big CPUs, which make for a better more
predictable behavior for the default case.
Must stress that the bias acts as a hint rather than a definite
placement strategy. For example, if all big cores are busy executing
other RT tasks we can't guarantee that a new RT task will be placed
there.
On non-heterogeneous systems the original behavior of RT should be
retained. Similarly if uclamp is not selected in the config.
[ mingo: Minor edits to comments. ]
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191009104611.15363-1-qais.yousef@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
task_fits_capacity() has just been made uclamp-aware, and
find_energy_efficient_cpu() needs to go through the same treatment.
Things are somewhat different here however - using the task max clamp isn't
sufficient. Consider the following setup:
The target runqueue, rq:
rq.cpu_capacity_orig = 512
rq.cfs.avg.util_avg = 200
rq.uclamp.max = 768 // the max p.uclamp.max of all enqueued p's is 768
The waking task, p (not yet enqueued on rq):
p.util_est = 600
p.uclamp.max = 100
Now, consider the following code which doesn't use the rq clamps:
util = uclamp_task_util(p);
// Does the task fit in the spare CPU capacity?
cpu = cpu_of(rq);
fits_capacity(util, cpu_capacity(cpu) - cpu_util(cpu))
This would lead to:
util = 100;
fits_capacity(100, 512 - 200)
fits_capacity() would return true. However, enqueuing p on that CPU *will*
cause it to become overutilized since rq clamp values are max-aggregated,
so we'd remain with
rq.uclamp.max = 768
which comes from the other tasks already enqueued on rq. Thus, we could
select a high enough frequency to reach beyond 0.8 * 512 utilization
(== overutilized) after enqueuing p on rq. What find_energy_efficient_cpu()
needs here is uclamp_rq_util_with() which lets us peek at the future
utilization landscape, including rq-wide uclamp values.
Make find_energy_efficient_cpu() use uclamp_rq_util_with() for its
fits_capacity() check. This is in line with what compute_energy() ends up
using for estimating utilization.
Tested-By: Dietmar Eggemann <dietmar.eggemann@arm.com>
Suggested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191211113851.24241-6-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
task_fits_capacity() drives CPU selection at wakeup time, and is also used
to detect misfit tasks. Right now it does so by comparing task_util_est()
with a CPU's capacity, but doesn't take into account uclamp restrictions.
There's a few interesting uses that can come out of doing this. For
instance, a low uclamp.max value could prevent certain tasks from being
flagged as misfit tasks, so they could merrily remain on low-capacity CPUs.
Similarly, a high uclamp.min value would steer tasks towards high capacity
CPUs at wakeup (and, should that fail, later steered via misfit balancing),
so such "boosted" tasks would favor CPUs of higher capacity.
Introduce uclamp_task_util() and make task_fits_capacity() use it.
Tested-By: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191211113851.24241-5-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current helper returns (CPU) rq utilization with uclamp restrictions
taken into account. A uclamp task utilization helper would be quite
helpful, but this requires some renaming.
Prepare the code for the introduction of a uclamp_task_util() by renaming
the existing uclamp_util_with() to uclamp_rq_util_with().
Tested-By: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191211113851.24241-4-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Vincent pointed out recently that the canonical type for utilization
values is 'unsigned long'. Internally uclamp uses 'unsigned int' values for
cache optimization, but this doesn't have to be exported to its users.
Make the uclamp helpers that deal with utilization use and return unsigned
long values.
Tested-By: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191211113851.24241-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The sole user of uclamp_util(), schedutil_cpu_util(), was made to use
uclamp_util_with() instead in commit:
af24bde8df ("sched/uclamp: Add uclamp support to energy_compute()")
From then on, uclamp_util() has remained unused. Being a simple wrapper
around uclamp_util_with(), we can get rid of it and win back a few lines.
Tested-By: Dietmar Eggemann <dietmar.eggemann@arm.com>
Suggested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191211113851.24241-2-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There are instances where we keep searching for an idle CPU despite
already having a sched-idle CPU (in find_idlest_group_cpu(),
select_idle_smt() and select_idle_cpu() and then there are places where
we don't necessarily do that and return a sched-idle CPU as soon as we
find one (in select_idle_sibling()). This looks a bit inconsistent and
it may be worth having the same policy everywhere.
On the other hand, choosing a sched-idle CPU over a idle one shall be
beneficial from performance and power point of view as well, as we don't
need to get the CPU online from a deep idle state which wastes quite a
lot of time and energy and delays the scheduling of the newly woken up
task.
This patch tries to simplify code around sched-idle CPU selection and
make it consistent throughout.
Testing is done with the help of rt-app on hikey board (ARM64 octa-core,
2 clusters, 0-3 and 4-7). The cpufreq governor was set to performance to
avoid any side affects from CPU frequency. Following are the tests
performed:
Test 1: 1-cfs-task:
A single SCHED_NORMAL task is pinned to CPU5 which runs for 2333 us
out of 7777 us (so gives time for the cluster to go in deep idle
state).
Test 2: 1-cfs-1-idle-task:
A single SCHED_NORMAL task is pinned on CPU5 and single SCHED_IDLE
task is pinned on CPU6 (to make sure cluster 1 doesn't go in deep idle
state).
Test 3: 1-cfs-8-idle-task:
A single SCHED_NORMAL task is pinned on CPU5 and eight SCHED_IDLE
tasks are created which run forever (not pinned anywhere, so they run
on all CPUs). Checked with kernelshark that as soon as NORMAL task
sleeps, the SCHED_IDLE task starts running on CPU5.
And here are the results on mean latency (in us), using the "st" tool.
$ st 1-cfs-task/rt-app-cfs_thread-0.log
N min max sum mean stddev
642 90 592 197180 307.134 109.906
$ st 1-cfs-1-idle-task/rt-app-cfs_thread-0.log
N min max sum mean stddev
642 67 311 113850 177.336 41.4251
$ st 1-cfs-8-idle-task/rt-app-cfs_thread-0.log
N min max sum mean stddev
643 29 173 41364 64.3297 13.2344
The mean latency when we need to:
- wakeup from deep idle state is 307 us.
- wakeup from shallow idle state is 177 us.
- preempt a SCHED_IDLE task is 64 us.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/b90cbcce608cef4e02a7bbfe178335f76d201bab.1573728344.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This commit left behind an unused variable:
5443a0be61 ("sched: Use fair:prio_changed() instead of ad-hoc implementation") left behind an unused variable.
kernel/sched/core.c: In function 'set_user_nice':
kernel/sched/core.c:4507:16: warning: variable 'delta' set but not used
int old_prio, delta;
^~~~~
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 5443a0be61 ("sched: Use fair:prio_changed() instead of ad-hoc implementation")
Link: https://lkml.kernel.org/r/20191219140314.1252-1-cai@lca.pw
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It is preferrable to reject unknown flags within rseq unregistration
rather than to ignore them. It is an oversight caused by the fact that
the check for unknown flags is after the rseq unregister flag check.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191211161713.4490-2-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Anatoly has been fuzzing with kBdysch harness and reported a hang in one
of the outcomes. Upon closer analysis, it turns out that precise scalar
value tracking is missing a few precision markings for unknown scalars:
0: R1=ctx(id=0,off=0,imm=0) R10=fp0
0: (b7) r0 = 0
1: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
1: (35) if r0 >= 0xf72e goto pc+0
--> only follow fallthrough
2: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
2: (35) if r0 >= 0x80fe0000 goto pc+0
--> only follow fallthrough
3: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
3: (14) w0 -= -536870912
4: R0_w=invP536870912 R1=ctx(id=0,off=0,imm=0) R10=fp0
4: (0f) r1 += r0
5: R0_w=invP536870912 R1_w=inv(id=0) R10=fp0
5: (55) if r1 != 0x104c1500 goto pc+0
--> push other branch for later analysis
R0_w=invP536870912 R1_w=inv273421568 R10=fp0
6: R0_w=invP536870912 R1_w=inv273421568 R10=fp0
6: (b7) r0 = 0
7: R0=invP0 R1=inv273421568 R10=fp0
7: (76) if w1 s>= 0xffffff00 goto pc+3
--> only follow goto
11: R0=invP0 R1=inv273421568 R10=fp0
11: (95) exit
6: R0_w=invP536870912 R1_w=inv(id=0) R10=fp0
6: (b7) r0 = 0
propagating r0
7: safe
processed 11 insns [...]
In the analysis of the second path coming after the successful exit above,
the path is being pruned at line 7. Pruning analysis found that both r0 are
precise P0 and both R1 are non-precise scalars and given prior path with
R1 as non-precise scalar succeeded, this one is therefore safe as well.
However, problem is that given condition at insn 7 in the first run, we only
followed goto and didn't push the other branch for later analysis, we've
never walked the few insns in there and therefore dead-code sanitation
rewrites it as goto pc-1, causing the hang depending on the skb address
hitting these conditions. The issue is that R1 should have been marked as
precise as well such that pruning enforces range check and conluded that new
R1 is not in range of old R1. In insn 4, we mark R1 (skb) as unknown scalar
via __mark_reg_unbounded() but not mark_reg_unbounded() and therefore
regs->precise remains as false.
Back in b5dc0163d8 ("bpf: precise scalar_value tracking"), this was not
the case since marking out of __mark_reg_unbounded() had this covered as well.
Once in both are set as precise in 4 as they should have been, we conclude
that given R1 was in prior fall-through path 0x104c1500 and now is completely
unknown, the check at insn 7 concludes that we need to continue walking.
Analysis after the fix:
0: R1=ctx(id=0,off=0,imm=0) R10=fp0
0: (b7) r0 = 0
1: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
1: (35) if r0 >= 0xf72e goto pc+0
2: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
2: (35) if r0 >= 0x80fe0000 goto pc+0
3: R0_w=invP0 R1=ctx(id=0,off=0,imm=0) R10=fp0
3: (14) w0 -= -536870912
4: R0_w=invP536870912 R1=ctx(id=0,off=0,imm=0) R10=fp0
4: (0f) r1 += r0
5: R0_w=invP536870912 R1_w=invP(id=0) R10=fp0
5: (55) if r1 != 0x104c1500 goto pc+0
R0_w=invP536870912 R1_w=invP273421568 R10=fp0
6: R0_w=invP536870912 R1_w=invP273421568 R10=fp0
6: (b7) r0 = 0
7: R0=invP0 R1=invP273421568 R10=fp0
7: (76) if w1 s>= 0xffffff00 goto pc+3
11: R0=invP0 R1=invP273421568 R10=fp0
11: (95) exit
6: R0_w=invP536870912 R1_w=invP(id=0) R10=fp0
6: (b7) r0 = 0
7: R0_w=invP0 R1_w=invP(id=0) R10=fp0
7: (76) if w1 s>= 0xffffff00 goto pc+3
R0_w=invP0 R1_w=invP(id=0) R10=fp0
8: R0_w=invP0 R1_w=invP(id=0) R10=fp0
8: (a5) if r0 < 0x2007002a goto pc+0
9: R0_w=invP0 R1_w=invP(id=0) R10=fp0
9: (57) r0 &= -16316416
10: R0_w=invP0 R1_w=invP(id=0) R10=fp0
10: (a6) if w0 < 0x1201 goto pc+0
11: R0_w=invP0 R1_w=invP(id=0) R10=fp0
11: (95) exit
11: R0=invP0 R1=invP(id=0) R10=fp0
11: (95) exit
processed 16 insns [...]
Fixes: 6754172c20 ("bpf: fix precision tracking in presence of bpf2bpf calls")
Reported-by: Anatoly Trosinenko <anatoly.trosinenko@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191222223740.25297-1-daniel@iogearbox.net
Pull networking fixes from David Miller:
1) Several nf_flow_table_offload fixes from Pablo Neira Ayuso,
including adding a missing ipv6 match description.
2) Several heap overflow fixes in mwifiex from qize wang and Ganapathi
Bhat.
3) Fix uninit value in bond_neigh_init(), from Eric Dumazet.
4) Fix non-ACPI probing of nxp-nci, from Stephan Gerhold.
5) Fix use after free in tipc_disc_rcv(), from Tuong Lien.
6) Enforce limit of 33 tail calls in mips and riscv JIT, from Paul
Chaignon.
7) Multicast MAC limit test is off by one in qede, from Manish Chopra.
8) Fix established socket lookup race when socket goes from
TCP_ESTABLISHED to TCP_LISTEN, because there lacks an intervening
RCU grace period. From Eric Dumazet.
9) Don't send empty SKBs from tcp_write_xmit(), also from Eric Dumazet.
10) Fix active backup transition after link failure in bonding, from
Mahesh Bandewar.
11) Avoid zero sized hash table in gtp driver, from Taehee Yoo.
12) Fix wrong interface passed to ->mac_link_up(), from Russell King.
13) Fix DSA egress flooding settings in b53, from Florian Fainelli.
14) Memory leak in gmac_setup_txqs(), from Navid Emamdoost.
15) Fix double free in dpaa2-ptp code, from Ioana Ciornei.
16) Reject invalid MTU values in stmmac, from Jose Abreu.
17) Fix refcount leak in error path of u32 classifier, from Davide
Caratti.
18) Fix regression causing iwlwifi firmware crashes on boot, from Anders
Kaseorg.
19) Fix inverted return value logic in llc2 code, from Chan Shu Tak.
20) Disable hardware GRO when XDP is attached to qede, frm Manish
Chopra.
21) Since we encode state in the low pointer bits, dst metrics must be
at least 4 byte aligned, which is not necessarily true on m68k. Add
annotations to fix this, from Geert Uytterhoeven.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (160 commits)
sfc: Include XDP packet headroom in buffer step size.
sfc: fix channel allocation with brute force
net: dst: Force 4-byte alignment of dst_metrics
selftests: pmtu: fix init mtu value in description
hv_netvsc: Fix unwanted rx_table reset
net: phy: ensure that phy IDs are correctly typed
mod_devicetable: fix PHY module format
qede: Disable hardware gro when xdp prog is installed
net: ena: fix issues in setting interrupt moderation params in ethtool
net: ena: fix default tx interrupt moderation interval
net/smc: unregister ib devices in reboot_event
net: stmmac: platform: Fix MDIO init for platforms without PHY
llc2: Fix return statement of llc_stat_ev_rx_null_dsap_xid_c (and _test_c)
net: hisilicon: Fix a BUG trigered by wrong bytes_compl
net: dsa: ksz: use common define for tag len
s390/qeth: don't return -ENOTSUPP to userspace
s390/qeth: fix promiscuous mode after reset
s390/qeth: handle error due to unsupported transport mode
cxgb4: fix refcount init for TC-MQPRIO offload
tc-testing: initial tdc selftests for cls_u32
...
- Fix memory leak on error path of process_system_preds()
- Lock inversion fix with updating tgid recording option
- Fix histogram compare function on big endian machines
- Fix histogram trigger function on big endian machines
- Make trace_printk() irq sync on init for kprobe selftest correctness
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXf6MRxQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlw6AQCny2YeASymmOjDqh9/G53UdhO539Y2
oL/2nQ8B9T9KWgD6AmmohhbX+TS9l5Nwy2/bKmRgADZ7u+2XLM2f2mYR2Ag=
=D7hI
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Fix memory leak on error path of process_system_preds()
- Lock inversion fix with updating tgid recording option
- Fix histogram compare function on big endian machines
- Fix histogram trigger function on big endian machines
- Make trace_printk() irq sync on init for kprobe selftest correctness
* tag 'trace-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix endianness bug in histogram trigger
samples/trace_printk: Wait for IRQ work to finish
tracing: Fix lock inversion in trace_event_enable_tgid_record()
tracing: Have the histogram compare functions convert to u64 first
tracing: Avoid memory leak in process_system_preds()
At least on PA-RISC and s390 synthetic histogram triggers are failing
selftests because trace_event_raw_event_synth() always writes a 64 bit
values, but the reader expects a field->size sized value. On little endian
machines this doesn't hurt, but on big endian this makes the reader always
read zero values.
Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-4-svens@linux.ibm.com
Cc: stable@vger.kernel.org
Fixes: 4b147936fa ("tracing: Add support for 'synthetic' events")
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Task T2 Task T3
trace_options_core_write() subsystem_open()
mutex_lock(trace_types_lock) mutex_lock(event_mutex)
set_tracer_flag()
trace_event_enable_tgid_record() mutex_lock(trace_types_lock)
mutex_lock(event_mutex)
This gives a circular dependency deadlock between trace_types_lock and
event_mutex. To fix this invert the usage of trace_types_lock and
event_mutex in trace_options_core_write(). This keeps the sequence of
lock usage consistent.
Link: http://lkml.kernel.org/r/0101016eef175e38-8ca71caf-a4eb-480d-a1e6-6f0bbc015495-000000@us-west-2.amazonses.com
Cc: stable@vger.kernel.org
Fixes: d914ba37d7 ("tracing: Add support for recording tgid of tasks")
Signed-off-by: Prateek Sood <prsood@codeaurora.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull scheduler fixes from Ingo Molnar:
"Misc fixes: a (rare) PSI crash fix, a CPU affinity related balancing
fix, and a toning down of active migration attempts"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/cfs: fix spurious active migration
sched/fair: Fix find_idlest_group() to handle CPU affinity
psi: Fix a division error in psi poll()
sched/psi: Fix sampling error and rare div0 crashes with cgroups and high uptime
Pull perf fixes from Ingo Molnar:
"Misc fixes: a BTS fix, a PT NMI handling fix, a PMU sysfs fix and an
SRCU annotation"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Add SRCU annotation for pmus list walk
perf/x86/intel: Fix PT PMI handling
perf/x86/intel/bts: Fix the use of page_private()
perf/x86: Fix potential out-of-bounds access
Currently, when global init and all threads in its thread-group have exited
we panic via:
do_exit()
-> exit_notify()
-> forget_original_parent()
-> find_child_reaper()
This makes it hard to extract a useable coredump for global init from a
kernel crashdump because by the time we panic exit_mm() will have already
released global init's mm.
This patch moves the panic futher up before exit_mm() is called. As was the
case previously, we only panic when global init and all its threads in the
thread-group have exited.
Signed-off-by: chenqiwu <chenqiwu@xiaomi.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
[christian.brauner@ubuntu.com: fix typo, rewrite commit message]
Link: https://lore.kernel.org/r/1576736993-10121-1-git-send-email-qiwuchen55@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Call the 64bit versions of rtc_tm time conversion to avoid the y2038 issue.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The common use-case in production is to have multiple cgroup-bpf
programs per attach type that cover multiple use-cases. Such programs
are attached with BPF_F_ALLOW_MULTI and can be maintained by different
people.
Order of programs usually matters, for example imagine two egress
programs: the first one drops packets and the second one counts packets.
If they're swapped the result of counting program will be different.
It brings operational challenges with updating cgroup-bpf program(s)
attached with BPF_F_ALLOW_MULTI since there is no way to replace a
program:
* One way to update is to detach all programs first and then attach the
new version(s) again in the right order. This introduces an
interruption in the work a program is doing and may not be acceptable
(e.g. if it's egress firewall);
* Another way is attach the new version of a program first and only then
detach the old version. This introduces the time interval when two
versions of same program are working, what may not be acceptable if a
program is not idempotent. It also imposes additional burden on
program developers to make sure that two versions of their program can
co-exist.
Solve the problem by introducing a "replace" mode in BPF_PROG_ATTACH
command for cgroup-bpf programs being attached with BPF_F_ALLOW_MULTI
flag. This mode is enabled by newly introduced BPF_F_REPLACE attach flag
and bpf_attr.replace_bpf_fd attribute to pass fd of the old program to
replace
That way user can replace any program among those attached with
BPF_F_ALLOW_MULTI flag without the problems described above.
Details of the new API:
* If BPF_F_REPLACE is set but replace_bpf_fd doesn't have valid
descriptor of BPF program, BPF_PROG_ATTACH will return corresponding
error (EINVAL or EBADF).
* If replace_bpf_fd has valid descriptor of BPF program but such a
program is not attached to specified cgroup, BPF_PROG_ATTACH will
return ENOENT.
BPF_F_REPLACE is introduced to make the user intent clear, since
replace_bpf_fd alone can't be used for this (its default value, 0, is a
valid fd). BPF_F_REPLACE also makes it possible to extend the API in the
future (e.g. add BPF_F_BEFORE and BPF_F_AFTER if needed).
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Narkyiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/30cd850044a0057bdfcaaf154b7d2f39850ba813.1576741281.git.rdna@fb.com
__cgroup_bpf_attach has a lot of identical code to handle two scenarios:
BPF_F_ALLOW_MULTI is set and unset.
Simplify it by splitting the two main steps:
* First, the decision is made whether a new bpf_prog_list entry should
be allocated or existing entry should be reused for the new program.
This decision is saved in replace_pl pointer;
* Next, replace_pl pointer is used to handle both possible states of
BPF_F_ALLOW_MULTI flag (set / unset) instead of doing similar work for
them separately.
This splitting, in turn, allows to make further simplifications:
* The check for attaching same program twice in BPF_F_ALLOW_MULTI mode
can be done before allocating cgroup storage, so that if user tries to
attach same program twice no alloc/free happens as it was before;
* pl_was_allocated becomes redundant so it's removed.
Signed-off-by: Andrey Ignatov <rdna@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/c6193db6fe630797110b0d3ff06c125d093b834c.1576741281.git.rdna@fb.com
The cpumap flush list is used to track entries that need to flushed
from via the xdp_do_flush_map() function. This list used to be
per-map, but there is really no reason for that. Instead make the
flush list global for all devmaps, which simplifies __cpu_map_flush()
and cpu_map_alloc().
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20191219061006.21980-7-bjorn.topel@gmail.com
The devmap flush list is used to track entries that need to flushed
from via the xdp_do_flush_map() function. This list used to be
per-map, but there is really no reason for that. Instead make the
flush list global for all devmaps, which simplifies __dev_map_flush()
and dev_map_init_map().
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20191219061006.21980-6-bjorn.topel@gmail.com
The xskmap flush list is used to track entries that need to flushed
from via the xdp_do_flush_map() function. This list used to be
per-map, but there is really no reason for that. Instead make the
flush list global for all xskmaps, which simplifies __xsk_map_flush()
and xsk_map_alloc().
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20191219061006.21980-5-bjorn.topel@gmail.com
After the RCU flavor consolidation [1], call_rcu() and
synchronize_rcu() waits for preempt-disable regions (NAPI) in addition
to the read-side critical sections. As a result of this, the cleanup
code in cpumap can be simplified
* There is no longer a need to flush in __cpu_map_entry_free, since we
know that this has been done when the call_rcu() callback is
triggered.
* When freeing the map, there is no need to explicitly wait for a
flush. It's guaranteed to be done after the synchronize_rcu() call
in cpu_map_free().
[1] https://lwn.net/Articles/777036/
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20191219061006.21980-3-bjorn.topel@gmail.com
After the RCU flavor consolidation [1], call_rcu() and
synchronize_rcu() waits for preempt-disable regions (NAPI) in addition
to the read-side critical sections. As a result of this, the cleanup
code in devmap can be simplified
* There is no longer a need to flush in __dev_map_entry_free, since we
know that this has been done when the call_rcu() callback is
triggered.
* When freeing the map, there is no need to explicitly wait for a
flush. It's guaranteed to be done after the synchronize_rcu() call
in dev_map_free(). The rcu_barrier() is still needed, so that the
map is not freed prior the elements.
[1] https://lwn.net/Articles/777036/
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Toke Høiland-Jørgensen <toke@redhat.com>
Link: https://lore.kernel.org/bpf/20191219061006.21980-2-bjorn.topel@gmail.com
The compare functions of the histogram code would be specific for the size
of the value being compared (byte, short, int, long long). It would
reference the value from the array via the type of the compare, but the
value was stored in a 64 bit number. This is fine for little endian
machines, but for big endian machines, it would end up comparing zeros or
all ones (depending on the sign) for anything but 64 bit numbers.
To fix this, first derference the value as a u64 then convert it to the type
being compared.
Link: http://lkml.kernel.org/r/20191211103557.7bed6928@gandalf.local.home
Cc: stable@vger.kernel.org
Fixes: 08d43a5fa0 ("tracing: Add lock-free tracing_map")
Acked-by: Tom Zanussi <zanussi@kernel.org>
Reported-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
While testing Cilium with /unreleased/ Linus' tree under BPF-based NodePort
implementation, I noticed a strange BPF SNAT engine behavior from time to
time. In some cases it would do the correct SNAT/DNAT service translation,
but at a random point in time it would just stop and perform an unexpected
translation after SYN, SYN/ACK and stack would send a RST back. While initially
assuming that there is some sort of a race condition in BPF code, adding
trace_printk()s for debugging purposes at some point seemed to have resolved
the issue auto-magically.
Digging deeper on this Heisenbug and reducing the trace_printk() calls to
an absolute minimum, it turns out that a single call would suffice to
trigger / not trigger the seen RST issue, even though the logic of the
program itself remains unchanged. Turns out the single call changed verifier
pruning behavior to get everything to work. Reconstructing a minimal test
case, the incorrect JIT dump looked as follows:
# bpftool p d j i 11346
0xffffffffc0cba96c:
[...]
21: movzbq 0x30(%rdi),%rax
26: cmp $0xd,%rax
2a: je 0x000000000000003a
2c: xor %edx,%edx
2e: movabs $0xffff89cc74e85800,%rsi
38: jmp 0x0000000000000049
3a: mov $0x2,%edx
3f: movabs $0xffff89cc74e85800,%rsi
49: mov -0x224(%rbp),%eax
4f: cmp $0x20,%eax
52: ja 0x0000000000000062
54: add $0x1,%eax
57: mov %eax,-0x224(%rbp)
5d: jmpq 0xffffffffffff6911
62: mov $0x1,%eax
[...]
Hence, unexpectedly, JIT emitted a direct jump even though retpoline based
one would have been needed since in line 2c and 3a we have different slot
keys in BPF reg r3. Verifier log of the test case reveals what happened:
0: (b7) r0 = 14
1: (73) *(u8 *)(r1 +48) = r0
2: (71) r0 = *(u8 *)(r1 +48)
3: (15) if r0 == 0xd goto pc+4
R0_w=inv(id=0,umax_value=255,var_off=(0x0; 0xff)) R1=ctx(id=0,off=0,imm=0) R10=fp0
4: (b7) r3 = 0
5: (18) r2 = 0xffff89cc74d54a00
7: (05) goto pc+3
11: (85) call bpf_tail_call#12
12: (b7) r0 = 1
13: (95) exit
from 3 to 8: R0_w=inv13 R1=ctx(id=0,off=0,imm=0) R10=fp0
8: (b7) r3 = 2
9: (18) r2 = 0xffff89cc74d54a00
11: safe
processed 13 insns (limit 1000000) [...]
Second branch is pruned by verifier since considered safe, but issue is that
record_func_key() couldn't have seen the index in line 3a and therefore
decided that emitting a direct jump at this location was okay.
Fix this by reusing our backtracking logic for precise scalar verification
in order to prevent pruning on the slot key. This means verifier will track
content of r3 all the way backwards and only prune if both scalars were
unknown in state equivalence check and therefore poisoned in the first place
in record_func_key(). The range is [x,x] in record_func_key() case since
the slot always would have to be constant immediate. Correct verification
after fix:
0: (b7) r0 = 14
1: (73) *(u8 *)(r1 +48) = r0
2: (71) r0 = *(u8 *)(r1 +48)
3: (15) if r0 == 0xd goto pc+4
R0_w=invP(id=0,umax_value=255,var_off=(0x0; 0xff)) R1=ctx(id=0,off=0,imm=0) R10=fp0
4: (b7) r3 = 0
5: (18) r2 = 0x0
7: (05) goto pc+3
11: (85) call bpf_tail_call#12
12: (b7) r0 = 1
13: (95) exit
from 3 to 8: R0_w=invP13 R1=ctx(id=0,off=0,imm=0) R10=fp0
8: (b7) r3 = 2
9: (18) r2 = 0x0
11: (85) call bpf_tail_call#12
12: (b7) r0 = 1
13: (95) exit
processed 15 insns (limit 1000000) [...]
And correct corresponding JIT dump:
# bpftool p d j i 11
0xffffffffc0dc34c4:
[...]
21: movzbq 0x30(%rdi),%rax
26: cmp $0xd,%rax
2a: je 0x000000000000003a
2c: xor %edx,%edx
2e: movabs $0xffff9928b4c02200,%rsi
38: jmp 0x0000000000000049
3a: mov $0x2,%edx
3f: movabs $0xffff9928b4c02200,%rsi
49: cmp $0x4,%rdx
4d: jae 0x0000000000000093
4f: and $0x3,%edx
52: mov %edx,%edx
54: cmp %edx,0x24(%rsi)
57: jbe 0x0000000000000093
59: mov -0x224(%rbp),%eax
5f: cmp $0x20,%eax
62: ja 0x0000000000000093
64: add $0x1,%eax
67: mov %eax,-0x224(%rbp)
6d: mov 0x110(%rsi,%rdx,8),%rax
75: test %rax,%rax
78: je 0x0000000000000093
7a: mov 0x30(%rax),%rax
7e: add $0x19,%rax
82: callq 0x000000000000008e
87: pause
89: lfence
8c: jmp 0x0000000000000087
8e: mov %rax,(%rsp)
92: retq
93: mov $0x1,%eax
[...]
Also explicitly adding explicit env->allow_ptr_leaks to fixup_bpf_calls() since
backtracking is enabled under former (direct jumps as well, but use different
test). In case of only tracking different map pointers as in c93552c443 ("bpf:
properly enforce index mask to prevent out-of-bounds speculation"), pruning
cannot make such short-cuts, neither if there are paths with scalar and non-scalar
types as r3. mark_chain_precision() is only needed after we know that
register_is_const(). If it was not the case, we already poison the key on first
path and non-const key in later paths are not matching the scalar range in regsafe()
either. Cilium NodePort testing passes fine as well now. Note, released kernels
not affected.
Fixes: d2e4c1e6c2 ("bpf: Constant map key tracking for prog array pokes")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/ac43ffdeb7386c5bd688761ed266f3722bb39823.1576789878.git.daniel@iogearbox.net
The two callers of bpf_prog_realloc - bpf_patch_insn_single and
bpf_migrate_filter dereference the struct fp_old, before passing
it to the function. Thus assertion to check fp_old is unnecessary
and can be removed.
Signed-off-by: Aditya Pakki <pakki001@umn.edu>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191219175735.19231-1-pakki001@umn.edu
Fix a problem related to CPU offline/online and cpufreq governors
that in some system configurations may lead to a system-wide
deadlock during CPU online.
-----BEGIN PGP SIGNATURE-----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=+MQE
-----END PGP SIGNATURE-----
Merge tag 'pm-5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"Fix a problem related to CPU offline/online and cpufreq governors that
in some system configurations may lead to a system-wide deadlock
during CPU online"
* tag 'pm-5.5-rc3' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
cpufreq: Avoid leaving stale IRQ work items during CPU offline
Take the renaming of timeval and timespec one level further,
also renaming itimerval to __kernel_old_itimerval, to avoid
namespace conflicts with the user-space structure that may
use 64-bit time_t members.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Now that the last user of timespec_to_jiffies() is gone, these
can just be removed, everything else is using ktime_t or timespec64
already.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
As there is only a 32-bit ac_btime field in taskstat and
we should handle dates after the overflow, add a new field
with the same information but 64-bit width that can hold
a full time64_t.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
In 'struct acct', 'struct acct_v3', and 'struct taskstats' we have
a 32-bit 'ac_btime' field containing an absolute time value, which
will overflow in year 2106.
There are two possible ways to deal with it:
a) let it overflow and have user space code deal with reconstructing
the data based on the current time, or
b) truncate the times based on the range of the u32 type.
Neither of them solves the actual problem. Pick the second
one to best document what the issue is, and have someone
fix it in a future version.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Pull locking fixes from Ingo Molnar:
"Tone down mutex debugging complaints, and annotate/fix spinlock
debugging data accesses for KCSAN"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
Revert "locking/mutex: Complain upon mutex API misuse in IRQ contexts"
locking/spinlock/debug: Fix various data races
Recently noticed that we're tracking programs related to local storage maps
through their prog pointer. This is a wrong assumption since the prog pointer
can still change throughout the verification process, for example, whenever
bpf_patch_insn_single() is called.
Therefore, the prog pointer that was assigned via bpf_cgroup_storage_assign()
is not guaranteed to be the same as we pass in bpf_cgroup_storage_release()
and the map would therefore remain in busy state forever. Fix this by using
the prog's aux pointer which is stable throughout verification and beyond.
Fixes: de9cbbaadb ("bpf: introduce cgroup storage maps")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/1471c69eca3022218666f909bc927a92388fd09e.1576580332.git.daniel@iogearbox.net
try_stop_cpus is not used after this:
commit c190c3b16c ("rcu: Switch synchronize_sched_expedited() to
stop_one_cpu()")
So remove it.
Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191214195107.26480-1-tiny.windzz@gmail.com
Because of the:
if (!load)
runnable = running = 0;
clause in ___update_load_sum(), all the actual users of @contrib in
accumulate_sum():
if (load)
sa->load_sum += load * contrib;
if (runnable)
sa->runnable_load_sum += runnable * contrib;
if (running)
sa->util_sum += contrib << SCHED_CAPACITY_SHIFT;
don't happen, and therefore we don't care what @contrib actually is and
calculating it is pointless.
If we count the times when @load equals zero and not as below:
if (load) {
load_is_not_zero_count++;
contrib = __accumulate_pelt_segments(periods,
1024 - sa->period_contrib,delta);
} else
load_is_zero_count++;
As we can see, load_is_zero_count is much bigger than
load_is_zero_count, and the gap is gradually widening:
load_is_zero_count: 6016044 times
load_is_not_zero_count: 244316 times
19:50:43 up 1 min, 1 user, load average: 0.09, 0.06, 0.02
load_is_zero_count: 7956168 times
load_is_not_zero_count: 261472 times
19:51:42 up 2 min, 1 user, load average: 0.03, 0.05, 0.01
load_is_zero_count: 10199896 times
load_is_not_zero_count: 278364 times
19:52:51 up 3 min, 1 user, load average: 0.06, 0.05, 0.01
load_is_zero_count: 14333700 times
load_is_not_zero_count: 318424 times
19:54:53 up 5 min, 1 user, load average: 0.01, 0.03, 0.00
Perhaps we can gain some performance advantage by saving these
unnecessary calculation.
Signed-off-by: Peng Wang <rocking@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Vincent Guittot < vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/1576208740-35609-1-git-send-email-rocking@linux.alibaba.com
select_idle_cpu() will scan the LLC domain for idle CPUs,
it's always expensive. so the next commit :
1ad3aaf3fc ("sched/core: Implement new approach to scale select_idle_cpu()")
introduces a way to limit how many CPUs we scan.
But it consume some CPUs out of 'nr' that are not allowed
for the task and thus waste our attempts. The function
always return nr_cpumask_bits, and we can't find a CPU
which our task is allowed to run.
Cpumask may be too big, similar to select_idle_core(), use
per_cpu_ptr 'select_idle_mask' to prevent stack overflow.
Fixes: 1ad3aaf3fc ("sched/core: Implement new approach to scale select_idle_cpu()")
Signed-off-by: Cheng Jian <cj.chengjian@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20191213024530.28052-1-cj.chengjian@huawei.com
Paul reported a very sporadic, rcutorture induced, workqueue failure.
When the planets align, the workqueue rescuer's self-migrate fails and
then triggers a WARN for running a work on the wrong CPU.
Tejun then figured that set_cpus_allowed_ptr()'s stop_one_cpu() call
could be ignored! When stopper->enabled is false, stop_machine will
insta complete the work, without actually doing the work. Worse, it
will not WARN about this (we really should fix this).
It turns out there is a small window where a freshly online'ed CPU is
marked 'online' but doesn't yet have the stopper task running:
BP AP
bringup_cpu()
__cpu_up(cpu, idle) --> start_secondary()
...
cpu_startup_entry()
bringup_wait_for_ap()
wait_for_ap_thread() <-- cpuhp_online_idle()
while (1)
do_idle()
... available to run kthreads ...
stop_machine_unpark()
stopper->enable = true;
Close this by moving the stop_machine_unpark() into
cpuhp_online_idle(), such that the stopper thread is ready before we
start the idle loop and schedule.
Reported-by: "Paul E. McKenney" <paulmck@kernel.org>
Debugged-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: "Paul E. McKenney" <paulmck@kernel.org>
init_wait_var_entry() forgets to initialize wq_entry->flags.
Currently not a problem, we don't have wait_var_event_exclusive().
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Felipe Balbi <balbi@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20191210191902.GB14449@redhat.com
set_user_nice() implements its own version of fair::prio_changed() and
therefore misses a specific optimization towards nohz_full CPUs that
avoid sending an resched IPI to a reniced task running alone. Use the
proper callback instead.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191203160106.18806-3-frederic@kernel.org
The runqueue of a fair task being remotely reniced is going to get a
resched IPI in order to reassess which task should be the current
running on the CPU. However that evaluation is useless if the fair task
is running alone, in which case we can spare that IPI, preventing
nohz_full CPUs from being disturbed.
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20191203160106.18806-2-frederic@kernel.org
The load balance can fail to find a suitable task during the periodic check
because the imbalance is smaller than half of the load of the waiting
tasks. This results in the increase of the number of failed load balance,
which can end up to start an active migration. This active migration is
useless because the current running task is not a better choice than the
waiting ones. In fact, the current task was probably not running but
waiting for the CPU during one of the previous attempts and it had already
not been selected.
When load balance fails too many times to migrate a task, we should relax
the contraint on the maximum load of the tasks that can be migrated
similarly to what is done with cache hotness.
Before the rework, load balance used to set the imbalance to the average
load_per_task in order to mitigate such situation. This increased the
likelihood of migrating a task but also of selecting a larger task than
needed while more appropriate ones were in the list.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1575036287-6052-1-git-send-email-vincent.guittot@linaro.org
Because of CPU affinity, the local group can be skipped which breaks the
assumption that statistics are always collected for local group. With
uninitialized local_sgs, the comparison is meaningless and the behavior
unpredictable. This can even end up to use local pointer which is to
NULL in this case.
If the local group has been skipped because of CPU affinity, we return
the idlest group.
Fixes: 57abff067a ("sched/fair: Rework find_idlest_group()")
Reported-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: John Stultz <john.stultz@linaro.org>
Cc: rostedt@goodmis.org
Cc: valentin.schneider@arm.com
Cc: mingo@redhat.com
Cc: mgorman@suse.de
Cc: juri.lelli@redhat.com
Cc: dietmar.eggemann@arm.com
Cc: bsegall@google.com
Cc: qais.yousef@arm.com
Link: https://lkml.kernel.org/r/1575483700-22153-1-git-send-email-vincent.guittot@linaro.org
The psi window size is a u64 an can be up to 10 seconds right now,
which exceeds the lower 32 bits of the variable. We currently use
div_u64 for it, which is meant only for 32-bit divisors. The result is
garbage pressure sampling values and even potential div0 crashes.
Use div64_u64.
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Cc: Jingfeng Xie <xiejingfeng@linux.alibaba.com>
Link: https://lkml.kernel.org/r/20191203183524.41378-3-hannes@cmpxchg.org
Jingfeng reports rare div0 crashes in psi on systems with some uptime:
[58914.066423] divide error: 0000 [#1] SMP
[58914.070416] Modules linked in: ipmi_poweroff ipmi_watchdog toa overlay fuse tcp_diag inet_diag binfmt_misc aisqos(O) aisqos_hotfixes(O)
[58914.083158] CPU: 94 PID: 140364 Comm: kworker/94:2 Tainted: G W OE K 4.9.151-015.ali3000.alios7.x86_64 #1
[58914.093722] Hardware name: Alibaba Alibaba Cloud ECS/Alibaba Cloud ECS, BIOS 3.23.34 02/14/2019
[58914.102728] Workqueue: events psi_update_work
[58914.107258] task: ffff8879da83c280 task.stack: ffffc90059dcc000
[58914.113336] RIP: 0010:[] [] psi_update_stats+0x1c1/0x330
[58914.122183] RSP: 0018:ffffc90059dcfd60 EFLAGS: 00010246
[58914.127650] RAX: 0000000000000000 RBX: ffff8858fe98be50 RCX: 000000007744d640
[58914.134947] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00003594f700648e
[58914.142243] RBP: ffffc90059dcfdf8 R08: 0000359500000000 R09: 0000000000000000
[58914.149538] R10: 0000000000000000 R11: 0000000000000000 R12: 0000359500000000
[58914.156837] R13: 0000000000000000 R14: 0000000000000000 R15: ffff8858fe98bd78
[58914.164136] FS: 0000000000000000(0000) GS:ffff887f7f380000(0000) knlGS:0000000000000000
[58914.172529] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[58914.178467] CR2: 00007f2240452090 CR3: 0000005d5d258000 CR4: 00000000007606f0
[58914.185765] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[58914.193061] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[58914.200360] PKRU: 55555554
[58914.203221] Stack:
[58914.205383] ffff8858fe98bd48 00000000000002f0 0000002e81036d09 ffffc90059dcfde8
[58914.213168] ffff8858fe98bec8 0000000000000000 0000000000000000 0000000000000000
[58914.220951] 0000000000000000 0000000000000000 0000000000000000 0000000000000000
[58914.228734] Call Trace:
[58914.231337] [] psi_update_work+0x22/0x60
[58914.237067] [] process_one_work+0x189/0x420
[58914.243063] [] worker_thread+0x4e/0x4b0
[58914.248701] [] ? process_one_work+0x420/0x420
[58914.254869] [] kthread+0xe6/0x100
[58914.259994] [] ? kthread_park+0x60/0x60
[58914.265640] [] ret_from_fork+0x39/0x50
[58914.271193] Code: 41 29 c3 4d 39 dc 4d 0f 42 dc <49> f7 f1 48 8b 13 48 89 c7 48 c1
[58914.279691] RIP [] psi_update_stats+0x1c1/0x330
The crashing instruction is trying to divide the observed stall time
by the sampling period. The period, stored in R8, is not 0, but we are
dividing by the lower 32 bits only, which are all 0 in this instance.
We could switch to a 64-bit division, but the period shouldn't be that
big in the first place. It's the time between the last update and the
next scheduled one, and so should always be around 2s and comfortably
fit into 32 bits.
The bug is in the initialization of new cgroups: we schedule the first
sampling event in a cgroup as an offset of sched_clock(), but fail to
initialize the last_update timestamp, and it defaults to 0. That
results in a bogusly large sampling period the first time we run the
sampling code, and consequently we underreport pressure for the first
2s of a cgroup's life. But worse, if sched_clock() is sufficiently
advanced on the system, and the user gets unlucky, the period's lower
32 bits can all be 0 and the sampling division will crash.
Fix this by initializing the last update timestamp to the creation
time of the cgroup, thus correctly marking the start of the first
pressure sampling period in a new cgroup.
Reported-by: Jingfeng Xie <xiejingfeng@linux.alibaba.com>
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Suren Baghdasaryan <surenb@google.com>
Link: https://lkml.kernel.org/r/20191203183524.41378-2-hannes@cmpxchg.org
Since commit
28875945ba ("rcu: Add support for consolidated-RCU reader checking")
there is an additional check to ensure that a RCU related lock is held
while the RCU list is iterated.
This section holds the SRCU reader lock instead.
Add annotation to list_for_each_entry_rcu() that pmus_srcu must be
acquired during the list traversal.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lkml.kernel.org/r/20191119121429.zhcubzdhm672zasg@linutronix.de
Commit da765a2f59 ("bpf: Add poke dependency tracking for prog array
maps") wrongly assumed that in case of prog load errors, we're cleaning
up all program tracking via bpf_free_used_maps().
However, it can happen that we're still at the point where we didn't copy
map pointers into the prog's aux section such that env->prog->aux->used_maps
is still zero, running into a UAF. In such case, the verifier has similar
release_maps() helper that drops references to used maps from its env.
Consolidate the release code into __bpf_free_used_maps() and call it from
all sides to fix it.
Fixes: da765a2f59 ("bpf: Add poke dependency tracking for prog array maps")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/1c2909484ca524ae9f55109b06f22b6213e76376.1576514756.git.daniel@iogearbox.net
-----BEGIN PGP SIGNATURE-----
Comment: Kees Cook <kees@outflux.net>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=YU4A
-----END PGP SIGNATURE-----
Merge tag 'sizeof_field-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull FIELD_SIZEOF conversion from Kees Cook:
"A mostly mechanical treewide conversion from FIELD_SIZEOF() to
sizeof_field(). This avoids the redundancy of having 2 macros
(actually 3) doing the same thing, and consolidates on sizeof_field().
While "field" is not an accurate name, it is the common name used in
the kernel, and doesn't result in any unintended innuendo.
As there are still users of FIELD_SIZEOF() in -next, I will clean up
those during this coming development cycle and send the final old
macro removal patch at that time"
* tag 'sizeof_field-v5.5-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
treewide: Use sizeof_field() macro
MIPS: OCTEON: Replace SIZEOF_FIELD() macro
This commit adds a BPF dispatcher for XDP. The dispatcher is updated
from the XDP control-path, dev_xdp_install(), and used when an XDP
program is run via bpf_prog_run_xdp().
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191213175112.30208-4-bjorn.topel@gmail.com
The BPF dispatcher is a multi-way branch code generator, mainly
targeted for XDP programs. When an XDP program is executed via the
bpf_prog_run_xdp(), it is invoked via an indirect call. The indirect
call has a substantial performance impact, when retpolines are
enabled. The dispatcher transform indirect calls to direct calls, and
therefore avoids the retpoline. The dispatcher is generated using the
BPF JIT, and relies on text poking provided by bpf_arch_text_poke().
The dispatcher hijacks a trampoline function it via the __fentry__ nop
of the trampoline. One dispatcher instance currently supports up to 64
dispatch points. A user creates a dispatcher with its corresponding
trampoline with the DEFINE_BPF_DISPATCHER macro.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191213175112.30208-3-bjorn.topel@gmail.com
Refactor the image allocation in the BPF trampoline code into a
separate function, so it can be shared with the BPF dispatcher in
upcoming commits.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191213175112.30208-2-bjorn.topel@gmail.com
Each of rcu_state, rcu_rnp_online_cpus(), rcu_dynticks_curr_cpu_in_eqs(),
and rcu_dynticks_snap() are used only in the kernel/rcu/tree.o translation
unit, and may thus be marked static. This commit therefore makes this
change.
Reported-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The scheduler code calling cpufreq_update_util() may run during CPU
offline on the target CPU after the IRQ work lists have been flushed
for it, so the target CPU should be prevented from running code that
may queue up an IRQ work item on it at that point.
Unfortunately, that may not be the case if dvfs_possible_from_any_cpu
is set for at least one cpufreq policy in the system, because that
allows the CPU going offline to run the utilization update callback
of the cpufreq governor on behalf of another (online) CPU in some
cases.
If that happens, the cpufreq governor callback may queue up an IRQ
work on the CPU running it, which is going offline, and the IRQ work
may not be flushed after that point. Moreover, that IRQ work cannot
be flushed until the "offlining" CPU goes back online, so if any
other CPU calls irq_work_sync() to wait for the completion of that
IRQ work, it will have to wait until the "offlining" CPU is back
online and that may not happen forever. In particular, a system-wide
deadlock may occur during CPU online as a result of that.
The failing scenario is as follows. CPU0 is the boot CPU, so it
creates a cpufreq policy and becomes the "leader" of it
(policy->cpu). It cannot go offline, because it is the boot CPU.
Next, other CPUs join the cpufreq policy as they go online and they
leave it when they go offline. The last CPU to go offline, say CPU3,
may queue up an IRQ work while running the governor callback on
behalf of CPU0 after leaving the cpufreq policy because of the
dvfs_possible_from_any_cpu effect described above. Then, CPU0 is
the only online CPU in the system and the stale IRQ work is still
queued on CPU3. When, say, CPU1 goes back online, it will run
irq_work_sync() to wait for that IRQ work to complete and so it
will wait for CPU3 to go back online (which may never happen even
in principle), but (worse yet) CPU0 is waiting for CPU1 at that
point too and a system-wide deadlock occurs.
To address this problem notice that CPUs which cannot run cpufreq
utilization update code for themselves (for example, because they
have left the cpufreq policies that they belonged to), should also
be prevented from running that code on behalf of the other CPUs that
belong to a cpufreq policy with dvfs_possible_from_any_cpu set and so
in that case the cpufreq_update_util_data pointer of the CPU running
the code must not be NULL as well as for the CPU which is the target
of the cpufreq utilization update in progress.
Accordingly, change cpufreq_this_cpu_can_update() into a regular
function in kernel/sched/cpufreq.c (instead of a static inline in a
header file) and make it check the cpufreq_update_util_data pointer
of the local CPU if dvfs_possible_from_any_cpu is set for the target
cpufreq policy.
Also update the schedutil governor to do the
cpufreq_this_cpu_can_update() check in the non-fast-switch
case too to avoid the stale IRQ work issues.
Fixes: 99d14d0e16 ("cpufreq: Process remote callbacks from any CPU if the platform permits")
Link: https://lore.kernel.org/linux-pm/20191121093557.bycvdo4xyinbc5cb@vireshk-i7/
Reported-by: Anson Huang <anson.huang@nxp.com>
Tested-by: Anson Huang <anson.huang@nxp.com>
Cc: 4.14+ <stable@vger.kernel.org> # 4.14+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Tested-by: Peng Fan <peng.fan@nxp.com> (i.MX8QXP-MEK)
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After Spectre 2 fix via 290af86629 ("bpf: introduce BPF_JIT_ALWAYS_ON
config") most major distros use BPF_JIT_ALWAYS_ON configuration these days
which compiles out the BPF interpreter entirely and always enables the
JIT. Also given recent fix in e1608f3fa8 ("bpf: Avoid setting bpf insns
pages read-only when prog is jited"), we additionally avoid fragmenting
the direct map for the BPF insns pages sitting in the general data heap
since they are not used during execution. Latter is only needed when run
through the interpreter.
Since both x86 and arm64 JITs have seen a lot of exposure over the years,
are generally most up to date and maintained, there is more downside in
!BPF_JIT_ALWAYS_ON configurations to have the interpreter enabled by default
rather than the JIT. Add a ARCH_WANT_DEFAULT_BPF_JIT config which archs can
use to set the bpf_jit_{enable,kallsyms} to 1. Back in the days the
bpf_jit_kallsyms knob was set to 0 by default since major distros still
had /proc/kallsyms addresses exposed to unprivileged user space which is
not the case anymore. Hence both knobs are set via BPF_JIT_DEFAULT_ON which
is set to 'y' in case of BPF_JIT_ALWAYS_ON or ARCH_WANT_DEFAULT_BPF_JIT.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Will Deacon <will@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/f78ad24795c2966efcc2ee19025fa3459f622185.1575903816.git.daniel@iogearbox.net
Make BPF trampoline attach its generated assembly code to kernel functions via
register_ftrace_direct() API. It helps ftrace-based tracers co-exist with BPF
trampoline on the same kernel function. It also switches attaching logic from
arch specific text_poke to generic ftrace that is available on many
architectures. text_poke is still necessary for bpf-to-bpf attach and for
bpf_tail_call optimization.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191209000114.1876138-3-ast@kernel.org
- Removal of code I accidentally applied when doing a minor fix up
to a patch, and then using "git commit -a --amend", which pulled
in some other changes I was playing with.
- Remove an used variable in trace_events_inject code
- Fix to function graph tracer when it traces a ftrace direct function.
It will now ignore tracing a function that has a ftrace direct
tramploine attached. This is needed for eBPF to use the ftrace direct
code.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXfD/thQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qoo2AP4j7ONw7BTmMyo+GdYqPPntBeDnClHK
vfMKrgK1j5BxYgEA7LgkwuUT9bcyLjfJVcyfeW67rB2PtmovKTWnKihFOwI=
=DZ6N
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
- Remove code I accidentally applied when doing a minor fix up to a
patch, and then using "git commit -a --amend", which pulled in some
other changes I was playing with.
- Remove an used variable in trace_events_inject code
- Fix function graph tracer when it traces a ftrace direct function.
It will now ignore tracing a function that has a ftrace direct
tramploine attached. This is needed for eBPF to use the ftrace direct
code.
* tag 'trace-v5.5-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace: Fix function_graph tracer interaction with BPF trampoline
tracing: remove set but not used variable 'buffer'
module: Remove accidental change of module_enable_x()
Allow for audit messages to be emitted upon BPF program load and
unload for having a timeline of events. The load itself is in
syscall context, so additional info about the process initiating
the BPF prog creation can be logged and later directly correlated
to the unload event.
The only info really needed from BPF side is the globally unique
prog ID where then audit user space tooling can query / dump all
info needed about the specific BPF program right upon load event
and enrich the record, thus these changes needed here can be kept
small and non-intrusive to the core.
Raw example output:
# auditctl -D
# auditctl -a always,exit -F arch=x86_64 -S bpf
# ausearch --start recent -m 1334
...
----
time->Wed Nov 27 16:04:13 2019
type=PROCTITLE msg=audit(1574867053.120:84664): proctitle="./bpf"
type=SYSCALL msg=audit(1574867053.120:84664): arch=c000003e syscall=321 \
success=yes exit=3 a0=5 a1=7ffea484fbe0 a2=70 a3=0 items=0 ppid=7477 \
pid=12698 auid=1001 uid=1001 gid=1001 euid=1001 suid=1001 fsuid=1001 \
egid=1001 sgid=1001 fsgid=1001 tty=pts2 ses=4 comm="bpf" \
exe="/home/jolsa/auditd/audit-testsuite/tests/bpf/bpf" \
subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
type=UNKNOWN[1334] msg=audit(1574867053.120:84664): prog-id=76 op=LOAD
----
time->Wed Nov 27 16:04:13 2019
type=UNKNOWN[1334] msg=audit(1574867053.120:84665): prog-id=76 op=UNLOAD
...
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Co-developed-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Paul Moore <paul@paul-moore.com>
Link: https://lore.kernel.org/bpf/20191206214934.11319-1-jolsa@kernel.org
Building with -Werror showed another failure:
kernel/bpf/btf.c: In function 'btf_get_prog_ctx_type.isra.31':
kernel/bpf/btf.c:3508:63: error: array subscript 0 is above array bounds of 'u8[0]' {aka 'unsigned char[0]'} [-Werror=array-bounds]
ctx_type = btf_type_member(conv_struct) + bpf_ctx_convert_map[prog_type] * 2;
I don't actually understand why the array is empty, but a similar
fix has addressed a related problem, so I suppose we can do the
same thing here.
Fixes: ce27709b81 ("bpf: Fix build in minimal configurations")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191210203553.2941035-1-arnd@arndb.de
Remove references to unused functions, standardize language, update to
reflect new functionality, migrate to rst format, and fix all kernel-doc
warnings.
Fixes: 815613da6a ("kernel/padata.c: removed unused code")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
reorder_objects is unused since the rework of padata's flushing, so
remove it.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Since commit 63d3578892 ("crypto: pcrypt - remove padata cpumask
notifier") this feature is unused, so get rid of it.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
lockdep complains when padata's paths to update cpumasks via CPU hotplug
and sysfs are both taken:
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo ff > /sys/kernel/pcrypt/pencrypt/parallel_cpumask
======================================================
WARNING: possible circular locking dependency detected
5.4.0-rc8-padata-cpuhp-v3+ #1 Not tainted
------------------------------------------------------
bash/205 is trying to acquire lock:
ffffffff8286bcd0 (cpu_hotplug_lock.rw_sem){++++}, at: padata_set_cpumask+0x2b/0x120
but task is already holding lock:
ffff8880001abfa0 (&pinst->lock){+.+.}, at: padata_set_cpumask+0x26/0x120
which lock already depends on the new lock.
padata doesn't take cpu_hotplug_lock and pinst->lock in a consistent
order. Which should be first? CPU hotplug calls into padata with
cpu_hotplug_lock already held, so it should have priority.
Fixes: 6751fb3c0e ("padata: Use get_online_cpus/put_online_cpus")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Configuring an instance's parallel mask without any online CPUs...
echo 2 > /sys/kernel/pcrypt/pencrypt/parallel_cpumask
echo 0 > /sys/devices/system/cpu/cpu1/online
...makes tcrypt mode=215 crash like this:
divide error: 0000 [#1] SMP PTI
CPU: 4 PID: 283 Comm: modprobe Not tainted 5.4.0-rc8-padata-doc-v2+ #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20191013_105130-anatol 04/01/2014
RIP: 0010:padata_do_parallel+0x114/0x300
Call Trace:
pcrypt_aead_encrypt+0xc0/0xd0 [pcrypt]
crypto_aead_encrypt+0x1f/0x30
do_mult_aead_op+0x4e/0xdf [tcrypt]
test_mb_aead_speed.constprop.0.cold+0x226/0x564 [tcrypt]
do_test+0x28c2/0x4d49 [tcrypt]
tcrypt_mod_init+0x55/0x1000 [tcrypt]
...
cpumask_weight() in padata_cpu_hash() returns 0 because the mask has no
CPUs. The problem is __padata_remove_cpu() checks for valid masks too
early and so doesn't mark the instance PADATA_INVALID as expected, which
would have made padata_do_parallel() return error before doing the
division.
Fix by introducing a second padata CPU hotplug state before
CPUHP_BRINGUP_CPU so that __padata_remove_cpu() sees the online mask
without @cpu. No need for the second argument to padata_replace() since
@cpu is now already missing from the online mask.
Fixes: 33e5445068 ("padata: Handle empty padata cpumasks")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Eric Biggers <ebiggers@kernel.org>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
If the pcrypt template is used multiple times in an algorithm, then a
deadlock occurs because all pcrypt instances share the same
padata_instance, which completes requests in the order submitted. That
is, the inner pcrypt request waits for the outer pcrypt request while
the outer request is already waiting for the inner.
This patch fixes this by allocating a set of queues for each pcrypt
instance instead of using two global queues. In order to maintain
the existing user-space interface, the pinst structure remains global
so any sysfs modifications will apply to every pcrypt instance.
Note that when an update occurs we have to allocate memory for
every pcrypt instance. Should one of the allocations fail we
will abort the update without rolling back changes already made.
The new per-instance data structure is called padata_shell and is
essentially a wrapper around parallel_data.
Reproducer:
#include <linux/if_alg.h>
#include <sys/socket.h>
#include <unistd.h>
int main()
{
struct sockaddr_alg addr = {
.salg_type = "aead",
.salg_name = "pcrypt(pcrypt(rfc4106-gcm-aesni))"
};
int algfd, reqfd;
char buf[32] = { 0 };
algfd = socket(AF_ALG, SOCK_SEQPACKET, 0);
bind(algfd, (void *)&addr, sizeof(addr));
setsockopt(algfd, SOL_ALG, ALG_SET_KEY, buf, 20);
reqfd = accept(algfd, 0, 0);
write(reqfd, buf, 32);
read(reqfd, buf, 16);
}
Reported-by: syzbot+56c7151cad94eec37c521f0e47d2eee53f9361c4@syzkaller.appspotmail.com
Fixes: 5068c7a883 ("crypto: pcrypt - Add pcrypt crypto parallelization wrapper")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function padata_remove_cpu was supposed to have been removed
along with padata_add_cpu but somehow it remained behind. Let's
kill it now as it doesn't even have a prototype anymore.
Fixes: 815613da6a ("kernel/padata.c: removed unused code")
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function padata_flush_queues is fundamentally broken because
it cannot force padata users to complete the request that is
underway. IOW padata has to passively wait for the completion
of any outstanding work.
As it stands flushing is used in two places. Its use in padata_stop
is simply unnecessary because nothing depends on the queues to
be flushed afterwards.
The other use in padata_replace is more substantial as we depend
on it to free the old pd structure. This patch instead uses the
pd->refcnt to dynamically free the pd structure once all requests
are complete.
Fixes: 2b73b07ab8 ("padata: Flush the padata queues actively")
Cc: <stable@vger.kernel.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
This ended up causing some noise in places such as rxrpc running in softirq.
The warning is misleading in this case as the mutex trylock and unlock
operations are done within the same context; and therefore we need not
worry about the PI-boosting issues that comes along with no single-owner
lock guarantees.
While we don't want to support this in mutexes, there is no way out of
this yet; so lets get rid of the WARNs for now, as it is only fair to
code that has historically relied on non-preemptible softirq guarantees.
In addition, changing the lock type is also unviable: exclusive rwsems
have the same issue (just not the WARN_ON) and counting semaphores
would introduce a performance hit as mutexes are a lot more optimized.
This reverts:
a0855d24fc: ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
Fixes: a0855d24fc: ("locking/mutex: Complain upon mutex API misuse in IRQ contexts")
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: David Howells <dhowells@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-afs@lists.infradead.org
Cc: linux-fsdevel@vger.kernel.org
Cc: will@kernel.org
Link: https://lkml.kernel.org/r/20191210220523.28540-1-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Depending on type of BPF programs served by BPF trampoline it can call original
function. In such case the trampoline will skip one stack frame while
returning. That will confuse function_graph tracer and will cause crashes with
bad RIP. Teach graph tracer to skip functions that have BPF trampoline attached.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
kernel/trace/trace_events_inject.c: In function trace_inject_entry:
kernel/trace/trace_events_inject.c:20:22: warning: variable buffer set but not used [-Wunused-but-set-variable]
It is never used, so remove it.
Link: http://lkml.kernel.org/r/20191207034409.25668-1-yuehaibing@huawei.com
Reported-by: Hulk Robot <hulkci@huawei.com>
Acked-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When pulling in Divya Indi's patch, I made a minor fix to remove unneeded
braces. I commited my fix up via "git commit -a --amend". Unfortunately, I
didn't realize I had some changes I was testing in the module code, and
those changes were applied to Divya's patch as well.
This reverts the accidental updates to the module code.
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Divya Indi <divya.indi@oracle.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Fixes: e585e6469d ("tracing: Verify if trace array exists before destroying it.")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This commit switches from static structure to dynamic allocation
for rcu_fwds as another step towards providing multiple call_rcu()
forward-progress kthreads.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit threads pointers to rcu_fwd structures through the remaining
functions using rcu_fwds directly, namely rcu_torture_fwd_prog_cbfree(),
rcutorture_oom_notify() and rcu_torture_fwd_prog_init().
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In order to add multiple call_rcu() forward-progress kthreads, it will
be necessary to dynamically allocate and initialize. This commit
therefore moves the initialization from compile time to instead
immediately precede thread-creation time.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In order to add multiple kthreads, it will be necessary to allow
the various functions to operate on a pointer to their kthread's
rcu_fwd structure. This commit therefore starts the process of
adding the needed "struct rcu_fwd" parameters and arguments to the
various callback forward-progress functions.
Note that rcutorture_oom_notify() and rcu_torture_fwd_cb_hist() will
eventually need to iterate over all kthreads' rcu_fwd structures.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that RCU behaves reasonably well with the current single-kthread
call_rcu() forward-progress testing, it is time to add more kthreads.
This commit takes a first step towards that goal by wrapping what
will be the per-kthread data into a new rcu_fwd structure.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The config option `CONFIG_PREEMPT' is used for the preemption model
"Low-Latency Desktop". The config option `CONFIG_PREEMPTION' is enabled
when kernel preemption is enabled which is true for the preemption model
`CONFIG_PREEMPT' and `CONFIG_PREEMPT_RT'.
Use `CONFIG_PREEMPTION' if it applies to both preemption models and not
just to `CONFIG_PREEMPT'.
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: rcu@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently PREEMPT_RCU and TREE_RCU are mutually exclusive Kconfig
options. But PREEMPT_RCU actually specifies a kind of TREE_RCU,
namely a preemptible TREE_RCU. This commit therefore makes PREEMPT_RCU
be a modifer to the TREE_RCU Kconfig option. This has the benefit of
simplifying several of the #if expressions that formerly needed to
check both, but now need only check one or the other.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Lai Jiangshan <jiangshanlai@gmail.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_preempt_check_blocked_tasks() function has a comment
that states that the rcu_node structure's ->lock must be held,
which might be informative, but which carries little weight if
not read. This commit therefore removes this comment in favor of
raw_lockdep_assert_held_rcu_node(), which will complain quite
visibly if the required lock is not held.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_gp_fqs_check_wake() function uses rcu_preempt_blocked_readers_cgp()
to read ->gp_tasks while other cpus might overwrite this field.
We need READ_ONCE()/WRITE_ONCE() pairs to avoid compiler
tricks and KCSAN splats like the following :
BUG: KCSAN: data-race in rcu_gp_fqs_check_wake / rcu_preempt_deferred_qs_irqrestore
write to 0xffffffff85a7f190 of 8 bytes by task 7317 on cpu 0:
rcu_preempt_deferred_qs_irqrestore+0x43d/0x580 kernel/rcu/tree_plugin.h:507
rcu_read_unlock_special+0xec/0x370 kernel/rcu/tree_plugin.h:659
__rcu_read_unlock+0xcf/0xe0 kernel/rcu/tree_plugin.h:394
rcu_read_unlock include/linux/rcupdate.h:645 [inline]
__ip_queue_xmit+0x3b0/0xa40 net/ipv4/ip_output.c:533
ip_queue_xmit+0x45/0x60 include/net/ip.h:236
__tcp_transmit_skb+0xdeb/0x1cd0 net/ipv4/tcp_output.c:1158
__tcp_send_ack+0x246/0x300 net/ipv4/tcp_output.c:3685
tcp_send_ack+0x34/0x40 net/ipv4/tcp_output.c:3691
tcp_cleanup_rbuf+0x130/0x360 net/ipv4/tcp.c:1575
tcp_recvmsg+0x633/0x1a30 net/ipv4/tcp.c:2179
inet_recvmsg+0xbb/0x250 net/ipv4/af_inet.c:838
sock_recvmsg_nosec net/socket.c:871 [inline]
sock_recvmsg net/socket.c:889 [inline]
sock_recvmsg+0x92/0xb0 net/socket.c:885
sock_read_iter+0x15f/0x1e0 net/socket.c:967
call_read_iter include/linux/fs.h:1864 [inline]
new_sync_read+0x389/0x4f0 fs/read_write.c:414
read to 0xffffffff85a7f190 of 8 bytes by task 10 on cpu 1:
rcu_gp_fqs_check_wake kernel/rcu/tree.c:1556 [inline]
rcu_gp_fqs_check_wake+0x93/0xd0 kernel/rcu/tree.c:1546
rcu_gp_fqs_loop+0x36c/0x580 kernel/rcu/tree.c:1611
rcu_gp_kthread+0x143/0x220 kernel/rcu/tree.c:1768
kthread+0x1d4/0x200 drivers/block/aoe/aoecmd.c:1253
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352
Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 10 Comm: rcu_preempt Not tainted 5.3.0+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
[ paulmck: Added another READ_ONCE() for RCU CPU stall warnings. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Commit 18cd8c93e6 ("rcu/nocb: Print gp/cb kthread hierarchy if
dump_tree") added print statements to rcu_organize_nocb_kthreads for
debugging, but incorrectly guarded them, causing the function to always
spew out its message.
This patch fixes it by guarding both pr_alert statements with dump_tree,
while also changing the second pr_alert to a pr_cont, to print the
hierarchy in a single line (assuming that's how it was supposed to
work).
Fixes: 18cd8c93e6 ("rcu/nocb: Print gp/cb kthread hierarchy if dump_tree")
Signed-off-by: Stefan Reiter <stefan@pimaker.at>
[ paulmck: Make single-nocbs-CPU GP kthreads look less erroneous. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
An expedited grace period can be stalled by a nohz_full CPU looping
in kernel context. This possibility is currently handled by some
carefully crafted checks in rcu_read_unlock_special() that enlist help
from ksoftirqd when permitted by the scheduler. However, it is exactly
these checks that require the scheduler avoid holding any of its rq or
pi locks across rcu_read_unlock() without also having held them across
the entire RCU read-side critical section.
It would therefore be very nice if expedited grace periods could
handle nohz_full CPUs looping in kernel context without such checks.
This commit therefore adds code to the expedited grace period's wait
and cleanup code that forces the scheduler-clock interrupt on for CPUs
that fail to quickly supply a quiescent state. "Quickly" is currently
a hard-coded single-jiffy delay.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
After RCU flavor consolidation, synchronize_sched_expedited_wait() does
both RCU-preempt and RCU-sched, whichever happens to have been built into
the running kernel. This commit therefore changes this function's name
to synchronize_rcu_expedited_wait() to reflect its new generic nature.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The function-header comments in kernel/rcu/tree_exp.h have gotten a bit
out of date, so this commit updates a number of them.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Now that the RCU flavors have been consolidated, there is one common
function for checking to see if an expedited RCU grace period has
completed, namely sync_rcu_preempt_exp_done(). Because this function is
no longer specific to RCU-preempt, this commit removes the "_preempt" from
its name. This commit also changes sync_rcu_preempt_exp_done_unlocked()
to sync_rcu_exp_done_unlocked() for the same reason.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The current expedited RCU grace-period code expects that a task
requesting an expedited grace period cannot awaken until that grace
period has reached the wakeup phase. However, it is possible for a long
preemption to result in the waiting task never sleeping. For example,
consider the following sequence of events:
1. Task A starts an expedited grace period by invoking
synchronize_rcu_expedited(). It proceeds normally up to the
wait_event() near the end of that function, and is then preempted
(or interrupted or whatever).
2. The expedited grace period completes, and a kworker task starts
the awaken phase, having incremented the counter and acquired
the rcu_state structure's .exp_wake_mutex. This kworker task
is then preempted or interrupted or whatever.
3. Task A resumes and enters wait_event(), which notes that the
expedited grace period has completed, and thus doesn't sleep.
4. Task B starts an expedited grace period exactly as did Task A,
complete with the preemption (or whatever delay) just before
the call to wait_event().
5. The expedited grace period completes, and another kworker
task starts the awaken phase, having incremented the counter.
However, it blocks when attempting to acquire the rcu_state
structure's .exp_wake_mutex because step 2's kworker task has
not yet released it.
6. Steps 4 and 5 repeat, resulting in overflow of the rcu_node
structure's ->exp_wq[] array.
In theory, this is harmless. Tasks waiting on the various ->exp_wq[]
array will just be spuriously awakened, but they will just sleep again
on noting that the rcu_state structure's ->expedited_sequence value has
not advanced far enough.
In practice, this wastes CPU time and is an accident waiting to happen.
This commit therefore moves the rcu_exp_gp_seq_end() call that officially
ends the expedited grace period (along with associate tracing) until
after the ->exp_wake_mutex has been acquired. This prevents Task A from
awakening prematurely, thus preventing more than one expedited grace
period from being in flight during a previous expedited grace period's
wakeup phase.
Fixes: 3b5f668e71 ("rcu: Overlap wakeups with next expedited grace period")
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
[ paulmck: Added updated comment. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Tasks waiting within exp_funnel_lock() for an expedited grace period to
elapse can be starved due to the following sequence of events:
1. Tasks A and B both attempt to start an expedited grace
period at about the same time. This grace period will have
completed when the lower four bits of the rcu_state structure's
->expedited_sequence field are 0b'0100', for example, when the
initial value of this counter is zero. Task A wins, and thus
does the actual work of starting the grace period, including
acquiring the rcu_state structure's .exp_mutex and sets the
counter to 0b'0001'.
2. Because task B lost the race to start the grace period, it
waits on ->expedited_sequence to reach 0b'0100' inside of
exp_funnel_lock(). This task therefore blocks on the rcu_node
structure's ->exp_wq[1] field, keeping in mind that the
end-of-grace-period value of ->expedited_sequence (0b'0100')
is shifted down two bits before indexing the ->exp_wq[] field.
3. Task C attempts to start another expedited grace period,
but blocks on ->exp_mutex, which is still held by Task A.
4. The aforementioned expedited grace period completes, so that
->expedited_sequence now has the value 0b'0100'. A kworker task
therefore acquires the rcu_state structure's ->exp_wake_mutex
and starts awakening any tasks waiting for this grace period.
5. One of the first tasks awakened happens to be Task A. Task A
therefore releases the rcu_state structure's ->exp_mutex,
which allows Task C to start the next expedited grace period,
which causes the lower four bits of the rcu_state structure's
->expedited_sequence field to become 0b'0101'.
6. Task C's expedited grace period completes, so that the lower four
bits of the rcu_state structure's ->expedited_sequence field now
become 0b'1000'.
7. The kworker task from step 4 above continues its wakeups.
Unfortunately, the wake_up_all() refetches the rcu_state
structure's .expedited_sequence field:
wake_up_all(&rnp->exp_wq[rcu_seq_ctr(rcu_state.expedited_sequence) & 0x3]);
This results in the wakeup being applied to the rcu_node
structure's ->exp_wq[2] field, which is unfortunate given that
Task B is instead waiting on ->exp_wq[1].
On a busy system, no harm is done (or at least no permanent harm is done).
Some later expedited grace period will redo the wakeup. But on a quiet
system, such as many embedded systems, it might be a good long time before
there was another expedited grace period. On such embedded systems,
this situation could therefore result in a system hang.
This issue manifested as DPM device timeout during suspend (which
usually qualifies as a quiet time) due to a SCSI device being stuck in
_synchronize_rcu_expedited(), with the following stack trace:
schedule()
synchronize_rcu_expedited()
synchronize_rcu()
scsi_device_quiesce()
scsi_bus_suspend()
dpm_run_callback()
__device_suspend()
This commit therefore prevents such delays, timeouts, and hangs by
making rcu_exp_wait_wake() use its "s" argument consistently instead of
refetching from rcu_state.expedited_sequence.
Fixes: 3b5f668e71 ("rcu: Overlap wakeups with next expedited grace period")
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The code in sync_rcu_exp_select_node_cpus() calculates the current
CPU's mask within its rcu_node structure's bitmasks, but this has
already been computed in the ->grpmask field of that CPU's rcu_data
structure. This commit therefore just uses this ->grpmask field.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This fixes a data-race where `atomic_t dynticks` is copied by value. The
copy is performed non-atomically, resulting in a data-race if `dynticks`
is updated concurrently.
This data-race was found with KCSAN:
==================================================================
BUG: KCSAN: data-race in dyntick_save_progress_counter / rcu_irq_enter
write to 0xffff989dbdbe98e0 of 4 bytes by task 10 on cpu 3:
atomic_add_return include/asm-generic/atomic-instrumented.h:78 [inline]
rcu_dynticks_snap kernel/rcu/tree.c:310 [inline]
dyntick_save_progress_counter+0x43/0x1b0 kernel/rcu/tree.c:984
force_qs_rnp+0x183/0x200 kernel/rcu/tree.c:2286
rcu_gp_fqs kernel/rcu/tree.c:1601 [inline]
rcu_gp_fqs_loop+0x71/0x880 kernel/rcu/tree.c:1653
rcu_gp_kthread+0x22c/0x3b0 kernel/rcu/tree.c:1799
kthread+0x1b5/0x200 kernel/kthread.c:255
<snip>
read to 0xffff989dbdbe98e0 of 4 bytes by task 154 on cpu 7:
rcu_nmi_enter_common kernel/rcu/tree.c:828 [inline]
rcu_irq_enter+0xda/0x240 kernel/rcu/tree.c:870
irq_enter+0x5/0x50 kernel/softirq.c:347
<snip>
Reported by Kernel Concurrency Sanitizer on:
CPU: 7 PID: 154 Comm: kworker/7:1H Not tainted 5.3.0+ #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Workqueue: kblockd blk_mq_run_work_fn
==================================================================
Signed-off-by: Marco Elver <elver@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: rcu@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The "mask_ofl_ipi" is used to track which CPUs get IPIed, however
in the IPI sending loop, "mask_ofl_ipi" along with another variable
"mask_ofl_test" might also get modified to record which CPUs' quiesent
states must be reported by the sync_rcu_exp_select_node_cpus() at
the end of sync_rcu_exp_select_node_cpus(). This overlap of roles
can be confusing, so this patch cleans things a little by using
"mask_ofl_ipi" solely for determining which CPUs must be IPIed and
"mask_ofl_test" for solely determining on behalf of which CPUs
sync_rcu_exp_select_node_cpus() must report a quiscent state.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Acked-by: Marco Elver <elver@google.com>
The rcu_node structure's ->expmask field is accessed locklessly when
starting a new expedited grace period and when reporting an expedited
RCU CPU stall warning. This commit therefore handles the former by
taking a snapshot of ->expmask while the lock is held and the latter
by applying READ_ONCE() to lockless reads and WRITE_ONCE() to the
corresponding updates.
Link: https://lore.kernel.org/lkml/CANpmjNNmSOagbTpffHr4=Yedckx9Rm2NuGqC9UqE+AOz5f1-ZQ@mail.gmail.com
Reported-by: syzbot+134336b86f728d6e55a0@syzkaller.appspotmail.com
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Marco Elver <elver@google.com>
Add __rcu annotation to RCU-protected global pointer auditd_conn.
auditd_conn is an RCU-protected global pointer,i.e., accessed
via RCU methods rcu_dereference() and rcu_assign_pointer(),
hence it must be annotated with __rcu for sparse to report
warnings/errors correctly.
Fix multiple instances of the sparse error:
error: incompatible types in comparison expression
(different address spaces)
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Amol Grover <frextrite@gmail.com>
[PM: tweak subject line]
Signed-off-by: Paul Moore <paul@paul-moore.com>
-----BEGIN PGP SIGNATURE-----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=d5HL
-----END PGP SIGNATURE-----
Merge tag 'printk-for-5.5-pr-warning-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull pr_warning() removal from Petr Mladek.
- Final removal of the unused pr_warning() alias.
You're supposed to use just "pr_warn()" in the kernel.
* tag 'printk-for-5.5-pr-warning-removal' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
checkpatch: Drop pr_warning check
printk: Drop pr_warning definition
Fix up for "printk: Drop pr_warning definition"
workqueue: Use pr_warn instead of pr_warning
Replace all the occurrences of FIELD_SIZEOF() with sizeof_field() except
at places where these are defined. Later patches will remove the unused
definition of FIELD_SIZEOF().
This patch is generated using following script:
EXCLUDE_FILES="include/linux/stddef.h|include/linux/kernel.h"
git grep -l -e "\bFIELD_SIZEOF\b" | while read file;
do
if [[ "$file" =~ $EXCLUDE_FILES ]]; then
continue
fi
sed -i -e 's/\bFIELD_SIZEOF\b/sizeof_field/g' $file;
done
Signed-off-by: Pankaj Bharadiya <pankaj.laxminarayan.bharadiya@intel.com>
Link: https://lore.kernel.org/r/20190924105839.110713-3-pankaj.laxminarayan.bharadiya@intel.com
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Acked-by: David Miller <davem@davemloft.net> # for net
While running kprobe module test, find_module_all() caused
a suspicious RCU usage warning.
-----
=============================
WARNING: suspicious RCU usage
5.4.0-next-20191202+ #63 Not tainted
-----------------------------
kernel/module.c:619 RCU-list traversed in non-reader section!!
other info that might help us debug this:
rcu_scheduler_active = 2, debug_locks = 1
1 lock held by rmmod/642:
#0: ffffffff8227da80 (module_mutex){+.+.}, at: __x64_sys_delete_module+0x9a/0x230
stack backtrace:
CPU: 0 PID: 642 Comm: rmmod Not tainted 5.4.0-next-20191202+ #63
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.1-0-ga5cab58e9a3f-prebuilt.qemu.org 04/01/2014
Call Trace:
dump_stack+0x71/0xa0
find_module_all+0xc1/0xd0
__x64_sys_delete_module+0xac/0x230
? do_syscall_64+0x12/0x1f0
do_syscall_64+0x50/0x1f0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x4b6d49
-----
This is because list_for_each_entry_rcu(modules) is called
without rcu_read_lock(). This is safe because the module_mutex
is locked.
Pass lockdep_is_held(&module_mutex) to the list_for_each_entry_rcu()
to suppress this warning, This also fixes similar issue in
mod_find() and each_symbol_section().
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
ns_get_path() and ns_get_path_cb() only ever return either NULL or an
ERR_PTR. It is far more idiomatic to simply return an integer, and it
makes all of the callers of ns_get_path() more straightforward to read.
Fixes: e149ed2b80 ("take the targets of /proc/*/ns/* symlinks to separate fs")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Pull networking fixes from David Miller:
1) More jumbo frame fixes in r8169, from Heiner Kallweit.
2) Fix bpf build in minimal configuration, from Alexei Starovoitov.
3) Use after free in slcan driver, from Jouni Hogander.
4) Flower classifier port ranges don't work properly in the HW offload
case, from Yoshiki Komachi.
5) Use after free in hns3_nic_maybe_stop_tx(), from Yunsheng Lin.
6) Out of bounds access in mqprio_dump(), from Vladyslav Tarasiuk.
7) Fix flow dissection in dsa TX path, from Alexander Lobakin.
8) Stale syncookie timestampe fixes from Guillaume Nault.
[ Did an evil merge to silence a warning introduced by this pull - Linus ]
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (84 commits)
r8169: fix rtl_hw_jumbo_disable for RTL8168evl
net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add()
r8169: add missing RX enabling for WoL on RTL8125
vhost/vsock: accept only packets with the right dst_cid
net: phy: dp83867: fix hfs boot in rgmii mode
net: ethernet: ti: cpsw: fix extra rx interrupt
inet: protect against too small mtu values.
gre: refetch erspan header from skb->data after pskb_may_pull()
pppoe: remove redundant BUG_ON() check in pppoe_pernet
tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE()
tcp: tighten acceptance of ACKs not matching a child socket
tcp: fix rejected syncookies due to stale timestamps
lpc_eth: kernel BUG on remove
tcp: md5: fix potential overestimation of TCP option space
net: sched: allow indirect blocks to bind to clsact in TC
net: core: rename indirect block ingress cb function
net-sysfs: Call dev_hold always in netdev_queue_add_kobject
net: dsa: fix flow dissection on Tx path
net/tls: Fix return values to avoid ENOTSUPP
net: avoid an indirect call in ____sys_recvmsg()
...
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.
Update the comment to use PREEMPTION because it is true for both
preemption models.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Link: https://lore.kernel.org/r/20191015191821.11479-35-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.
Switch the Kconfig dependency to use CONFIG_PREEMPTION.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20191015191821.11479-32-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: http://lkml.kernel.org/r/20191206092503.303d6a57@canb.auug.org.au
Cc: Linux Next Mailing List <linux-next@vger.kernel.org>
Cc: Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Summary of modules changes for the 5.5 merge window:
- Refactor include/linux/export.h and remove code duplication between
EXPORT_SYMBOL and EXPORT_SYMBOL_NS to make it more readable. The most
notable change is that no namespace is represented by an empty string ""
rather than NULL.
- Fix a module load/unload race where waiter(s) trying to load the same
module weren't being woken up when a module finally goes away.
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-----BEGIN PGP SIGNATURE-----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=XDci
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:
"Summary of modules changes for the 5.5 merge window:
- Refactor include/linux/export.h and remove code duplication between
EXPORT_SYMBOL and EXPORT_SYMBOL_NS to make it more readable.
The most notable change is that no namespace is represented by an
empty string "" rather than NULL.
- Fix a module load/unload race where waiter(s) trying to load the
same module weren't being woken up when a module finally goes away"
* tag 'modules-for-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
kernel/module.c: wakeup processes in module_wq on module unload
moduleparam: fix parameter description mismatch
export: avoid code duplication in include/linux/export.h
Pull thermal management updates from Zhang Rui:
- Fix a deadlock regression in thermal core framework, which was
introduced in 5.3 (Wei Wang)
- Initialize thermal control framework earlier to enable thermal
mitigation during boot (Amit Kucheria)
- Convert the Intelligent Power Allocator (IPA) thermal governor to
follow the generic PM_EM instead of its own Energy Model (Quentin
Perret)
- Introduce a new Amlogic soc thermal driver (Guillaume La Roque)
- Add interrupt support for tsens thermal driver (Amit Kucheria)
- Add support for MSM8956/8976 in tsens thermal driver
(AngeloGioacchino Del Regno)
- Add support for r8a774b1 in rcar thermal driver (Biju Das)
- Add support for Thermal Monitor Unit v2 in qoriq thermal driver
(Yuantian Tang)
- Some other fixes/cleanups on thermal core framework and soc thermal
drivers (Colin Ian King, Daniel Lezcano, Hsin-Yi Wang, Tian Tao)
* 'thermal/next' of git://git.kernel.org/pub/scm/linux/kernel/git/thermal/linux: (32 commits)
thermal: Fix deadlock in thermal thermal_zone_device_check
thermal: cpu_cooling: Migrate to using the EM framework
thermal: cpu_cooling: Make the power-related code depend on IPA
PM / EM: Declare EM data types unconditionally
arm64: defconfig: Enable CONFIG_ENERGY_MODEL
drivers: thermal: tsens: fix potential integer overflow on multiply
thermal: cpu_cooling: Reorder the header file
thermal: cpu_cooling: Remove pointless dependency on CONFIG_OF
thermal: no need to set .owner when using module_platform_driver
thermal: qcom: tsens-v1: Fix kfree of a non-pointer value
cpufreq: qcom-hw: Move driver initialization earlier
clk: qcom: Initialize clock drivers earlier
cpufreq: Initialize cpufreq-dt driver earlier
cpufreq: Initialize the governors in core_initcall
thermal: Initialize thermal subsystem earlier
thermal: Remove netlink support
dt: thermal: tsens: Document compatible for MSM8976/56
thermal: qcom: tsens-v1: Add support for MSM8956 and MSM8976
MAINTAINERS: add entry for Amlogic Thermal driver
thermal: amlogic: Add thermal driver to support G12 SoCs
...
Merge more updates from Andrew Morton:
"Most of the rest of MM and various other things. Some Kconfig rework
still awaits merges of dependent trees from linux-next.
Subsystems affected by this patch series: mm/hotfixes, mm/memcg,
mm/vmstat, mm/thp, procfs, sysctl, misc, notifiers, core-kernel,
bitops, lib, checkpatch, epoll, binfmt, init, rapidio, uaccess, kcov,
ubsan, ipc, bitmap, mm/pagemap"
* akpm: (86 commits)
mm: remove __ARCH_HAS_4LEVEL_HACK and include/asm-generic/4level-fixup.h
um: add support for folded p4d page tables
um: remove unused pxx_offset_proc() and addr_pte() functions
sparc32: use pgtable-nopud instead of 4level-fixup
parisc/hugetlb: use pgtable-nopXd instead of 4level-fixup
parisc: use pgtable-nopXd instead of 4level-fixup
nds32: use pgtable-nopmd instead of 4level-fixup
microblaze: use pgtable-nopmd instead of 4level-fixup
m68k: mm: use pgtable-nopXd instead of 4level-fixup
m68k: nommu: use pgtable-nopud instead of 4level-fixup
c6x: use pgtable-nopud instead of 4level-fixup
arm: nommu: use pgtable-nopud instead of 4level-fixup
alpha: use pgtable-nopud instead of 4level-fixup
gpio: pca953x: tighten up indentation
gpio: pca953x: convert to use bitmap API
gpio: pca953x: use input from regs structure in pca953x_irq_pending()
gpio: pca953x: remove redundant variable and check in IRQ handler
lib/bitmap: introduce bitmap_replace() helper
lib/test_bitmap: fix comment about this file
lib/test_bitmap: move exp1 and exp2 upper for others to use
...
For jited bpf program, if the subprogram count is 1, i.e.,
there is no callees in the program, prog->aux->func will be NULL
and prog->bpf_func points to image address of the program.
If there is more than one subprogram, prog->aux->func is populated,
and subprogram 0 can be accessed through either prog->bpf_func or
prog->aux->func[0]. Other subprograms should be accessed through
prog->aux->func[subprog_id].
This patch fixed a bug in check_attach_btf_id(), where
prog->aux->func[subprog_id] is used to access any subprogram which
caused a segfault like below:
[79162.619208] BUG: kernel NULL pointer dereference, address:
0000000000000000
......
[79162.634255] Call Trace:
[79162.634974] ? _cond_resched+0x15/0x30
[79162.635686] ? kmem_cache_alloc_trace+0x162/0x220
[79162.636398] ? selinux_bpf_prog_alloc+0x1f/0x60
[79162.637111] bpf_prog_load+0x3de/0x690
[79162.637809] __do_sys_bpf+0x105/0x1740
[79162.638488] do_syscall_64+0x5b/0x180
[79162.639147] entry_SYSCALL_64_after_hwframe+0x44/0xa9
......
Fixes: 5b92a28aae ("bpf: Support attaching tracing BPF program to other BPF programs")
Reported-by: Eelco Chaudron <echaudro@redhat.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191205010606.177774-1-yhs@fb.com
Patch series " kcov: collect coverage from usb and vhost", v3.
This patchset extends kcov to allow collecting coverage from backgound
kernel threads. This extension requires custom annotations for each of
the places where coverage collection is desired. This patchset
implements this for hub events in the USB subsystem and for vhost
workers. See the first patch description for details about the kcov
extension. The other two patches apply this kcov extension to USB and
vhost.
Examples of other subsystems that might potentially benefit from this
when custom annotations are added (the list is based on
process_one_work() callers for bugs recently reported by syzbot):
1. fs: writeback wb_workfn() worker,
2. net: addrconf_dad_work()/addrconf_verify_work() workers,
3. net: neigh_periodic_work() worker,
4. net/p9: p9_write_work()/p9_read_work() workers,
5. block: blk_mq_run_work_fn() worker.
These patches have been used to enable coverage-guided USB fuzzing with
syzkaller for the last few years, see the details here:
https://github.com/google/syzkaller/blob/master/docs/linux/external_fuzzing_usb.md
This patchset has been pushed to the public Linux kernel Gerrit
instance:
https://linux-review.googlesource.com/c/linux/kernel/git/torvalds/linux/+/1524
This patch (of 3):
Add background thread coverage collection ability to kcov.
With KCOV_ENABLE coverage is collected only for syscalls that are issued
from the current process. With KCOV_REMOTE_ENABLE it's possible to
collect coverage for arbitrary parts of the kernel code, provided that
those parts are annotated with kcov_remote_start()/kcov_remote_stop().
This allows to collect coverage from two types of kernel background
threads: the global ones, that are spawned during kernel boot in a
limited number of instances (e.g. one USB hub_event() worker thread is
spawned per USB HCD); and the local ones, that are spawned when a user
interacts with some kernel interface (e.g. vhost workers).
To enable collecting coverage from a global background thread, a unique
global handle must be assigned and passed to the corresponding
kcov_remote_start() call. Then a userspace process can pass a list of
such handles to the KCOV_REMOTE_ENABLE ioctl in the handles array field
of the kcov_remote_arg struct. This will attach the used kcov device to
the code sections, that are referenced by those handles.
Since there might be many local background threads spawned from
different userspace processes, we can't use a single global handle per
annotation. Instead, the userspace process passes a non-zero handle
through the common_handle field of the kcov_remote_arg struct. This
common handle gets saved to the kcov_handle field in the current
task_struct and needs to be passed to the newly spawned threads via
custom annotations. Those threads should in turn be annotated with
kcov_remote_start()/kcov_remote_stop().
Internally kcov stores handles as u64 integers. The top byte of a
handle is used to denote the id of a subsystem that this handle belongs
to, and the lower 4 bytes are used to denote the id of a thread instance
within that subsystem. A reserved value 0 is used as a subsystem id for
common handles as they don't belong to a particular subsystem. The
bytes 4-7 are currently reserved and must be zero. In the future the
number of bytes used for the subsystem or handle ids might be increased.
When a particular userspace process collects coverage by via a common
handle, kcov will collect coverage for each code section that is
annotated to use the common handle obtained as kcov_handle from the
current task_struct. However non common handles allow to collect
coverage selectively from different subsystems.
Link: http://lkml.kernel.org/r/e90e315426a384207edbec1d6aa89e43008e4caf.1572366574.git.andreyknvl@google.com
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: "Michael S. Tsirkin" <mst@redhat.com>
Cc: Jason Wang <jasowang@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: David Windsor <dwindsor@gmail.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Anders Roxell <anders.roxell@linaro.org>
Cc: Alexander Potapenko <glider@google.com>
Cc: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Initialization is not guaranteed to zero padding bytes so use an
explicit memset instead to avoid leaking any kernel content in any
possible padding bytes.
Link: http://lkml.kernel.org/r/dfa331c00881d61c8ee51577a082d8bebd61805c.camel@perches.com
Signed-off-by: Joe Perches <joe@perches.com>
Cc: Dan Carpenter <error27@gmail.com>
Cc: Julia Lawall <julia.lawall@lip6.fr>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When building with clang + -Wtautological-pointer-compare, these
instances pop up:
kernel/profile.c:339:6: warning: comparison of array 'prof_cpu_mask' not equal to a null pointer is always true [-Wtautological-pointer-compare]
if (prof_cpu_mask != NULL)
^~~~~~~~~~~~~ ~~~~
kernel/profile.c:376:6: warning: comparison of array 'prof_cpu_mask' not equal to a null pointer is always true [-Wtautological-pointer-compare]
if (prof_cpu_mask != NULL)
^~~~~~~~~~~~~ ~~~~
kernel/profile.c:406:26: warning: comparison of array 'prof_cpu_mask' not equal to a null pointer is always true [-Wtautological-pointer-compare]
if (!user_mode(regs) && prof_cpu_mask != NULL &&
^~~~~~~~~~~~~ ~~~~
3 warnings generated.
This can be addressed with the cpumask_available helper, introduced in
commit f7e30f01a9 ("cpumask: Add helper cpumask_available()") to fix
warnings like this while keeping the code the same.
Link: https://github.com/ClangBuiltLinux/linux/issues/747
Link: http://lkml.kernel.org/r/20191022191957.9554-1-natechancellor@gmail.com
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
blocking_notifier_chain_cond_register() does not consider system_booting
state, which is the only difference between this function and
blocking_notifier_cain_register(). This can be a bug and is a piece of
duplicate code.
Delete blocking_notifier_chain_cond_register()
Link: http://lkml.kernel.org/r/1568861888-34045-4-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The only difference between notifier_chain_cond_register() and
notifier_chain_register() is the lack of warning hints for duplicate
registrations. Use notifier_chain_register() instead of
notifier_chain_cond_register() to avoid duplicate code
Link: http://lkml.kernel.org/r/1568861888-34045-3-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Registering the same notifier to a hook repeatedly can cause the hook
list to form a ring or lose other members of the list.
case1: An infinite loop in notifier_chain_register() can cause soft lockup
atomic_notifier_chain_register(&test_notifier_list, &test1);
atomic_notifier_chain_register(&test_notifier_list, &test1);
atomic_notifier_chain_register(&test_notifier_list, &test2);
case2: An infinite loop in notifier_chain_register() can cause soft lockup
atomic_notifier_chain_register(&test_notifier_list, &test1);
atomic_notifier_chain_register(&test_notifier_list, &test1);
atomic_notifier_call_chain(&test_notifier_list, 0, NULL);
case3: lose other hook test2
atomic_notifier_chain_register(&test_notifier_list, &test1);
atomic_notifier_chain_register(&test_notifier_list, &test2);
atomic_notifier_chain_register(&test_notifier_list, &test1);
case4: Unregister returns 0, but the hook is still in the linked list,
and it is not really registered. If you call
notifier_call_chain after ko is unloaded, it will trigger oops.
If the system is configured with softlockup_panic and the same hook is
repeatedly registered on the panic_notifier_list, it will cause a loop
panic.
Add a check in notifier_chain_register(), intercepting duplicate
registrations to avoid infinite loops
Link: http://lkml.kernel.org/r/1568861888-34045-2-git-send-email-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Reviewed-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Anna Schumaker <anna.schumaker@netapp.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Nadia Derbey <Nadia.Derbey@bull.net>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Sam Protsenko <semen.protsenko@linaro.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Trond Myklebust <trond.myklebust@hammerspace.com>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Xiaoming Ni <nixiaoming@huawei.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fixes:
- Missing __print_hex_dump undef for processing new function in trace events
- Stop WARN_ON messages when lockdown disables tracing on boot up
Enhancement:
- Debug option to inject trace events from userspace (for rasdaemon)
The enhancement has its own config option and is non invasive. It's been
discussed for sever months and should have been added to my original
push, but I never pulled it into my queue.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXehlhRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlGgAQCszcDuNyVllj0VwWi4i+0FAQcI12Ad
W0NGZm0wObGExwD8CDR/CdHq9ulizFQjJfopG6b5Uc3Z4NNJ+QGnMxzBuwo=
=k31z
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull more tracing updates from Steven Rostedt:
"Two fixes and one patch that was missed:
Fixes:
- Missing __print_hex_dump undef for processing new function in trace
events
- Stop WARN_ON messages when lockdown disables tracing on boot up
Enhancement:
- Debug option to inject trace events from userspace (for rasdaemon)"
The enhancement has its own config option and is non invasive. It's been
discussed for sever months and should have been added to my original
push, but I never pulled it into my queue.
* tag 'trace-v5.5-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Do not create directories if lockdown is in affect
tracing: Introduce trace event injection
tracing: Fix __print_hex_dump scope
- Avoid a race condition in the ACPI EC driver that may cause
systems to be unable to leave suspend-to-idle (Rafael Wysocki).
- Drop the "disabled" field, which is redundant, from struct
cpuidle_state (Rafael Wysocki).
- Reintroduce device PM QoS frequency constraints (temporarily
introduced and than dropped during the 5.4 cycle) in preparation
for adding QoS support to devfreq (Leonard Crestez).
- Clean up indentation (in multiple places) and the cpuidle drivers
help text in Kconfig (Krzysztof Kozlowski, Randy Dunlap).
-----BEGIN PGP SIGNATURE-----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=KAyd
-----END PGP SIGNATURE-----
Merge tag 'pm-5.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull additional power management updates from Rafael Wysocki:
"These fix an ACPI EC driver bug exposed by the recent rework of the
suspend-to-idle code flow, reintroduce frequency constraints into
device PM QoS (in preparation for adding QoS support to devfreq), drop
a redundant field from struct cpuidle_state and clean up Kconfig in
some places.
Specifics:
- Avoid a race condition in the ACPI EC driver that may cause systems
to be unable to leave suspend-to-idle (Rafael Wysocki)
- Drop the "disabled" field, which is redundant, from struct
cpuidle_state (Rafael Wysocki)
- Reintroduce device PM QoS frequency constraints (temporarily
introduced and than dropped during the 5.4 cycle) in preparation
for adding QoS support to devfreq (Leonard Crestez)
- Clean up indentation (in multiple places) and the cpuidle drivers
help text in Kconfig (Krzysztof Kozlowski, Randy Dunlap)"
* tag 'pm-5.5-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: PM: s2idle: Rework ACPI events synchronization
ACPI: EC: Rework flushing of pending work
PM / devfreq: Add missing locking while setting suspend_freq
PM / QoS: Restore DEV_PM_QOS_MIN/MAX_FREQUENCY
PM / QoS: Reorder pm_qos/freq_qos/dev_pm_qos structs
PM / QoS: Initial kunit test
PM / QoS: Redefine FREQ_QOS_MAX_DEFAULT_VALUE to S32_MAX
power: avs: Fix Kconfig indentation
cpufreq: Fix Kconfig indentation
cpuidle: minor Kconfig help text fixes
cpuidle: Drop disabled field from struct cpuidle_state
cpuidle: Fix Kconfig indentation
When assiging and testing taskstats in taskstats_exit() there's a race
when setting up and reading sig->stats when a thread-group with more
than one thread exits:
write to 0xffff8881157bbe10 of 8 bytes by task 7951 on cpu 0:
taskstats_tgid_alloc kernel/taskstats.c:567 [inline]
taskstats_exit+0x6b7/0x717 kernel/taskstats.c:596
do_exit+0x2c2/0x18e0 kernel/exit.c:864
do_group_exit+0xb4/0x1c0 kernel/exit.c:983
get_signal+0x2a2/0x1320 kernel/signal.c:2734
do_signal+0x3b/0xc00 arch/x86/kernel/signal.c:815
exit_to_usermode_loop+0x250/0x2c0 arch/x86/entry/common.c:159
prepare_exit_to_usermode arch/x86/entry/common.c:194 [inline]
syscall_return_slowpath arch/x86/entry/common.c:274 [inline]
do_syscall_64+0x2d7/0x2f0 arch/x86/entry/common.c:299
entry_SYSCALL_64_after_hwframe+0x44/0xa9
read to 0xffff8881157bbe10 of 8 bytes by task 7949 on cpu 1:
taskstats_tgid_alloc kernel/taskstats.c:559 [inline]
taskstats_exit+0xb2/0x717 kernel/taskstats.c:596
do_exit+0x2c2/0x18e0 kernel/exit.c:864
do_group_exit+0xb4/0x1c0 kernel/exit.c:983
__do_sys_exit_group kernel/exit.c:994 [inline]
__se_sys_exit_group kernel/exit.c:992 [inline]
__x64_sys_exit_group+0x2e/0x30 kernel/exit.c:992
do_syscall_64+0xcf/0x2f0 arch/x86/entry/common.c:296
entry_SYSCALL_64_after_hwframe+0x44/0xa9
Fix this by using smp_load_acquire() and smp_store_release().
Reported-by: syzbot+c5d03165a1bd1dead0c1@syzkaller.appspotmail.com
Fixes: 34ec12349c ("taskstats: cleanup ->signal->stats allocation")
Cc: stable@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Marco Elver <elver@google.com>
Reviewed-by: Will Deacon <will@kernel.org>
Reviewed-by: Andrea Parri <parri.andrea@gmail.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Link: https://lore.kernel.org/r/20191009114809.8643-1-christian.brauner@ubuntu.com
If lockdown is disabling tracing on boot up, it prevents the tracing files
from even bering created. But when that happens, there's several places that
will give a warning that the files were not created as that is usually a
sign of a bug.
Add in strategic locations where a check is made to see if tracing is
disabled by lockdown, and if it is, do not go further, and fail silently
(but print that tracing is disabled by lockdown, without doing a WARN_ON()).
Cc: Matthew Garrett <mjg59@google.com>
Fixes: 17911ff38a ("tracing: Add locked_down checks to the open calls of files created for tracefs")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull timer updates from Ingo Molnar:
"The main changes in the timer code in this cycle were:
- Clockevent updates:
- timer-of framework cleanups. (Geert Uytterhoeven)
- Use timer-of for the renesas-ostm and the device name to prevent
name collision in case of multiple timers. (Geert Uytterhoeven)
- Check if there is an error after calling of_clk_get in asm9260
(Chuhong Yuan)
- ABI fix: Zero out high order bits of nanoseconds on compat
syscalls. This got broken a year ago, with apparently no side
effects so far.
Since the kernel would use random data otherwise I don't think we'd
have other options but to fix the bug, even if there was a side
effect to applications (Dmitry Safonov)
- Optimize ns_to_timespec64() on 32-bit systems: move away from
div_s64_rem() which can be slow, to div_u64_rem() which is faster
(Arnd Bergmann)
- Annotate KCSAN-reported false positive data races in
hrtimer_is_queued() users by moving timer->state handling over to
the READ_ONCE()/WRITE_ONCE() APIs. This documents these accesses
(Eric Dumazet)
- Misc cleanups and small fixes"
[ I undid the "ABI fix" and updated the comments instead. The reason
there were apparently no side effects is that the fix was a no-op.
The updated comment is to say _why_ it was a no-op. - Linus ]
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Zero the upper 32-bits in __kernel_timespec on 32-bit
time: Rename tsk->real_start_time to ->start_boottime
hrtimer: Remove the comment about not used HRTIMER_SOFTIRQ
time: Fix spelling mistake in comment
time: Optimize ns_to_timespec64()
hrtimer: Annotate lockless access to timer->state
clocksource/drivers/asm9260: Add a check for of_clk_get
clocksource/drivers/renesas-ostm: Use unique device name instead of ostm
clocksource/drivers/renesas-ostm: Convert to timer_of
clocksource/drivers/timer-of: Use unique device name instead of timer
clocksource/drivers/timer-of: Convert last full_name to %pOF
Pull irq updates from Ingo Molnar:
"Most of the IRQ subsystem changes in this cycle were irq-chip driver
updates:
- Qualcomm PDC wakeup interrupt support
- Layerscape external IRQ support
- Broadcom bcm7038 PM and wakeup support
- Ingenic driver cleanup and modernization
- GICv3 ITS preparation for GICv4.1 updates
- GICv4 fixes
There's also the series from Frederic Weisbecker that fixes memory
ordering bugs for the irq-work logic, whose primary fix is to turn
work->irq_work.flags into an atomic variable and then convert the
complex (and buggy) atomic_cmpxchg() loop in irq_work_claim() into a
much simpler atomic_fetch_or() call.
There are also various smaller cleanups"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (44 commits)
pinctrl/sdm845: Add PDC wakeup interrupt map for GPIOs
pinctrl/msm: Setup GPIO chip in hierarchy
irqchip/qcom-pdc: Add irqchip set/get state calls
irqchip/qcom-pdc: Add irqdomain for wakeup capable GPIOs
irqchip/qcom-pdc: Do not toggle IRQ_ENABLE during mask/unmask
irqchip/qcom-pdc: Update max PDC interrupts
of/irq: Document properties for wakeup interrupt parent
genirq: Introduce irq_chip_get/set_parent_state calls
irqdomain: Add bus token DOMAIN_BUS_WAKEUP
genirq: Fix function documentation of __irq_alloc_descs()
irq_work: Fix IRQ_WORK_BUSY bit clearing
irqchip/ti-sci-inta: Use ERR_CAST inlined function instead of ERR_PTR(PTR_ERR(...))
irq_work: Slightly simplify IRQ_WORK_PENDING clearing
irq_work: Fix irq_work_claim() memory ordering
irq_work: Convert flags to atomic_t
irqchip: Ingenic: Add process for more than one irq at the same time.
irqchip: ingenic: Alloc generic chips from IRQ domain
irqchip: ingenic: Get virq number from IRQ domain
irqchip: ingenic: Error out if IRQ domain creation failed
irqchip: ingenic: Drop redundant irq_suspend / irq_resume functions
...
- remove unneeded asm headers from hexagon, ia64
- add 'dir-pkg' target, which works like 'tar-pkg' but skips archiving
- add 'helpnewconfig' target, which shows help for new CONFIG options
- support 'make nsdeps' for external modules
- make rebuilds faster by deleting $(wildcard $^) checks
- remove compile tests for kernel-space headers
- refactor modpost to simplify modversion handling
- make single target builds faster
- optimize and clean up scripts/kallsyms.c
- refactor various Makefiles and scripts
-----BEGIN PGP SIGNATURE-----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=zUaB
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- remove unneeded asm headers from hexagon, ia64
- add 'dir-pkg' target, which works like 'tar-pkg' but skips archiving
- add 'helpnewconfig' target, which shows help for new CONFIG options
- support 'make nsdeps' for external modules
- make rebuilds faster by deleting $(wildcard $^) checks
- remove compile tests for kernel-space headers
- refactor modpost to simplify modversion handling
- make single target builds faster
- optimize and clean up scripts/kallsyms.c
- refactor various Makefiles and scripts
* tag 'kbuild-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (59 commits)
MAINTAINERS: update Kbuild/Kconfig maintainer's email address
scripts/kallsyms: remove redundant initializers
scripts/kallsyms: put check_symbol_range() calls close together
scripts/kallsyms: make check_symbol_range() void function
scripts/kallsyms: move ignored symbol types to is_ignored_symbol()
scripts/kallsyms: move more patterns to the ignored_prefixes array
scripts/kallsyms: skip ignored symbols very early
scripts/kallsyms: add const qualifiers where possible
scripts/kallsyms: make find_token() return (unsigned char *)
scripts/kallsyms: replace prefix_underscores_count() with strspn()
scripts/kallsyms: add sym_name() to mitigate cast ugliness
scripts/kallsyms: remove unneeded length check for prefix matching
scripts/kallsyms: remove redundant is_arm_mapping_symbol()
scripts/kallsyms: set relative_base more effectively
scripts/kallsyms: shrink table before sorting it
scripts/kallsyms: fix definitely-lost memory leak
scripts/kallsyms: remove unneeded #ifndef ARRAY_SIZE
kbuild: make single target builds even faster
modpost: respect the previous export when 'exported twice' is warned
modpost: do not set ->preloaded for symbols from Module.symvers
...
Daniel Borkmann says:
====================
pull-request: bpf 2019-12-02
The following pull-request contains BPF updates for your *net* tree.
We've added 10 non-merge commits during the last 6 day(s) which contain
a total of 10 files changed, 60 insertions(+), 51 deletions(-).
The main changes are:
1) Fix vmlinux BTF generation for binutils pre v2.25, from Stanislav Fomichev.
2) Fix libbpf global variable relocation to take symbol's st_value offset
into account, from Andrii Nakryiko.
3) Fix libbpf build on powerpc where check_abi target fails due to different
readelf output format, from Aurelien Jarno.
4) Don't set BPF insns RO for the case when they are JITed in order to avoid
fragmenting the direct map, from Daniel Borkmann.
5) Fix static checker warning in btf_distill_func_proto() as well as a build
error due to empty enum when BPF is compiled out, from Alexei Starovoitov.
6) Fix up generation of bpf_helper_defs.h for perf, from Arnaldo Carvalho de Melo.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
We have been trying to use rasdaemon to monitor hardware errors like
correctable memory errors. rasdaemon uses trace events to monitor
various hardware errors. In order to test it, we have to inject some
hardware errors, unfortunately not all of them provide error
injections. MCE does provide a way to inject MCE errors, but errors
like PCI error and devlink error don't, it is not easy to add error
injection to each of them. Instead, it is relatively easier to just
allow users to inject trace events in a generic way so that all trace
events can be injected.
This patch introduces trace event injection, where a new 'inject' is
added to each tracepoint directory. Users could write into this file
with key=value pairs to specify the value of each fields of the trace
event, all unspecified fields are set to zero values by default.
For example, for the net/net_dev_queue tracepoint, we can inject:
INJECT=/sys/kernel/debug/tracing/events/net/net_dev_queue/inject
echo "" > $INJECT
echo "name='test'" > $INJECT
echo "name='test' len=1024" > $INJECT
cat /sys/kernel/debug/tracing/trace
...
<...>-614 [000] .... 36.571483: net_dev_queue: dev= skbaddr=00000000fbf338c2 len=0
<...>-614 [001] .... 136.588252: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=0
<...>-614 [001] .N.. 208.431878: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=1024
Triggers could be triggered as usual too:
echo "stacktrace if len == 1025" > /sys/kernel/debug/tracing/events/net/net_dev_queue/trigger
echo "len=1025" > $INJECT
cat /sys/kernel/debug/tracing/trace
...
bash-614 [000] .... 36.571483: net_dev_queue: dev= skbaddr=00000000fbf338c2 len=0
bash-614 [001] .... 136.588252: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=0
bash-614 [001] .N.. 208.431878: net_dev_queue: dev=test skbaddr=00000000fbf338c2 len=1024
bash-614 [001] .N.1 284.236349: <stack trace>
=> event_inject_write
=> vfs_write
=> ksys_write
=> do_syscall_64
=> entry_SYSCALL_64_after_hwframe
The only thing that can't be injected is string pointers as they
require constant string pointers, this can't be done at run time.
Link: http://lkml.kernel.org/r/20191130045218.18979-1-xiyou.wangcong@gmail.com
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Merge updates from Andrew Morton:
"Incoming:
- a small number of updates to scripts/, ocfs2 and fs/buffer.c
- most of MM
I still have quite a lot of material (mostly not MM) staged after
linux-next due to -next dependencies. I'll send those across next week
as the preprequisites get merged up"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (135 commits)
mm/page_io.c: annotate refault stalls from swap_readpage
mm/Kconfig: fix trivial help text punctuation
mm/Kconfig: fix indentation
mm/memory_hotplug.c: remove __online_page_set_limits()
mm: fix typos in comments when calling __SetPageUptodate()
mm: fix struct member name in function comments
mm/shmem.c: cast the type of unmap_start to u64
mm: shmem: use proper gfp flags for shmem_writepage()
mm/shmem.c: make array 'values' static const, makes object smaller
userfaultfd: require CAP_SYS_PTRACE for UFFD_FEATURE_EVENT_FORK
fs/userfaultfd.c: wp: clear VM_UFFD_MISSING or VM_UFFD_WP during userfaultfd_register()
userfaultfd: wrap the common dst_vma check into an inlined function
userfaultfd: remove unnecessary WARN_ON() in __mcopy_atomic_hugetlb()
userfaultfd: use vma_pagesize for all huge page size calculation
mm/madvise.c: use PAGE_ALIGN[ED] for range checking
mm/madvise.c: replace with page_size() in madvise_inject_error()
mm/mmap.c: make vma_merge() comment more easy to understand
mm/hwpoison-inject: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops
autonuma: reduce cache footprint when scanning page tables
autonuma: fix watermark checking in migrate_balanced_pgdat()
...
This is a series of cleanups for the y2038 work, mostly intended
for namespace cleaning: the kernel defines the traditional
time_t, timeval and timespec types that often lead to y2038-unsafe
code. Even though the unsafe usage is mostly gone from the kernel,
having the types and associated functions around means that we
can still grow new users, and that we may be missing conversions
to safe types that actually matter.
There are still a number of driver specific patches needed to
get the last users of these types removed, those have been
submitted to the respective maintainers.
Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2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=Bdbv
-----END PGP SIGNATURE-----
Merge tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground
Pull y2038 cleanups from Arnd Bergmann:
"y2038 syscall implementation cleanups
This is a series of cleanups for the y2038 work, mostly intended for
namespace cleaning: the kernel defines the traditional time_t, timeval
and timespec types that often lead to y2038-unsafe code. Even though
the unsafe usage is mostly gone from the kernel, having the types and
associated functions around means that we can still grow new users,
and that we may be missing conversions to safe types that actually
matter.
There are still a number of driver specific patches needed to get the
last users of these types removed, those have been submitted to the
respective maintainers"
Link: https://lore.kernel.org/lkml/20191108210236.1296047-1-arnd@arndb.de/
* tag 'y2038-cleanups-5.5' of git://git.kernel.org:/pub/scm/linux/kernel/git/arnd/playground: (26 commits)
y2038: alarm: fix half-second cut-off
y2038: ipc: fix x32 ABI breakage
y2038: fix typo in powerpc vdso "LOPART"
y2038: allow disabling time32 system calls
y2038: itimer: change implementation to timespec64
y2038: move itimer reset into itimer.c
y2038: use compat_{get,set}_itimer on alpha
y2038: itimer: compat handling to itimer.c
y2038: time: avoid timespec usage in settimeofday()
y2038: timerfd: Use timespec64 internally
y2038: elfcore: Use __kernel_old_timeval for process times
y2038: make ns_to_compat_timeval use __kernel_old_timeval
y2038: socket: use __kernel_old_timespec instead of timespec
y2038: socket: remove timespec reference in timestamping
y2038: syscalls: change remaining timeval to __kernel_old_timeval
y2038: rusage: use __kernel_old_timeval
y2038: uapi: change __kernel_time_t to __kernel_old_time_t
y2038: stat: avoid 'time_t' in 'struct stat'
y2038: ipc: remove __kernel_time_t reference from headers
y2038: vdso: powerpc: avoid timespec references
...
Pull sysctl system call removal from Eric Biederman:
"As far as I can tell we have reached the point where no one enables
the sysctl system call anymore. It still is enabled in a few
defconfigs but they are mostly the rarely used one and in asking
people about that it was more cut & paste enabled than anything else.
This is single commit that just deletes code. Leaving just enough code
so that the deprecated sysctl warning continues to be printed. If my
analysis turns out to be wrong and someone actually cares it will be
easy to revert this commit and have the system call again.
There was one new xtensa defconfig in linux-next that enabled the
system call this cycle and when asked about it the maintainer of the
code replied that it was not enabled on purpose. As of today's
linux-next tree that defconfig no longer enables the system call.
What we saw in the review discussion was that if we go a step farther
than my patch and mess with uapi headers there are pieces of code that
won't compile, but nothing minds the system call actually disappearing
from the kernel"
Link: https://lore.kernel.org/lkml/201910011140.EA0181F13@keescook/
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
sysctl: Remove the sysctl system call
Currently, the drop_caches proc file and sysctl read back the last value
written, suggesting this is somehow a stateful setting instead of a
one-time command. Make it write-only, like e.g. compact_memory.
While mitigating a VM problem at scale in our fleet, there was confusion
about whether writing to this file will permanently switch the kernel into
a non-caching mode. This influences the decision making in a tense
situation, where tens of people are trying to fix tens of thousands of
affected machines: Do we need a rollback strategy? What are the
performance implications of operating in a non-caching state for several
days? It also caused confusion when the kernel team said we may need to
write the file several times to make sure it's effective ("But it already
reads back 3?").
Link: http://lkml.kernel.org/r/20191031221602.9375-1-hannes@cmpxchg.org
Signed-off-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Chris Down <chris@chrisdown.name>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Supporting VMAP_STACK with KASAN_VMALLOC is straightforward:
- clear the shadow region of vmapped stacks when swapping them in
- tweak Kconfig to allow VMAP_STACK to be turned on with KASAN
Link: http://lkml.kernel.org/r/20191031093909.9228-4-dja@axtens.net
Signed-off-by: Daniel Axtens <dja@axtens.net>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
get_unmapped_area() returns an address or -errno on failure. Historically
we have checked for the failure by offset_in_page() which is correct but
quite hard to read. Newer code started using IS_ERR_VALUE which is much
easier to read. Convert remaining users of offset_in_page as well.
[mhocko@suse.com: rewrite changelog]
[mhocko@kernel.org: fix mremap.c and uprobes.c sites also]
Link: http://lkml.kernel.org/r/20191012102512.28051-1-pugaowei@gmail.com
Signed-off-by: Gaowei Pu <pugaowei@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: "Jérôme Glisse" <jglisse@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Qian Cai <cai@lca.pw>
Cc: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----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=fc7R
-----END PGP SIGNATURE-----
Merge tag 'audit-pr-20191126' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"Audit is back for v5.5, albeit with only two patches:
- Allow for the auditing of suspicious O_CREAT usage via the new
AUDIT_ANOM_CREAT record.
- Remove a redundant if-conditional check found during code analysis.
It's a minor change, but when the pull request is only two patches
long, you need filler in the pull request email"
[ Heh on the pull request filler. I wish more people tried to write
better pull request messages, even if maybe it's not worth it for the
trivial cases ;^) - Linus ]
* tag 'audit-pr-20191126' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: remove redundant condition check in kauditd_thread()
audit: Report suspicious O_CREAT usage
The major change here is the work from Douglas Anderson that
reworks the way kdb stack traces are handled on SMP systems.
The effect is to allow all CPUs to issue their stack trace which
reduced the need for architecture specific code to support stack
tracing.
Also included are general of clean ups from Doug and myself:
* Remove some unused variables or arguments.
* Tidy up the kdb escape handling code and fix a couple of odd
corner cases.
- Better ignore escape characters that do not form part of an
escape sequence. This mostly benefits vi users since they are most
likely to press escape as a nervous habit but it won't harm anyone
else.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
-----BEGIN PGP SIGNATURE-----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=CZKd
-----END PGP SIGNATURE-----
Merge tag 'kgdb-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson:
"The major change here is the work from Douglas Anderson that reworks
the way kdb stack traces are handled on SMP systems. The effect is to
allow all CPUs to issue their stack trace which reduced the need for
architecture specific code to support stack tracing.
Also included are general of clean ups from Doug and myself:
- Remove some unused variables or arguments.
- Tidy up the kdb escape handling code and fix a couple of odd corner
cases.
- Better ignore escape characters that do not form part of an escape
sequence. This mostly benefits vi users since they are most likely
to press escape as a nervous habit but it won't harm anyone else"
* tag 'kgdb-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kdb: Tweak escape handling for vi users
kdb: Improve handling of characters from different input sources
kdb: Remove special case logic from kdb_read()
kdb: Simplify code to fetch characters from console
kdb: Tidy up code to handle escape sequences
kdb: Avoid array subscript warnings on non-SMP builds
kdb: Fix stack crawling on 'running' CPUs that aren't the master
kdb: Fix "btc <cpu>" crash if the CPU didn't round up
kdb: Remove unused "argcount" param from kdb_bt1(); make btaprompt bool
kgdb: Remove unused DCPU_SSTEP definition
Pull parisc updates from Helge Deller:
"Just trivial small updates: An assembler register optimization in the
inlined networking checksum functions, a compiler warning fix and
don't unneccesary print a runtime warning on machines which wouldn't
be affected anyway"
* 'parisc-5.5-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Avoid spurious inequivalent alias kernel error messages
kexec: Fix pointer-to-int-cast warnings
parisc: Do not hardcode registers in checksum functions
-----BEGIN PGP SIGNATURE-----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=FKC7
-----END PGP SIGNATURE-----
Merge tag 'notifications-pipe-prep-20191115' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull pipe rework from David Howells:
"This is my set of preparatory patches for building a general
notification queue on top of pipes. It makes a number of significant
changes:
- It removes the nr_exclusive argument from __wake_up_sync_key() as
this is always 1. This prepares for the next step:
- Adds wake_up_interruptible_sync_poll_locked() so that poll can be
woken up from a function that's holding the poll waitqueue
spinlock.
- Change the pipe buffer ring to be managed in terms of unbounded
head and tail indices rather than bounded index and length. This
means that reading the pipe only needs to modify one index, not
two.
- A selection of helper functions are provided to query the state of
the pipe buffer, plus a couple to apply updates to the pipe
indices.
- The pipe ring is allowed to have kernel-reserved slots. This allows
many notification messages to be spliced in by the kernel without
allowing userspace to pin too many pages if it writes to the same
pipe.
- Advance the head and tail indices inside the pipe waitqueue lock
and use wake_up_interruptible_sync_poll_locked() to poke poll
without having to take the lock twice.
- Rearrange pipe_write() to preallocate the buffer it is going to
write into and then drop the spinlock. This allows kernel
notifications to then be added the ring whilst it is filling the
buffer it allocated. The read side is stalled because the pipe
mutex is still held.
- Don't wake up readers on a pipe if there was already data in it
when we added more.
- Don't wake up writers on a pipe if the ring wasn't full before we
removed a buffer"
* tag 'notifications-pipe-prep-20191115' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
pipe: Remove sync on wake_ups
pipe: Increase the writer-wakeup threshold to reduce context-switch count
pipe: Check for ring full inside of the spinlock in pipe_write()
pipe: Remove redundant wakeup from pipe_write()
pipe: Rearrange sequence in pipe_write() to preallocate slot
pipe: Conditionalise wakeup in pipe_read()
pipe: Advance tail pointer inside of wait spinlock in pipe_read()
pipe: Allow pipes to have kernel-reserved slots
pipe: Use head and tail pointers for the ring, not cursor and length
Add wake_up_interruptible_sync_poll_locked()
Remove the nr_exclusive argument from __wake_up_sync_key()
pipe: Reduce #inclusion of pipe_fs_i.h
This is another round of bug fixing and cleanup. This time the focus is on
the driver pattern to use mmu notifiers to monitor a VA range. This code
is lifted out of many drivers and hmm_mirror directly into the
mmu_notifier core and written using the best ideas from all the driver
implementations.
This removes many bugs from the drivers and has a very pleasing
diffstat. More drivers can still be converted, but that is for another
cycle.
- A shared branch with RDMA reworking the RDMA ODP implementation
- New mmu_interval_notifier API. This is focused on the use case of
monitoring a VA and simplifies the process for drivers
- A common seq-count locking scheme built into the mmu_interval_notifier
API usable by drivers that call get_user_pages() or hmm_range_fault()
with the VA range
- Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen GntDev
drivers to the new API. This deletes a lot of wonky driver code.
- Two improvements for hmm_range_fault(), from testing done by Ralph
-----BEGIN PGP SIGNATURE-----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=Hj8a
-----END PGP SIGNATURE-----
Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull hmm updates from Jason Gunthorpe:
"This is another round of bug fixing and cleanup. This time the focus
is on the driver pattern to use mmu notifiers to monitor a VA range.
This code is lifted out of many drivers and hmm_mirror directly into
the mmu_notifier core and written using the best ideas from all the
driver implementations.
This removes many bugs from the drivers and has a very pleasing
diffstat. More drivers can still be converted, but that is for another
cycle.
- A shared branch with RDMA reworking the RDMA ODP implementation
- New mmu_interval_notifier API. This is focused on the use case of
monitoring a VA and simplifies the process for drivers
- A common seq-count locking scheme built into the
mmu_interval_notifier API usable by drivers that call
get_user_pages() or hmm_range_fault() with the VA range
- Conversion of mlx5 ODP, hfi1, radeon, nouveau, AMD GPU, and Xen
GntDev drivers to the new API. This deletes a lot of wonky driver
code.
- Two improvements for hmm_range_fault(), from testing done by Ralph"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma:
mm/hmm: remove hmm_range_dma_map and hmm_range_dma_unmap
mm/hmm: make full use of walk_page_range()
xen/gntdev: use mmu_interval_notifier_insert
mm/hmm: remove hmm_mirror and related
drm/amdgpu: Use mmu_interval_notifier instead of hmm_mirror
drm/amdgpu: Use mmu_interval_insert instead of hmm_mirror
drm/amdgpu: Call find_vma under mmap_sem
nouveau: use mmu_interval_notifier instead of hmm_mirror
nouveau: use mmu_notifier directly for invalidate_range_start
drm/radeon: use mmu_interval_notifier_insert
RDMA/hfi1: Use mmu_interval_notifier_insert for user_exp_rcv
RDMA/odp: Use mmu_interval_notifier_insert()
mm/hmm: define the pre-processor related parts of hmm.h even if disabled
mm/hmm: allow hmm_range to be used with a mmu_interval_notifier or hmm_mirror
mm/mmu_notifier: add an interval tree notifier
mm/mmu_notifier: define the header pre-processor parts even if disabled
mm/hmm: allow snapshot of the special zero page
Support for adding per-device frequency limits was removed in
commit 2aac8bdf7a ("PM: QoS: Drop frequency QoS types from device PM QoS")
after cpufreq switched to use a new "freq_constraints" construct.
Restore support for per-device freq limits but base this upon
freq_constraints. This is primarily meant to be used by the devfreq
subsystem.
This removes the "static" marking on freq_qos_apply but does not export
it for modules.
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Reviewed-by: Matthias Kaehlcke <mka@chromium.org>
Tested-by: Matthias Kaehlcke <mka@chromium.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
sched_clock_running is enabled early at bootup stage and never
disabled. So hint that to the compiler by using static_branch_likely()
rather than static_branch_unlikely().
The branch probability mis-annotation was introduced in the original
commit that converted the plain sched_clock_running flag to a static key:
46457ea464 ("sched/clock: Use static key for sched_clock_running")
Steve further notes:
| Looks like the confusion was the moving of the "!":
|
| - if (unlikely(!sched_clock_running))
| + if (!static_branch_unlikely(&sched_clock_running))
|
| Where, it was unlikely that !sched_clock_running would be true, but
| because the "!" was moved outside the "unlikely()" it makes the test
| "likely()". That is, if we added an intermediate step, it would have
| been:
|
| if (!likely(sched_clock_running))
|
| which would have prevented the mistake that this patch fixes.
[ mingo: Edited the changelog. ]
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: mgorman@suse.de
Cc: vincent.guittot@linaro.org
Link: https://lkml.kernel.org/r/1574843848-26825-1-git-send-email-zhenzhong.duan@oracle.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This fixes various data races in spinlock_debug. By testing with KCSAN,
it is observable that the console gets spammed with data races reports,
suggesting these are extremely frequent.
Example data race report:
read to 0xffff8ab24f403c48 of 4 bytes by task 221 on cpu 2:
debug_spin_lock_before kernel/locking/spinlock_debug.c:85 [inline]
do_raw_spin_lock+0x9b/0x210 kernel/locking/spinlock_debug.c:112
__raw_spin_lock include/linux/spinlock_api_smp.h:143 [inline]
_raw_spin_lock+0x39/0x40 kernel/locking/spinlock.c:151
spin_lock include/linux/spinlock.h:338 [inline]
get_partial_node.isra.0.part.0+0x32/0x2f0 mm/slub.c:1873
get_partial_node mm/slub.c:1870 [inline]
<snip>
write to 0xffff8ab24f403c48 of 4 bytes by task 167 on cpu 3:
debug_spin_unlock kernel/locking/spinlock_debug.c:103 [inline]
do_raw_spin_unlock+0xc9/0x1a0 kernel/locking/spinlock_debug.c:138
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:159 [inline]
_raw_spin_unlock_irqrestore+0x2d/0x50 kernel/locking/spinlock.c:191
spin_unlock_irqrestore include/linux/spinlock.h:393 [inline]
free_debug_processing+0x1b3/0x210 mm/slub.c:1214
__slab_free+0x292/0x400 mm/slub.c:2864
<snip>
As a side-effect, with KCSAN, this eventually locks up the console, most
likely due to deadlock, e.g. .. -> printk lock -> spinlock_debug ->
KCSAN detects data race -> kcsan_print_report() -> printk lock ->
deadlock.
This fix will 1) avoid the data races, and 2) allow using lock debugging
together with KCSAN.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Marco Elver <elver@google.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20191120155715.28089-1-elver@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some kconfigs can have BPF enabled without a single valid program type.
In such configurations the build will fail with:
./kernel/bpf/btf.c:3466:1: error: empty enum is invalid
Fix it by adding unused value to the enum.
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/bpf/20191128043508.2346723-1-ast@kernel.org
- improve dma-debug scalability (Eric Dumazet)
- tiny dma-debug cleanup (Dan Carpenter)
- check for vmap memory in dma_map_single (Kees Cook)
- check for dma_addr_t overflows in dma-direct when using
DMA offsets (Nicolas Saenz Julienne)
- switch the x86 sta2x11 SOC to use more generic DMA code
(Nicolas Saenz Julienne)
- fix arm-nommu dma-ranges handling (Vladimir Murzin)
- use __initdata in CMA (Shyam Saini)
- replace the bus dma mask with a limit (Nicolas Saenz Julienne)
- merge the remapping helpers into the main dma-direct flow (me)
- switch xtensa to the generic dma remap handling (me)
- various cleanups around dma_capable (me)
- remove unused dev arguments to various dma-noncoherent helpers (me)
-----BEGIN PGP SIGNATURE-----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=e5wO
-----END PGP SIGNATURE-----
Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux; tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- improve dma-debug scalability (Eric Dumazet)
- tiny dma-debug cleanup (Dan Carpenter)
- check for vmap memory in dma_map_single (Kees Cook)
- check for dma_addr_t overflows in dma-direct when using DMA offsets
(Nicolas Saenz Julienne)
- switch the x86 sta2x11 SOC to use more generic DMA code (Nicolas
Saenz Julienne)
- fix arm-nommu dma-ranges handling (Vladimir Murzin)
- use __initdata in CMA (Shyam Saini)
- replace the bus dma mask with a limit (Nicolas Saenz Julienne)
- merge the remapping helpers into the main dma-direct flow (me)
- switch xtensa to the generic dma remap handling (me)
- various cleanups around dma_capable (me)
- remove unused dev arguments to various dma-noncoherent helpers (me)
* 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux:
* tag 'dma-mapping-5.5' of git://git.infradead.org/users/hch/dma-mapping: (22 commits)
dma-mapping: treat dev->bus_dma_mask as a DMA limit
dma-direct: exclude dma_direct_map_resource from the min_low_pfn check
dma-direct: don't check swiotlb=force in dma_direct_map_resource
dma-debug: clean up put_hash_bucket()
powerpc: remove support for NULL dev in __phys_to_dma / __dma_to_phys
dma-direct: avoid a forward declaration for phys_to_dma
dma-direct: unify the dma_capable definitions
dma-mapping: drop the dev argument to arch_sync_dma_for_*
x86/PCI: sta2x11: use default DMA address translation
dma-direct: check for overflows on 32 bit DMA addresses
dma-debug: increase HASH_SIZE
dma-debug: reorder struct dma_debug_entry fields
xtensa: use the generic uncached segment support
dma-mapping: merge the generic remapping helpers into dma-direct
dma-direct: provide mmap and get_sgtable method overrides
dma-direct: remove the dma_handle argument to __dma_direct_alloc_pages
dma-direct: remove __dma_direct_free_pages
usb: core: Remove redundant vmap checks
kernel: dma-contiguous: mark CMA parameters __initdata/__initconst
dma-debug: add a schedule point in debug_dma_dump_mappings()
...
- PERAMAENT flag to ftrace_ops when attaching a callback to a function
As /proc/sys/kernel/ftrace_enabled when set to zero will disable all
attached callbacks in ftrace, this has a detrimental impact on live
kernel tracing, as it disables all that it patched. If a ftrace_ops
is registered to ftrace with the PERMANENT flag set, it will prevent
ftrace_enabled from being disabled, and if ftrace_enabled is already
disabled, it will prevent a ftrace_ops with PREMANENT flag set from
being registered.
- New register_ftrace_direct(). As eBPF would like to register its own
trampolines to be called by the ftrace nop locations directly,
without going through the ftrace trampoline, this function has been
added. This allows for eBPF trampolines to live along side of
ftrace, perf, kprobe and live patching. It also utilizes the ftrace
enabled_functions file that keeps track of functions that have been
modified in the kernel, to allow for security auditing.
- Allow for kernel internal use of ftrace instances. Subsystems in
the kernel can now create and destroy their own tracing instances
which allows them to have their own tracing buffer, and be able
to record events without worrying about other users from writing over
their data.
- New seq_buf_hex_dump() that lets users use the hex_dump() in their
seq_buf usage.
- Notifications now added to tracing_max_latency to allow user space
to know when a new max latency is hit by one of the latency tracers.
- Wider spread use of generic compare operations for use of bsearch and
friends.
- More synthetic event fields may be defined (32 up from 16)
- Use of xarray for architectures with sparse system calls, for the
system call trace events.
This along with small clean ups and fixes.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXdwv4BQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qnB5AP91vsdHQjwE1+/UWG/cO+qFtKvn2QJK
QmBRIJNH/s+1TAD/fAOhgw+ojSK3o/qc+NpvPTEW9AEwcJL1wacJUn+XbQc=
=ztql
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"New tracing features:
- New PERMANENT flag to ftrace_ops when attaching a callback to a
function.
As /proc/sys/kernel/ftrace_enabled when set to zero will disable
all attached callbacks in ftrace, this has a detrimental impact on
live kernel tracing, as it disables all that it patched. If a
ftrace_ops is registered to ftrace with the PERMANENT flag set, it
will prevent ftrace_enabled from being disabled, and if
ftrace_enabled is already disabled, it will prevent a ftrace_ops
with PREMANENT flag set from being registered.
- New register_ftrace_direct().
As eBPF would like to register its own trampolines to be called by
the ftrace nop locations directly, without going through the ftrace
trampoline, this function has been added. This allows for eBPF
trampolines to live along side of ftrace, perf, kprobe and live
patching. It also utilizes the ftrace enabled_functions file that
keeps track of functions that have been modified in the kernel, to
allow for security auditing.
- Allow for kernel internal use of ftrace instances.
Subsystems in the kernel can now create and destroy their own
tracing instances which allows them to have their own tracing
buffer, and be able to record events without worrying about other
users from writing over their data.
- New seq_buf_hex_dump() that lets users use the hex_dump() in their
seq_buf usage.
- Notifications now added to tracing_max_latency to allow user space
to know when a new max latency is hit by one of the latency
tracers.
- Wider spread use of generic compare operations for use of bsearch
and friends.
- More synthetic event fields may be defined (32 up from 16)
- Use of xarray for architectures with sparse system calls, for the
system call trace events.
This along with small clean ups and fixes"
* tag 'trace-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (51 commits)
tracing: Enable syscall optimization for MIPS
tracing: Use xarray for syscall trace events
tracing: Sample module to demonstrate kernel access to Ftrace instances.
tracing: Adding new functions for kernel access to Ftrace instances
tracing: Fix Kconfig indentation
ring-buffer: Fix typos in function ring_buffer_producer
ftrace: Use BIT() macro
ftrace: Return ENOTSUPP when DYNAMIC_FTRACE_WITH_DIRECT_CALLS is not configured
ftrace: Rename ftrace_graph_stub to ftrace_stub_graph
ftrace: Add a helper function to modify_ftrace_direct() to allow arch optimization
ftrace: Add helper find_direct_entry() to consolidate code
ftrace: Add another check for match in register_ftrace_direct()
ftrace: Fix accounting bug with direct->count in register_ftrace_direct()
ftrace/selftests: Fix spelling mistake "wakeing" -> "waking"
tracing: Increase SYNTH_FIELDS_MAX for synthetic_events
ftrace/samples: Add a sample module that implements modify_ftrace_direct()
ftrace: Add modify_ftrace_direct()
tracing: Add missing "inline" in stub function of latency_fsnotify()
tracing: Remove stray tab in TRACE_EVAL_MAP_FILE's help text
tracing: Use seq_buf_hex_dump() to dump buffers
...
Here is the "big" set of driver core patches for 5.5-rc1
There's a few minor cleanups and fixes in here, but the majority of the
patches in here fall into two buckets:
- debugfs api cleanups and fixes
- driver core device link support for boot dependancy issues
The debugfs api cleanups are working to slowly refactor the debugfs apis
so that it is even harder to use incorrectly. That work has been
happening for the past few kernel releases and will continue over time,
it's a long-term project/goal
The driver core device link support missed 5.4 by just a bit, so it's
been sitting and baking for many months now. It's from Saravana Kannan
to help resolve the problems that DT-based systems have at boot time
with dependancy graphs and kernel modules. Turns out that no one has
actually tried to build a generic arm64 kernel with loads of modules and
have it "just work" for a variety of platforms (like a distro kernel)
The big problem turned out to be a lack of depandancy information
between different areas of DT entries, and the work here resolves that
problem and now allows devices to boot properly, and quicker than a
monolith kernel.
All of these patches have been in linux-next for a long time with no
reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXd6m6Q8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+yntJQCcCqg6RQ7LTdHuZv1ETeefXlsfk00An1Jtean6
42bWGx52bGFvAcpjWy8R
=P7hq
-----END PGP SIGNATURE-----
Merge tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core updates from Greg KH:
"Here is the "big" set of driver core patches for 5.5-rc1
There's a few minor cleanups and fixes in here, but the majority of
the patches in here fall into two buckets:
- debugfs api cleanups and fixes
- driver core device link support for boot dependancy issues
The debugfs api cleanups are working to slowly refactor the debugfs
apis so that it is even harder to use incorrectly. That work has been
happening for the past few kernel releases and will continue over
time, it's a long-term project/goal
The driver core device link support missed 5.4 by just a bit, so it's
been sitting and baking for many months now. It's from Saravana Kannan
to help resolve the problems that DT-based systems have at boot time
with dependancy graphs and kernel modules. Turns out that no one has
actually tried to build a generic arm64 kernel with loads of modules
and have it "just work" for a variety of platforms (like a distro
kernel). The big problem turned out to be a lack of dependency
information between different areas of DT entries, and the work here
resolves that problem and now allows devices to boot properly, and
quicker than a monolith kernel.
All of these patches have been in linux-next for a long time with no
reported issues"
* tag 'driver-core-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (68 commits)
tracing: Remove unnecessary DEBUG_FS dependency
of: property: Add device link support for interrupt-parent, dmas and -gpio(s)
debugfs: Fix !DEBUG_FS debugfs_create_automount
of: property: Add device link support for "iommu-map"
of: property: Fix the semantics of of_is_ancestor_of()
i2c: of: Populate fwnode in of_i2c_get_board_info()
drivers: base: Fix Kconfig indentation
firmware_loader: Fix labels with comma for builtin firmware
driver core: Allow device link operations inside sync_state()
driver core: platform: Declare ret variable only once
cpu-topology: declare parse_acpi_topology in <linux/arch_topology.h>
crypto: hisilicon: no need to check return value of debugfs_create functions
driver core: platform: use the correct callback type for bus_find_device
firmware_class: make firmware caching configurable
driver core: Clarify documentation for fwnode_operations.add_links()
mailbox: tegra: Fix superfluous IRQ error message
net: caif: Fix debugfs on 64-bit platforms
mac80211: Use debugfs_create_xul() helper
media: c8sectpfe: no need to check return value of debugfs_create functions
of: property: Add device link support for iommus, mboxes and io-channels
...
Set the unoptimized flag after confirming the code is completely
unoptimized. Without this fix, when a kprobe hits the intermediate
modified instruction (the first byte is replaced by an INT3, but
later bytes can still be a jump address operand) while unoptimizing,
it can return to the middle byte of the modified code, which causes
an invalid instruction exception in the kernel.
Usually, this is a rare case, but if we put a probe on the function
call while text patching, it always causes a kernel panic as below:
# echo p text_poke+5 > kprobe_events
# echo 1 > events/kprobes/enable
# echo 0 > events/kprobes/enable
invalid opcode: 0000 [#1] PREEMPT SMP PTI
RIP: 0010:text_poke+0x9/0x50
Call Trace:
arch_unoptimize_kprobe+0x22/0x28
arch_unoptimize_kprobes+0x39/0x87
kprobe_optimizer+0x6e/0x290
process_one_work+0x2a0/0x610
worker_thread+0x28/0x3d0
? process_one_work+0x610/0x610
kthread+0x10d/0x130
? kthread_park+0x80/0x80
ret_from_fork+0x3a/0x50
text_poke() is used for patching the code in optprobes.
This can happen even if we blacklist text_poke() and other functions,
because there is a small time window during which we show the intermediate
code to other CPUs.
[ mingo: Edited the changelog. ]
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Fixes: 6274de4984 ("kprobes: Support delayed unoptimizing")
Link: https://lkml.kernel.org/r/157483422375.25881.13508326028469515760.stgit@devnote2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rework event_create_dir() to use an array of static data instead of
function pointers where possible.
The problem is that it would call the function pointer on module load
before parse_args(), possibly even before jump_labels were initialized.
Luckily the generated functions don't use jump_labels but it still seems
fragile. It also gets in the way of changing when we make the module map
executable.
The generated function are basically calling trace_define_field() with a
bunch of static arguments. So instead of a function, capture these
arguments in a static array, avoiding the function call.
Now there are a number of cases where the fields are dynamic (syscall
arguments, kprobes and uprobes), in which case a static array does not
work, for these we preserve the function call. Luckily all these cases
are not related to modules and so we can retain the function call for
them.
Also fix up all broken tracepoint definitions that now generate a
compile error.
Tested-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111132458.342979914@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Now that there are no users of set_all_modules_text_*() left, remove
it.
While it appears nds32 uses it, it does not have STRICT_MODULE_RWX and
therefore ends up with the NOP stubs.
Tested-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Chen <deanbo422@gmail.com>
Link: https://lkml.kernel.org/r/20191111132458.284298307@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- Use nanoseconds (instead of microseconds) as the unit of time in
the cpuidle core and simplify checks for disabled idle states in
the idle loop (Rafael Wysocki).
- Fix and clean up the teo cpuidle governor (Rafael Wysocki).
- Fix the cpuidle registration error code path (Zhenzhong Duan).
- Avoid excessive vmexits in the ACPI cpuidle driver (Yin Fengwei).
- Extend the idle injection infrastructure to be able to measure the
requested duration in nanoseconds and to allow an exit latency
limit for idle states to be specified (Daniel Lezcano).
- Fix cpufreq driver registration and clarify a comment in the
cpufreq core (Viresh Kumar).
- Add NULL checks to the show() and store() methods of sysfs
attributes exposed by cpufreq (Kai Shen).
- Update cpufreq drivers:
* Fix for a plain int as pointer warning from sparse in
intel_pstate (Jamal Shareef).
* Fix for a hardcoded number of CPUs and stack bloat in the
powernv driver (John Hubbard).
* Updates to the ti-cpufreq driver and DT files to support new
platforms and migrate bindings from opp-v1 to opp-v2 (Adam Ford,
H. Nikolaus Schaller).
* Merging of the arm_big_little and vexpress-spc drivers and
related cleanup (Sudeep Holla).
* Fix for imx's default speed grade value (Anson Huang).
* Minor cleanup of the s3c64xx driver (Nathan Chancellor).
* CPU speed bin detection fix for sun50i (Ondrej Jirman).
- Appoint Chanwoo Choi as the new devfreq maintainer.
- Update the devfreq core:
* Check NULL governor in available_governors_show sysfs to prevent
showing wrong governor information and fix a race condition
between devfreq_update_status() and trans_stat_show() (Leonard
Crestez).
* Add new 'interrupt-driven' flag for devfreq governors to allow
interrupt-driven governors to prevent the devfreq core from
polling devices for status (Dmitry Osipenko).
* Improve an error message in devfreq_add_device() (Matthias
Kaehlcke).
- Update devfreq drivers:
* tegra30 driver fixes and cleanups (Dmitry Osipenko).
* Removal of unused property from dt-binding documentation for
the exynos-bus driver (Kamil Konieczny).
* exynos-ppmu cleanup and DT bindings update (Lukasz Luba, Marek
Szyprowski).
- Add new CPU IDs for CometLake Mobile and Desktop to the Intel RAPL
power capping driver (Zhang Rui).
- Allow device initialization in the generic power domains (genpd)
framework to be more straightforward and clean it up (Ulf Hansson).
- Add support for adjusting OPP voltages at run time to the OPP
framework (Stephen Boyd).
- Avoid freeing memory that has never been allocated in the
hibernation core (Andy Whitcroft).
- Clean up function headers in a header file and coding style in the
wakeup IRQs handling code (Ulf Hansson, Xiaofei Tan).
- Clean up the SmartReflex adaptive voltage scaling (AVS) driver for
ARM (Ben Dooks, Geert Uytterhoeven).
- Wrap power management documentation to fit in 80 columns (Bjorn
Helgaas).
- Add pm-graph utility entry to MAINTAINERS (Todd Brandt).
- Update the cpupower utility:
* Fix the handling of set and info subcommands (Abhishek Goel).
* Fix build warnings (Nathan Chancellor).
* Improve mperf_monitor handling (Janakarajan Natarajan).
-----BEGIN PGP SIGNATURE-----
iQJGBAABCAAwFiEE4fcc61cGeeHD/fCwgsRv/nhiVHEFAl3dHGYSHHJqd0Byand5
c29ja2kubmV0AAoJEILEb/54YlRxMcgP/1bMSkxlRHFOXYSRwS4YcvkUjlBHrCSi
3qGRyYwhc+eRLqRc+2tcmQeQEeQRBqUt8etp7/9WxqS3nic/3Vdf6AFuhSpmJzo1
6JTEutHMU5eP8lwQuKoUCJncCNdIfEOkd5T35E12W/ar5PwyJio0UByZJBnJBjD/
p7/713ucq6ZH95OGncmCJ1S1UslFCZrSS2RRigDInu8gpEssnwN9zwaJbzUYrZHj
BmnKpBpT8FdLmkpbOtmmiT7q2ZGpUEHhkaO916Knf/+BFdvydTXoR90FVvXKy8Zr
QpOxaTdQB2ADifUa5zs8klVP6otmZhEO9vz8hVMUWGziqagObykQngzl8tqrKEBh
hLI8eEG1IkEBCv5ThQbLcoaRXNpwriXXfvWPTPB8s84HJxNZ09F6pXsv1SLh96qC
lj8Q5Yy2a3tlpsg4LB58XoJ54gOtlh8bWKkM0FytrFI/IP+HT4TUu/Rxgp1nDbGd
tKzLvpn4Yo2h10seeDbYk3l79mogUYj50RmwjjPn+9RwS/Df4eIpNb6ibllGZUN/
zcPZH5xlVfQRl2LKDufVN0nYSnoMZY/fU05p9XbUiJWd80LHYOb4Em1N6h/FNOyl
alDhVwlxEvc2BQwL/gjYmN6Qxc7SsPTBrSGVwjWYY+FghOYQd/wBDQqQUeM21QKg
ChOE3z/F/26r
=GJvT
-----END PGP SIGNATURE-----
Merge tag 'pm-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These include cpuidle changes to use nanoseconds (instead of
microseconds) as the unit of time and to simplify checks for disabled
idle states in the idle loop, some cpuidle fixes and governor updates,
assorted cpufreq updates (driver updates mostly and a few core fixes
and cleanups), devfreq updates (dominated by the tegra30 driver
changes), new CPU IDs for the RAPL power capping driver, relatively
minor updates of the generic power domains (genpd) and operation
performance points (OPP) frameworks, and assorted fixes and cleanups.
There are also two maintainer information updates: Chanwoo Choi will
be maintaining the devfreq subsystem going forward and Todd Brandt is
going to maintain the pm-graph utility (created by him).
Specifics:
- Use nanoseconds (instead of microseconds) as the unit of time in
the cpuidle core and simplify checks for disabled idle states in
the idle loop (Rafael Wysocki)
- Fix and clean up the teo cpuidle governor (Rafael Wysocki)
- Fix the cpuidle registration error code path (Zhenzhong Duan)
- Avoid excessive vmexits in the ACPI cpuidle driver (Yin Fengwei)
- Extend the idle injection infrastructure to be able to measure the
requested duration in nanoseconds and to allow an exit latency
limit for idle states to be specified (Daniel Lezcano)
- Fix cpufreq driver registration and clarify a comment in the
cpufreq core (Viresh Kumar)
- Add NULL checks to the show() and store() methods of sysfs
attributes exposed by cpufreq (Kai Shen)
- Update cpufreq drivers:
* Fix for a plain int as pointer warning from sparse in
intel_pstate (Jamal Shareef)
* Fix for a hardcoded number of CPUs and stack bloat in the
powernv driver (John Hubbard)
* Updates to the ti-cpufreq driver and DT files to support new
platforms and migrate bindings from opp-v1 to opp-v2 (Adam Ford,
H. Nikolaus Schaller)
* Merging of the arm_big_little and vexpress-spc drivers and
related cleanup (Sudeep Holla)
* Fix for imx's default speed grade value (Anson Huang)
* Minor cleanup of the s3c64xx driver (Nathan Chancellor)
* CPU speed bin detection fix for sun50i (Ondrej Jirman)
- Appoint Chanwoo Choi as the new devfreq maintainer.
- Update the devfreq core:
* Check NULL governor in available_governors_show sysfs to prevent
showing wrong governor information and fix a race condition
between devfreq_update_status() and trans_stat_show() (Leonard
Crestez)
* Add new 'interrupt-driven' flag for devfreq governors to allow
interrupt-driven governors to prevent the devfreq core from
polling devices for status (Dmitry Osipenko)
* Improve an error message in devfreq_add_device() (Matthias
Kaehlcke)
- Update devfreq drivers:
* tegra30 driver fixes and cleanups (Dmitry Osipenko)
* Removal of unused property from dt-binding documentation for the
exynos-bus driver (Kamil Konieczny)
* exynos-ppmu cleanup and DT bindings update (Lukasz Luba, Marek
Szyprowski)
- Add new CPU IDs for CometLake Mobile and Desktop to the Intel RAPL
power capping driver (Zhang Rui)
- Allow device initialization in the generic power domains (genpd)
framework to be more straightforward and clean it up (Ulf Hansson)
- Add support for adjusting OPP voltages at run time to the OPP
framework (Stephen Boyd)
- Avoid freeing memory that has never been allocated in the
hibernation core (Andy Whitcroft)
- Clean up function headers in a header file and coding style in the
wakeup IRQs handling code (Ulf Hansson, Xiaofei Tan)
- Clean up the SmartReflex adaptive voltage scaling (AVS) driver for
ARM (Ben Dooks, Geert Uytterhoeven)
- Wrap power management documentation to fit in 80 columns (Bjorn
Helgaas)
- Add pm-graph utility entry to MAINTAINERS (Todd Brandt)
- Update the cpupower utility:
* Fix the handling of set and info subcommands (Abhishek Goel)
* Fix build warnings (Nathan Chancellor)
* Improve mperf_monitor handling (Janakarajan Natarajan)"
* tag 'pm-5.5-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (83 commits)
PM: Wrap documentation to fit in 80 columns
cpuidle: Pass exit latency limit to cpuidle_use_deepest_state()
cpuidle: Allow idle injection to apply exit latency limit
cpuidle: Introduce cpuidle_driver_state_disabled() for driver quirks
cpuidle: teo: Avoid code duplication in conditionals
cpufreq: Register drivers only after CPU devices have been registered
cpuidle: teo: Avoid using "early hits" incorrectly
cpuidle: teo: Exclude cpuidle overhead from computations
PM / Domains: Convert to dev_to_genpd_safe() in genpd_syscore_switch()
mmc: tmio: Avoid boilerplate code in ->runtime_suspend()
PM / Domains: Implement the ->start() callback for genpd
PM / Domains: Introduce dev_pm_domain_start()
ARM: OMAP2+: SmartReflex: add omap_sr_pdata definition
PM / wakeirq: remove unnecessary parentheses
power: avs: smartreflex: Remove superfluous cast in debugfs_create_file() call
cpuidle: Use nanoseconds as the unit of time
PM / OPP: Support adjusting OPP voltages at runtime
PM / core: Clean up some function headers in power.h
cpufreq: Add NULL checks to show() and store() methods of cpufreq
cpufreq: intel_pstate: Fix plain int as pointer warning from sparse
...
kernel/bpf/btf.c:4023 btf_distill_func_proto()
error: potentially dereferencing uninitialized 't'.
kernel/bpf/btf.c
4012 nargs = btf_type_vlen(func);
4013 if (nargs >= MAX_BPF_FUNC_ARGS) {
4014 bpf_log(log,
4015 "The function %s has %d arguments. Too many.\n",
4016 tname, nargs);
4017 return -EINVAL;
4018 }
4019 ret = __get_type_size(btf, func->type, &t);
^^
t isn't initialized for the first -EINVAL return
This is unlikely path, since BTF should have been validated at this point.
Fix it by returning 'void' BTF.
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191126230106.237179-1-ast@kernel.org
Pull locking updates from Ingo Molnar:
"The main changes in this cycle were:
- A comprehensive rewrite of the robust/PI futex code's exit handling
to fix various exit races. (Thomas Gleixner et al)
- Rework the generic REFCOUNT_FULL implementation using
atomic_fetch_* operations so that the performance impact of the
cmpxchg() loops is mitigated for common refcount operations.
With these performance improvements the generic implementation of
refcount_t should be good enough for everybody - and this got
confirmed by performance testing, so remove ARCH_HAS_REFCOUNT and
REFCOUNT_FULL entirely, leaving the generic implementation enabled
unconditionally. (Will Deacon)
- Other misc changes, fixes, cleanups"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
lkdtm: Remove references to CONFIG_REFCOUNT_FULL
locking/refcount: Remove unused 'refcount_error_report()' function
locking/refcount: Consolidate implementations of refcount_t
locking/refcount: Consolidate REFCOUNT_{MAX,SATURATED} definitions
locking/refcount: Move saturation warnings out of line
locking/refcount: Improve performance of generic REFCOUNT_FULL code
locking/refcount: Move the bulk of the REFCOUNT_FULL implementation into the <linux/refcount.h> header
locking/refcount: Remove unused refcount_*_checked() variants
locking/refcount: Ensure integer operands are treated as signed
locking/refcount: Define constants for saturation and max refcount values
futex: Prevent exit livelock
futex: Provide distinct return value when owner is exiting
futex: Add mutex around futex exit
futex: Provide state handling for exec() as well
futex: Sanitize exit state handling
futex: Mark the begin of futex exit explicitly
futex: Set task::futex_state to DEAD right after handling futex exit
futex: Split futex_mm_release() for exit/exec
exit/exec: Seperate mm_release()
futex: Replace PF_EXITPIDONE with a state
...
Pull RCU updates from Ingo Molnar:
"The main changes in this cycle were:
- Dynamic tick (nohz) updates, perhaps most notably changes to force
the tick on when needed due to lengthy in-kernel execution on CPUs
on which RCU is waiting.
- Linux-kernel memory consistency model updates.
- Replace rcu_swap_protected() with rcu_prepace_pointer().
- Torture-test updates.
- Documentation updates.
- Miscellaneous fixes"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
security/safesetid: Replace rcu_swap_protected() with rcu_replace_pointer()
net/sched: Replace rcu_swap_protected() with rcu_replace_pointer()
net/netfilter: Replace rcu_swap_protected() with rcu_replace_pointer()
net/core: Replace rcu_swap_protected() with rcu_replace_pointer()
bpf/cgroup: Replace rcu_swap_protected() with rcu_replace_pointer()
fs/afs: Replace rcu_swap_protected() with rcu_replace_pointer()
drivers/scsi: Replace rcu_swap_protected() with rcu_replace_pointer()
drm/i915: Replace rcu_swap_protected() with rcu_replace_pointer()
x86/kvm/pmu: Replace rcu_swap_protected() with rcu_replace_pointer()
rcu: Upgrade rcu_swap_protected() to rcu_replace_pointer()
rcu: Suppress levelspread uninitialized messages
rcu: Fix uninitialized variable in nocb_gp_wait()
rcu: Update descriptions for rcu_future_grace_period tracepoint
rcu: Update descriptions for rcu_nocb_wake tracepoint
rcu: Remove obsolete descriptions for rcu_barrier tracepoint
rcu: Ensure that ->rcu_urgent_qs is set before resched IPI
workqueue: Convert for_each_wq to use built-in list check
rcu: Several rcu_segcblist functions can be static
rcu: Remove unused function hlist_bl_del_init_rcu()
Documentation: Rename rcu_node_context_switch() to rcu_note_context_switch()
...
Pull scheduler updates from Ingo Molnar:
"The biggest changes in this cycle were:
- Make kcpustat vtime aware (Frederic Weisbecker)
- Rework the CFS load_balance() logic (Vincent Guittot)
- Misc cleanups, smaller enhancements, fixes.
The load-balancing rework is the most intrusive change: it replaces
the old heuristics that have become less meaningful after the
introduction of the PELT metrics, with a grounds-up load-balancing
algorithm.
As such it's not really an iterative series, but replaces the old
load-balancing logic with the new one. We hope there are no
performance regressions left - but statistically it's highly probable
that there *is* going to be some workload that is hurting from these
chnages. If so then we'd prefer to have a look at that workload and
fix its scheduling, instead of reverting the changes"
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
rackmeter: Use vtime aware kcpustat accessor
leds: Use all-in-one vtime aware kcpustat accessor
cpufreq: Use vtime aware kcpustat accessors for user time
procfs: Use all-in-one vtime aware kcpustat accessor
sched/vtime: Bring up complete kcpustat accessor
sched/cputime: Support other fields on kcpustat_field()
sched/cpufreq: Move the cfs_rq_util_change() call to cpufreq_update_util()
sched/fair: Add comments for group_type and balancing at SD_NUMA level
sched/fair: Fix rework of find_idlest_group()
sched/uclamp: Fix overzealous type replacement
sched/Kconfig: Fix spelling mistake in user-visible help text
sched/core: Further clarify sched_class::set_next_task()
sched/fair: Use mul_u32_u32()
sched/core: Simplify sched_class::pick_next_task()
sched/core: Optimize pick_next_task()
sched/core: Make pick_next_task_idle() more consistent
sched/fair: Better document newidle_balance()
leds: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM
cpufreq: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM
procfs: Use vtime aware kcpustat accessor to fetch CPUTIME_SYSTEM
...
Pull perf updates from Ingo Molnar:
"The main kernel side changes in this cycle were:
- Various Intel-PT updates and optimizations (Alexander Shishkin)
- Prohibit kprobes on Xen/KVM emulate prefixes (Masami Hiramatsu)
- Add support for LSM and SELinux checks to control access to the
perf syscall (Joel Fernandes)
- Misc other changes, optimizations, fixes and cleanups - see the
shortlog for details.
There were numerous tooling changes as well - 254 non-merge commits.
Here are the main changes - too many to list in detail:
- Enhancements to core tooling infrastructure, perf.data, libperf,
libtraceevent, event parsing, vendor events, Intel PT, callchains,
BPF support and instruction decoding.
- There were updates to the following tools:
perf annotate
perf diff
perf inject
perf kvm
perf list
perf maps
perf parse
perf probe
perf record
perf report
perf script
perf stat
perf test
perf trace
- And a lot of other changes: please see the shortlog and Git log for
more details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (279 commits)
perf parse: Fix potential memory leak when handling tracepoint errors
perf probe: Fix spelling mistake "addrees" -> "address"
libtraceevent: Fix memory leakage in copy_filter_type
libtraceevent: Fix header installation
perf intel-bts: Does not support AUX area sampling
perf intel-pt: Add support for decoding AUX area samples
perf intel-pt: Add support for recording AUX area samples
perf pmu: When using default config, record which bits of config were changed by the user
perf auxtrace: Add support for queuing AUX area samples
perf session: Add facility to peek at all events
perf auxtrace: Add support for dumping AUX area samples
perf inject: Cut AUX area samples
perf record: Add aux-sample-size config term
perf record: Add support for AUX area sampling
perf auxtrace: Add support for AUX area sample recording
perf auxtrace: Move perf_evsel__find_pmu()
perf record: Add a function to test for kernel support for AUX area sampling
perf tools: Add kernel AUX area sampling definitions
perf/core: Make the mlock accounting simple again
perf report: Jump to symbol source view from total cycles view
...
Pull stacktrace cleanup from Ingo Molnar:
"A minor cleanup"
* 'core-stacktrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stacktrace: Get rid of unneeded '!!' pattern
This system call has been deprecated almost since it was introduced, and
in a survey of the linux distributions I can no longer find any of them
that enable CONFIG_SYSCTL_SYSCALL. The only indication that I can find
that anyone might care is that a few of the defconfigs in the kernel
enable CONFIG_SYSCTL_SYSCALL. However this appears in only 31 of 414
defconfigs in the kernel, so I suspect this symbols presence is simply
because it is harmless to include rather than because it is necessary.
As there appear to be no users of the sysctl system call, remove the
code. As this removes one of the few uses of the internal kernel mount
of proc I hope this allows for even more simplifications of the proc
filesystem.
Cc: Alex Smith <alex.smith@imgtec.com>
Cc: Anders Berg <anders.berg@lsi.com>
Cc: Apelete Seketeli <apelete@seketeli.net>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Chee Nouk Phoon <cnphoon@altera.com>
Cc: Chris Zankel <chris@zankel.net>
Cc: Christian Ruppert <christian.ruppert@abilis.com>
Cc: Greg Ungerer <gerg@uclinux.org>
Cc: Harvey Hunt <harvey.hunt@imgtec.com>
Cc: Helge Deller <deller@gmx.de>
Cc: Hongliang Tao <taohl@lemote.com>
Cc: Hua Yan <yanh@lemote.com>
Cc: Huacai Chen <chenhc@lemote.com>
Cc: John Crispin <blogic@openwrt.org>
Cc: Jonas Jensen <jonas.jensen@gmail.com>
Cc: Josh Boyer <jwboyer@gmail.com>
Cc: Jun Nie <jun.nie@linaro.org>
Cc: Kevin Hilman <khilman@linaro.org>
Cc: Kevin Wells <kevin.wells@nxp.com>
Cc: Kumar Gala <galak@codeaurora.org>
Cc: Lars-Peter Clausen <lars@metafoo.de>
Cc: Ley Foon Tan <lftan@altera.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Markos Chandras <markos.chandras@imgtec.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Noam Camus <noamc@ezchip.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mundt <lethal@linux-sh.org>
Cc: Phil Edworthy <phil.edworthy@renesas.com>
Cc: Pierrick Hascoet <pierrick.hascoet@abilis.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Roland Stigge <stigge@antcom.de>
Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Scott Telford <stelford@cadence.com>
Cc: Stephen Boyd <sboyd@codeaurora.org>
Cc: Steven J. Hill <Steven.Hill@imgtec.com>
Cc: Tanmay Inamdar <tinamdar@apm.com>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Wolfram Sang <w.sang@pengutronix.de>
Acked-by: Andi Kleen <ak@linux.intel.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
* pm-sleep:
PM / wakeirq: remove unnecessary parentheses
PM / core: Clean up some function headers in power.h
PM / hibernate: memory_bm_find_bit(): Tighten node optimisation
* pm-domains:
PM / Domains: Convert to dev_to_genpd_safe() in genpd_syscore_switch()
mmc: tmio: Avoid boilerplate code in ->runtime_suspend()
PM / Domains: Implement the ->start() callback for genpd
PM / Domains: Introduce dev_pm_domain_start()
* pm-opp:
PM / OPP: Support adjusting OPP voltages at runtime
* powercap:
powercap/intel_rapl: add support for Cometlake desktop
powercap/intel_rapl: add support for CometLake Mobile
* pm-cpuidle:
cpuidle: Pass exit latency limit to cpuidle_use_deepest_state()
cpuidle: Allow idle injection to apply exit latency limit
cpuidle: Introduce cpuidle_driver_state_disabled() for driver quirks
cpuidle: teo: Avoid code duplication in conditionals
cpuidle: teo: Avoid using "early hits" incorrectly
cpuidle: teo: Exclude cpuidle overhead from computations
cpuidle: Use nanoseconds as the unit of time
cpuidle: Consolidate disabled state checks
ACPI: processor_idle: Skip dummy wait if kernel is in guest
cpuidle: Do not unset the driver if it is there already
cpuidle: teo: Fix "early hits" handling for disabled idle states
cpuidle: teo: Consider hits and misses metrics of disabled states
cpuidle: teo: Rename local variable in teo_select()
cpuidle: teo: Ignore disabled idle states that are too deep
Pull networking updates from David Miller:
"Another merge window, another pull full of stuff:
1) Support alternative names for network devices, from Jiri Pirko.
2) Introduce per-netns netdev notifiers, also from Jiri Pirko.
3) Support MSG_PEEK in vsock/virtio, from Matias Ezequiel Vara
Larsen.
4) Allow compiling out the TLS TOE code, from Jakub Kicinski.
5) Add several new tracepoints to the kTLS code, also from Jakub.
6) Support set channels ethtool callback in ena driver, from Sameeh
Jubran.
7) New SCTP events SCTP_ADDR_ADDED, SCTP_ADDR_REMOVED,
SCTP_ADDR_MADE_PRIM, and SCTP_SEND_FAILED_EVENT. From Xin Long.
8) Add XDP support to mvneta driver, from Lorenzo Bianconi.
9) Lots of netfilter hw offload fixes, cleanups and enhancements,
from Pablo Neira Ayuso.
10) PTP support for aquantia chips, from Egor Pomozov.
11) Add UDP segmentation offload support to igb, ixgbe, and i40e. From
Josh Hunt.
12) Add smart nagle to tipc, from Jon Maloy.
13) Support L2 field rewrite by TC offloads in bnxt_en, from Venkat
Duvvuru.
14) Add a flow mask cache to OVS, from Tonghao Zhang.
15) Add XDP support to ice driver, from Maciej Fijalkowski.
16) Add AF_XDP support to ice driver, from Krzysztof Kazimierczak.
17) Support UDP GSO offload in atlantic driver, from Igor Russkikh.
18) Support it in stmmac driver too, from Jose Abreu.
19) Support TIPC encryption and auth, from Tuong Lien.
20) Introduce BPF trampolines, from Alexei Starovoitov.
21) Make page_pool API more numa friendly, from Saeed Mahameed.
22) Introduce route hints to ipv4 and ipv6, from Paolo Abeni.
23) Add UDP segmentation offload to cxgb4, Rahul Lakkireddy"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1857 commits)
libbpf: Fix usage of u32 in userspace code
mm: Implement no-MMU variant of vmalloc_user_node_flags
slip: Fix use-after-free Read in slip_open
net: dsa: sja1105: fix sja1105_parse_rgmii_delays()
macvlan: schedule bc_work even if error
enetc: add support Credit Based Shaper(CBS) for hardware offload
net: phy: add helpers phy_(un)lock_mdio_bus
mdio_bus: don't use managed reset-controller
ax88179_178a: add ethtool_op_get_ts_info()
mlxsw: spectrum_router: Fix use of uninitialized adjacency index
mlxsw: spectrum_router: After underlay moves, demote conflicting tunnels
bpf: Simplify __bpf_arch_text_poke poke type handling
bpf: Introduce BPF_TRACE_x helper for the tracing tests
bpf: Add bpf_jit_blinding_enabled for !CONFIG_BPF_JIT
bpf, testing: Add various tail call test cases
bpf, x86: Emit patchable direct jump as tail call
bpf: Constant map key tracking for prog array pokes
bpf: Add poke dependency tracking for prog array maps
bpf: Add initial poke descriptor table for jit images
bpf: Move owner type, jited info into array auxiliary data
...
-----BEGIN PGP SIGNATURE-----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=i37E
-----END PGP SIGNATURE-----
Merge tag 'livepatching-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching
Pull livepatching updates from Petr Mladek:
- New API to track system state changes done be livepatch callbacks. It
helps to maintain compatibility between livepatches.
- Update Kconfig help text. ORC is another reliable unwinder.
- Disable generic selftest timeout. Livepatch selftests have their own
per-operation fine-grained timeouts.
* tag 'livepatching-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
x86/stacktrace: update kconfig help text for reliable unwinders
livepatch: Selftests of the API for tracking system state changes
livepatch: Documentation of the new API for tracking system state changes
livepatch: Allow to distinguish different version of system state changes
livepatch: Basic API to track system state changes
livepatch: Keep replaced patches until post_patch callback is called
selftests/livepatch: Disable the timeout
-----BEGIN PGP SIGNATURE-----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=QCEy
-----END PGP SIGNATURE-----
Merge tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:
- Allow to print symbolic error names via new %pe modifier.
- Use pr_warn() instead of the remaining pr_warning() calls. Fix
formatting of the related lines.
- Add VSPRINTF entry to MAINTAINERS.
* tag 'printk-for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk: (32 commits)
checkpatch: don't warn about new vsprintf pointer extension '%pe'
MAINTAINERS: Add VSPRINTF
tools lib api: Renaming pr_warning to pr_warn
ASoC: samsung: Use pr_warn instead of pr_warning
lib: cpu_rmap: Use pr_warn instead of pr_warning
trace: Use pr_warn instead of pr_warning
dma-debug: Use pr_warn instead of pr_warning
vgacon: Use pr_warn instead of pr_warning
fs: afs: Use pr_warn instead of pr_warning
sh/intc: Use pr_warn instead of pr_warning
scsi: Use pr_warn instead of pr_warning
platform/x86: intel_oaktrail: Use pr_warn instead of pr_warning
platform/x86: asus-laptop: Use pr_warn instead of pr_warning
platform/x86: eeepc-laptop: Use pr_warn instead of pr_warning
oprofile: Use pr_warn instead of pr_warning
of: Use pr_warn instead of pr_warning
macintosh: Use pr_warn instead of pr_warning
idsn: Use pr_warn instead of pr_warning
ide: Use pr_warn instead of pr_warning
crypto: n2: Use pr_warn instead of pr_warning
...
Pull cgroup updates from Tejun Heo:
"There are several notable changes here:
- Single thread migrating itself has been optimized so that it
doesn't need threadgroup rwsem anymore.
- Freezer optimization to avoid unnecessary frozen state changes.
- cgroup ID unification so that cgroup fs ino is the only unique ID
used for the cgroup and can be used to directly look up live
cgroups through filehandle interface on 64bit ino archs. On 32bit
archs, cgroup fs ino is still the only ID in use but it is only
unique when combined with gen.
- selftest and other changes"
* 'for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (24 commits)
writeback: fix -Wformat compilation warnings
docs: cgroup: mm: Fix spelling of "list"
cgroup: fix incorrect WARN_ON_ONCE() in cgroup_setup_root()
cgroup: use cgrp->kn->id as the cgroup ID
kernfs: use 64bit inos if ino_t is 64bit
kernfs: implement custom exportfs ops and fid type
kernfs: combine ino/id lookup functions into kernfs_find_and_get_node_by_id()
kernfs: convert kernfs_node->id from union kernfs_node_id to u64
kernfs: kernfs_find_and_get_node_by_ino() should only look up activated nodes
kernfs: use dumber locking for kernfs_find_and_get_node_by_ino()
netprio: use css ID instead of cgroup ID
writeback: use ino_t for inodes in tracepoints
kernfs: fix ino wrap-around detection
kselftests: cgroup: Avoid the reuse of fd after it is deallocated
cgroup: freezer: don't change task and cgroups status unnecessarily
cgroup: use cgroup->last_bstat instead of cgroup->bstat_pending for consistency
cgroup: remove cgroup_enable_task_cg_lists() optimization
cgroup: pids: use atomic64_t for pids->limit
selftests: cgroup: Run test_core under interfering stress
selftests: cgroup: Add task migration tests
...
Pull workqueue updates from Tejun Heo:
"There have been sporadic reports of sanity checks in
destroy_workqueue() failing spuriously over the years. This contains
the fix and its follow-up changes / fixes.
There's also a RCU annotation improvement"
* 'for-5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Add RCU annotation for pwq list walk
workqueue: Fix pwq ref leak in rescuer_thread()
workqueue: more destroy_workqueue() fixes
workqueue: Minor follow-ups to the rescuer destruction change
workqueue: Fix missing kfree(rescuer) in destroy_workqueue()
workqueue: Fix spurious sanity check failures in destroy_workqueue()
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXdfjBwAKCRCRxhvAZXjc
onCBAP47WZ/ie7yjoDWhOI1QB7II3NGSzToakxpgJaWoB+NjTwEA7PGrSYVEbPrf
pUhiEaEJ29t+cWUxX3+yDO+k7SA6BAY=
=Ra58
-----END PGP SIGNATURE-----
Merge tag 'threads-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread management updates from Christian Brauner:
- A pidfd's fdinfo file currently contains the field "Pid:\t<pid>"
where <pid> is the pid of the process in the pid namespace of the
procfs instance the fdinfo file for the pidfd was opened in.
The fdinfo file has now gained a new "NSpid:\t<ns-pid1>[\t<ns-pid2>[...]]"
field which lists the pids of the process in all child pid namespaces
provided the pid namespace of the procfs instance it is looked up
under has an ancestoral relationship with the pid namespace of the
process. If it does not 0 will be shown and no further pid namespaces
will be listed. Tests included. (Christian Kellner)
- If the process the pidfd references has already exited, print -1 for
the Pid and NSpid fields in the pidfd's fdinfo file. Tests included.
(me)
- Add CLONE_CLEAR_SIGHAND. This lets callers clear all signal handler
that are not SIG_DFL or SIG_IGN at process creation time. This
originated as a feature request from glibc to improve performance and
elimate races in their posix_spawn() implementation. Tests included.
(me)
- Add support for choosing a specific pid for a process with clone3().
This is the feature which was part of the thread update for v5.4 but
after a discussion at LPC in Lisbon we decided to delay it for one
more cycle in order to make the interface more generic. This has now
done. It is now possible to choose a specific pid in a whole pid
namespaces (sub)hierarchy instead of just one pid namespace. In order
to choose a specific pid the caller must have CAP_SYS_ADMIN in all
owning user namespaces of the target pid namespaces. Tests included.
(Adrian Reber)
- Test improvements and extensions. (Andrei Vagin, me)
* tag 'threads-v5.5' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests/clone3: skip if clone3() is ENOSYS
selftests/clone3: check that all pids are released on error paths
selftests/clone3: report a correct number of fails
selftests/clone3: flush stdout and stderr before clone3() and _exit()
selftests: add tests for clone3() with *set_tid
fork: extend clone3() to support setting a PID
selftests: add tests for clone3()
tests: test CLONE_CLEAR_SIGHAND
clone3: add CLONE_CLEAR_SIGHAND
pid: use pid_has_task() in pidfd_open()
exit: use pid_has_task() in do_wait()
pid: use pid_has_task() in __change_pid()
test: verify fdinfo for pidfd of reaped process
pidfd: check pid has attached task in fdinfo
pidfd: add tests for NSpid info in fdinfo
pidfd: add NSpid entries to fdinfo
- Data abort report and injection
- Steal time support
- GICv4 performance improvements
- vgic ITS emulation fixes
- Simplify FWB handling
- Enable halt polling counters
- Make the emulated timer PREEMPT_RT compliant
s390:
- Small fixes and cleanups
- selftest improvements
- yield improvements
PPC:
- Add capability to tell userspace whether we can single-step the guest.
- Improve the allocation of XIVE virtual processor IDs
- Rewrite interrupt synthesis code to deliver interrupts in virtual
mode when appropriate.
- Minor cleanups and improvements.
x86:
- XSAVES support for AMD
- more accurate report of nested guest TSC to the nested hypervisor
- retpoline optimizations
- support for nested 5-level page tables
- PMU virtualization optimizations, and improved support for nested
PMU virtualization
- correct latching of INITs for nested virtualization
- IOAPIC optimization
- TSX_CTRL virtualization for more TAA happiness
- improved allocation and flushing of SEV ASIDs
- many bugfixes and cleanups
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJd27PMAAoJEL/70l94x66DspsH+gPc6YWtKJFJH58Zj8NrNh6y
t0FwDFcvUa51+m4jaY4L5Y8+zqu1dZFnPPhFGqNWpxrjCEvE/glQJv3BiUX06Seh
aYUHNymGoYCTJOHaaGhV+NlgQaDuZOCOkIsOLAPehyFd1KojwB+FRC0xmO6aROPw
9yQgYrKuK1UUn5HwxBNrMS4+Xv+2iKv/9sTnq1G4W2qX2NZQg84LVPg1zIdkCh3D
3GOvoCBEk3ivQqjmdE7rP/InPr0XvW0b6TFhchIk8J6jEIQFHsmOUefiTvTxsIHV
OKAZwvyeYPrYHA/aDZpaBmY2aR0ydfKDUQcviNIJoF1vOktGs0hvl3VbsmG8QCg=
=OSI1
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"ARM:
- data abort report and injection
- steal time support
- GICv4 performance improvements
- vgic ITS emulation fixes
- simplify FWB handling
- enable halt polling counters
- make the emulated timer PREEMPT_RT compliant
s390:
- small fixes and cleanups
- selftest improvements
- yield improvements
PPC:
- add capability to tell userspace whether we can single-step the
guest
- improve the allocation of XIVE virtual processor IDs
- rewrite interrupt synthesis code to deliver interrupts in virtual
mode when appropriate.
- minor cleanups and improvements.
x86:
- XSAVES support for AMD
- more accurate report of nested guest TSC to the nested hypervisor
- retpoline optimizations
- support for nested 5-level page tables
- PMU virtualization optimizations, and improved support for nested
PMU virtualization
- correct latching of INITs for nested virtualization
- IOAPIC optimization
- TSX_CTRL virtualization for more TAA happiness
- improved allocation and flushing of SEV ASIDs
- many bugfixes and cleanups"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (127 commits)
kvm: nVMX: Relax guest IA32_FEATURE_CONTROL constraints
KVM: x86: Grab KVM's srcu lock when setting nested state
KVM: x86: Open code shared_msr_update() in its only caller
KVM: Fix jump label out_free_* in kvm_init()
KVM: x86: Remove a spurious export of a static function
KVM: x86: create mmu/ subdirectory
KVM: nVMX: Remove unnecessary TLB flushes on L1<->L2 switches when L1 use apic-access-page
KVM: x86: remove set but not used variable 'called'
KVM: nVMX: Do not mark vmcs02->apic_access_page as dirty when unpinning
KVM: vmx: use MSR_IA32_TSX_CTRL to hard-disable TSX on guest that lack it
KVM: vmx: implement MSR_IA32_TSX_CTRL disable RTM functionality
KVM: x86: implement MSR_IA32_TSX_CTRL effect on CPUID
KVM: x86: do not modify masked bits of shared MSRs
KVM: x86: fix presentation of TSX feature in ARCH_CAPABILITIES
KVM: PPC: Book3S HV: XIVE: Fix potential page leak on error path
KVM: PPC: Book3S HV: XIVE: Free previous EQ page when setting up a new one
KVM: nVMX: Assume TLB entries of L1 and L2 are tagged differently if L0 use EPT
KVM: x86: Unexport kvm_vcpu_reload_apic_access_page()
KVM: nVMX: add CR4_LA57 bit to nested CR4_FIXED1
KVM: nVMX: Use semi-colon instead of comma for exit-handlers initialization
...
- On ARMv8 CPUs without hardware updates of the access flag, avoid
failing cow_user_page() on PFN mappings if the pte is old. The patches
introduce an arch_faults_on_old_pte() macro, defined as false on x86.
When true, cow_user_page() makes the pte young before attempting
__copy_from_user_inatomic().
- Covert the synchronous exception handling paths in
arch/arm64/kernel/entry.S to C.
- FTRACE_WITH_REGS support for arm64.
- ZONE_DMA re-introduced on arm64 to support Raspberry Pi 4
- Several kselftest cases specific to arm64, together with a MAINTAINERS
update for these files (moved to the ARM64 PORT entry).
- Workaround for a Neoverse-N1 erratum where the CPU may fetch stale
instructions under certain conditions.
- Workaround for Cortex-A57 and A72 errata where the CPU may
speculatively execute an AT instruction and associate a VMID with the
wrong guest page tables (corrupting the TLB).
- Perf updates for arm64: additional PMU topologies on HiSilicon
platforms, support for CCN-512 interconnect, AXI ID filtering in the
IMX8 DDR PMU, support for the CCPI2 uncore PMU in ThunderX2.
- GICv3 optimisation to avoid a heavy barrier when accessing the
ICC_PMR_EL1 register.
- ELF HWCAP documentation updates and clean-up.
- SMC calling convention conduit code clean-up.
- KASLR diagnostics printed during boot
- NVIDIA Carmel CPU added to the KPTI whitelist
- Some arm64 mm clean-ups: use generic free_initrd_mem(), remove stale
macro, simplify calculation in __create_pgd_mapping(), typos.
- Kconfig clean-ups: CMDLINE_FORCE to depend on CMDLINE, choice for
endinanness to help with allmodconfig.
-----BEGIN PGP SIGNATURE-----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=TPL9
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
"Apart from the arm64-specific bits (core arch and perf, new arm64
selftests), it touches the generic cow_user_page() (reviewed by
Kirill) together with a macro for x86 to preserve the existing
behaviour on this architecture.
Summary:
- On ARMv8 CPUs without hardware updates of the access flag, avoid
failing cow_user_page() on PFN mappings if the pte is old. The
patches introduce an arch_faults_on_old_pte() macro, defined as
false on x86. When true, cow_user_page() makes the pte young before
attempting __copy_from_user_inatomic().
- Covert the synchronous exception handling paths in
arch/arm64/kernel/entry.S to C.
- FTRACE_WITH_REGS support for arm64.
- ZONE_DMA re-introduced on arm64 to support Raspberry Pi 4
- Several kselftest cases specific to arm64, together with a
MAINTAINERS update for these files (moved to the ARM64 PORT entry).
- Workaround for a Neoverse-N1 erratum where the CPU may fetch stale
instructions under certain conditions.
- Workaround for Cortex-A57 and A72 errata where the CPU may
speculatively execute an AT instruction and associate a VMID with
the wrong guest page tables (corrupting the TLB).
- Perf updates for arm64: additional PMU topologies on HiSilicon
platforms, support for CCN-512 interconnect, AXI ID filtering in
the IMX8 DDR PMU, support for the CCPI2 uncore PMU in ThunderX2.
- GICv3 optimisation to avoid a heavy barrier when accessing the
ICC_PMR_EL1 register.
- ELF HWCAP documentation updates and clean-up.
- SMC calling convention conduit code clean-up.
- KASLR diagnostics printed during boot
- NVIDIA Carmel CPU added to the KPTI whitelist
- Some arm64 mm clean-ups: use generic free_initrd_mem(), remove
stale macro, simplify calculation in __create_pgd_mapping(), typos.
- Kconfig clean-ups: CMDLINE_FORCE to depend on CMDLINE, choice for
endinanness to help with allmodconfig"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (93 commits)
arm64: Kconfig: add a choice for endianness
kselftest: arm64: fix spelling mistake "contiguos" -> "contiguous"
arm64: Kconfig: make CMDLINE_FORCE depend on CMDLINE
MAINTAINERS: Add arm64 selftests to the ARM64 PORT entry
arm64: kaslr: Check command line before looking for a seed
arm64: kaslr: Announce KASLR status on boot
kselftest: arm64: fake_sigreturn_misaligned_sp
kselftest: arm64: fake_sigreturn_bad_size
kselftest: arm64: fake_sigreturn_duplicated_fpsimd
kselftest: arm64: fake_sigreturn_missing_fpsimd
kselftest: arm64: fake_sigreturn_bad_size_for_magic0
kselftest: arm64: fake_sigreturn_bad_magic
kselftest: arm64: add helper get_current_context
kselftest: arm64: extend test_init functionalities
kselftest: arm64: mangle_pstate_invalid_mode_el[123][ht]
kselftest: arm64: mangle_pstate_invalid_daif_bits
kselftest: arm64: mangle_pstate_invalid_compat_toggle and common utils
kselftest: arm64: extend toplevel skeleton Makefile
drivers/perf: hisi: update the sccl_id/ccl_id for certain HiSilicon platform
arm64: mm: reserve CMA and crashkernel in ZONE_DMA32
...
This kselftest update for Linux 5.5-rc1 adds KUnit, a lightweight unit
testing and mocking framework for the Linux kernel from Brendan Higgins.
KUnit is not an end-to-end testing framework. It is currently supported
on UML and sub-systems can write unit tests and run them in UML env.
KUnit documentation is included in this update.
In addition, this Kunit update adds 3 new kunit tests:
- kunit test for proc sysctl from Iurii Zaikin
- kunit test for the 'list' doubly linked list from David Gow
- ext4 kunit test for decoding extended timestamps from Iurii Zaikin
In the future KUnit will be linked to Kselftest framework to provide
a way to trigger KUnit tests from user-space.
-----BEGIN PGP SIGNATURE-----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=0zEe
-----END PGP SIGNATURE-----
Merge tag 'linux-kselftest-5.5-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest
Pull kselftest KUnit support gtom Shuah Khan:
"This adds KUnit, a lightweight unit testing and mocking framework for
the Linux kernel from Brendan Higgins.
KUnit is not an end-to-end testing framework. It is currently
supported on UML and sub-systems can write unit tests and run them in
UML env. KUnit documentation is included in this update.
In addition, this Kunit update adds 3 new kunit tests:
- proc sysctl test from Iurii Zaikin
- the 'list' doubly linked list test from David Gow
- ext4 tests for decoding extended timestamps from Iurii Zaikin
In the future KUnit will be linked to Kselftest framework to provide a
way to trigger KUnit tests from user-space"
* tag 'linux-kselftest-5.5-rc1-kunit' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest: (23 commits)
lib/list-test: add a test for the 'list' doubly linked list
ext4: add kunit test for decoding extended timestamps
Documentation: kunit: Fix verification command
kunit: Fix '--build_dir' option
kunit: fix failure to build without printk
MAINTAINERS: add proc sysctl KUnit test to PROC SYSCTL section
kernel/sysctl-test: Add null pointer test for sysctl.c:proc_dointvec()
MAINTAINERS: add entry for KUnit the unit testing framework
Documentation: kunit: add documentation for KUnit
kunit: defconfig: add defconfigs for building KUnit tests
kunit: tool: add Python wrappers for running KUnit tests
kunit: test: add tests for KUnit managed resources
kunit: test: add the concept of assertions
kunit: test: add tests for kunit test abort
kunit: test: add support for test abort
objtool: add kunit_try_catch_throw to the noreturn list
kunit: test: add initial tests
lib: enable building KUnit in lib/
kunit: test: add the concept of expectations
kunit: test: add assertion printing library
...
Changing alarm_itimer accidentally broke the logic for arithmetic
rounding of half seconds in the return code.
Change it to a constant based on NSEC_PER_SEC, as suggested by
Ben Hutchings.
Fixes: bd40a17576 ("y2038: itimer: change implementation to timespec64")
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
-----BEGIN PGP SIGNATURE-----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=YZ9s
-----END PGP SIGNATURE-----
Merge tag 'for-5.5/io_uring-20191121' of git://git.kernel.dk/linux-block
Pull io_uring updates from Jens Axboe:
"A lot of stuff has been going on this cycle, with improving the
support for networked IO (and hence unbounded request completion
times) being one of the major themes. There's been a set of fixes done
this week, I'll send those out as well once we're certain we're fully
happy with them.
This contains:
- Unification of the "normal" submit path and the SQPOLL path (Pavel)
- Support for sparse (and bigger) file sets, and updating of those
file sets without needing to unregister/register again.
- Independently sized CQ ring, instead of just making it always 2x
the SQ ring size. This makes it more flexible for networked
applications.
- Support for overflowed CQ ring, never dropping events but providing
backpressure on submits.
- Add support for absolute timeouts, not just relative ones.
- Support for generic cancellations. This divorces io_uring from
workqueues as well, which additionally gets us one step closer to
generic async system call support.
- With cancellations, we can support grabbing the process file table
as well, just like we do mm context. This allows support for system
calls that create file descriptors, like accept4() support that's
built on top of that.
- Support for io_uring tracing (Dmitrii)
- Support for linked timeouts. These abort an operation if it isn't
completed by the time noted in the linke timeout.
- Speedup tracking of poll requests
- Various cleanups making the coder easier to follow (Jackie, Pavel,
Bob, YueHaibing, me)
- Update MAINTAINERS with new io_uring list"
* tag 'for-5.5/io_uring-20191121' of git://git.kernel.dk/linux-block: (64 commits)
io_uring: make POLL_ADD/POLL_REMOVE scale better
io-wq: remove now redundant struct io_wq_nulls_list
io_uring: Fix getting file for non-fd opcodes
io_uring: introduce req_need_defer()
io_uring: clean up io_uring_cancel_files()
io-wq: ensure free/busy list browsing see all items
io-wq: ensure we have a stable view of ->cur_work for cancellations
io_wq: add get/put_work handlers to io_wq_create()
io_uring: check for validity of ->rings in teardown
io_uring: fix potential deadlock in io_poll_wake()
io_uring: use correct "is IO worker" helper
io_uring: fix -ENOENT issue with linked timer with short timeout
io_uring: don't do flush cancel under inflight_lock
io_uring: flag SQPOLL busy condition to userspace
io_uring: make ASYNC_CANCEL work with poll and timeout
io_uring: provide fallback request for OOM situations
io_uring: convert accept4() -ERESTARTSYS into -EINTR
io_uring: fix error clear of ->file_table in io_sqe_files_register()
io_uring: separate the io_free_req and io_free_req_find_next interface
io_uring: keep io_put_req only responsible for release and put req
...
Given that we have BPF_MOD_NOP_TO_{CALL,JUMP}, BPF_MOD_{CALL,JUMP}_TO_NOP
and BPF_MOD_{CALL,JUMP}_TO_{CALL,JUMP} poke types and that we also pass in
old_addr as well as new_addr, it's a bit redundant and unnecessarily
complicates __bpf_arch_text_poke() itself since we can derive the same from
the *_addr that were passed in. Hence simplify and use BPF_MOD_{CALL,JUMP}
as types which also allows to clean up call-sites.
In addition to that, __bpf_arch_text_poke() currently verifies that text
matches expected old_insn before we invoke text_poke_bp(). Also add a check
on new_insn and skip rewrite if it already matches. Reason why this is rather
useful is that it avoids making any special casing in prog_array_map_poke_run()
when old and new prog were NULL and has the benefit that also for this case
we perform a check on text whether it really matches our expectations.
Suggested-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/fcb00a2b0b288d6c73de4ef58116a821c8fe8f2f.1574555798.git.daniel@iogearbox.net
Add tracking of constant keys into tail call maps. The signature of
bpf_tail_call_proto is that arg1 is ctx, arg2 map pointer and arg3
is a index key. The direct call approach for tail calls can be enabled
if the verifier asserted that for all branches leading to the tail call
helper invocation, the map pointer and index key were both constant
and the same.
Tracking of map pointers we already do from prior work via c93552c443
("bpf: properly enforce index mask to prevent out-of-bounds speculation")
and 09772d92cd ("bpf: avoid retpoline for lookup/update/ delete calls
on maps").
Given the tail call map index key is not on stack but directly in the
register, we can add similar tracking approach and later in fixup_bpf_calls()
add a poke descriptor to the progs poke_tab with the relevant information
for the JITing phase.
We internally reuse insn->imm for the rewritten BPF_JMP | BPF_TAIL_CALL
instruction in order to point into the prog's poke_tab, and keep insn->imm
as 0 as indicator that current indirect tail call emission must be used.
Note that publishing to the tracker must happen at the end of fixup_bpf_calls()
since adding elements to the poke_tab reallocates its memory, so we need
to wait until its in final state.
Future work can generalize and add similar approach to optimize plain
array map lookups. Difference there is that we need to look into the key
value that sits on stack. For clarity in bpf_insn_aux_data, map_state
has been renamed into map_ptr_state, so we get map_{ptr,key}_state as
trackers.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/e8db37f6b2ae60402fa40216c96738ee9b316c32.1574452833.git.daniel@iogearbox.net
This work adds program tracking to prog array maps. This is needed such
that upon prog array updates/deletions we can fix up all programs which
make use of this tail call map. We add ops->map_poke_{un,}track()
helpers to maps to maintain the list of programs and ops->map_poke_run()
for triggering the actual update.
bpf_array_aux is extended to contain the list head and poke_mutex in
order to serialize program patching during updates/deletions.
bpf_free_used_maps() will untrack the program shortly before dropping
the reference to the map. For clearing out the prog array once all urefs
are dropped we need to use schedule_work() to have a sleepable context.
The prog_array_map_poke_run() is triggered during updates/deletions and
walks the maintained prog list. It checks in their poke_tabs whether the
map and key is matching and runs the actual bpf_arch_text_poke() for
patching in the nop or new jmp location. Depending on the type of update,
we use one of BPF_MOD_{NOP_TO_JUMP,JUMP_TO_NOP,JUMP_TO_JUMP}.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1fb364bb3c565b3e415d5ea348f036ff379e779d.1574452833.git.daniel@iogearbox.net
Add initial poke table data structures and management to the BPF
prog that can later be used by JITs. Also add an instance of poke
specific data for tail call maps; plan for later work is to extend
this also for BPF static keys.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/1db285ec2ea4207ee0455b3f8e191a4fc58b9ade.1574452833.git.daniel@iogearbox.net
We're going to extend this with further information which is only
relevant for prog array at this point. Given this info is not used
in critical path, move it into its own structure such that the main
array map structure can be kept on diet.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/b9ddccdb0f6f7026489ee955f16c96381e1e7238.1574452833.git.daniel@iogearbox.net
We later on are going to need a sleepable context as opposed to plain
RCU callback in order to untrack programs we need to poke at runtime
and tracking as well as image update is performed under mutex.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/09823b1d5262876e9b83a8e75df04cf0467357a4.1574452833.git.daniel@iogearbox.net
With latest llvm (trunk https://github.com/llvm/llvm-project),
test_progs, which has +alu32 enabled, failed for strobemeta.o.
The verifier output looks like below with edit to replace large
decimal numbers with hex ones.
193: (85) call bpf_probe_read_user_str#114
R0=inv(id=0)
194: (26) if w0 > 0x1 goto pc+4
R0_w=inv(id=0,umax_value=0xffffffff00000001)
195: (6b) *(u16 *)(r7 +80) = r0
196: (bc) w6 = w0
R6_w=inv(id=0,umax_value=0xffffffff,var_off=(0x0; 0xffffffff))
197: (67) r6 <<= 32
R6_w=inv(id=0,smax_value=0x7fffffff00000000,umax_value=0xffffffff00000000,
var_off=(0x0; 0xffffffff00000000))
198: (77) r6 >>= 32
R6=inv(id=0,umax_value=0xffffffff,var_off=(0x0; 0xffffffff))
...
201: (79) r8 = *(u64 *)(r10 -416)
R8_w=map_value(id=0,off=40,ks=4,vs=13872,imm=0)
202: (0f) r8 += r6
R8_w=map_value(id=0,off=40,ks=4,vs=13872,umax_value=0xffffffff,var_off=(0x0; 0xffffffff))
203: (07) r8 += 9696
R8_w=map_value(id=0,off=9736,ks=4,vs=13872,umax_value=0xffffffff,var_off=(0x0; 0xffffffff))
...
255: (bf) r1 = r8
R1_w=map_value(id=0,off=9736,ks=4,vs=13872,umax_value=0xffffffff,var_off=(0x0; 0xffffffff))
...
257: (85) call bpf_probe_read_user_str#114
R1 unbounded memory access, make sure to bounds check any array access into a map
The value range for register r6 at insn 198 should be really just 0/1.
The umax_value=0xffffffff caused later verification failure.
After jmp instructions, the current verifier already tried to use just
obtained information to get better register range. The current mechanism is
for 64bit register only. This patch implemented to tighten the range
for 32bit sub-registers after jmp32 instructions.
With the patch, we have the below range ranges for the
above code sequence:
193: (85) call bpf_probe_read_user_str#114
R0=inv(id=0)
194: (26) if w0 > 0x1 goto pc+4
R0_w=inv(id=0,smax_value=0x7fffffff00000001,umax_value=0xffffffff00000001,
var_off=(0x0; 0xffffffff00000001))
195: (6b) *(u16 *)(r7 +80) = r0
196: (bc) w6 = w0
R6_w=inv(id=0,umax_value=0xffffffff,var_off=(0x0; 0x1))
197: (67) r6 <<= 32
R6_w=inv(id=0,umax_value=0x100000000,var_off=(0x0; 0x100000000))
198: (77) r6 >>= 32
R6=inv(id=0,umax_value=1,var_off=(0x0; 0x1))
...
201: (79) r8 = *(u64 *)(r10 -416)
R8_w=map_value(id=0,off=40,ks=4,vs=13872,imm=0)
202: (0f) r8 += r6
R8_w=map_value(id=0,off=40,ks=4,vs=13872,umax_value=1,var_off=(0x0; 0x1))
203: (07) r8 += 9696
R8_w=map_value(id=0,off=9736,ks=4,vs=13872,umax_value=1,var_off=(0x0; 0x1))
...
255: (bf) r1 = r8
R1_w=map_value(id=0,off=9736,ks=4,vs=13872,umax_value=1,var_off=(0x0; 0x1))
...
257: (85) call bpf_probe_read_user_str#114
...
At insn 194, the register R0 has better var_off.mask and smax_value.
Especially, the var_off.mask ensures later lshift and rshift
maintains proper value range.
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191121170650.449030-1-yhs@fb.com
Tetsuo pointed out that it was not only the device unregister hook that was
broken for devmap_hash types, it was also cleanup on map free. So better
fix this as well.
While we're at it, there's no reason to allocate the netdev_map array for
DEVMAP_HASH, so skip that and adjust the cost accordingly.
Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20191121133612.430414-1-toke@redhat.com
Only the function calls are stubbed out with static inlines that always
fail. This is the standard way to write a header for an optional component
and makes it easier for drivers that only optionally need HMM_MIRROR.
Link: https://lore.kernel.org/r/20191112202231.3856-5-jgg@ziepe.ca
Reviewed-by: Jérôme Glisse <jglisse@redhat.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This commit reverts commit 91e6015b08 ("bpf: Emit audit messages
upon successful prog load and unload") and its follow up commit
7599a896f2 ("audit: Move audit_log_task declaration under
CONFIG_AUDITSYSCALL") as requested by Paul Moore. The change needs
close review on linux-audit, tests etc.
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Currently, a lot of memory is wasted for architectures like MIPS when
init_ftrace_syscalls() allocates the array for syscalls using kcalloc.
This is because syscalls numbers start from 4000, 5000 or 6000 and
array elements up to that point are unused.
Fix this by using a data structure more suited to storing sparsely
populated arrays. The XARRAY data structure, implemented using radix
trees, is much more memory efficient for storing the syscalls in
question.
Link: http://lkml.kernel.org/r/20191115234314.21599-1-hnaveed@wavecomp.com
Signed-off-by: Hassan Naveed <hnaveed@wavecomp.com>
Reviewed-by: Paul Burton <paulburton@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adding 2 new functions -
1) struct trace_array *trace_array_get_by_name(const char *name);
Return pointer to a trace array with given name. If it does not exist,
create and return pointer to the new trace array.
2) int trace_array_set_clr_event(struct trace_array *tr,
const char *system ,const char *event, bool enable);
Enable/Disable events to this trace array.
Additionally,
- To handle reference counters, export trace_array_put()
- Due to introduction of the above 2 new functions, we no longer need to
export - ftrace_set_clr_event & trace_array_create APIs.
Link: http://lkml.kernel.org/r/1574276919-11119-2-git-send-email-divya.indi@oracle.com
Signed-off-by: Divya Indi <divya.indi@oracle.com>
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Adjust indentation from spaces to tab (+optional two spaces) as in
coding style with command like:
$ sed -e 's/^ /\t/' -i */Kconfig
Link: http://lkml.kernel.org/r/20191120133807.12741-1-krzk@kernel.org
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Minor conflict in drivers/s390/net/qeth_l2_main.c, kept the lock
from commit c8183f5489 ("s390/qeth: fix potential deadlock on
workqueue flush"), removed the code which was removed by commit
9897d583b0 ("s390/qeth: consolidate some duplicated HW cmd code").
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Pull networking fixes from David Miller:
1) Validate tunnel options length in act_tunnel_key, from Xin Long.
2) Fix DMA sync bug in gve driver, from Adi Suresh.
3) TSO kills performance on some r8169 chips due to HW issues, disable
by default in that case, from Corinna Vinschen.
4) Fix clock disable mismatch in fec driver, from Chubong Yuan.
5) Fix interrupt status bits define in hns3 driver, from Huazhong Tan.
6) Fix workqueue deadlocks in qeth driver, from Julian Wiedmann.
7) Don't napi_disable() twice in r8152 driver, from Hayes Wang.
8) Fix SKB extension memory leak, from Florian Westphal.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (54 commits)
r8152: avoid to call napi_disable twice
MAINTAINERS: Add myself as maintainer of virtio-vsock
udp: drop skb extensions before marking skb stateless
net: rtnetlink: prevent underflows in do_setvfinfo()
can: m_can_platform: remove unnecessary m_can_class_resume() call
can: m_can_platform: set net_device structure as driver data
hv_netvsc: Fix send_table offset in case of a host bug
hv_netvsc: Fix offset usage in netvsc_send_table()
net-ipv6: IPV6_TRANSPARENT - check NET_RAW prior to NET_ADMIN
sfc: Only cancel the PPS workqueue if it exists
nfc: port100: handle command failure cleanly
net-sysfs: fix netdev_queue_add_kobject() breakage
r8152: Re-order napi_disable in rtl8152_close
net: qca_spi: Move reset_count to struct qcaspi
net: qca_spi: fix receive buffer size check
net/ibmvnic: Ignore H_FUNCTION return from H_EOI to tolerate XIVE mode
Revert "net/ibmvnic: Fix EOI when running in XIVE mode"
net/mlxfw: Verify FSM error code translation doesn't exceed array size
net/mlx5: Update the list of the PCI supported devices
net/mlx5: Fix auto group size calculation
...
Fix problems with switching cpufreq drivers on some x86 systems with
ACPI (and with changing the operation modes of the intel_pstate driver
on those systems) introduced by recent changes related to the
management of frequency limits in cpufreq.
-----BEGIN PGP SIGNATURE-----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=S23p
-----END PGP SIGNATURE-----
Merge tag 'pm-5.4-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management regression fix from Rafael Wysocki:
"Fix problems with switching cpufreq drivers on some x86 systems with
ACPI (and with changing the operation modes of the intel_pstate driver
on those systems) introduced by recent changes related to the
management of frequency limits in cpufreq"
* tag 'pm-5.4-final' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PM: QoS: Invalidate frequency QoS requests after removal
Using a mask to represent bus DMA constraints has a set of limitations.
The biggest one being it can only hold a power of two (minus one). The
DMA mapping code is already aware of this and treats dev->bus_dma_mask
as a limit. This quirk is already used by some architectures although
still rare.
With the introduction of the Raspberry Pi 4 we've found a new contender
for the use of bus DMA limits, as its PCIe bus can only address the
lower 3GB of memory (of a total of 4GB). This is impossible to represent
with a mask. To make things worse the device-tree code rounds non power
of two bus DMA limits to the next power of two, which is unacceptable in
this case.
In the light of this, rename dev->bus_dma_mask to dev->bus_dma_limit all
over the tree and treat it as such. Note that dev->bus_dma_limit should
contain the higher accessible DMA address.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Commit:
d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
does a lot of things to the mlock accounting arithmetics, while the only
thing that actually needed to happen is subtracting the part that is
charged to the mm from the part that is charged to the user, so that the
former isn't charged twice.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Cc: songliubraving@fb.com
Link: https://lkml.kernel.org/r/20191120170640.54123-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Many callsites want to fetch the values of system, user, user_nice, guest
or guest_nice kcpustat fields altogether or at least a pair of these.
In that case calling kcpustat_field() for each requested field brings
unecessary overhead when we could fetch all of them in a row.
So provide kcpustat_cpu_fetch() that fetches the whole kcpustat array
in a vtime safe way under the same RCU and seqcount block.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191121024430.19938-3-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Provide support for user, nice, guest and guest_nice fields through
kcpustat_field().
Whether we account the delta to a nice or not nice field is decided on
top of the nice value snapshot taken at the time we call kcpustat_field().
If the nice value of the task has been changed since the last vtime
update, we may have inacurrate distribution of the nice VS unnice
cputime.
However this is considered as a minor issue compared to the proper fix
that would involve interrupting the target on nice updates, which is
undesired on nohz_full CPUs.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191121024430.19938-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-11-20
The following pull-request contains BPF updates for your *net-next* tree.
We've added 81 non-merge commits during the last 17 day(s) which contain
a total of 120 files changed, 4958 insertions(+), 1081 deletions(-).
There are 3 trivial conflicts, resolve it by always taking the chunk from
196e8ca748:
<<<<<<< HEAD
=======
void *bpf_map_area_mmapable_alloc(u64 size, int numa_node);
>>>>>>> 196e8ca748
<<<<<<< HEAD
void *bpf_map_area_alloc(u64 size, int numa_node)
=======
static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
>>>>>>> 196e8ca748
<<<<<<< HEAD
if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
=======
/* kmalloc()'ed memory can't be mmap()'ed */
if (!mmapable && size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
>>>>>>> 196e8ca748
The main changes are:
1) Addition of BPF trampoline which works as a bridge between kernel functions,
BPF programs and other BPF programs along with two new use cases: i) fentry/fexit
BPF programs for tracing with practically zero overhead to call into BPF (as
opposed to k[ret]probes) and ii) attachment of the former to networking related
programs to see input/output of networking programs (covering xdpdump use case),
from Alexei Starovoitov.
2) BPF array map mmap support and use in libbpf for global data maps; also a big
batch of libbpf improvements, among others, support for reading bitfields in a
relocatable manner (via libbpf's CO-RE helper API), from Andrii Nakryiko.
3) Extend s390x JIT with usage of relative long jumps and loads in order to lift
the current 64/512k size limits on JITed BPF programs there, from Ilya Leoshkevich.
4) Add BPF audit support and emit messages upon successful prog load and unload in
order to have a timeline of events, from Daniel Borkmann and Jiri Olsa.
5) Extension to libbpf and xdpsock sample programs to demo the shared umem mode
(XDP_SHARED_UMEM) as well as RX-only and TX-only sockets, from Magnus Karlsson.
6) Several follow-up bug fixes for libbpf's auto-pinning code and a new API
call named bpf_get_link_xdp_info() for retrieving the full set of prog
IDs attached to XDP, from Toke Høiland-Jørgensen.
7) Add BTF support for array of int, array of struct and multidimensional arrays
and enable it for skb->cb[] access in kfree_skb test, from Martin KaFai Lau.
8) Fix AF_XDP by using the correct number of channels from ethtool, from Luigi Rizzo.
9) Two fixes for BPF selftest to get rid of a hang in test_tc_tunnel and to avoid
xdping to be run as standalone, from Jiri Benc.
10) Various BPF selftest fixes when run with latest LLVM trunk, from Yonghong Song.
11) Fix a memory leak in BPF fentry test run data, from Colin Ian King.
12) Various smaller misc cleanups and improvements mostly all over BPF selftests and
samples, from Daniel T. Lee, Andre Guedes, Anders Roxell, Mao Wenan, Yue Haibing.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
On compat interfaces, the high order bits of nanoseconds should be zeroed
out. This is because the application code or the libc do not guarantee
zeroing of these. If used without zeroing, kernel might be at risk of using
timespec values incorrectly.
Originally it was handled correctly, but lost during is_compat_syscall()
cleanup. Revert the condition back to check CONFIG_64BIT.
Fixes: 98f76206b3 ("compat: Cleanup in_compat_syscall() callers")
Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Dmitry Safonov <dima@arista.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20191121000303.126523-1-dima@arista.com
Given we recently extended the original bpf_map_area_alloc() helper in
commit fc9702273e ("bpf: Add mmap() support for BPF_MAP_TYPE_ARRAY"),
we need to apply the same logic as in ff1c08e1f7 ("bpf: Change size
to u64 for bpf_map_{area_alloc, charge_init}()"). To avoid conflicts,
extend it for bpf-next.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Allow for audit messages to be emitted upon BPF program load and
unload for having a timeline of events. The load itself is in
syscall context, so additional info about the process initiating
the BPF prog creation can be logged and later directly correlated
to the unload event.
The only info really needed from BPF side is the globally unique
prog ID where then audit user space tooling can query / dump all
info needed about the specific BPF program right upon load event
and enrich the record, thus these changes needed here can be kept
small and non-intrusive to the core.
Raw example output:
# auditctl -D
# auditctl -a always,exit -F arch=x86_64 -S bpf
# ausearch --start recent -m 1334
[...]
----
time->Wed Nov 20 12:45:51 2019
type=PROCTITLE msg=audit(1574271951.590:8974): proctitle="./test_verifier"
type=SYSCALL msg=audit(1574271951.590:8974): arch=c000003e syscall=321 success=yes exit=14 a0=5 a1=7ffe2d923e80 a2=78 a3=0 items=0 ppid=742 pid=949 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=0 fsgid=0 tty=pts0 ses=2 comm="test_verifier" exe="/root/bpf-next/tools/testing/selftests/bpf/test_verifier" subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 key=(null)
type=UNKNOWN[1334] msg=audit(1574271951.590:8974): auid=0 uid=0 gid=0 ses=2 subj=unconfined_u:unconfined_r:unconfined_t:s0-s0:c0.c1023 pid=949 comm="test_verifier" exe="/root/bpf-next/tools/testing/selftests/bpf/test_verifier" prog-id=3260 event=LOAD
----
time->Wed Nov 20 12:45:51 2019
type=UNKNOWN[1334] msg=audit(1574271951.590:8975): prog-id=3260 event=UNLOAD
----
[...]
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191120213816.8186-1-jolsa@kernel.org
The valid memory address check in dma_capable only makes sense when mapping
normal memory, not when using dma_map_resource to map a device resource.
Add a new boolean argument to dma_capable to exclude that check for the
dma_map_resource case.
Fixes: b12d66278d ("dma-direct: check for overflows on 32 bit DMA addresses")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
When mapping resources we can't just use swiotlb ram for bounce
buffering. Switch to a direct dma_capable check instead.
Fixes: cfced78696 ("dma-mapping: remove the default map_resource implementation")
Reported-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
The put_hash_bucket() is a bit cleaner if it takes an unsigned long
directly instead of a pointer to unsigned long.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
These are pure cache maintainance routines, so drop the unused
struct device argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch>
pidfd_poll() is defined as returning 'unsigned int' but the
.poll method is declared as returning '__poll_t', a bitwise type.
Fix this by using the proper return type and using the EPOLL
constants instead of the POLL ones, as required for __poll_t.
Fixes: b53b0b9d9a ("pidfd: add polling support")
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: stable@vger.kernel.org # 5.3
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20191120003320.31138-1-luc.vanoostenryck@gmail.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Modify cpuidle_use_deepest_state() to take an additional exit latency
limit argument to be passed to find_deepest_idle_state() and make
cpuidle_idle_call() pass dev->forced_idle_latency_limit_ns to it for
forced idle.
Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
[ rjw: Rebase and rearrange code, subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In some cases it may be useful to specify an exit latency limit for
the idle state to be used during CPU idle time injection.
Instead of duplicating the information in struct cpuidle_device
or propagating the latency limit in the call stack, replace the
use_deepest_state field with forced_latency_limit_ns to represent
that limit, so that the deepest idle state with exit latency within
that limit is forced (i.e. no governors) when it is set.
A zero exit latency limit for forced idle means to use governors in
the usual way (analogous to use_deepest_state equal to "false" before
this change).
Additionally, add play_idle_precise() taking two arguments, the
duration of forced idle and the idle state exit latency limit, both
in nanoseconds, and redefine play_idle() as a wrapper around that
new function.
This change is preparatory, no functional impact is expected.
Suggested-by: Rafael J. Wysocki <rafael@kernel.org>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
[ rjw: Subject, changelog, cpuidle_use_deepest_state() kerneldoc, whitespace ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tidy up a few bits:
- Fix typos and grammar, improve wording.
- Remove spurious newlines that are col80 warning artifacts where the
resulting line-break is worse than the disease it's curing.
- Use core kernel coding style to improve readability and reduce
spurious code pattern variations.
- Use better vertical alignment for structure definitions and initialization
sequences.
- Misc other small details.
No change in functionality intended.
Cc: linux-kernel@vger.kernel.org
Cc: Marco Elver <elver@google.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Switching cpufreq drivers (or switching operation modes of the
intel_pstate driver from "active" to "passive" and vice versa)
does not work on some x86 systems with ACPI after commit
3000ce3c52 ("cpufreq: Use per-policy frequency QoS"), because
the ACPI _PPC and thermal code uses the same frequency QoS request
object for a given CPU every time a cpufreq driver is registered
and freq_qos_remove_request() does not invalidate the request after
removing it from its QoS list, so freq_qos_add_request() complains
and fails when that request is passed to it again.
Fix the issue by modifying freq_qos_remove_request() to clear the qos
and type fields of the frequency request pointed to by its argument
after removing it from its QoS list so as to invalidate it.
Fixes: 3000ce3c52 ("cpufreq: Use per-policy frequency QoS")
Reported-and-tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Oleg provided the following test case:
int main(void)
{
struct sched_param sp = {};
sp.sched_priority = 2;
assert(sched_setscheduler(0, SCHED_FIFO, &sp) == 0);
int lock = vfork();
if (!lock) {
sp.sched_priority = 1;
assert(sched_setscheduler(0, SCHED_FIFO, &sp) == 0);
_exit(0);
}
syscall(__NR_futex, &lock, FUTEX_LOCK_PI, 0,0,0);
return 0;
}
This creates an unkillable RT process spinning in futex_lock_pi() on a UP
machine or if the process is affine to a single CPU. The reason is:
parent child
set FIFO prio 2
vfork() -> set FIFO prio 1
implies wait_for_child() sched_setscheduler(...)
exit()
do_exit()
....
mm_release()
tsk->futex_state = FUTEX_STATE_EXITING;
exit_futex(); (NOOP in this case)
complete() --> wakes parent
sys_futex()
loop infinite because
tsk->futex_state == FUTEX_STATE_EXITING
The same problem can happen just by regular preemption as well:
task holds futex
...
do_exit()
tsk->futex_state = FUTEX_STATE_EXITING;
--> preemption (unrelated wakeup of some other higher prio task, e.g. timer)
switch_to(other_task)
return to user
sys_futex()
loop infinite as above
Just for the fun of it the futex exit cleanup could trigger the wakeup
itself before the task sets its futex state to DEAD.
To cure this, the handling of the exiting owner is changed so:
- A refcount is held on the task
- The task pointer is stored in a caller visible location
- The caller drops all locks (hash bucket, mmap_sem) and blocks
on task::futex_exit_mutex. When the mutex is acquired then
the exiting task has completed the cleanup and the state
is consistent and can be reevaluated.
This is not a pretty solution, but there is no choice other than returning
an error code to user space, which would break the state consistency
guarantee and open another can of problems including regressions.
For stable backports the preparatory commits ac31c7ff86 .. ba31c1a485
are required as well, but for anything older than 5.3.y the backports are
going to be provided when this hits mainline as the other dependencies for
those kernels are definitely not stable material.
Fixes: 778e9a9c3e ("pi-futex: fix exit races and locking problems")
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stable Team <stable@vger.kernel.org>
Link: https://lkml.kernel.org/r/20191106224557.041676471@linutronix.de
attach_to_pi_owner() returns -EAGAIN for various cases:
- Owner task is exiting
- Futex value has changed
The caller drops the held locks (hash bucket, mmap_sem) and retries the
operation. In case of the owner task exiting this can result in a live
lock.
As a preparatory step for seperating those cases, provide a distinct return
value (EBUSY) for the owner exiting case.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.935606117@linutronix.de
The mutex will be used in subsequent changes to replace the busy looping of
a waiter when the futex owner is currently executing the exit cleanup to
prevent a potential live lock.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.845798895@linutronix.de
exec() attempts to handle potentially held futexes gracefully by running
the futex exit handling code like exit() does.
The current implementation has no protection against concurrent incoming
waiters. The reason is that the futex state cannot be set to
FUTEX_STATE_DEAD after the cleanup because the task struct is still active
and just about to execute the new binary.
While its arguably buggy when a task holds a futex over exec(), for
consistency sake the state handling can at least cover the actual futex
exit cleanup section. This provides state consistency protection accross
the cleanup. As the futex state of the task becomes FUTEX_STATE_OK after the
cleanup has been finished, this cannot prevent subsequent attempts to
attach to the task in case that the cleanup was not successfull in mopping
up all leftovers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.753355618@linutronix.de
Instead of having a smp_mb() and an empty lock/unlock of task::pi_lock move
the state setting into to the lock section.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.645603214@linutronix.de
Instead of relying on PF_EXITING use an explicit state for the futex exit
and set it in the futex exit function. This moves the smp barrier and the
lock/unlock serialization into the futex code.
As with the DEAD state this is restricted to the exit path as exec
continues to use the same task struct.
This allows to simplify that logic in a next step.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.539409004@linutronix.de
Setting task::futex_state in do_exit() is rather arbitrarily placed for no
reason. Move it into the futex code.
Note, this is only done for the exit cleanup as the exec cleanup cannot set
the state to FUTEX_STATE_DEAD because the task struct is still in active
use.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.439511191@linutronix.de
To allow separate handling of the futex exit state in the futex exit code
for exit and exec, split futex_mm_release() into two functions and invoke
them from the corresponding exit/exec_mm_release() callsites.
Preparatory only, no functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.332094221@linutronix.de
mm_release() contains the futex exit handling. mm_release() is called from
do_exit()->exit_mm() and from exec()->exec_mm().
In the exit_mm() case PF_EXITING and the futex state is updated. In the
exec_mm() case these states are not touched.
As the futex exit code needs further protections against exit races, this
needs to be split into two functions.
Preparatory only, no functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.240518241@linutronix.de
The futex exit handling relies on PF_ flags. That's suboptimal as it
requires a smp_mb() and an ugly lock/unlock of the exiting tasks pi_lock in
the middle of do_exit() to enforce the observability of PF_EXITING in the
futex code.
Add a futex_state member to task_struct and convert the PF_EXITPIDONE logic
over to the new state. The PF_EXITING dependency will be cleaned up in a
later step.
This prepares for handling various futex exit issues later.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.149449274@linutronix.de
The futex exit handling is #ifdeffed into mm_release() which is not pretty
to begin with. But upcoming changes to address futex exit races need to add
more functionality to this exit code.
Split it out into a function, move it into futex code and make the various
futex exit functions static.
Preparatory only and no functional change.
Folded build fix from Borislav.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20191106224556.049705556@linutronix.de
Fix sparse warning:
kernel/bpf/arraymap.c:481:5: warning:
symbol 'array_map_mmap' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191119142113.15388-1-yuehaibing@huawei.com
The ftrace_graph_stub was created and points to ftrace_stub as a way to
assign the functon graph tracer function pointer to a stub function with a
different prototype than what ftrace_stub has and not trigger the C
verifier. The ftrace_graph_stub was created via the linker script
vmlinux.lds.h. Unfortunately, powerpc already uses the name
ftrace_graph_stub for its internal implementation of the function graph
tracer, and even though powerpc would still build, the change via the linker
script broke function tracer on powerpc from working.
By using the name ftrace_stub_graph, which does not exist anywhere else in
the kernel, this should not be a problem.
Link: https://lore.kernel.org/r/1573849732.5937.136.camel@lca.pw
Fixes: b83b43ffc6 ("fgraph: Fix function type mismatches of ftrace_graph_return using ftrace_stub")
Reorted-by: Qian Cai <cai@lca.pw>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If a direct ftrace callback is at a location that does not have any other
ftrace helpers attached to it, it is possible to simply just change the
text to call the new caller (if the architecture supports it). But this
requires special architecture code. Currently, modify_ftrace_direct() uses a
trick to add a stub ftrace callback to the location forcing it to call the
ftrace iterator. Then it can change the direct helper to call the new
function in C, and then remove the stub. Removing the stub will have the
location now call the new location that the direct helper is using.
The new helper function does the registering the stub trick, but is a weak
function, allowing an architecture to override it to do something a bit more
direct.
Link: https://lore.kernel.org/r/20191115215125.mbqv7taqnx376yed@ast-mbp.dhcp.thefacebook.com
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Commit:
5e6c3c7b1e ("perf/aux: Fix tracking of auxiliary trace buffer allocation")
tried to guess the correct combination of arithmetic operations that would
undo the AUX buffer's mlock accounting, and failed, leaking the bottom part
when an allocation needs to be charged partially to both user->locked_vm
and mm->pinned_vm, eventually leaving the user with no locked bonus:
$ perf record -e intel_pt//u -m1,128 uname
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.061 MB perf.data ]
$ perf record -e intel_pt//u -m1,128 uname
Permission error mapping pages.
Consider increasing /proc/sys/kernel/perf_event_mlock_kb,
or try again with a smaller value of -m/--mmap_pages.
(current value: 1,128)
Fix this by subtracting both locked and pinned counts when AUX buffer is
unmapped.
Reported-by: Thomas Richter <tmricht@linux.ibm.com>
Tested-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
update_cfs_rq_load_avg() calls cfs_rq_util_change() every time PELT decays,
which might be inefficient when the cpufreq driver has rate limitation.
When a task is attached on a CPU, we have this call path:
update_load_avg()
update_cfs_rq_load_avg()
cfs_rq_util_change -- > trig frequency update
attach_entity_load_avg()
cfs_rq_util_change -- > trig frequency update
The 1st frequency update will not take into account the utilization of the
newly attached task and the 2nd one might be discarded because of rate
limitation of the cpufreq driver.
update_cfs_rq_load_avg() is only called by update_blocked_averages()
and update_load_avg() so we can move the call to
cfs_rq_util_change/cpufreq_update_util() into these two functions.
It's also interesting to note that update_load_avg() already calls
cfs_rq_util_change() directly for the !SMP case.
This change will also ensure that cpufreq_update_util() is called even
when there is no more CFS rq in the leaf_cfs_rq_list to update, but only
IRQ, RT or DL PELT signals.
[ mingo: Minor updates. ]
Reported-by: Doug Smythies <dsmythies@telus.net>
Tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: juri.lelli@redhat.com
Cc: linux-pm@vger.kernel.org
Cc: mgorman@suse.de
Cc: rostedt@goodmis.org
Cc: sargun@sargun.me
Cc: srinivas.pandruvada@linux.intel.com
Cc: tj@kernel.org
Cc: xiexiuqi@huawei.com
Cc: xiezhipeng1@huawei.com
Fixes: 039ae8bcf7 ("sched/fair: Fix O(nr_cgroups) in the load balancing path")
Link: https://lkml.kernel.org/r/1574083279-799-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add comments to describe each state of goup_type and to add some details
about the load balance at NUMA level.
[ Valentin Schneider: Updates to the comments. ]
[ mingo: Other updates to the comments. ]
Reported-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Valentin Schneider <valentin.schneider@arm.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1573570243-1903-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The task, for which the scheduler looks for the idlest group of CPUs, must
be discounted from all statistics in order to get a fair comparison
between groups. This includes utilization, load, nr_running and idle_cpus.
Such unfairness can be easily highlighted with the unixbench execl 1 task.
This test continuously call execve() and the scheduler looks for the idlest
group/CPU on which it should place the task. Because the task runs on the
local group/CPU, the latter seems already busy even if there is nothing
else running on it. As a result, the scheduler will always select another
group/CPU than the local one.
This recovers most of the performance regression on my system from the
recent load-balancer rewrite.
[ mingo: Minor cleanups. ]
Reported-by: kernel test robot <rong.a.chen@intel.com>
Tested-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Fixes: 57abff067a ("sched/fair: Rework find_idlest_group()")
Link: https://lkml.kernel.org/r/1571762798-25900-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add ability to memory-map contents of BPF array map. This is extremely useful
for working with BPF global data from userspace programs. It allows to avoid
typical bpf_map_{lookup,update}_elem operations, improving both performance
and usability.
There had to be special considerations for map freezing, to avoid having
writable memory view into a frozen map. To solve this issue, map freezing and
mmap-ing is happening under mutex now:
- if map is already frozen, no writable mapping is allowed;
- if map has writable memory mappings active (accounted in map->writecnt),
map freezing will keep failing with -EBUSY;
- once number of writable memory mappings drops to zero, map freezing can be
performed again.
Only non-per-CPU plain arrays are supported right now. Maps with spinlocks
can't be memory mapped either.
For BPF_F_MMAPABLE array, memory allocation has to be done through vmalloc()
to be mmap()'able. We also need to make sure that array data memory is
page-sized and page-aligned, so we over-allocate memory in such a way that
struct bpf_array is at the end of a single page of memory with array->value
being aligned with the start of the second page. On deallocation we need to
accomodate this memory arrangement to free vmalloc()'ed memory correctly.
One important consideration regarding how memory-mapping subsystem functions.
Memory-mapping subsystem provides few optional callbacks, among them open()
and close(). close() is called for each memory region that is unmapped, so
that users can decrease their reference counters and free up resources, if
necessary. open() is *almost* symmetrical: it's called for each memory region
that is being mapped, **except** the very first one. So bpf_map_mmap does
initial refcnt bump, while open() will do any extra ones after that. Thus
number of close() calls is equal to number of open() calls plus one more.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-4-andriin@fb.com
Similarly to bpf_map's refcnt/usercnt, convert bpf_prog's refcnt to atomic64
and remove artificial 32k limit. This allows to make bpf_prog's refcounting
non-failing, simplifying logic of users of bpf_prog_add/bpf_prog_inc.
Validated compilation by running allyesconfig kernel build.
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-3-andriin@fb.com
92117d8443 ("bpf: fix refcnt overflow") turned refcounting of bpf_map into
potentially failing operation, when refcount reaches BPF_MAX_REFCNT limit
(32k). Due to using 32-bit counter, it's possible in practice to overflow
refcounter and make it wrap around to 0, causing erroneous map free, while
there are still references to it, causing use-after-free problems.
But having a failing refcounting operations are problematic in some cases. One
example is mmap() interface. After establishing initial memory-mapping, user
is allowed to arbitrarily map/remap/unmap parts of mapped memory, arbitrarily
splitting it into multiple non-contiguous regions. All this happening without
any control from the users of mmap subsystem. Rather mmap subsystem sends
notifications to original creator of memory mapping through open/close
callbacks, which are optionally specified during initial memory mapping
creation. These callbacks are used to maintain accurate refcount for bpf_map
(see next patch in this series). The problem is that open() callback is not
supposed to fail, because memory-mapped resource is set up and properly
referenced. This is posing a problem for using memory-mapping with BPF maps.
One solution to this is to maintain separate refcount for just memory-mappings
and do single bpf_map_inc/bpf_map_put when it goes from/to zero, respectively.
There are similar use cases in current work on tcp-bpf, necessitating extra
counter as well. This seems like a rather unfortunate and ugly solution that
doesn't scale well to various new use cases.
Another approach to solve this is to use non-failing refcount_t type, which
uses 32-bit counter internally, but, once reaching overflow state at UINT_MAX,
stays there. This utlimately causes memory leak, but prevents use after free.
But given refcounting is not the most performance-critical operation with BPF
maps (it's not used from running BPF program code), we can also just switch to
64-bit counter that can't overflow in practice, potentially disadvantaging
32-bit platforms a tiny bit. This simplifies semantics and allows above
described scenarios to not worry about failing refcount increment operation.
In terms of struct bpf_map size, we are still good and use the same amount of
space:
BEFORE (3 cache lines, 8 bytes of padding at the end):
struct bpf_map {
const struct bpf_map_ops * ops __attribute__((__aligned__(64))); /* 0 8 */
struct bpf_map * inner_map_meta; /* 8 8 */
void * security; /* 16 8 */
enum bpf_map_type map_type; /* 24 4 */
u32 key_size; /* 28 4 */
u32 value_size; /* 32 4 */
u32 max_entries; /* 36 4 */
u32 map_flags; /* 40 4 */
int spin_lock_off; /* 44 4 */
u32 id; /* 48 4 */
int numa_node; /* 52 4 */
u32 btf_key_type_id; /* 56 4 */
u32 btf_value_type_id; /* 60 4 */
/* --- cacheline 1 boundary (64 bytes) --- */
struct btf * btf; /* 64 8 */
struct bpf_map_memory memory; /* 72 16 */
bool unpriv_array; /* 88 1 */
bool frozen; /* 89 1 */
/* XXX 38 bytes hole, try to pack */
/* --- cacheline 2 boundary (128 bytes) --- */
atomic_t refcnt __attribute__((__aligned__(64))); /* 128 4 */
atomic_t usercnt; /* 132 4 */
struct work_struct work; /* 136 32 */
char name[16]; /* 168 16 */
/* size: 192, cachelines: 3, members: 21 */
/* sum members: 146, holes: 1, sum holes: 38 */
/* padding: 8 */
/* forced alignments: 2, forced holes: 1, sum forced holes: 38 */
} __attribute__((__aligned__(64)));
AFTER (same 3 cache lines, no extra padding now):
struct bpf_map {
const struct bpf_map_ops * ops __attribute__((__aligned__(64))); /* 0 8 */
struct bpf_map * inner_map_meta; /* 8 8 */
void * security; /* 16 8 */
enum bpf_map_type map_type; /* 24 4 */
u32 key_size; /* 28 4 */
u32 value_size; /* 32 4 */
u32 max_entries; /* 36 4 */
u32 map_flags; /* 40 4 */
int spin_lock_off; /* 44 4 */
u32 id; /* 48 4 */
int numa_node; /* 52 4 */
u32 btf_key_type_id; /* 56 4 */
u32 btf_value_type_id; /* 60 4 */
/* --- cacheline 1 boundary (64 bytes) --- */
struct btf * btf; /* 64 8 */
struct bpf_map_memory memory; /* 72 16 */
bool unpriv_array; /* 88 1 */
bool frozen; /* 89 1 */
/* XXX 38 bytes hole, try to pack */
/* --- cacheline 2 boundary (128 bytes) --- */
atomic64_t refcnt __attribute__((__aligned__(64))); /* 128 8 */
atomic64_t usercnt; /* 136 8 */
struct work_struct work; /* 144 32 */
char name[16]; /* 176 16 */
/* size: 192, cachelines: 3, members: 21 */
/* sum members: 154, holes: 1, sum holes: 38 */
/* forced alignments: 2, forced holes: 1, sum forced holes: 38 */
} __attribute__((__aligned__(64)));
This patch, while modifying all users of bpf_map_inc, also cleans up its
interface to match bpf_map_put with separate operations for bpf_map_inc and
bpf_map_inc_with_uref (to match bpf_map_put and bpf_map_put_with_uref,
respectively). Also, given there are no users of bpf_map_inc_not_zero
specifying uref=true, remove uref flag and default to uref=false internally.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191117172806.2195367-2-andriin@fb.com
Daniel Borkmann says:
====================
pull-request: bpf 2019-11-15
The following pull-request contains BPF updates for your *net* tree.
We've added 1 non-merge commits during the last 9 day(s) which contain
a total of 1 file changed, 3 insertions(+), 1 deletion(-).
The main changes are:
1) Fix a missing unlock of bpf_devs_lock in bpf_offload_dev_create()'s
error path, from Dan.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Some uclamp helpers had their return type changed from 'unsigned int' to
'enum uclamp_id' by commit
0413d7f33e ("sched/uclamp: Always use 'enum uclamp_id' for clamp_id values")
but it happens that some do return a value in the [0, SCHED_CAPACITY_SCALE]
range, which should really be unsigned int. The affected helpers are
uclamp_none(), uclamp_rq_max_value() and uclamp_eff_value(). Fix those up.
Note that this doesn't lead to any obj diff using a relatively recent
aarch64 compiler (8.3-2019.03). The current code of e.g. uclamp_eff_value()
properly returns an 11 bit value (bits_per(1024)) and doesn't seem to do
anything funny. I'm still marking this as fixing the above commit to be on
the safe side.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Qais Yousef <qais.yousef@arm.com>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar.Eggemann@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: patrick.bellasi@matbug.net
Cc: qperret@google.com
Cc: surenb@google.com
Cc: tj@kernel.org
Fixes: 0413d7f33e ("sched/uclamp: Always use 'enum uclamp_id' for clamp_id values")
Link: https://lkml.kernel.org/r/20191115103908.27610-1-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf fixes from Ingo Molnar:
"Misc fixes: a handful of AUX event handling related fixes, a Sparse
fix and two ABI fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/core: Fix missing static inline on perf_cgroup_switch()
perf/core: Consistently fail fork on allocation failures
perf/aux: Disallow aux_output for kernel events
perf/core: Reattach a misplaced comment
perf/aux: Fix the aux_output group inheritance fix
perf/core: Disallow uncore-cgroup events
This blacklists several compilation units from KCSAN. See the respective
inline comments for the reasoning.
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Kernel Concurrency Sanitizer (KCSAN) is a dynamic data-race detector for
kernel space. KCSAN is a sampling watchpoint-based data-race detector.
See the included Documentation/dev-tools/kcsan.rst for more details.
This patch adds basic infrastructure, but does not yet enable KCSAN for
any architecture.
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
On certain QTI chipsets some GPIOs are direct-connect interrupts to the
GIC to be used as regular interrupt lines. When the GPIOs are not used
for interrupt generation the interrupt line is disabled. But disabling
the interrupt at GIC does not prevent the interrupt to be reported as
pending at GIC_ISPEND. Later, when drivers call enable_irq() on the
interrupt, an unwanted interrupt occurs.
Introduce get and set methods for irqchip's parent to clear it's pending
irq state. This then can be invoked by the GPIO interrupt controller on
the parents in it hierarchy to clear the interrupt before enabling the
interrupt.
Signed-off-by: Maulik Shah <mkshah@codeaurora.org>
Signed-off-by: Lina Iyer <ilina@codeaurora.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/1573855915-9841-7-git-send-email-ilina@codeaurora.org
[updated commit text and minor code fixes]
The main motivation to add set_tid to clone3() is CRIU.
To restore a process with the same PID/TID CRIU currently uses
/proc/sys/kernel/ns_last_pid. It writes the desired (PID - 1) to
ns_last_pid and then (quickly) does a clone(). This works most of the
time, but it is racy. It is also slow as it requires multiple syscalls.
Extending clone3() to support *set_tid makes it possible restore a
process using CRIU without accessing /proc/sys/kernel/ns_last_pid and
race free (as long as the desired PID/TID is available).
This clone3() extension places the same restrictions (CAP_SYS_ADMIN)
on clone3() with *set_tid as they are currently in place for ns_last_pid.
The original version of this change was using a single value for
set_tid. At the 2019 LPC, after presenting set_tid, it was, however,
decided to change set_tid to an array to enable setting the PID of a
process in multiple PID namespaces at the same time. If a process is
created in a PID namespace it is possible to influence the PID inside
and outside of the PID namespace. Details also in the corresponding
selftest.
To create a process with the following PIDs:
PID NS level Requested PID
0 (host) 31496
1 42
2 1
For that example the two newly introduced parameters to struct
clone_args (set_tid and set_tid_size) would need to be:
set_tid[0] = 1;
set_tid[1] = 42;
set_tid[2] = 31496;
set_tid_size = 3;
If only the PIDs of the two innermost nested PID namespaces should be
defined it would look like this:
set_tid[0] = 1;
set_tid[1] = 42;
set_tid_size = 2;
The PID of the newly created process would then be the next available
free PID in the PID namespace level 0 (host) and 42 in the PID namespace
at level 1 and the PID of the process in the innermost PID namespace
would be 1.
The set_tid array is used to specify the PID of a process starting
from the innermost nested PID namespaces up to set_tid_size PID namespaces.
set_tid_size cannot be larger then the current PID namespace level.
Signed-off-by: Adrian Reber <areber@redhat.com>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Dmitry Safonov <0x7f454c46@gmail.com>
Acked-by: Andrei Vagin <avagin@gmail.com>
Link: https://lore.kernel.org/r/20191115123621.142252-1-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Allow FENTRY/FEXIT BPF programs to attach to other BPF programs of any type
including their subprograms. This feature allows snooping on input and output
packets in XDP, TC programs including their return values. In order to do that
the verifier needs to track types not only of vmlinux, but types of other BPF
programs as well. The verifier also needs to translate uapi/linux/bpf.h types
used by networking programs into kernel internal BTF types used by FENTRY/FEXIT
BPF programs. In some cases LLVM optimizations can remove arguments from BPF
subprograms without adjusting BTF info that LLVM backend knows. When BTF info
disagrees with actual types that the verifiers sees the BPF trampoline has to
fallback to conservative and treat all arguments as u64. The FENTRY/FEXIT
program can still attach to such subprograms, but it won't be able to recognize
pointer types like 'struct sk_buff *' and it won't be able to pass them to
bpf_skb_output() for dumping packets to user space. The FENTRY/FEXIT program
would need to use bpf_probe_read_kernel() instead.
The BPF_PROG_LOAD command is extended with attach_prog_fd field. When it's set
to zero the attach_btf_id is one vmlinux BTF type ids. When attach_prog_fd
points to previously loaded BPF program the attach_btf_id is BTF type id of
main function or one of its subprograms.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-18-ast@kernel.org
Make the verifier check that BTF types of function arguments match actual types
passed into top-level BPF program and into BPF-to-BPF calls. If types match
such BPF programs and sub-programs will have full support of BPF trampoline. If
types mismatch the trampoline has to be conservative. It has to save/restore
five program arguments and assume 64-bit scalars.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-17-ast@kernel.org
Annotate BPF program context types with program-side type and kernel-side type.
This type information is used by the verifier. btf_get_prog_ctx_type() is
used in the later patches to verify that BTF type of ctx in BPF program matches to
kernel expected ctx type. For example, the XDP program type is:
BPF_PROG_TYPE(BPF_PROG_TYPE_XDP, xdp, struct xdp_md, struct xdp_buff)
That means that XDP program should be written as:
int xdp_prog(struct xdp_md *ctx) { ... }
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-16-ast@kernel.org
btf_resolve_helper_id() caching logic is a bit racy, since under root the
verifier can verify several programs in parallel. Fix it with READ/WRITE_ONCE.
Fix the type as well, since error is also recorded.
Fixes: a7658e1a41 ("bpf: Check types of arguments passed into helpers")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-15-ast@kernel.org
Introduce BPF trampoline concept to allow kernel code to call into BPF programs
with practically zero overhead. The trampoline generation logic is
architecture dependent. It's converting native calling convention into BPF
calling convention. BPF ISA is 64-bit (even on 32-bit architectures). The
registers R1 to R5 are used to pass arguments into BPF functions. The main BPF
program accepts only single argument "ctx" in R1. Whereas CPU native calling
convention is different. x86-64 is passing first 6 arguments in registers
and the rest on the stack. x86-32 is passing first 3 arguments in registers.
sparc64 is passing first 6 in registers. And so on.
The trampolines between BPF and kernel already exist. BPF_CALL_x macros in
include/linux/filter.h statically compile trampolines from BPF into kernel
helpers. They convert up to five u64 arguments into kernel C pointers and
integers. On 64-bit architectures this BPF_to_kernel trampolines are nops. On
32-bit architecture they're meaningful.
The opposite job kernel_to_BPF trampolines is done by CAST_TO_U64 macros and
__bpf_trace_##call() shim functions in include/trace/bpf_probe.h. They convert
kernel function arguments into array of u64s that BPF program consumes via
R1=ctx pointer.
This patch set is doing the same job as __bpf_trace_##call() static
trampolines, but dynamically for any kernel function. There are ~22k global
kernel functions that are attachable via nop at function entry. The function
arguments and types are described in BTF. The job of btf_distill_func_proto()
function is to extract useful information from BTF into "function model" that
architecture dependent trampoline generators will use to generate assembly code
to cast kernel function arguments into array of u64s. For example the kernel
function eth_type_trans has two pointers. They will be casted to u64 and stored
into stack of generated trampoline. The pointer to that stack space will be
passed into BPF program in R1. On x86-64 such generated trampoline will consume
16 bytes of stack and two stores of %rdi and %rsi into stack. The verifier will
make sure that only two u64 are accessed read-only by BPF program. The verifier
will also recognize the precise type of the pointers being accessed and will
not allow typecasting of the pointer to a different type within BPF program.
The tracing use case in the datacenter demonstrated that certain key kernel
functions have (like tcp_retransmit_skb) have 2 or more kprobes that are always
active. Other functions have both kprobe and kretprobe. So it is essential to
keep both kernel code and BPF programs executing at maximum speed. Hence
generated BPF trampoline is re-generated every time new program is attached or
detached to maintain maximum performance.
To avoid the high cost of retpoline the attached BPF programs are called
directly. __bpf_prog_enter/exit() are used to support per-program execution
stats. In the future this logic will be optimized further by adding support
for bpf_stats_enabled_key inside generated assembly code. Introduction of
preemptible and sleepable BPF programs will completely remove the need to call
to __bpf_prog_enter/exit().
Detach of a BPF program from the trampoline should not fail. To avoid memory
allocation in detach path the half of the page is used as a reserve and flipped
after each attach/detach. 2k bytes is enough to call 40+ BPF programs directly
which is enough for BPF tracing use cases. This limit can be increased in the
future.
BPF_TRACE_FENTRY programs have access to raw kernel function arguments while
BPF_TRACE_FEXIT programs have access to kernel return value as well. Often
kprobe BPF program remembers function arguments in a map while kretprobe
fetches arguments from a map and analyzes them together with return value.
BPF_TRACE_FEXIT accelerates this typical use case.
Recursion prevention for kprobe BPF programs is done via per-cpu
bpf_prog_active counter. In practice that turned out to be a mistake. It
caused programs to randomly skip execution. The tracing tools missed results
they were looking for. Hence BPF trampoline doesn't provide builtin recursion
prevention. It's a job of BPF program itself and will be addressed in the
follow up patches.
BPF trampoline is intended to be used beyond tracing and fentry/fexit use cases
in the future. For example to remove retpoline cost from XDP programs.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-5-ast@kernel.org
Add bpf_arch_text_poke() helper that is used by BPF trampoline logic to patch
nops/calls in kernel text into calls into BPF trampoline and to patch
calls/nops inside BPF programs too.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191114185720.1641606-4-ast@kernel.org
Currently passing alignment greater than 4 to bpf_jit_binary_alloc does
not work: in such cases it silently aligns only to 4 bytes.
On s390, in order to load a constant from memory in a large (>512k) BPF
program, one must use lgrl instruction, whose memory operand must be
aligned on an 8-byte boundary.
This patch makes it possible to request 8-byte alignment from
bpf_jit_binary_alloc, and also makes it issue a warning when an
unsupported alignment is requested.
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191115123722.58462-1-iii@linux.ibm.com
An additional check has been recently added to ensure that a RCU related lock
is held while the RCU list is iterated.
The `pwqs' are sometimes iterated without a RCU lock but with the &wq->mutex
acquired leading to a warning.
Teach list_for_each_entry_rcu() that the RCU usage is okay if &wq->mutex
is acquired during the list traversal.
Fixes: 28875945ba ("rcu: Add support for consolidated-RCU reader checking")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Both unregister_ftrace_direct() and modify_ftrace_direct() needs to
normalize the ip passed in to match the rec->ip, as it is acceptable to have
the ip on the ftrace call site but not the start. There are also common
validity checks with the record found by the ip, these should be done for
both unregister_ftrace_direct() and modify_ftrace_direct().
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As an instruction pointer passed into register_ftrace_direct() may just
exist on the ftrace call site, but may not be the start of the call site
itself, register_ftrace_direct() still needs to update test if a direct call
exists on the normalized site, as only one direct call is allowed at any one
time.
Fixes: 763e34e74b ("ftrace: Add register_ftrace_direct()")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The direct->count wasn't being updated properly, where it only was updated
when the first entry was added, but should be updated every time.
Fixes: 013bf0da04 ("ftrace: Add ftrace_find_direct_func()")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Robust futexes utilize the robust_list mechanism to allow the kernel to
release futexes which are held when a task exits. The exit can be voluntary
or caused by a signal or fault. This prevents that waiters block forever.
The futex operations in user space store a pointer to the futex they are
either locking or unlocking in the op_pending member of the per task robust
list.
After a lock operation has succeeded the futex is queued in the robust list
linked list and the op_pending pointer is cleared.
After an unlock operation has succeeded the futex is removed from the
robust list linked list and the op_pending pointer is cleared.
The robust list exit code checks for the pending operation and any futex
which is queued in the linked list. It carefully checks whether the futex
value is the TID of the exiting task. If so, it sets the OWNER_DIED bit and
tries to wake up a potential waiter.
This is race free for the lock operation but unlock has two race scenarios
where waiters might not be woken up. These issues can be observed with
regular robust pthread mutexes. PI aware pthread mutexes are not affected.
(1) Unlocking task is killed after unlocking the futex value in user space
before being able to wake a waiter.
pthread_mutex_unlock()
|
V
atomic_exchange_rel (&mutex->__data.__lock, 0)
<------------------------killed
lll_futex_wake () |
|
|(__lock = 0)
|(enter kernel)
|
V
do_exit()
exit_mm()
mm_release()
exit_robust_list()
handle_futex_death()
|
|(__lock = 0)
|(uval = 0)
|
V
if ((uval & FUTEX_TID_MASK) != task_pid_vnr(curr))
return 0;
The sanity check which ensures that the user space futex is owned by
the exiting task prevents the wakeup of waiters which in consequence
block infinitely.
(2) Waiting task is killed after a wakeup and before it can acquire the
futex in user space.
OWNER WAITER
futex_wait()
pthread_mutex_unlock() |
| |
|(__lock = 0) |
| |
V |
futex_wake() ------------> wakeup()
|
|(return to userspace)
|(__lock = 0)
|
V
oldval = mutex->__data.__lock
<-----------------killed
atomic_compare_and_exchange_val_acq (&mutex->__data.__lock, |
id | assume_other_futex_waiters, 0) |
|
|
(enter kernel)|
|
V
do_exit()
|
|
V
handle_futex_death()
|
|(__lock = 0)
|(uval = 0)
|
V
if ((uval & FUTEX_TID_MASK) != task_pid_vnr(curr))
return 0;
The sanity check which ensures that the user space futex is owned
by the exiting task prevents the wakeup of waiters, which seems to
be correct as the exiting task does not own the futex value, but
the consequence is that other waiters wont be woken up and block
infinitely.
In both scenarios the following conditions are true:
- task->robust_list->list_op_pending != NULL
- user space futex value == 0
- Regular futex (not PI)
If these conditions are met then it is reasonably safe to wake up a
potential waiter in order to prevent the above problems.
As this might be a false positive it can cause spurious wakeups, but the
waiter side has to handle other types of unrelated wakeups, e.g. signals
gracefully anyway. So such a spurious wakeup will not affect the
correctness of these operations.
This workaround must not touch the user space futex value and cannot set
the OWNER_DIED bit because the lock value is 0, i.e. uncontended. Setting
OWNER_DIED in this case would result in inconsistent state and subsequently
in malfunction of the owner died handling in user space.
The rest of the user space state is still consistent as no other task can
observe the list_op_pending entry in the exiting tasks robust list.
The eventually woken up waiter will observe the uncontended lock value and
take it over.
[ tglx: Massaged changelog and comment. Made the return explicit and not
depend on the subsequent check and added constants to hand into
handle_futex_death() instead of plain numbers. Fixed a few coding
style issues. ]
Fixes: 0771dfefc9 ("[PATCH] lightweight robust futexes: core")
Signed-off-by: Yang Tao <yang.tao172@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1573010582-35297-1-git-send-email-wang.yi59@zte.com.cn
Link: https://lkml.kernel.org/r/20191106224555.943191378@linutronix.de
Pull misc vfs fixes from Al Viro:
"Assorted fixes all over the place; some of that is -stable fodder,
some regressions from the last window"
* 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
ecryptfs_lookup_interpose(): lower_dentry->d_parent is not stable either
ecryptfs_lookup_interpose(): lower_dentry->d_inode is not stable
ecryptfs: fix unlink and rmdir in face of underlying fs modifications
audit_get_nd(): don't unlock parent too early
exportfs_decode_fh(): negative pinned may become positive without the parent locked
cgroup: don't put ERR_PTR() into fc->root
autofs: fix a leak in autofs_expire_indirect()
aio: Fix io_pgetevents() struct __compat_aio_sigset layout
fs/namespace.c: fix use-after-free of mount in mnt_warn_timestamp_expiry()
Increase the maximum allowed count of synthetic event fields from 16 to 32
in order to allow for larger-than-usual events.
Link: http://lkml.kernel.org/r/20191115091730.9192-1-dedekind1@gmail.com
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Artem Bityutskiy <artem.bityutskiy@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
At the moment, the compilation of the old time32 system calls depends
purely on the architecture. As systems with new libc based on 64-bit
time_t are getting deployed, even architectures that previously supported
these (notably x86-32 and arm32 but also many others) no longer depend on
them, and removing them from a kernel image results in a smaller kernel
binary, the same way we can leave out many other optional system calls.
More importantly, on an embedded system that needs to keep working
beyond year 2038, any user space program calling these system calls
is likely a bug, so removing them from the kernel image does provide
an extra debugging help for finding broken applications.
I've gone back and forth on hiding this option unless CONFIG_EXPERT
is set. This version leaves it visible based on the logic that
eventually it will be turned off indefinitely.
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
There is no 64-bit version of getitimer/setitimer since that is not
actually needed. However, the implementation is built around the
deprecated 'struct timeval' type.
Change the code to use timespec64 internally to reduce the dependencies
on timeval and associated helper functions.
Minor adjustments in the code are needed to make the native and compat
version work the same way, and to keep the range check working after
the conversion.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Preparing for a change to the itimer internals, stop using the
do_setitimer() symbol and instead use a new higher-level interface.
The do_getitimer()/do_setitimer functions can now be made static,
allowing the compiler to potentially produce better object code.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The itimer handling for the old alpha osf_setitimer/osf_getitimer
system calls is identical to the compat version of getitimer/setitimer,
so just use those directly.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The structure is only used in one place, moving it there simplifies the
interface and helps with later changes to this code.
Rename it to match the other time32 structures in the process.
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
The compat_get_timeval() and timeval_valid() interfaces are deprecated
and getting removed along with the definition of struct timeval itself.
Change the two implementations of the settimeofday() system call to
open-code these helpers and completely avoid references to timeval.
The timeval_valid() call is not needed any more here, only a check to
avoid overflowing tv_nsec during the multiplication, as there is another
range check in do_sys_settimeofday64().
Tested-by: syzbot+dccce9b26ba09ca49966@syzkaller.appspotmail.com
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
All of the remaining syscalls that pass a timeval (gettimeofday, utime,
futimesat) can trivially be changed to pass a __kernel_old_timeval
instead, which has a compatible layout, but avoids ambiguity with
the timeval type in user space.
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
There are two 'struct timeval' fields in 'struct rusage'.
Unfortunately the definition of timeval is now ambiguous when used in
user space with a libc that has a 64-bit time_t, and this also changes
the 'rusage' definition in user space in a way that is incompatible with
the system call interface.
While there is no good solution to avoid all ambiguity here, change
the definition in the kernel headers to be compatible with the kernel
ABI, using __kernel_old_timeval as an unambiguous base type.
In previous discussions, there was also a plan to add a replacement
for rusage based on 64-bit timestamps and nanosecond resolution,
i.e. 'struct __kernel_timespec'. I have patches for that as well,
if anyone thinks we should do that.
Reviewed-by: Cyrill Gorcunov <gorcunov@gmail.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
This is mainly a patch for clarification, and to let us remove
the time_t definition from the kernel to prevent new users from
creeping in that might not be y2038-safe.
All remaining uses of 'time_t' or '__kernel_time_t' are part of
the user API that cannot be changed by that either have a
replacement or that do not suffer from the y2038 overflow.
Acked-by: Deepa Dinamani <deepa.kernel@gmail.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Exporting perf_event_pause() as an external accessor for kernel users (such
as KVM) who may do both disable perf_event and read count with just one
time to hold perf_event_ctx_lock. Also the value could be reset optionally.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Currently, perf_event_period() is used by user tools via ioctl. Based on
naming convention, exporting perf_event_period() for kernel users (such
as KVM) who may recalibrate the event period for their assigned counter
according to their requirements.
The perf_event_period() is an external accessor, just like the
perf_event_{en,dis}able() and should thus use perf_event_ctx_lock().
Suggested-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Like Xu <like.xu@linux.intel.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Fix the race between load and unload a kernel module.
sys_delete_module()
try_stop_module()
mod->state = _GOING
add_unformed_module()
old = find_module_all()
(old->state == _GOING =>
wait_event_interruptible())
During pre-condition
finished_loading() rets 0
schedule()
(never gets waken up later)
free_module()
mod->state = _UNFORMED
list_del_rcu(&mod->list)
(dels mod from "modules" list)
return
The race above leads to modprobe hanging forever on loading
a module.
Error paths on loading module call wake_up_all(&module_wq) after
freeing module, so let's do the same on straight module unload.
Fixes: 6e6de3dee5 ("kernel/module.c: Only return -EEXIST for modules that have finished loading")
Reviewed-by: Prarit Bhargava <prarit@redhat.com>
Signed-off-by: Konstantin Khorenko <khorenko@virtuozzo.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
uclamp_update_active() should perform the update when
p->uclamp[clamp_id].active is true. But when the logic was inverted in
[1], the if condition wasn't inverted correctly too.
[1] https://lore.kernel.org/lkml/20190902073836.GO2369@hirez.programming.kicks-ass.net/
Reported-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Patrick Bellasi <patrick.bellasi@matbug.net>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: babbe170e0 ("sched/uclamp: Update CPU's refcount on TG's clamp changes")
Link: https://lkml.kernel.org/r/20191114211052.15116-1-qais.yousef@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While attempting to clear the busy bit at the end of a work execution,
atomic_cmpxchg() expects the value of the flags with the pending bit
cleared as the old value. However by mistake the value of the flags is
passed without clearing the pending bit first.
As a result, clearing the busy bit fails and irq_work_sync() may stall:
watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [blktrace:4948]
CPU: 0 PID: 4948 Comm: blktrace Not tainted 5.4.0-rc7-00003-gfeb4a51323bab #1
RIP: 0010:irq_work_sync+0x4/0x10
Call Trace:
relay_close_buf+0x19/0x50
relay_close+0x64/0x100
blk_trace_free+0x1f/0x50
__blk_trace_remove+0x1e/0x30
blk_trace_ioctl+0x11b/0x140
blkdev_ioctl+0x6c1/0xa40
block_ioctl+0x39/0x40
do_vfs_ioctl+0xa5/0x700
ksys_ioctl+0x70/0x80
__x64_sys_ioctl+0x16/0x20
do_syscall_64+0x5b/0x1d0
entry_SYSCALL_64_after_hwframe+0x44/0xa9
So clear the appropriate bit before passing the old flags to cmpxchg().
Fixes: feb4a51323 ("irq_work: Slightly simplify IRQ_WORK_PENDING clearing")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Reported-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Leonard Crestez <leonard.crestez@nxp.com>
Link: https://lkml.kernel.org/r/20191113171201.14032-1-frederic@kernel.org
Add a new function modify_ftrace_direct() that will allow a user to update
an existing direct caller to a new trampoline, without missing hits due to
unregistering one and then adding another.
Link: https://lore.kernel.org/r/20191109022907.6zzo6orhxpt5n2sv@ast-mbp.dhcp.thefacebook.com
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The latency_fsnotify() stub when the function is not defined, was missing
the "inline".
Link: https://lore.kernel.org/r/20191115140213.74c5efe7@canb.auug.org.au
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
743210386c ("cgroup: use cgrp->kn->id as the cgroup ID") added WARN
which triggers if cgroup_id(root_cgrp) is not 1. This is fine on
64bit ino archs but on 32bit archs cgroup ID is ((gen << 32) | ino)
and gen starts at 1, so the root id is 0x1_0000_0001 instead of 1
always triggering the WARN.
What we wanna make sure is that the ino part is 1. Fix it.
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Fixes: 743210386c ("cgroup: use cgrp->kn->id as the cgroup ID")
Signed-off-by: Tejun Heo <tj@kernel.org>
There was a stray tab in the help text of the aforementioned config
option which showed like this:
The "print fmt" of the trace events will show the enum/sizeof names
instead of their values. This can cause problems for user space tools
...
in menuconfig. Remove it and end a sentence with a fullstop.
No functional changes.
Link: http://lkml.kernel.org/r/20191112174219.10933-1-bp@alien8.de
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Without this, buffers can be printed with __print_array macro that has
no formatting options and can be hard to read. The other way is to
mimic formatting capability with multiple calls of trace event with one
call per row which gives performance impact and different timestamp in
each row.
Link: http://lkml.kernel.org/r/1573130738-29390-2-git-send-email-piotrx.maziarz@linux.intel.com
Signed-off-by: Piotr Maziarz <piotrx.maziarz@linux.intel.com>
Signed-off-by: Cezary Rojewski <cezary.rojewski@intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Check whether the non-suffixed symbol is notrace, since suffixed
symbols are generated by the compilers for optimization. Based on
these suffixed symbols, notrace check might not work because
some of them are just a partial code of the original function.
(e.g. cold-cache (unlikely) code is separated from original
function as FUNCTION.cold.XX)
For example, without this fix,
# echo p device_add.cold.67 > /sys/kernel/debug/tracing/kprobe_events
sh: write error: Invalid argument
# cat /sys/kernel/debug/tracing/error_log
[ 135.491035] trace_kprobe: error: Failed to register probe event
Command: p device_add.cold.67
^
# dmesg | tail -n 1
[ 135.488599] trace_kprobe: Could not probe notrace function device_add.cold.67
With this,
# echo p device_add.cold.66 > /sys/kernel/debug/tracing/kprobe_events
# cat /sys/kernel/debug/kprobes/list
ffffffff81599de9 k device_add.cold.66+0x0 [DISABLED]
Actually, kprobe blacklist already did similar thing,
see within_kprobe_blacklist().
Link: http://lkml.kernel.org/r/157233790394.6706.18243942030937189679.stgit@devnote2
Fixes: 45408c4f92 ("tracing: kprobes: Prohibit probing on notrace function")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fail to allocate memory for tgid_map, because it requires order-6 page.
detail as:
c3 sh: page allocation failure: order:6,
mode:0x140c0c0(GFP_KERNEL), nodemask=(null)
c3 sh cpuset=/ mems_allowed=0
c3 CPU: 3 PID: 5632 Comm: sh Tainted: G W O 4.14.133+ #10
c3 Hardware name: Generic DT based system
c3 Backtrace:
c3 [<c010bdbc>] (dump_backtrace) from [<c010c08c>](show_stack+0x18/0x1c)
c3 [<c010c074>] (show_stack) from [<c0993c54>](dump_stack+0x84/0xa4)
c3 [<c0993bd0>] (dump_stack) from [<c0229858>](warn_alloc+0xc4/0x19c)
c3 [<c0229798>] (warn_alloc) from [<c022a6e4>](__alloc_pages_nodemask+0xd18/0xf28)
c3 [<c02299cc>] (__alloc_pages_nodemask) from [<c0248344>](kmalloc_order+0x20/0x38)
c3 [<c0248324>] (kmalloc_order) from [<c0248380>](kmalloc_order_trace+0x24/0x108)
c3 [<c024835c>] (kmalloc_order_trace) from [<c01e6078>](set_tracer_flag+0xb0/0x158)
c3 [<c01e5fc8>] (set_tracer_flag) from [<c01e6404>](trace_options_core_write+0x7c/0xcc)
c3 [<c01e6388>] (trace_options_core_write) from [<c0278b1c>](__vfs_write+0x40/0x14c)
c3 [<c0278adc>] (__vfs_write) from [<c0278e10>](vfs_write+0xc4/0x198)
c3 [<c0278d4c>] (vfs_write) from [<c027906c>](SyS_write+0x6c/0xd0)
c3 [<c0279000>] (SyS_write) from [<c01079a0>](ret_fast_syscall+0x0/0x54)
Switch to use kvcalloc to avoid unexpected allocation failures.
Link: http://lkml.kernel.org/r/1571888070-24425-1-git-send-email-chunyan.zhang@unisoc.com
Signed-off-by: Yuming Han <yuming.han@unisoc.com>
Signed-off-by: Chunyan Zhang <chunyan.zhang@unisoc.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The C compiler is allowing more checks to make sure that function pointers
are assigned to the correct prototype function. Unfortunately, the function
graph tracer uses a special name with its assigned ftrace_graph_return
function pointer that maps to a stub function used by the function tracer
(ftrace_stub). The ftrace_graph_return variable is compared to the
ftrace_stub in some archs to know if the function graph tracer is enabled or
not. This means we can not just simply create a new function stub that
compares it without modifying all the archs.
Instead, have the linker script create a function_graph_stub that maps to
ftrace_stub, and this way we can define the prototype for it to match the
prototype of ftrace_graph_return, and make the compiler checks all happy!
Link: http://lkml.kernel.org/r/20191015090055.789a0aed@gandalf.local.home
Cc: linux-sh@vger.kernel.org
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Reported-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As part of commit f45d1225ad ("tracing: Kernel access to Ftrace
instances") we exported certain functions. Here, we are adding some additional
NULL checks to ensure safe usage by users of these APIs.
Link: http://lkml.kernel.org/r/1565805327-579-4-git-send-email-divya.indi@oracle.com
Signed-off-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A trace array can be destroyed from userspace or kernel. Verify if the
trace array exists before proceeding to destroy/remove it.
Link: http://lkml.kernel.org/r/1565805327-579-3-git-send-email-divya.indi@oracle.com
Reviewed-by: Aruna Ramakrishna <aruna.ramakrishna@oracle.com>
Signed-off-by: Divya Indi <divya.indi@oracle.com>
[ Removed unneeded braces ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Declare the newly introduced and exported APIs in the header file -
include/linux/trace.h. Moving previous declarations from
kernel/trace/trace.h to include/linux/trace.h.
Link: http://lkml.kernel.org/r/1565805327-579-2-git-send-email-divya.indi@oracle.com
Signed-off-by: Divya Indi <divya.indi@oracle.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The event_class_ftrace_##call and event_##call do not seem
to be used outside of trace_export.c so make them both static
to avoid a number of sparse warnings:
kernel/trace/trace_entries.h:59:1: warning: symbol 'event_class_ftrace_function' was not declared. Should it be static?
kernel/trace/trace_entries.h:59:1: warning: symbol '__event_function' was not declared. Should it be static?
kernel/trace/trace_entries.h:77:1: warning: symbol 'event_class_ftrace_funcgraph_entry' was not declared. Should it be static?
kernel/trace/trace_entries.h:77:1: warning: symbol '__event_funcgraph_entry' was not declared. Should it be static?
kernel/trace/trace_entries.h:93:1: warning: symbol 'event_class_ftrace_funcgraph_exit' was not declared. Should it be static?
kernel/trace/trace_entries.h:93:1: warning: symbol '__event_funcgraph_exit' was not declared. Should it be static?
kernel/trace/trace_entries.h:129:1: warning: symbol 'event_class_ftrace_context_switch' was not declared. Should it be static?
kernel/trace/trace_entries.h:129:1: warning: symbol '__event_context_switch' was not declared. Should it be static?
kernel/trace/trace_entries.h:149:1: warning: symbol 'event_class_ftrace_wakeup' was not declared. Should it be static?
kernel/trace/trace_entries.h:149:1: warning: symbol '__event_wakeup' was not declared. Should it be static?
kernel/trace/trace_entries.h:171:1: warning: symbol 'event_class_ftrace_kernel_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:171:1: warning: symbol '__event_kernel_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:191:1: warning: symbol 'event_class_ftrace_user_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:191:1: warning: symbol '__event_user_stack' was not declared. Should it be static?
kernel/trace/trace_entries.h:214:1: warning: symbol 'event_class_ftrace_bprint' was not declared. Should it be static?
kernel/trace/trace_entries.h:214:1: warning: symbol '__event_bprint' was not declared. Should it be static?
kernel/trace/trace_entries.h:230:1: warning: symbol 'event_class_ftrace_print' was not declared. Should it be static?
kernel/trace/trace_entries.h:230:1: warning: symbol '__event_print' was not declared. Should it be static?
kernel/trace/trace_entries.h:247:1: warning: symbol 'event_class_ftrace_raw_data' was not declared. Should it be static?
kernel/trace/trace_entries.h:247:1: warning: symbol '__event_raw_data' was not declared. Should it be static?
kernel/trace/trace_entries.h:262:1: warning: symbol 'event_class_ftrace_bputs' was not declared. Should it be static?
kernel/trace/trace_entries.h:262:1: warning: symbol '__event_bputs' was not declared. Should it be static?
kernel/trace/trace_entries.h:277:1: warning: symbol 'event_class_ftrace_mmiotrace_rw' was not declared. Should it be static?
kernel/trace/trace_entries.h:277:1: warning: symbol '__event_mmiotrace_rw' was not declared. Should it be static?
kernel/trace/trace_entries.h:298:1: warning: symbol 'event_class_ftrace_mmiotrace_map' was not declared. Should it be static?
kernel/trace/trace_entries.h:298:1: warning: symbol '__event_mmiotrace_map' was not declared. Should it be static?
kernel/trace/trace_entries.h:322:1: warning: symbol 'event_class_ftrace_branch' was not declared. Should it be static?
kernel/trace/trace_entries.h:322:1: warning: symbol '__event_branch' was not declared. Should it be static?
kernel/trace/trace_entries.h:343:1: warning: symbol 'event_class_ftrace_hwlat' was not declared. Should it be static?
kernel/trace/trace_entries.h:343:1: warning: symbol '__event_hwlat' was not declared. Should it be static?
Link: http://lkml.kernel.org/r/20191015121012.18824-1-ben.dooks@codethink.co.uk
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by CONFIG_PREEMPT_RT.
Both PREEMPT and PREEMPT_RT require the same functionality which today
depends on CONFIG_PREEMPT.
Add additional header output for PREEMPT_RT.
Link: http://lkml.kernel.org/r/20191015191821.11479-34-bigeasy@linutronix.de
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This burst feature enables the user to generate a burst of
preempt/irqsoff latencies. This makes it possible to test whether we
are able to detect latencies that systematically occur very close to
each other.
The maximum burst size is 10. We also create 10 identical test
functions, so that we get 10 different backtraces; this is useful
when we want to test whether we can detect all the latencies in a
burst. Otherwise, there would be no easy way of differentiating
between which latency in a burst was captured by the tracer.
In addition, there is a sysfs trigger, so that it's not necessary to
reload the module to repeat the test. The trigger will appear as
/sys/kernel/preemptirq_delay_test/trigger in sysfs.
Link: http://lkml.kernel.org/r/20191008220824.7911-3-viktor.rosendahl@gmail.com
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This patch implements the feature that the tracing_max_latency file,
e.g. /sys/kernel/debug/tracing/tracing_max_latency will receive
notifications through the fsnotify framework when a new latency is
available.
One particularly interesting use of this facility is when enabling
threshold tracing, through /sys/kernel/debug/tracing/tracing_thresh,
together with the preempt/irqsoff tracers. This makes it possible to
implement a user space program that can, with equal probability,
obtain traces of latencies that occur immediately after each other in
spite of the fact that the preempt/irqsoff tracers operate in overwrite
mode.
This facility works with the hwlat, preempt/irqsoff, and wakeup
tracers.
The tracers may call the latency_fsnotify() from places such as
__schedule() or do_idle(); this makes it impossible to call
queue_work() directly without risking a deadlock. The same would
happen with a softirq, kernel thread or tasklet. For this reason we
use the irq_work mechanism to call queue_work().
This patch creates a new workqueue. The reason for doing this is that
I wanted to use the WQ_UNBOUND and WQ_HIGHPRI flags. My thinking was
that WQ_UNBOUND might help with the latency in some important cases.
If we use:
queue_work(system_highpri_wq, &tr->fsnotify_work);
then the work will (almost) always execute on the same CPU but if we are
unlucky that CPU could be too busy while there could be another CPU in
the system that would be able to process the work soon enough.
queue_work_on() could be used to queue the work on another CPU but it
seems difficult to select the right CPU.
Link: http://lkml.kernel.org/r/20191008220824.7911-2-viktor.rosendahl@gmail.com
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Viktor Rosendahl (BMW) <viktor.rosendahl@gmail.com>
[ Added max() to have one compare for max latency ]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Looking for ways to shrink the size of the dyn_ftrace structure, knowing the
information about how many pages and the number of groups of those pages, is
useful in working out the best ways to save on memory.
This adds one info print on how many groups of pages were used to allocate
the ftrace dyn_ftrace structures, and also shows the number of pages and
groups in the dyn_ftrace_total_info (which is used for debugging).
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As testing for direct calls from the function graph tracer adds a little
overhead (which is a lot when tracing every function), add a counter that
can be used to test if function_graph tracer needs to test for a direct
caller or not.
It would have been nicer if we could use a static branch, but the static
branch logic fails when used within the function graph tracer trampoline.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As function_graph tracer modifies the return address to insert a trampoline
to trace the return of a function, it must be aware of a direct caller, as
when it gets called, the function's return address may not be at on the
stack where it expects. It may have to see if that return address points to
the a direct caller and adjust if it is.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add the start of the functionality to allow other trampolines to use the
ftrace mcount/fentry/nop location. This adds two new functions:
register_ftrace_direct() and unregister_ftrace_direct()
Both take two parameters: the first is the instruction address of where the
mcount/fentry/nop exists, and the second is the trampoline to have that
location called.
This will handle cases where ftrace is already used on that same location,
and will make it still work, where the registered direct called trampoline
will get called after all the registered ftrace callers are handled.
Currently, it will not allow for IP_MODIFY functions to be called at the
same locations, which include some kprobes and live kernel patching.
At this point, no architecture supports this. This is only the start of
implementing the framework.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since it stores CLOCK_BOOTTIME, not, as the name suggests,
CLOCK_REALTIME, let's rename ->real_start_time to ->start_bootime.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This changes "to the list" to "from the list" and also deletes the
obsolete comment about the "@nested" argument.
The "nested" argument was removed in this commit, earlier this year:
5facae4f35 ("locking/lockdep: Remove unused @nested argument from lock_release()").
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/20191104091252.GA31509@mwanda
Signed-off-by: Ingo Molnar <mingo@kernel.org>
AUX data can be used to annotate perf events such as performance counters
or tracepoints/breakpoints by including it in sample records when
PERF_SAMPLE_AUX flag is set. Such samples would be instrumental in debugging
and profiling by providing, for example, a history of instruction flow
leading up to the event's overflow.
The implementation makes use of grouping an AUX event with all the events
that wish to take samples of the AUX data, such that the former is the
group leader. The samplees should also specify the desired size of the AUX
sample via attr.aux_sample_size.
AUX capable PMUs need to explicitly add support for sampling, because it
relies on a new callback to take a snapshot of the buffer without touching
the event states.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: adrian.hunter@intel.com
Cc: mathieu.poirier@linaro.org
Link: https://lkml.kernel.org/r/20191025140835.53665-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It looks like a "static inline" has been missed in front
of the empty definition of perf_cgroup_switch() under
certain configurations.
Fixes the following sparse warning:
kernel/events/core.c:1035:1: warning: symbol 'perf_cgroup_switch' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191106132527.19977-1-ben.dooks@codethink.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
313ccb9615 ("perf: Allocate context task_ctx_data for child event")
makes the inherit path skip over the current event in case of task_ctx_data
allocation failure. This, however, is inconsistent with allocation failures
in perf_event_alloc(), which would abort the fork.
Correct this by returning an error code on task_ctx_data allocation
failure and failing the fork in that case.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191105075702.60319-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit
ab43762ef0 ("perf: Allow normal events to output AUX data")
added 'aux_output' bit to the attribute structure, which relies on AUX
events and grouping, neither of which is supported for the kernel events.
This notwithstanding, attempts have been made to use it in the kernel
code, suggesting the necessity of an explicit hard -EINVAL.
Fix this by rejecting attributes with aux_output set for kernel events.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191030134731.5437-3-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
A comment is in a wrong place in perf_event_create_kernel_counter().
Fix that.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: https://lkml.kernel.org/r/20191030134731.5437-2-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While discussing uncore event scheduling, I noticed we do not in fact
seem to dis-allow making uncore-cgroup events. Such events make no
sense what so ever because the cgroup is a CPU local state where
uncore counts across a number of CPUs.
Disallow them.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While seemingly harmless, __sched_fork() does hrtimer_init(), which,
when DEBUG_OBJETS, can end up doing allocations.
This then results in the following lock order:
rq->lock
zone->lock.rlock
batched_entropy_u64.lock
Which in turn causes deadlocks when we do wakeups while holding that
batched_entropy lock -- as the random code does.
Solve this by moving __sched_fork() out from under rq->lock. This is
safe because nothing there relies on rq->lock, as also evident from the
other __sched_fork() callsite.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: akpm@linux-foundation.org
Cc: bigeasy@linutronix.de
Cc: cl@linux.com
Cc: keescook@chromium.org
Cc: penberg@kernel.org
Cc: rientjes@google.com
Cc: thgarnie@google.com
Cc: tytso@mit.edu
Cc: will@kernel.org
Fixes: b7d5dc2107 ("random: add a spinlock_t to struct batched_entropy")
Link: https://lkml.kernel.org/r/20191001091837.GK4536@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 TSX Async Abort and iTLB Multihit mitigations from Thomas Gleixner:
"The performance deterioration departement is not proud at all of
presenting the seventh installment of speculation mitigations and
hardware misfeature workarounds:
1) TSX Async Abort (TAA) - 'The Annoying Affair'
TAA is a hardware vulnerability that allows unprivileged
speculative access to data which is available in various CPU
internal buffers by using asynchronous aborts within an Intel TSX
transactional region.
The mitigation depends on a microcode update providing a new MSR
which allows to disable TSX in the CPU. CPUs which have no
microcode update can be mitigated by disabling TSX in the BIOS if
the BIOS provides a tunable.
Newer CPUs will have a bit set which indicates that the CPU is not
vulnerable, but the MSR to disable TSX will be available
nevertheless as it is an architected MSR. That means the kernel
provides the ability to disable TSX on the kernel command line,
which is useful as TSX is a truly useful mechanism to accelerate
side channel attacks of all sorts.
2) iITLB Multihit (NX) - 'No eXcuses'
iTLB Multihit is an erratum where some Intel processors may incur
a machine check error, possibly resulting in an unrecoverable CPU
lockup, when an instruction fetch hits multiple entries in the
instruction TLB. This can occur when the page size is changed
along with either the physical address or cache type. A malicious
guest running on a virtualized system can exploit this erratum to
perform a denial of service attack.
The workaround is that KVM marks huge pages in the extended page
tables as not executable (NX). If the guest attempts to execute in
such a page, the page is broken down into 4k pages which are
marked executable. The workaround comes with a mechanism to
recover these shattered huge pages over time.
Both issues come with full documentation in the hardware
vulnerabilities section of the Linux kernel user's and administrator's
guide.
Thanks to all patch authors and reviewers who had the extraordinary
priviledge to be exposed to this nuisance.
Special thanks to Borislav Petkov for polishing the final TAA patch
set and to Paolo Bonzini for shepherding the KVM iTLB workarounds and
providing also the backports to stable kernels for those!"
* 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/speculation/taa: Fix printing of TAA_MSG_SMT on IBRS_ALL CPUs
Documentation: Add ITLB_MULTIHIT documentation
kvm: x86: mmu: Recovery of shattered NX large pages
kvm: Add helper function for creating VM worker threads
kvm: mmu: ITLB_MULTIHIT mitigation
cpu/speculation: Uninline and export CPU mitigations helpers
x86/cpu: Add Tremont to the cpu vulnerability whitelist
x86/bugs: Add ITLB_MULTIHIT bug infrastructure
x86/tsx: Add config options to set tsx=on|off|auto
x86/speculation/taa: Add documentation for TSX Async Abort
x86/tsx: Add "auto" option to the tsx= cmdline parameter
kvm/x86: Export MDS_NO=0 to guests when TSX is enabled
x86/speculation/taa: Add sysfs reporting for TSX Async Abort
x86/speculation/taa: Add mitigation for TSX Async Abort
x86/cpu: Add a "tsx=" cmdline option with TSX disabled by default
x86/cpu: Add a helper function x86_read_arch_cap_msr()
x86/msr: Add the IA32_TSX_CTRL MSR
cgroup ID is currently allocated using a dedicated per-hierarchy idr
and used internally and exposed through tracepoints and bpf. This is
confusing because there are tracepoints and other interfaces which use
the cgroupfs ino as IDs.
The preceding changes made kn->id exposed as ino as 64bit ino on
supported archs or ino+gen (low 32bits as ino, high gen). There's no
reason for cgroup to use different IDs. The kernfs IDs are unique and
userland can easily discover them and map them back to paths using
standard file operations.
This patch replaces cgroup IDs with kernfs IDs.
* cgroup_id() is added and all cgroup ID users are converted to use it.
* kernfs_node creation is moved to earlier during cgroup init so that
cgroup_id() is available during init.
* While at it, s/cgroup/cgrp/ in psi helpers for consistency.
* Fallback ID value is changed to 1 to be consistent with root cgroup
ID.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Each kernfs_node is identified with a 64bit ID. The low 32bit is
exposed as ino and the high gen. While this already allows using inos
as keys by looking up with wildcard generation number of 0, it's
adding unnecessary complications for 64bit ino archs which can
directly use kernfs_node IDs as inos to uniquely identify each cgroup
instance.
This patch exposes IDs directly as inos on 64bit ino archs. The
conversion is mostly straight-forward.
* 32bit ino archs behave the same as before. 64bit ino archs now use
the whole 64bit ID as ino and the generation number is fixed at 1.
* 64bit inos still use the same idr allocator which gurantees that the
lower 32bits identify the current live instance uniquely and the
high 32bits are incremented whenever the low bits wrap. As the
upper 32bits are no longer used as gen and we don't wanna start ino
allocation with 33rd bit set, the initial value for highbits
allocation is changed to 0 on 64bit ino archs.
* blktrace exposes two 32bit numbers - (INO,GEN) pair - to identify
the issuing cgroup. Userland builds FILEID_INO32_GEN fids from
these numbers to look up the cgroups. To remain compatible with the
behavior, always output (LOW32,HIGH32) which will be constructed
back to the original 64bit ID by __kernfs_fh_to_dentry().
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
kernfs_find_and_get_node_by_ino() looks the kernfs_node matching the
specified ino. On top of that, kernfs_get_node_by_id() and
kernfs_fh_get_inode() implement full ID matching by testing the rest
of ID.
On surface, confusingly, the two are slightly different in that the
latter uses 0 gen as wildcard while the former doesn't - does it mean
that the latter can't uniquely identify inodes w/ 0 gen? In practice,
this is a distinction without a difference because generation number
starts at 1. There are no actual IDs with 0 gen, so it can always
safely used as wildcard.
Let's simplify the code by renaming kernfs_find_and_get_node_by_ino()
to kernfs_find_and_get_node_by_id(), moving all lookup logics into it,
and removing now unnecessary kernfs_get_node_by_id().
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
kernfs_node->id is currently a union kernfs_node_id which represents
either a 32bit (ino, gen) pair or u64 value. I can't see much value
in the usage of the union - all that's needed is a 64bit ID which the
current code is already limited to. Using a union makes the code
unnecessarily complicated and prevents using 64bit ino without adding
practical benefits.
This patch drops union kernfs_node_id and makes kernfs_node->id a u64.
ino is stored in the lower 32bits and gen upper. Accessors -
kernfs[_id]_ino() and kernfs[_id]_gen() - are added to retrieve the
ino and gen. This simplifies ID handling less cumbersome and will
allow using 64bit inos on supported archs.
This patch doesn't make any functional changes.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Alexei Starovoitov <ast@kernel.org>
ns_to_timespec64() calls div_s64_rem(), which is a rather slow function on
32-bit architectures, as it cannot take advantage of the do_div()
optimizations for constant arguments.
Open-code the div_s64_rem() function in ns_to_timespec64(), so a constant
divider can be passed into the optimized div_u64_rem() function.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191108203435.112759-3-arnd@arndb.de
A cast to 'time_t' was accidentally left in place during the
conversion of __do_adjtimex() to 64-bit timestamps, so the
resulting value is incorrectly truncated.
Remove the cast so the 64-bit time gets propagated correctly.
Fixes: ead25417f8 ("timex: use __kernel_timex internally")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191108203435.112759-2-arnd@arndb.de
Currently, the cpuidle subsystem uses microseconds as the unit of
time which (among other things) causes the idle loop to incur some
integer division overhead for no clear benefit.
In order to allow cpuidle to measure time in nanoseconds, add two
new fields, exit_latency_ns and target_residency_ns, to represent the
exit latency and target residency of an idle state in nanoseconds,
respectively, to struct cpuidle_state and initialize them with the
help of the corresponding values in microseconds provided by drivers.
Additionally, change cpuidle_governor_latency_req() to return the
idle state exit latency constraint in nanoseconds.
Also meeasure idle state residency (last_residency_ns in struct
cpuidle_device and time_ns in struct cpuidle_driver) in nanoseconds
and update the cpuidle core and governors accordingly.
However, the menu governor still computes typical intervals in
microseconds to avoid integer overflows.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Doug Smythies <dsmythies@telus.net>
Tested-by: Doug Smythies <dsmythies@telus.net>
Pull cgroup fix from Tejun Heo:
"There's an inadvertent preemption point in ptrace_stop() which was
reliably triggering for a test scenario significantly slowing it down.
This contains Oleg's fix to remove the unwanted preemption point"
* 'for-5.4-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cgroup: freezer: call cgroup_enter_frozen() with preemption disabled in ptrace_stop()
This comment block explains why include/generated/compile.h is omitted,
but nothing about include/generated/autoconf.h, which might be more
difficult to understand. Add more comments.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
'pushd' ... 'popd' is the last bash-specific code in this script.
One way to avoid it is to run the code in a sub-shell.
With that addressed, you can run this script with sh.
I replaced $(BASH) with $(CONFIG_SHELL), and I changed the hashbang
to #!/bin/sh.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This script copies headers by the cpio command twice; first from
srctree, and then from objtree. However, when we building in-tree,
we know the srctree and the objtree are the same. That is, all the
headers copied by the first cpio are overwritten by the second one.
Skip the first cpio when we are building in-tree.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
This script computes md5sum of headers in srctree and in objtree.
However, when we are building in-tree, we know the srctree and the
objtree are the same. That is, we end up with the same computation
twice. In fact, the first two lines of kernel/kheaders.md5 are always
the same for in-tree builds.
Unify the two md5sum calculations.
For in-tree builds ($building_out_of_srctree is empty), we check
only two directories, "include", and "arch/$SRCARCH/include".
For out-of-tree builds ($building_out_of_srctree is 1), we check
4 directories, "$srctree/include", "$srctree/arch/$SRCARCH/include",
"include", and "arch/$SRCARCH/include" since we know they are all
different.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
The 'head' and 'tail' commands can take a file path directly.
So, you do not need to run 'cat'.
cat kernel/kheaders.md5 | head -1
... is equivalent to:
head -1 kernel/kheaders.md5
and the latter saves forking one process.
While I was here, I replaced 'head -1' with 'head -n 1'.
I also replaced '==' with '=' since we do not have a good reason to
use the bashism.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
With modern NIC, it is not unusual having about ~256,000 active dma
mappings and a hash size of 1024 buckets is too small.
Forcing full cache line per bucket does not seem useful, especially now
that we have contention on free_entries_lock for allocations and freeing
of entries. Better use the space to fit more buckets.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Move all fields used during exact match lookups to the first cache line.
This makes debug_dma_mapping_error() and friends about 50% faster.
Since it removes two 32bit holes, force a cacheline alignment on struct
dma_debug_entry.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Integrate the generic dma remapping implementation into the main flow.
This prepares for architectures like xtensa that use an uncached
segment for pages in the kernel mapping, but can also remap highmem
from CMA. To simplify that implementation we now always deduct the
page from the physical address via the DMA address instead of the
virtual address.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
For dma-direct we know that the DMA address is an encoding of the
physical address that we can trivially decode. Use that fact to
provide implementations that do not need the arch_dma_coherent_to_pfn
architecture hook. Note that we still can only support mmap of
non-coherent memory only if the architecture provides a way to set an
uncached bit in the page tables. This must be true for architectures
that use the generic remap helpers, but other architectures can also
manually select it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
My commit b0c51f1584 ("stacktrace: Don't skip first entry on
noncurrent tasks") adds one or zero to skipnr by "!!(current == tsk)".
But the C99 standard says:
The == (equal to) and != (not equal to) operators are
...
Each of the operators yields 1 if the specified relation is true and 0
if it is false.
So there is no need to prepend the above expression by "!!" -- remove it.
Reported-by: Joe Perches <joe@perches.com>
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191111092647.27419-1-jslaby@suse.cz
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Instead of fetching the value of flags and perform an xchg() to clear
a bit, just use atomic_fetch_andnot() that is more suitable to do that
job in one operation while keeping the full ordering.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191108160858.31665-4-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When irq_work_claim() finds IRQ_WORK_PENDING flag already set, we just
return and don't raise a new IPI. We expect the destination to see
and handle our latest updades thanks to the pairing atomic_xchg()
in irq_work_run_list().
But cmpxchg() doesn't guarantee a full memory barrier upon failure. So
it's possible that the destination misses our latest updates.
So use atomic_fetch_or() instead that is unconditionally fully ordered
and also performs exactly what we want here and simplify the code.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191108160858.31665-3-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We need to convert flags to atomic_t in order to later fix an ordering
issue on atomic_cmpxchg() failure. This will allow us to use atomic_fetch_or().
Also clarify the nature of those flags.
[ mingo: Converted two more usage site the original patch missed. ]
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E . McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191108160858.31665-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Ever since we moved the sched_class definitions into their own files,
the constant expression {fair,idle}_sched_class.pick_next_task() is
not in fact a compile time constant anymore and results in an indirect
call (barring LTO).
Fix that by exposing pick_next_task_{fair,idle}() directly, this gets
rid of the indirect call (and RETPOLINE) on the fast path.
Also remove the unlikely() from the idle case, it is in fact /the/ way
we select idle -- and that is a very common thing to do.
Performance for will-it-scale/sched_yield improves by 2% (as reported
by 0-day).
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bsegall@google.com
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: ktkhai@virtuozzo.com
Cc: mgorman@suse.de
Cc: qais.yousef@arm.com
Cc: qperret@google.com
Cc: rostedt@goodmis.org
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Link: https://lkml.kernel.org/r/20191108131909.603037345@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for timekeepoing and clocksource drivers:
- VDSO data was updated conditional on the availability of a VDSO
capable clocksource. This causes the VDSO functions which do not
depend on a VDSO capable clocksource to operate on stale data.
Always update unconditionally.
- Prevent a double free in the mediatek driver
- Use the proper helper in the sh_mtu2 driver so it won't attempt to
initialize non-existing interrupts"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping/vsyscall: Update VDSO data unconditionally
clocksource/drivers/sh_mtu2: Do not loop using platform_get_irq_by_name()
clocksource/drivers/mediatek: Fix error handling
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for scheduler regressions:
- Plug a subtle race condition which was introduced with the rework
of the next task selection functionality. The change of task
properties became unprotected which can be observed inconsistently
causing state corruption.
- A trivial compile fix for CONFIG_CGROUPS=n"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched: Fix pick_next_task() vs 'change' pattern race
sched/core: Fix compilation error when cgroup not selected
Pull irq fixlet from Thomas Gleixner:
"A trivial fix for a kernel doc regression where an argument change was
not reflected in the documentation"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
irq/irqdomain: Update __irq_domain_alloc_fwnode() function documentation
Pull stacktrace fix from Thomas Gleixner:
"A small fix for a stacktrace regression.
Saving a stacktrace for a foreign task skipped an extra entry which
makes e.g. the output of /proc/$PID/stack incomplete"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stacktrace: Don't skip first entry on noncurrent tasks
if the child has been negative and just went positive
under us, we want coherent d_is_positive() and ->d_inode.
Don't unlock the parent until we'd done that work...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
the caller of ->get_tree() expects NULL left there on error...
Reported-by: Thibaut Sautereau <thibaut@sautereau.fr>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
One conflict in the BPF samples Makefile, some fixes in 'net' whilst
we were converting over to Makefile.target rules in 'net-next'.
Signed-off-by: David S. Miller <davem@davemloft.net>
Pull networking fixes from David Miller:
1) BPF sample build fixes from Björn Töpel
2) Fix powerpc bpf tail call implementation, from Eric Dumazet.
3) DCCP leaks jiffies on the wire, fix also from Eric Dumazet.
4) Fix crash in ebtables when using dnat target, from Florian Westphal.
5) Fix port disable handling whne removing bcm_sf2 driver, from Florian
Fainelli.
6) Fix kTLS sk_msg trim on fallback to copy mode, from Jakub Kicinski.
7) Various KCSAN fixes all over the networking, from Eric Dumazet.
8) Memory leaks in mlx5 driver, from Alex Vesker.
9) SMC interface refcounting fix, from Ursula Braun.
10) TSO descriptor handling fixes in stmmac driver, from Jose Abreu.
11) Add a TX lock to synchonize the kTLS TX path properly with crypto
operations. From Jakub Kicinski.
12) Sock refcount during shutdown fix in vsock/virtio code, from Stefano
Garzarella.
13) Infinite loop in Intel ice driver, from Colin Ian King.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (108 commits)
ixgbe: need_wakeup flag might not be set for Tx
i40e: need_wakeup flag might not be set for Tx
igb/igc: use ktime accessors for skb->tstamp
i40e: Fix for ethtool -m issue on X722 NIC
iavf: initialize ITRN registers with correct values
ice: fix potential infinite loop because loop counter being too small
qede: fix NULL pointer deref in __qede_remove()
net: fix data-race in neigh_event_send()
vsock/virtio: fix sock refcnt holding during the shutdown
net: ethernet: octeon_mgmt: Account for second possible VLAN header
mac80211: fix station inactive_time shortly after boot
net/fq_impl: Switch to kvmalloc() for memory allocation
mac80211: fix ieee80211_txq_setup_flows() failure path
ipv4: Fix table id reference in fib_sync_down_addr
ipv6: fixes rt6_probe() and fib6_nh->last_probe init
net: hns: Fix the stray netpoll locks causing deadlock in NAPI path
net: usb: qmi_wwan: add support for DW5821e with eSIM support
CDC-NCM: handle incomplete transfer of MTU
nfc: netlink: fix double device reference drop
NFC: st21nfca: fix double free
...
Commit 67692435c4 ("sched: Rework pick_next_task() slow-path")
inadvertly introduced a race because it changed a previously
unexplored dependency between dropping the rq->lock and
sched_class::put_prev_task().
The comments about dropping rq->lock, in for example
newidle_balance(), only mentions the task being current and ->on_cpu
being set. But when we look at the 'change' pattern (in for example
sched_setnuma()):
queued = task_on_rq_queued(p); /* p->on_rq == TASK_ON_RQ_QUEUED */
running = task_current(rq, p); /* rq->curr == p */
if (queued)
dequeue_task(...);
if (running)
put_prev_task(...);
/* change task properties */
if (queued)
enqueue_task(...);
if (running)
set_next_task(...);
It becomes obvious that if we do this after put_prev_task() has
already been called on @p, things go sideways. This is exactly what
the commit in question allows to happen when it does:
prev->sched_class->put_prev_task(rq, prev, rf);
if (!rq->nr_running)
newidle_balance(rq, rf);
The newidle_balance() call will drop rq->lock after we've called
put_prev_task() and that allows the above 'change' pattern to
interleave and mess up the state.
Furthermore, it turns out we lost the RT-pull when we put the last DL
task.
Fix both problems by extracting the balancing from put_prev_task() and
doing a multi-class balance() pass before put_prev_task().
Fixes: 67692435c4 ("sched: Rework pick_next_task() slow-path")
Reported-by: Quentin Perret <qperret@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Quentin Perret <qperret@google.com>
Tested-by: Valentin Schneider <valentin.schneider@arm.com>
When cgroup is disabled the following compilation error was hit
kernel/sched/core.c: In function ‘uclamp_update_active_tasks’:
kernel/sched/core.c:1081:23: error: storage size of ‘it’ isn’t known
struct css_task_iter it;
^~
kernel/sched/core.c:1084:2: error: implicit declaration of function ‘css_task_iter_start’; did you mean ‘__sg_page_iter_start’? [-Werror=implicit-function-declaration]
css_task_iter_start(css, 0, &it);
^~~~~~~~~~~~~~~~~~~
__sg_page_iter_start
kernel/sched/core.c:1085:14: error: implicit declaration of function ‘css_task_iter_next’; did you mean ‘__sg_page_iter_next’? [-Werror=implicit-function-declaration]
while ((p = css_task_iter_next(&it))) {
^~~~~~~~~~~~~~~~~~
__sg_page_iter_next
kernel/sched/core.c:1091:2: error: implicit declaration of function ‘css_task_iter_end’; did you mean ‘get_task_cred’? [-Werror=implicit-function-declaration]
css_task_iter_end(&it);
^~~~~~~~~~~~~~~~~
get_task_cred
kernel/sched/core.c:1081:23: warning: unused variable ‘it’ [-Wunused-variable]
struct css_task_iter it;
^~
cc1: some warnings being treated as errors
make[2]: *** [kernel/sched/core.o] Error 1
Fix by protetion uclamp_update_active_tasks() with
CONFIG_UCLAMP_TASK_GROUP
Fixes: babbe170e0 ("sched/uclamp: Update CPU's refcount on TG's clamp changes")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Patrick Bellasi <patrick.bellasi@matbug.net>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Ben Segall <bsegall@google.com>
Link: https://lkml.kernel.org/r/20191105112212.596-1-qais.yousef@arm.com
* for-next/elf-hwcap-docs:
: Update the arm64 ELF HWCAP documentation
docs/arm64: cpu-feature-registers: Rewrite bitfields that don't follow [e, s]
docs/arm64: cpu-feature-registers: Documents missing visible fields
docs/arm64: elf_hwcaps: Document HWCAP_SB
docs/arm64: elf_hwcaps: sort the HWCAP{, 2} documentation by ascending value
* for-next/smccc-conduit-cleanup:
: SMC calling convention conduit clean-up
firmware: arm_sdei: use common SMCCC_CONDUIT_*
firmware/psci: use common SMCCC_CONDUIT_*
arm: spectre-v2: use arm_smccc_1_1_get_conduit()
arm64: errata: use arm_smccc_1_1_get_conduit()
arm/arm64: smccc/psci: add arm_smccc_1_1_get_conduit()
* for-next/zone-dma:
: Reintroduction of ZONE_DMA for Raspberry Pi 4 support
arm64: mm: reserve CMA and crashkernel in ZONE_DMA32
dma/direct: turn ARCH_ZONE_DMA_BITS into a variable
arm64: Make arm64_dma32_phys_limit static
arm64: mm: Fix unused variable warning in zone_sizes_init
mm: refresh ZONE_DMA and ZONE_DMA32 comments in 'enum zone_type'
arm64: use both ZONE_DMA and ZONE_DMA32
arm64: rename variables used to calculate ZONE_DMA32's size
arm64: mm: use arm64_dma_phys_limit instead of calling max_zone_dma_phys()
* for-next/relax-icc_pmr_el1-sync:
: Relax ICC_PMR_EL1 (GICv3) accesses when ICC_CTLR_EL1.PMHE is clear
arm64: Document ICC_CTLR_EL3.PMHE setting requirements
arm64: Relax ICC_PMR_EL1 accesses when ICC_CTLR_EL1.PMHE is clear
* for-next/double-page-fault:
: Avoid a double page fault in __copy_from_user_inatomic() if hw does not support auto Access Flag
mm: fix double page fault on arm64 if PTE_AF is cleared
x86/mm: implement arch_faults_on_old_pte() stub on x86
arm64: mm: implement arch_faults_on_old_pte() on arm64
arm64: cpufeature: introduce helper cpu_has_hw_af()
* for-next/misc:
: Various fixes and clean-ups
arm64: kpti: Add NVIDIA's Carmel core to the KPTI whitelist
arm64: mm: Remove MAX_USER_VA_BITS definition
arm64: mm: simplify the page end calculation in __create_pgd_mapping()
arm64: print additional fault message when executing non-exec memory
arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill()
arm64: pgtable: Correct typo in comment
arm64: docs: cpu-feature-registers: Document ID_AA64PFR1_EL1
arm64: cpufeature: Fix typos in comment
arm64/mm: Poison initmem while freeing with free_reserved_area()
arm64: use generic free_initrd_mem()
arm64: simplify syscall wrapper ifdeffery
* for-next/kselftest-arm64-signal:
: arm64-specific kselftest support with signal-related test-cases
kselftest: arm64: fake_sigreturn_misaligned_sp
kselftest: arm64: fake_sigreturn_bad_size
kselftest: arm64: fake_sigreturn_duplicated_fpsimd
kselftest: arm64: fake_sigreturn_missing_fpsimd
kselftest: arm64: fake_sigreturn_bad_size_for_magic0
kselftest: arm64: fake_sigreturn_bad_magic
kselftest: arm64: add helper get_current_context
kselftest: arm64: extend test_init functionalities
kselftest: arm64: mangle_pstate_invalid_mode_el[123][ht]
kselftest: arm64: mangle_pstate_invalid_daif_bits
kselftest: arm64: mangle_pstate_invalid_compat_toggle and common utils
kselftest: arm64: extend toplevel skeleton Makefile
* for-next/kaslr-diagnostics:
: Provide diagnostics on boot for KASLR
arm64: kaslr: Check command line before looking for a seed
arm64: kaslr: Announce KASLR status on boot
Create a new function called lookup_rec() from the functionality of
ftrace_location_range(). The difference between lookup_rec() is that it
returns the record that it finds, where as ftrace_location_range() returns
only if it found a match or not.
The lookup_rec() is static, and can be used for new functionality where
ftrace needs to find a record of a specific address.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Most of the functionality of __ftrace_hash_move() can be reused, but not all
of it. That is, __ftrace_hash_move() is used to simply make a new hash from
an existing one, using the same size as the original. Creating a dup_hash(),
where we can specify a new size will be useful when we want to create a hash
with a default size, or simply copy the old one.
Signed-off-by: Steven Rostedt (VMWare) <rostedt@goodmis.org>
This patch adds array support to btf_struct_access().
It supports array of int, array of struct and multidimensional
array.
It also allows using u8[] as a scratch space. For example,
it allows access the "char cb[48]" with size larger than
the array's element "char". Another potential use case is
"u64 icsk_ca_priv[]" in the tcp congestion control.
btf_resolve_size() is added to resolve the size of any type.
It will follow the modifier if there is any. Please
see the function comment for details.
This patch also adds the "off < moff" check at the beginning
of the for loop. It is to reject cases when "off" is pointing
to a "hole" in a struct.
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191107180903.4097702-1-kafai@fb.com
We can just call dma_free_contiguous directly instead of wrapping it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Filippov <jcmvbkbc@gmail.com>
It's not necessary to adjust the task state and revisit the state
of source and destination cgroups if the cgroups are not in freeze
state and the task itself is not frozen.
And in this scenario, it wakes up the task who's not supposed to be
ready to run.
Don't do the unnecessary task state adjustment can help stop waking
up the task without a reason.
Signed-off-by: Honglei Wang <honglei.wang@oracle.com>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Initialize the cpufreq governors earlier to allow for earlier
performance control during the boot process.
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Reviewed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/b98eae9b44eb2f034d7f5d12a161f5f831be1eb7.1571656015.git.amit.kucheria@linaro.org
In the bpf interpreter mode, bpf_probe_read_kernel is used to read
from PTR_TO_BTF_ID's kernel object. It currently missed considering
the insn->off. This patch fixes it.
Fixes: 2a02759ef5 ("bpf: Add support for BTF pointers to interpreter")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191107014640.384083-1-kafai@fb.com
We need to drop the bpf_devs_lock on error before returning.
Fixes: 9fd7c55591 ("bpf: offload: aggregate offloads per-device")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Link: https://lore.kernel.org/bpf/20191104091536.GB31509@mwanda
cgroup->bstat_pending is used to determine the base stat delta to
propagate to the parent. While correct, this is different from how
percpu delta is determined for no good reason and the inconsistency
makes the code more difficult to understand.
This patch makes parent propagation delta calculation use the same
method as percpu to global propagation.
* cgroup_base_stat_accumulate() is renamed to cgroup_base_stat_add()
and cgroup_base_stat_sub() is added.
* percpu propagation calculation is updated to use the above helpers.
* cgroup->bstat_pending is replaced with cgroup->last_bstat and
updated to use the same calculation as percpu propagation.
Signed-off-by: Tejun Heo <tj@kernel.org>
When using patchable-function-entry, the compiler will record the
callsites into a section named "__patchable_function_entries" rather
than "__mcount_loc". Let's abstract this difference behind a new
FTRACE_CALLSITE_SECTION, so that architectures don't have to handle this
explicitly (e.g. with custom module linker scripts).
As parisc currently handles this explicitly, it is fixed up accordingly,
with its custom linker script removed. Since FTRACE_CALLSITE_SECTION is
only defined when DYNAMIC_FTRACE is selected, the parisc module loading
code is updated to only use the definition in that case. When
DYNAMIC_FTRACE is not selected, modules shouldn't have this section, so
this removes some redundant work in that case.
To make sure that this is keep up-to-date for modules and the main
kernel, a comment is added to vmlinux.lds.h, with the existing ifdeffery
simplified for legibility.
I built parisc generic-{32,64}bit_defconfig with DYNAMIC_FTRACE enabled,
and verified that the section made it into the .ko files for modules.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Helge Deller <deller@gmx.de>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Tested-by: Sven Schnelle <svens@stackframe.org>
Tested-by: Torsten Duwe <duwe@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James E.J. Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: linux-parisc@vger.kernel.org
Architectures may need to perform special initialization of ftrace
callsites, and today they do so by special-casing ftrace_make_nop() when
the expected branch address is MCOUNT_ADDR. In some cases (e.g. for
patchable-function-entry), we don't have an mcount-like symbol and don't
want a synthetic MCOUNT_ADDR, but we may need to perform some
initialization of callsites.
To make it possible to separate initialization from runtime
modification, and to handle cases without an mcount-like symbol, this
patch adds an optional ftrace_init_nop() function that architectures can
implement, which does not pass a branch address.
Where an architecture does not provide ftrace_init_nop(), we will fall
back to the existing behaviour of calling ftrace_make_nop() with
MCOUNT_ADDR.
At the same time, ftrace_code_disable() is renamed to
ftrace_nop_initialize() to make it clearer that it is intended to
intialize a callsite into a disabled state, and is not for disabling a
callsite that has been runtime enabled. The kerneldoc description of rec
arguments is updated to cover non-mcount callsites.
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Reviewed-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Torsten Duwe <duwe@suse.de>
Tested-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Tested-by: Sven Schnelle <svens@stackframe.org>
Tested-by: Torsten Duwe <duwe@suse.de>
Cc: Ingo Molnar <mingo@redhat.com>
Daniel Borkmann says:
====================
pull-request: bpf 2019-11-02
The following pull-request contains BPF updates for your *net* tree.
We've added 6 non-merge commits during the last 6 day(s) which contain
a total of 8 files changed, 35 insertions(+), 9 deletions(-).
The main changes are:
1) Fix ppc BPF JIT's tail call implementation by performing a second pass
to gather a stable JIT context before opcode emission, from Eric Dumazet.
2) Fix build of BPF samples sys_perf_event_open() usage to compiled out
unavailable test_attr__{enabled,open} checks. Also fix potential overflows
in bpf_map_{area_alloc,charge_init} on 32 bit archs, from Björn Töpel.
3) Fix narrow loads of bpf_sysctl context fields with offset > 0 on big endian
archs like s390x and also improve the test coverage, from Ilya Leoshkevich.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXcGMxwAKCRCRxhvAZXjc
otEzAP9lHvP97TtRG9gP6dj6YovZ5Djdo3IscmkTqy5Nt8sVNQD+NWg1LZnSMFdJ
ExETgRVlsjF8q2sblswtn/8Ab53O6AM=
=RVGl
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2019-11-05' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull clone3 stack argument update from Christian Brauner:
"This changes clone3() to do basic stack validation and to set up the
stack depending on whether or not it is growing up or down.
With clone3() the expectation is now very simply that the .stack
argument points to the lowest address of the stack and that
.stack_size specifies the initial stack size. This is diferent from
legacy clone() where the "stack" argument had to point to the lowest
or highest address of the stack depending on the architecture.
clone3() was released with 5.3. Currently, it is not documented and
very unclear to userspace how the stack and stack_size argument have
to be passed. After talking to glibc folks we concluded that changing
clone3() to determine stack direction and doing basic validation is
the right course of action.
Note, this is a potentially user visible change. In the very unlikely
case, that it breaks someone's use-case we will revert. (And then e.g.
place the new behavior under an appropriate flag.)
Note that passing an empty stack will continue working just as before.
Breaking someone's use-case is very unlikely. Neither glibc nor musl
currently expose a wrapper for clone3(). There is currently also no
real motivation for anyone to use clone3() directly. First, because
using clone{3}() with stacks requires some assembly (see glibc and
musl). Second, because it does not provide features that legacy
clone() doesn't. New features for clone3() will first happen in v5.5
which is why v5.4 is still a good time to try and make that change now
and backport it to v5.3.
I did a codesearch on https://codesearch.debian.net, github, and
gitlab and could not find any software currently relying directly on
clone3(). I expect this to change once we land CLONE_CLEAR_SIGHAND
which was a request coming from glibc at which point they'll likely
start using it"
* tag 'for-linus-2019-11-05' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
clone3: validate stack arguments
Validate the stack arguments and setup the stack depening on whether or not
it is growing down or up.
Legacy clone() required userspace to know in which direction the stack is
growing and pass down the stack pointer appropriately. To make things more
confusing microblaze uses a variant of the clone() syscall selected by
CONFIG_CLONE_BACKWARDS3 that takes an additional stack_size argument.
IA64 has a separate clone2() syscall which also takes an additional
stack_size argument. Finally, parisc has a stack that is growing upwards.
Userspace therefore has a lot nasty code like the following:
#define __STACK_SIZE (8 * 1024 * 1024)
pid_t sys_clone(int (*fn)(void *), void *arg, int flags, int *pidfd)
{
pid_t ret;
void *stack;
stack = malloc(__STACK_SIZE);
if (!stack)
return -ENOMEM;
#ifdef __ia64__
ret = __clone2(fn, stack, __STACK_SIZE, flags | SIGCHLD, arg, pidfd);
#elif defined(__parisc__) /* stack grows up */
ret = clone(fn, stack, flags | SIGCHLD, arg, pidfd);
#else
ret = clone(fn, stack + __STACK_SIZE, flags | SIGCHLD, arg, pidfd);
#endif
return ret;
}
or even crazier variants such as [3].
With clone3() we have the ability to validate the stack. We can check that
when stack_size is passed, the stack pointer is valid and the other way
around. We can also check that the memory area userspace gave us is fine to
use via access_ok(). Furthermore, we probably should not require
userspace to know in which direction the stack is growing. It is easy
for us to do this in the kernel and I couldn't find the original
reasoning behind exposing this detail to userspace.
/* Intentional user visible API change */
clone3() was released with 5.3. Currently, it is not documented and very
unclear to userspace how the stack and stack_size argument have to be
passed. After talking to glibc folks we concluded that trying to change
clone3() to setup the stack instead of requiring userspace to do this is
the right course of action.
Note, that this is an explicit change in user visible behavior we introduce
with this patch. If it breaks someone's use-case we will revert! (And then
e.g. place the new behavior under an appropriate flag.)
Breaking someone's use-case is very unlikely though. First, neither glibc
nor musl currently expose a wrapper for clone3(). Second, there is no real
motivation for anyone to use clone3() directly since it does not provide
features that legacy clone doesn't. New features for clone3() will first
happen in v5.5 which is why v5.4 is still a good time to try and make that
change now and backport it to v5.3. Searches on [4] did not reveal any
packages calling clone3().
[1]: https://lore.kernel.org/r/CAG48ez3q=BeNcuVTKBN79kJui4vC6nw0Bfq6xc-i0neheT17TA@mail.gmail.com
[2]: https://lore.kernel.org/r/20191028172143.4vnnjpdljfnexaq5@wittgenstein
[3]: 5238e95759/src/basic/raw-clone.h (L31)
[4]: https://codesearch.debian.net
Fixes: 7f192e3cd3 ("fork: add clone3")
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-api@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # 5.3
Cc: GNU C Library <libc-alpha@sourceware.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Aleksa Sarai <cyphar@cyphar.com>
Link: https://lore.kernel.org/r/20191031113608.20713-1-christian.brauner@ubuntu.com
A recent commit changed a parameter of __irq_domain_alloc_fwnode(), but
did not update the documentation comment. Fix it up.
Fixes: b977fcf477 ("irqdomain/debugfs: Use PAs to generate fwnode names")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1571476047-29463-1-git-send-email-wang.yi59@zte.com.cn
The update of the VDSO data is depending on __arch_use_vsyscall() returning
True. This is a leftover from the attempt to map the features of various
architectures 1:1 into generic code.
The usage of __arch_use_vsyscall() in the actual vsyscall implementations
got dropped and replaced by the requirement for the architecture code to
return U64_MAX if the global clocksource is not usable in the VDSO.
But the __arch_use_vsyscall() check in the update code stayed which causes
the VDSO data to be stale or invalid when an architecture actually
implements that function and returns False when the current clocksource is
not usable in the VDSO.
As a consequence the VDSO implementations of clock_getres(), time(),
clock_gettime(CLOCK_.*_COARSE) operate on invalid data and return bogus
information.
Remove the __arch_use_vsyscall() check from the VDSO update function and
update the VDSO data unconditionally.
[ tglx: Massaged changelog and removed the now useless implementations in
asm-generic/ARM64/MIPS ]
Fixes: 44f57d788e ("timekeeping: Provide a generic update_vsyscall() implementation")
Signed-off-by: Huacai Chen <chenhc@lemote.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Paul Burton <paul.burton@mips.com>
Cc: linux-mips@vger.kernel.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1571887709-11447-1-git-send-email-chenhc@lemote.com
When doing cat /proc/<PID>/stack, the output is missing the first entry.
When the current code walks the stack starting in stack_trace_save_tsk,
it skips all scheduler functions (that's OK) plus one more function. But
this one function should be skipped only for the 'current' task as it is
stack_trace_save_tsk proper.
The original code (before the common infrastructure) skipped one
function only for the 'current' task -- see save_stack_trace_tsk before
3599fe12a1. So do so also in the new infrastructure now.
Fixes: 214d8ca6ee ("stacktrace: Provide common infrastructure")
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Michal Suchanek <msuchanek@suse.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Link: https://lkml.kernel.org/r/20191030072545.19462-1-jslaby@suse.cz
Livepatch uses ftrace for redirection to new patched functions. It means
that if ftrace is disabled, all live patched functions are disabled as
well. Toggling global 'ftrace_enabled' sysctl thus affect it directly.
It is not a problem per se, because only administrator can set sysctl
values, but it still may be surprising.
Introduce PERMANENT ftrace_ops flag to amend this. If the
FTRACE_OPS_FL_PERMANENT is set on any ftrace ops, the tracing cannot be
disabled by disabling ftrace_enabled. Equally, a callback with the flag
set cannot be registered if ftrace_enabled is disabled.
Link: http://lkml.kernel.org/r/20191016113316.13415-2-mbenes@suse.cz
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
A kernel module may need to check the value of the "mitigations=" kernel
command line parameter as part of its setup when the module needs
to perform software mitigations for a CPU flaw.
Uninline and export the helper functions surrounding the cpu_mitigations
enum to allow for their usage from a module.
Lastly, privatize the enum and cpu_mitigations variable since the value of
cpu_mitigations can be checked with the exported helper functions.
Signed-off-by: Tyler Hicks <tyhicks@canonical.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2019-11-02
The following pull-request contains BPF updates for your *net-next* tree.
We've added 30 non-merge commits during the last 7 day(s) which contain
a total of 41 files changed, 1864 insertions(+), 474 deletions(-).
The main changes are:
1) Fix long standing user vs kernel access issue by introducing
bpf_probe_read_user() and bpf_probe_read_kernel() helpers, from Daniel.
2) Accelerated xskmap lookup, from Björn and Maciej.
3) Support for automatic map pinning in libbpf, from Toke.
4) Cleanup of BTF-enabled raw tracepoints, from Alexei.
5) Various fixes to libbpf and selftests.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The only slightly tricky merge conflict was the netdevsim because the
mutex locking fix overlapped a lot of driver reload reorganization.
The rest were (relatively) trivial in nature.
Signed-off-by: David S. Miller <davem@davemloft.net>
Commit 2a02759ef5 ("bpf: Add support for BTF pointers to interpreter")
explicitly states that the pointer to BTF object is a pointer to a kernel
object or NULL. Therefore we should also switch to using the strict kernel
probe helper which is restricted to kernel addresses only when architectures
have non-overlapping address spaces.
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/d2b90827837685424a4b8008dfe0460558abfada.1572649915.git.daniel@iogearbox.net
The current bpf_probe_read() and bpf_probe_read_str() helpers are broken
in that they assume they can be used for probing memory access for kernel
space addresses /as well as/ user space addresses.
However, plain use of probe_kernel_read() for both cases will attempt to
always access kernel space address space given access is performed under
KERNEL_DS and some archs in-fact have overlapping address spaces where a
kernel pointer and user pointer would have the /same/ address value and
therefore accessing application memory via bpf_probe_read{,_str}() would
read garbage values.
Lets fix BPF side by making use of recently added 3d7081822f ("uaccess:
Add non-pagefault user-space read functions"). Unfortunately, the only way
to fix this status quo is to add dedicated bpf_probe_read_{user,kernel}()
and bpf_probe_read_{user,kernel}_str() helpers. The bpf_probe_read{,_str}()
helpers are kept as-is to retain their current behavior.
The two *_user() variants attempt the access always under USER_DS set, the
two *_kernel() variants will -EFAULT when accessing user memory if the
underlying architecture has non-overlapping address ranges, also avoiding
throwing the kernel warning via 00c42373d3 ("x86-64: add warning for
non-canonical user access address dereferences").
Fixes: a5e8c07059 ("bpf: add bpf_probe_read_str helper")
Fixes: 2541517c32 ("tracing, perf: Implement BPF programs attached to kprobes")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/796ee46e948bc808d54891a1108435f8652c6ca4.1572649915.git.daniel@iogearbox.net
Convert the bpf_probe_write_user() helper to probe_user_write() such that
writes are not attempted under KERNEL_DS anymore which is buggy as kernel
and user space pointers can have overlapping addresses. Also, given we have
the access_ok() check inside probe_user_write(), the helper doesn't need
to do it twice.
Fixes: 96ae522795 ("bpf: Add bpf_probe_write_user BPF helper to be called in tracers")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/841c461781874c07a0ee404a454c3bc0459eed30.1572649915.git.daniel@iogearbox.net
Pull networking fixes from David Miller:
1) Fix free/alloc races in batmanadv, from Sven Eckelmann.
2) Several leaks and other fixes in kTLS support of mlx5 driver, from
Tariq Toukan.
3) BPF devmap_hash cost calculation can overflow on 32-bit, from Toke
Høiland-Jørgensen.
4) Add an r8152 device ID, from Kazutoshi Noguchi.
5) Missing include in ipv6's addrconf.c, from Ben Dooks.
6) Use siphash in flow dissector, from Eric Dumazet. Attackers can
easily infer the 32-bit secret otherwise etc.
7) Several netdevice nesting depth fixes from Taehee Yoo.
8) Fix several KCSAN reported errors, from Eric Dumazet. For example,
when doing lockless skb_queue_empty() checks, and accessing
sk_napi_id/sk_incoming_cpu lockless as well.
9) Fix jumbo packet handling in RXRPC, from David Howells.
10) Bump SOMAXCONN and tcp_max_syn_backlog values, from Eric Dumazet.
11) Fix DMA synchronization in gve driver, from Yangchun Fu.
12) Several bpf offload fixes, from Jakub Kicinski.
13) Fix sk_page_frag() recursion during memory reclaim, from Tejun Heo.
14) Fix ping latency during high traffic rates in hisilicon driver, from
Jiangfent Xiao.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
net: fix installing orphaned programs
net: cls_bpf: fix NULL deref on offload filter removal
selftests: bpf: Skip write only files in debugfs
selftests: net: reuseport_dualstack: fix uninitalized parameter
r8169: fix wrong PHY ID issue with RTL8168dp
net: dsa: bcm_sf2: Fix IMP setup for port different than 8
net: phylink: Fix phylink_dbg() macro
gve: Fixes DMA synchronization.
inet: stop leaking jiffies on the wire
ixgbe: Remove duplicate clear_bit() call
Documentation: networking: device drivers: Remove stray asterisks
e1000: fix memory leaks
i40e: Fix receive buffer starvation for AF_XDP
igb: Fix constant media auto sense switching when no cable is connected
net: ethernet: arc: add the missed clk_disable_unprepare
igb: Enable media autosense for the i350.
igb/igc: Don't warn on fatal read failures when the device is removed
tcp: increase tcp_max_syn_backlog max value
net: increase SOMAXCONN to 4096
netdevsim: Fix use-after-free during device dismantle
...
In this commit the XSKMAP entry lookup function used by the XDP
redirect code is moved from the xskmap.c file to the xdp_sock.h
header, so the lookup can be inlined from, e.g., the
bpf_xdp_redirect_map() function.
Further the __xsk_map_redirect() and __xsk_map_flush() is moved to the
xsk.c, which lets the compiler inline the xsk_rcv() and xsk_flush()
functions.
Finally, all the XDP socket functions were moved from linux/bpf.h to
net/xdp_sock.h, where most of the XDP sockets functions are anyway.
This yields a ~2% performance boost for the xdpsock "rx_drop"
scenario.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191101110346.15004-4-bjorn.topel@gmail.com
Inline the xsk_map_lookup_elem() via implementing the map_gen_lookup()
callback. This results in emitting the bpf instructions in place of
bpf_map_lookup_elem() helper call and better performance of bpf
programs.
Signed-off-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/20191101110346.15004-3-bjorn.topel@gmail.com
Prior this commit, the array storing XDP socket instances were stored
in a separate allocated array of the XSKMAP. Now, we store the sockets
as a flexible array member in a similar fashion as the arraymap. Doing
so, we do less pointer chasing in the lookup.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Link: https://lore.kernel.org/bpf/20191101110346.15004-2-bjorn.topel@gmail.com
Fix two pointer-to-int-cast warnings when compiling for the 32-bit parisc
platform:
kernel/kexec_file.c: In function ‘crash_prepare_elf64_headers’:
kernel/kexec_file.c:1307:19: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
phdr->p_vaddr = (Elf64_Addr)_text;
^
kernel/kexec_file.c:1324:19: warning: cast from pointer to integer of different size [-Wpointer-to-int-cast]
phdr->p_vaddr = (unsigned long long) __va(mstart);
^
Signed-off-by: Helge Deller <deller@gmx.de>
Pull scheduler fixes from Ingo Molnar:
"Fix two scheduler topology bugs/oversights on Juno r0 2+4 big.LITTLE
systems"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/topology: Allow sched_asym_cpucapacity to be disabled
sched/topology: Don't try to build empty sched domains
The atomic replace runs pre/post (un)install callbacks only from the new
livepatch. There are several reasons for this:
+ Simplicity: clear ordering of operations, no interactions between
old and new callbacks.
+ Reliability: only new livepatch knows what changes can already be made
by older livepatches and how to take over the state.
+ Testing: the atomic replace can be properly tested only when a newer
livepatch is available. It might be too late to fix unwanted effect
of callbacks from older livepatches.
It might happen that an older change is not enough and the same system
state has to be modified another way. Different changes need to get
distinguished by a version number added to struct klp_state.
The version can also be used to prevent loading incompatible livepatches.
The check is done when the livepatch is enabled. The rules are:
+ Any completely new system state modification is allowed.
+ System state modifications with the same or higher version are allowed
for already modified system states.
+ Cumulative livepatches must handle all system state modifications from
already installed livepatches.
+ Non-cumulative livepatches are allowed to touch already modified
system states.
Link: http://lkml.kernel.org/r/20191030154313.13263-4-pmladek@suse.com
To: Jiri Kosina <jikos@kernel.org>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: live-patching@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
This is another step how to help maintaining more livepatches.
One big help was the atomic replace and cumulative livepatches. These
livepatches replace the already installed ones. Therefore it should
be enough when each cumulative livepatch is consistent.
The problems might come with shadow variables and callbacks. They might
change the system behavior or state so that it is no longer safe to
go back and use an older livepatch or the original kernel code. Also,
a new livepatch must be able to detect changes which were made by
the already installed livepatches.
This is where the livepatch system state tracking gets useful. It
allows to:
- find whether a system state has already been modified by
previous livepatches
- store data needed to manipulate and restore the system state
The information about the manipulated system states is stored in an
array of struct klp_state. It can be searched by two new functions
klp_get_state() and klp_get_prev_state().
The dependencies are going to be solved by a version field added later.
The only important information is that it will be allowed to modify
the same state by more non-cumulative livepatches. It is similar
to allowing to modify the same function several times. The livepatch
author is responsible for preventing incompatible changes.
Link: http://lkml.kernel.org/r/20191030154313.13263-3-pmladek@suse.com
To: Jiri Kosina <jikos@kernel.org>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: live-patching@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Pre/post (un)patch callbacks might manipulate the system state. Cumulative
livepatches might need to take over the changes made by the replaced
ones. For this they might need to access some data stored or referenced
by the old livepatches.
Therefore the replaced livepatches have to stay around until post_patch()
callback is called. It is achieved by calling the free functions later.
It is the same location where disabled livepatches have already been
freed.
Link: http://lkml.kernel.org/r/20191030154313.13263-2-pmladek@suse.com
To: Jiri Kosina <jikos@kernel.org>
Cc: Kamalesh Babulal <kamalesh@linux.vnet.ibm.com>
Cc: Nicolai Stange <nstange@suse.de>
Cc: live-patching@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Acked-by: Miroslav Benes <mbenes@suse.cz>
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Some architectures, notably ARM, are interested in tweaking this
depending on their runtime DMA addressing limitations.
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
The functions bpf_map_area_alloc() and bpf_map_charge_init() prior
this commit passed the size parameter as size_t. In this commit this
is changed to u64.
All users of these functions avoid size_t overflows on 32-bit systems,
by explicitly using u64 when calculating the allocation size and
memory charge cost. However, since the result was narrowed by the
size_t when passing size and cost to the functions, the overflow
handling was in vain.
Instead of changing all call sites to size_t and handle overflow at
the call site, the parameter is changed to u64 and checked in the
functions above.
Fixes: d407bd25a2 ("bpf: don't trigger OOM killer under pressure with map alloc")
Fixes: c85d69135a ("bpf: move memory size checks to bpf_map_charge_init()")
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Link: https://lore.kernel.org/bpf/20191029154307.23053-1-bjorn.topel@gmail.com
Add a wakeup call for a case whereby the caller already has the waitqueue
spinlock held. This can be used by pipes to alter the ring buffer indices
and issue a wakeup under the same spinlock.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
The bpf program type raw_tp together with 'expected_attach_type'
was the most appropriate api to indicate BTF-enabled raw_tp programs.
But during development it became apparent that 'expected_attach_type'
cannot be used and new 'attach_btf_id' field had to be introduced.
Which means that the information is duplicated in two fields where
one of them is ignored.
Clean it up by introducing new program type where both
'expected_attach_type' and 'attach_btf_id' fields have
specific meaning.
In the future 'expected_attach_type' will be extended
with other attach points that have similar semantics to raw_tp.
This patch is replacing BTF-enabled BPF_PROG_TYPE_RAW_TRACEPOINT with
prog_type = BPF_RPOG_TYPE_TRACING
expected_attach_type = BPF_TRACE_RAW_TP
attach_btf_id = btf_id of raw tracepoint inside the kernel
Future patches will add
expected_attach_type = BPF_TRACE_FENTRY or BPF_TRACE_FEXIT
where programs have the same input context and the same helpers,
but different attach points.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191030223212.953010-2-ast@kernel.org
Pull RCU and LKMM changes from Paul E. McKenney:
- Documentation updates.
- Miscellaneous fixes.
- Dynamic tick (nohz) updates, perhaps most notably changes to
force the tick on when needed due to lengthy in-kernel execution
on CPUs on which RCU is waiting.
- Replace rcu_swap_protected() with rcu_prepace_pointer().
- Torture-test updates.
- Linux-kernel memory consistency model updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jiri reported crash when JIT is on, but net.core.bpf_jit_kallsyms is off.
bpf_prog_kallsyms_find() was skipping addr->bpf_prog resolution
logic in oops and stack traces. That's incorrect.
It should only skip addr->name resolution for 'cat /proc/kallsyms'.
That's what bpf_jit_kallsyms and bpf_jit_harden protect.
Fixes: 3dec541b2e ("bpf: Add support for BTF pointers to x86 JIT")
Reported-by: Jiri Olsa <jolsa@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191030233019.1187404-1-ast@kernel.org
"ctx:file_pos sysctl:read read ok narrow" works on s390 by accident: it
reads the wrong byte, which happens to have the expected value of 0.
Improve the test by seeking to the 4th byte and expecting 4 instead of
0.
This makes the latent problem apparent: the test attempts to read the
first byte of bpf_sysctl.file_pos, assuming this is the least-significant
byte, which is not the case on big-endian machines: a non-zero offset is
needed.
The point of the test is to verify narrow loads, so we cannot cheat our
way out by simply using BPF_W. The existence of the test means that such
loads have to be supported, most likely because llvm can generate them.
Fix the test by adding a big-endian variant, which uses an offset to
access the least-significant byte of bpf_sysctl.file_pos.
This reveals the final problem: verifier rejects accesses to bpf_sysctl
fields with offset > 0. Such accesses are already allowed for a wide
range of structs: __sk_buff, bpf_sock_addr and sk_msg_md to name a few.
Extend this support to bpf_sysctl by using bpf_ctx_range instead of
offsetof when matching field offsets.
Fixes: 7b146cebe3 ("bpf: Sysctl hook")
Fixes: e1550bfe0d ("bpf: Add file_pos field to bpf_sysctl ctx")
Fixes: 9a1027e525 ("selftests/bpf: Test file_pos field in bpf_sysctl ctx")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrey Ignatov <rdna@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191028122902.9763-1-iii@linux.ibm.com
These parameters are only referenced by __init routine calls during
early boot so they should be marked as __initdata and __initconst
accordingly.
Signed-off-by: Shyam Saini <mayhs11saini@gmail.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
debug_dma_dump_mappings() can take a lot of cpu cycles :
lpk43:/# time wc -l /sys/kernel/debug/dma-api/dump
163435 /sys/kernel/debug/dma-api/dump
real 0m0.463s
user 0m0.003s
sys 0m0.459s
Let's add a cond_resched() to avoid holding cpu for too long.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Corentin Labbe <clabbe@baylibre.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Daniele reported that issue previously fixed in c41f9ea998
("drivers: dma-coherent: Account dma_pfn_offset when used with device
tree") reappear shortly after 43fc509c3e ("dma-coherent: introduce
interface for default DMA pool") where fix was accidentally dropped.
Lets put fix back in place and respect dma-ranges for reserved memory.
Fixes: 43fc509c3e ("dma-coherent: introduce interface for default DMA pool")
Reported-by: Daniele Alessandrelli <daniele.alessandrelli@gmail.com>
Tested-by: Daniele Alessandrelli <daniele.alessandrelli@gmail.com>
Tested-by: Alexandre Torgue <alexandre.torgue@st.com>
Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
This commit replaces the use of rcu_swap_protected() with the more
intuitively appealing rcu_replace_pointer() as a step towards removing
rcu_swap_protected().
Link: https://lore.kernel.org/lkml/CAHk-=wiAsJLw1egFEE=Z7-GGtM6wcvtyytXZA1+BHqta4gg6Hw@mail.gmail.com/
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
[ paulmck: From rcu_replace() to rcu_replace_pointer() per Ingo Molnar. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: <netdev@vger.kernel.org>
Cc: <bpf@vger.kernel.org>
New tools bring new warnings, and with v5.3 comes:
kernel/rcu/srcutree.c: warning: 'levelspread[<U aa0>]' may be used uninitialized in this function [-Wuninitialized]: => 121:34
This commit suppresses this warning by initializing the full array
to INT_MIN, which will result in failures should any out-of-bounds
references appear.
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Reported-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
We never set this to false. This probably doesn't affect most people's
runtime because GCC will automatically initialize it to false at certain
common optimization levels. But that behavior is related to a bug in
GCC and obviously should not be relied on.
Fixes: 5d6742b377 ("rcu/nocb: Use rcu_segcblist for no-CBs CPUs")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The RCU-specific resched_cpu() function sends a resched IPI to the
specified CPU, which can be used to force the tick on for a given
nohz_full CPU. This is needed when this nohz_full CPU is looping in the
kernel while blocking the current grace period. However, for the tick
to actually be forced on in all cases, that CPU's rcu_data structure's
->rcu_urgent_qs flag must be set beforehand. This commit therefore
causes rcu_implicit_dynticks_qs() to set this flag prior to invoking
resched_cpu() on a holdout nohz_full CPU.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Because list_for_each_entry_rcu() can now check for holding a
lock as well as for being in an RCU read-side critical section,
this commit replaces the workqueue_sysfs_unregister() function's
use of assert_rcu_or_wq_mutex() and list_for_each_entry_rcu() with
list_for_each_entry_rcu() augmented with a lockdep_is_held() optional
argument.
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
None of rcu_segcblist_set_len(), rcu_segcblist_add_len(), or
rcu_segcblist_xchg_len() are used outside of kernel/rcu/rcu_segcblist.c.
This commit therefore makes them static.
Fixes: eda669a6a2 ("rcu/nocb: Atomic ->len field in rcu_segcblist structure")
Signed-off-by: kbuild test robot <lkp@intel.com>
[ paulmck: "Fixes:" updated per Stephen Rothwell feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The return value of raw_tp programs is ignored by __bpf_trace_run()
that calls them. The verifier also allows any value to be returned.
For BTF-enabled raw_tp lets enforce 'return 0', so that return value
can be used for something in the future.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20191029032426.1206762-1-ast@kernel.org
This adds support for io-wq, a smaller and specialized thread pool
implementation. This is meant to replace workqueues for io_uring. Among
the reasons for this addition are:
- We can assign memory context smarter and more persistently if we
manage the life time of threads.
- We can drop various work-arounds we have in io_uring, like the
async_list.
- We can implement hashed work insertion, to manage concurrency of
buffered writes without needing a) an extra workqueue, or b)
needlessly making the concurrency of said workqueue very low
which hurts performance of multiple buffered file writers.
- We can implement cancel through signals, for cancelling
interruptible work like read/write (or send/recv) to/from sockets.
- We need the above cancel for being able to assign and use file tables
from a process.
- We can implement a more thorough cancel operation in general.
- We need it to move towards a syslet/threadlet model for even faster
async execution. For that we need to take ownership of the used
threads.
This list is just off the top of my head. Performance should be the
same, or better, at least that's what I've seen in my testing. io-wq
supports basic NUMA functionality, setting up a pool per node.
io-wq hooks up to the scheduler schedule in/out just like workqueue
and uses that to drive the need for more/less workers.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Add warning checks if mutex_trylock() or mutex_unlock() are used in
IRQ contexts, under CONFIG_DEBUG_MUTEXES=y.
While the mutex rules and semantics are explicitly documented, this allows
to expose any abusers and robustifies the whole thing.
While trylock and unlock are non-blocking, calling from IRQ context
is still forbidden (lock must be within the same context as unlock).
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Link: https://lkml.kernel.org/r/20191025033634.3330-1-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since the original comment, we have moved to do the task
reference counting explicitly along with wake_q_add_safe().
Drop the now incorrect comment.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dave@stgolabs.net
Link: https://lkml.kernel.org/r/20191023033450.6445-1-dave@stgolabs.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Kcpustat is not correctly supported on nohz_full CPUs. The tick doesn't
fire and the cputime therefore doesn't move forward. The issue has shown
up after the vanishing of the remaining 1Hz which has made the stall
visible.
We are solving that with checking the task running on a CPU through RCU
and reading its vtime delta that we add to the raw kcpustat values.
We make sure that we fetch a coherent raw-kcpustat/vtime-delta couple
sequence while checking that the CPU referred by the target vtime is the
correct one, under the locked vtime seqcount.
Only CPUTIME_SYSTEM is handled here as a start because it's the trivial
case. User and guest time will require more preparation work to
correctly handle niceness.
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Link: https://lkml.kernel.org/r/20191025020303.19342-1-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Standardize the naming on top of the vtime_accounting_enabled_*() base.
Also make it clear we are checking the vtime state of the
*current* CPU with this function. We'll need to add an API to check that
state on remote CPUs as well, so we must disambiguate the naming.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-9-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove the superfluous "is" in the middle of the name. We want to
standardize the naming so that it can be expanded through suffixes:
context_tracking_enabled()
context_tracking_enabled_cpu()
context_tracking_enabled_this_cpu()
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-6-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Record guest as a VTIME state instead of guessing it from VTIME_SYS and
PF_VCPU. This is going to simplify the cputime read side especially as
its state machine is going to further expand in order to fully support
kcpustat on nohz_full.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-4-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Record idle as a VTIME state instead of guessing it from VTIME_SYS and
is_idle_task(). This is going to simplify the cputime read side
especially as its state machine is going to further expand in order to
fully support kcpustat on nohz_full.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-3-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In order to compute the kcpustat delta on a nohz CPU, we'll need to
fetch the task running on that target. Checking that its vtime
state snapshot actually refers to the relevant target involves recording
that CPU under the seqcount locked on task switch.
This is a step toward making kcpustat moving forward on full nohz CPUs.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rafael J . Wysocki <rjw@rjwysocki.net>
Cc: Rik van Riel <riel@surriel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191016025700.31277-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The estimated utilization for a task:
util_est = max(util_avg, est.enqueue, est.ewma)
is defined based on:
- util_avg: the PELT defined utilization
- est.enqueued: the util_avg at the end of the last activation
- est.ewma: a exponential moving average on the est.enqueued samples
According to this definition, when a task suddenly changes its bandwidth
requirements from small to big, the EWMA will need to collect multiple
samples before converging up to track the new big utilization.
This slow convergence towards bigger utilization values is not
aligned to the default scheduler behavior, which is to optimize for
performance. Moreover, the est.ewma component fails to compensate for
temporarely utilization drops which spans just few est.enqueued samples.
To let util_est do a better job in the scenario depicted above, change
its definition by making util_est directly follow upward motion and
only decay the est.ewma on downward.
Signed-off-by: Patrick Bellasi <patrick.bellasi@matbug.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Douglas Raillard <douglas.raillard@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <qperret@google.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191023205630.14469-1-patrick.bellasi@matbug.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While the static key is correctly initialized as being disabled, it will
remain forever enabled once turned on. This means that if we start with an
asymmetric system and hotplug out enough CPUs to end up with an SMP system,
the static key will remain set - which is obviously wrong. We should detect
this and turn off things like misfit migration and capacity aware wakeups.
As Quentin pointed out, having separate root domains makes this slightly
trickier. We could have exclusive cpusets that create an SMP island - IOW,
the domains within this root domain will not see any asymmetry. This means
we can't just disable the key on domain destruction, we need to count how
many asymmetric root domains we have.
Consider the following example using Juno r0 which is 2+4 big.LITTLE, where
two identical cpusets are created: they both span both big and LITTLE CPUs:
asym0 asym1
[ ][ ]
L L B L L B
$ cgcreate -g cpuset:asym0
$ cgset -r cpuset.cpus=0,1,3 asym0
$ cgset -r cpuset.mems=0 asym0
$ cgset -r cpuset.cpu_exclusive=1 asym0
$ cgcreate -g cpuset:asym1
$ cgset -r cpuset.cpus=2,4,5 asym1
$ cgset -r cpuset.mems=0 asym1
$ cgset -r cpuset.cpu_exclusive=1 asym1
$ cgset -r cpuset.sched_load_balance=0 .
(the CPU numbering may look odd because on the Juno LITTLEs are CPUs 0,3-5
and bigs are CPUs 1-2)
If we make one of those SMP (IOW remove asymmetry) by e.g. hotplugging its
big core, we would end up with an SMP cpuset and an asymmetric cpuset - the
static key must remain set, because we still have one asymmetric root domain.
With the above example, this could be done with:
$ echo 0 > /sys/devices/system/cpu/cpu2/online
Which would result in:
asym0 asym1
[ ][ ]
L L B L L
When both SMP and asymmetric cpusets are present, all CPUs will observe
sched_asym_cpucapacity being set (it is system-wide), but not all CPUs
observe asymmetry in their sched domain hierarchy:
per_cpu(sd_asym_cpucapacity, <any CPU in asym0>) == <some SD at DIE level>
per_cpu(sd_asym_cpucapacity, <any CPU in asym1>) == NULL
Change the simple key enablement to an increment, and decrement the key
counter when destroying domains that cover asymmetric CPUs.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Dietmar.Eggemann@arm.com
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hannes@cmpxchg.org
Cc: lizefan@huawei.com
Cc: morten.rasmussen@arm.com
Cc: qperret@google.com
Cc: tj@kernel.org
Cc: vincent.guittot@linaro.org
Fixes: df054e8445 ("sched/topology: Add static_key for asymmetric CPU capacity optimizations")
Link: https://lkml.kernel.org/r/20191023153745.19515-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
include/linux/export.h has lots of code duplication between
EXPORT_SYMBOL and EXPORT_SYMBOL_NS.
To improve the maintainability and readability, unify the
implementation.
When the symbol has no namespace, pass the empty string "" to
the 'ns' parameter.
The drawback of this change is, it grows the code size.
When the symbol has no namespace, sym->namespace was previously
NULL, but it is now an empty string "". So, it increases 1 byte
for every no namespace EXPORT_SYMBOL.
A typical kernel configuration has 10K exported symbols, so it
increases 10KB in rough estimation.
I did not come up with a good idea to refactor it without increasing
the code size.
I am not sure how big a deal it is, but at least include/linux/export.h
looks nicer.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
[maennich: rebase on top of 3 fixes for the namespace feature]
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
If a nohz_full CPU is idle or executing in userspace, it makes good sense
to keep it out of RCU core processing. After all, the RCU grace-period
kthread can see its quiescent states and all of its callbacks are
offloaded, so there is nothing for RCU core processing to do.
However, if a nohz_full CPU is executing in kernel space, the RCU
grace-period kthread cannot do anything for it, so such a CPU must report
its own quiescent states. This commit therefore makes nohz_full CPUs
skip RCU core processing only if the scheduler-clock interrupt caught
them in idle or in userspace.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Commit 671a63517c ("rcu: Avoid unnecessary softirq when system
is idle") fixed a bug that could result in an indefinite number of
unnecessary invocations of the RCU_SOFTIRQ handler at the trailing edge
of a scheduler-clock interrupt. However, the fix introduced off-CPU
stores to ->core_needs_qs. These writes did not conflict with the
on-CPU stores because the CPU's leaf rcu_node structure's ->lock was
held across all such stores. However, the loads from ->core_needs_qs
were not promoted to READ_ONCE() and, worse yet, the code loading from
->core_needs_qs was written assuming that it was only ever updated by
the corresponding CPU. So operation has been robust, but only by luck.
This situation is therefore an accident waiting to happen.
This commit therefore takes a different approach. Instead of clearing
->core_needs_qs from the grace-period kthread's force-quiescent-state
processing, it modifies the rcu_pending() function to suppress the
rcu_sched_clock_irq() function's call to invoke_rcu_core() if there is no
grace period in progress. This avoids the infinite needless RCU_SOFTIRQ
handlers while still keeping all accesses to ->core_needs_qs local to
the corresponding CPU.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In some cases, tracing shows that need_heavy_qs is still set even though
urgent_qs was cleared upon reporting of a quiescent state. One such
case is when the softirq reports that a CPU has passed quiescent state.
Commit 671a63517c ("rcu: Avoid unnecessary softirq when system is
idle") fixed a bug where core_needs_qs was not being cleared. In order
to avoid running into similar situations with the urgent-grace-period
flags, this commit causes rcu_disable_urgency_upon_qs(), previously
rcu_disable_tick_upon_qs(), to clear the urgency hints, ->rcu_urgent_qs
and ->rcu_need_heavy_qs. Note that it is possible for CPUs to go
offline with these urgency hints still set. This is handled because
rcu_disable_urgency_upon_qs() is also invoked during the online process.
Because these hints can be cleared both by the corresponding CPU and by
the grace-period kthread, this commit also adds a number of READ_ONCE()
and WRITE_ONCE() calls.
Tested overnight with rcutorture running for 60 minutes on all
configurations of RCU.
Signed-off-by: "Joel Fernandes (Google)" <joel@joelfernandes.org>
[ paulmck: Clear urgency flags in rcu_disable_urgency_upon_qs(). ]
[ paulmck: Remove ->core_needs_qs from the set cleared at quiescent state. ]
[ paulmck: Make rcu_disable_urgency_upon_qs static per kbuild test robot. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
There is interrupt-exit code that forces on the tick for nohz_full CPUs
failing to respond to the current grace period in a timely fashion.
However, this code must compare ->dynticks_nmi_nesting to the value 2
in the interrupt-exit fastpath. This commit therefore moves this code
to the interrupt-entry fastpath, where a lighter-weight comparison to
zero may be used.
Reported-by: Joel Fernandes <joel@joelfernandes.org>
[ paulmck: Apply Joel Fernandes TICK_DEP_MASK_RCU->TICK_DEP_BIT_RCU fix. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
CPUs running for long time periods in the kernel in nohz_full mode
might leave the scheduling-clock interrupt disabled for then full
duration of their in-kernel execution. This can (among other things)
delay grace periods. This commit therefore forces the tick back on
for any nohz_full CPU that is failing to pass through a quiescent state
upon return from interrupt, which the resched_cpu() will induce.
Reported-by: Joel Fernandes <joel@joelfernandes.org>
[ paulmck: Clear ->rcu_forced_tick as reported by Joel Fernandes testing. ]
[ paulmck: Apply Joel Fernandes TICK_DEP_MASK_RCU->TICK_DEP_BIT_RCU fix. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently if sequences such as "\ehelp\r" are delivered to the console then
the h gets eaten by the escape handling code. Since pressing escape
becomes something of a nervous twitch for vi users (and that escape doesn't
have much effect at a shell prompt) it is more helpful to emit the 'h' than
the '\e'.
We don't simply choose to emit the final character for all escape sequences
since that will do odd things for unsupported escape sequences (in
other words we retain the existing behaviour once we see '\e[').
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191025073328.643-6-daniel.thompson@linaro.org
Currently if an escape timer is interrupted by a character from a
different input source then the new character is discarded and the
function returns '\e' (which will be discarded by the level above).
It is hard to see why this would ever be the desired behaviour.
Fix this to return the new character rather than the '\e'.
This is a bigger refactor than might be expected because the new
character needs to go through escape sequence detection.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191025073328.643-5-daniel.thompson@linaro.org
kdb_read() contains special case logic to force it exit after reading
a single character. We can remove all the special case logic by directly
calling the function to read a single character instead. This also
allows us to tidy up the function prototype which, because it now matches
getchar(), we can also rename in order to make its role clearer.
This does involve some extra code to handle btaprompt properly but we
don't mind the new lines of code here because the old code had some
interesting problems (bad newline handling, treating unexpected
characters like <cr>).
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191025073328.643-4-daniel.thompson@linaro.org
Currently kdb_read_get_key() contains complex control flow that, on
close inspection, turns out to be unnecessary. In particular:
1. It is impossible to enter the branch conditioned on (escape_delay == 1)
except when the loop enters with (escape_delay == 2) allowing us to
combine the branches.
2. Most of the code conditioned on (escape_delay == 2) simply modifies
local data and then breaks out of the loop causing the function to
return escape_data[0].
3. Based on #2 there is not actually any need to ever explicitly set
escape_delay to 2 because we it is much simpler to directly return
escape_data[0] instead.
4. escape_data[0] is, for all but one exit path, known to be '\e'.
Simplify the code based on these observations.
There is a subtle (and harmless) change of behaviour resulting from this
simplification: instead of letting the escape timeout after ~1998
milliseconds we now timeout after ~2000 milliseconds
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191025073328.643-3-daniel.thompson@linaro.org
kdb_read_get_key() has extremely complex break/continue control flow
managed by state variables and is very hard to review or modify. In
particular the way the escape sequence handling interacts with the
general control flow is hard to follow. Separate out the escape key
handling, without changing the control flow. This makes the main body of
the code easier to review.
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Link: https://lore.kernel.org/r/20191025073328.643-2-daniel.thompson@linaro.org
Andi reported that he was hitting the linear search in
perf_init_event() a lot. Now that all !TYPE_SOFTWARE events should hit
the IDR, make sure the TYPE_SOFTWARE events are at the head of the
list such that we'll quickly find the right PMU (provided a valid
event was given).
Signed-off-by: Liang, Kan <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andi reported that he was hitting the linear search in
perf_init_event() a lot. Make more agressive use of the IDR lookup to
avoid hitting the linear search.
With exception of PERF_TYPE_SOFTWARE (which relies on a hideous hack),
we can put everything in the IDR. On top of that, we can alias
TYPE_HARDWARE and TYPE_HW_CACHE to TYPE_RAW on the lookup side.
This greatly reduces the chances of hitting the linear search.
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan <kan.liang@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Andi reported that when creating a lot of events, a lot of time is
spent in IPIs and asked if it would be possible to elide some of that.
Now when, as for example the perf-tool always does, events are created
disabled, then these events will not need to be scheduled when added
to the context (they're still disable) and therefore the IPI is not
required -- except for the very first event, that will need to set
ctx->is_active.
( It might be possible to set ctx->is_active remotely for cpu_ctx, but
we really need the IPI for task_ctx, so lets not make that
distinction. )
Also use __perf_effective_state() since group events depend on the
state of the leader, if the leader is OFF, the whole group is OFF.
So when sibling events are created enabled (XXX check tool) then we
only need a single IPI to create and enable the whole group (+ that
initial IPI to initialize the context).
Suggested-by: Andi Kleen <andi@firstfloor.org>
Reported-by: Andi Kleen <andi@firstfloor.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: acme@kernel.org
Cc: kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
1a59413124 ("perf: Add wakeup watermark control to the AUX area")
added attr.__reserved_2 padding, but forgot to add an ABI check to reject
attributes with this field set. Fix that.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: adrian.hunter@intel.com
Cc: mathieu.poirier@linaro.org
Link: https://lkml.kernel.org/r/20191025121636.75182-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull timer fixes from Thomas Gleixner:
"A small set of fixes for time(keeping):
- Add a missing include to prevent compiler warnings.
- Make the VDSO implementation of clock_getres() POSIX compliant
again. A recent change dropped the NULL pointer guard which is
required as NULL is a valid pointer value for this function.
- Fix two function documentation typos"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
posix-cpu-timers: Fix two trivial comments
timers/sched_clock: Include local timekeeping.h for missing declarations
lib/vdso: Make clock_getres() POSIX compliant again
Pull perf fixes from Thomas Gleixner:
"A set of perf fixes:
kernel:
- Unbreak the tracking of auxiliary buffer allocations which got
imbalanced causing recource limit failures.
- Fix the fallout of splitting of ToPA entries which missed to shift
the base entry PA correctly.
- Use the correct context to lookup the AUX event when unmapping the
associated AUX buffer so the event can be stopped and the buffer
reference dropped.
tools:
- Fix buildiid-cache mode setting in copyfile_mode_ns() when copying
/proc/kcore
- Fix freeing id arrays in the event list so the correct event is
closed.
- Sync sched.h anc kvm.h headers with the kernel sources.
- Link jvmti against tools/lib/ctype.o to have weak strlcpy().
- Fix multiple memory and file descriptor leaks, found by coverity in
perf annotate.
- Fix leaks in error handling paths in 'perf c2c', 'perf kmem', found
by a static analysis tool"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/aux: Fix AUX output stopping
perf/aux: Fix tracking of auxiliary trace buffer allocation
perf/x86/intel/pt: Fix base for single entry topa
perf kmem: Fix memory leak in compact_gfp_flags()
tools headers UAPI: Sync sched.h with the kernel
tools headers kvm: Sync kvm.h headers with the kernel sources
tools headers kvm: Sync kvm headers with the kernel sources
tools headers kvm: Sync kvm headers with the kernel sources
perf c2c: Fix memory leak in build_cl_output()
perf tools: Fix mode setting in copyfile_mode_ns()
perf annotate: Fix multiple memory and file descriptor leaks
perf tools: Fix resource leak of closedir() on the error paths
perf evlist: Fix fix for freed id arrays
perf jvmti: Link against tools/lib/ctype.h to have weak strlcpy()
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-10-27
The following pull-request contains BPF updates for your *net-next* tree.
We've added 52 non-merge commits during the last 11 day(s) which contain
a total of 65 files changed, 2604 insertions(+), 1100 deletions(-).
The main changes are:
1) Revolutionize BPF tracing by using in-kernel BTF to type check BPF
assembly code. The work here teaches BPF verifier to recognize
kfree_skb()'s first argument as 'struct sk_buff *' in tracepoints
such that verifier allows direct use of bpf_skb_event_output() helper
used in tc BPF et al (w/o probing memory access) that dumps skb data
into perf ring buffer. Also add direct loads to probe memory in order
to speed up/replace bpf_probe_read() calls, from Alexei Starovoitov.
2) Big batch of changes to improve libbpf and BPF kselftests. Besides
others: generalization of libbpf's CO-RE relocation support to now
also include field existence relocations, revamp the BPF kselftest
Makefile to add test runner concept allowing to exercise various
ways to build BPF programs, and teach bpf_object__open() and friends
to automatically derive BPF program type/expected attach type from
section names to ease their use, from Andrii Nakryiko.
3) Fix deadlock in stackmap's build-id lookup on rq_lock(), from Song Liu.
4) Allow to read BTF as raw data from bpftool. Most notable use case
is to dump /sys/kernel/btf/vmlinux through this, from Jiri Olsa.
5) Use bpf_redirect_map() helper in libbpf's AF_XDP helper prog which
manages to improve "rx_drop" performance by ~4%., from Björn Töpel.
6) Fix to restore the flow dissector after reattach BPF test and also
fix error handling in bpf_helper_defs.h generation, from Jakub Sitnicki.
7) Improve verifier's BTF ctx access for use outside of raw_tp, from
Martin KaFai Lau.
8) Improve documentation for AF_XDP with new sections and to reflect
latest features, from Magnus Karlsson.
9) Add back 'version' section parsing to libbpf for old kernels, from
John Fastabend.
10) Fix strncat bounds error in libbpf's libbpf_prog_type_by_name(),
from KP Singh.
11) Turn on -mattr=+alu32 in LLVM by default for BPF kselftests in order
to improve insn coverage for built BPF progs, from Yonghong Song.
12) Misc minor cleanups and fixes, from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Daniel Borkmann says:
====================
pull-request: bpf 2019-10-27
The following pull-request contains BPF updates for your *net* tree.
We've added 7 non-merge commits during the last 11 day(s) which contain
a total of 7 files changed, 66 insertions(+), 16 deletions(-).
The main changes are:
1) Fix two use-after-free bugs in relation to RCU in jited symbol exposure to
kallsyms, from Daniel Borkmann.
2) Fix NULL pointer dereference in AF_XDP rx-only sockets, from Magnus Karlsson.
3) Fix hang in netdev unregister for hash based devmap as well as another overflow
bug on 32 bit archs in memlock cost calculation, from Toke Høiland-Jørgensen.
4) Fix wrong memory access in LWT BPF programs on reroute due to invalid dst.
Also fix BPF selftests to use more compatible nc options, from Jiri Benc.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Warning is found by the code analysis tool:
"the condition 'if(ac && rc < 0)' is redundant: ac"
The @ac variable has been checked before. It can't be a null pointer
here, so remove the redundant condition check.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
cgroup_enable_task_cg_lists() is used to lazyily initialize task
cgroup associations on the first use to reduce fork / exit overheads
on systems which don't use cgroup. Unfortunately, locking around it
has never been actually correct and its value is dubious given how the
vast majority of systems use cgroup right away from boot.
This patch removes the optimization. For now, replace the cg_list
based branches with WARN_ON_ONCE()'s to be on the safe side. We can
simplify the logic further in the future.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
This patch makes a few changes to btf_ctx_access() to prepare
it for non raw_tp use case where the attach_btf_id is not
necessary a BTF_KIND_TYPEDEF.
It moves the "btf_trace_" prefix check and typedef-follow logic to a new
function "check_attach_btf_id()" which is called only once during
bpf_check(). btf_ctx_access() only operates on a BTF_KIND_FUNC_PROTO
type now. That should also be more efficient since it is done only
one instead of every-time check_ctx_access() is called.
"check_attach_btf_id()" needs to find the func_proto type from
the attach_btf_id. It needs to store the result into the
newly added prog->aux->attach_func_proto. func_proto
btf type has no name, so a proper name should be stored into
"attach_func_name" also.
v2:
- Move the "btf_trace_" check to an earlier verifier phase (Alexei)
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20191025001811.1718491-1-kafai@fb.com
- Using device PM QoS of CPU devices for managing frequency limits
in cpufreq does not work, so introduce frequency QoS (based on the
original low-level PM QoS) for this purpose, switch cpufreq and
related code over to using it and fix a race involving deferred
updates of frequency limits on top of that (Rafael Wysocki, Sudeep
Holla).
- Avoid calling regulator_enable()/disable() from the OPP framework
to avoid side-effects on boot-enabled regulators that may change their
initial voltage due to performing initial voltage balancing without
all restrictions from the consumers (Marek Szyprowski).
- Avoid a kref management issue in the OPP library code and drop an
incorrectly added lockdep_assert_held() from it (Viresh Kumar).
- Make the recently added haltpoll cpuidle driver take the 'idle='
override into account as appropriate (Zhenzhong Duan).
-----BEGIN PGP SIGNATURE-----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=yitK
-----END PGP SIGNATURE-----
Merge tag 'pm-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These fix problems related to frequency limits management in cpufreq
that were introduced during the 5.3 cycle (when PM QoS had started to
be used for that), fix a few issues in the OPP (operating performance
points) library code and fix up the recently added haltpoll cpuidle
driver.
The cpufreq changes are somewhat bigger that I would like them to be
at this stage of the cycle, but the problems fixed by them include
crashes on boot and shutdown in some cases (among other things) and in
my view it is better to address the root of the issue right away.
Specifics:
- Using device PM QoS of CPU devices for managing frequency limits in
cpufreq does not work, so introduce frequency QoS (based on the
original low-level PM QoS) for this purpose, switch cpufreq and
related code over to using it and fix a race involving deferred
updates of frequency limits on top of that (Rafael Wysocki, Sudeep
Holla).
- Avoid calling regulator_enable()/disable() from the OPP framework
to avoid side-effects on boot-enabled regulators that may change
their initial voltage due to performing initial voltage balancing
without all restrictions from the consumers (Marek Szyprowski).
- Avoid a kref management issue in the OPP library code and drop an
incorrectly added lockdep_assert_held() from it (Viresh Kumar).
- Make the recently added haltpoll cpuidle driver take the 'idle='
override into account as appropriate (Zhenzhong Duan)"
* tag 'pm-5.4-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
opp: Reinitialize the list_kref before adding the static OPPs again
cpufreq: Cancel policy update work scheduled before freeing
cpuidle: haltpoll: Take 'idle=' override into account
opp: core: Revert "add regulators enable and disable"
PM: QoS: Drop frequency QoS types from device PM QoS
cpufreq: Use per-policy frequency QoS
PM: QoS: Introduce frequency QoS
opp: of: drop incorrect lockdep_assert_held()
Because pids->limit can be changed concurrently (but we don't want to
take a lock because it would be needlessly expensive), use atomic64_ts
instead.
Fixes: commit 49b786ea14 ("cgroup: implement the PIDs subsystem")
Cc: stable@vger.kernel.org # v4.3+
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Recent versions of gcc (reported on gcc-7.4) issue array subscript
warnings for builds where SMP is not enabled.
kernel/debug/debug_core.c: In function 'kdb_dump_stack_on_cpu':
kernel/debug/debug_core.c:452:17: warning: array subscript is outside array
+bounds [-Warray-bounds]
if (!(kgdb_info[cpu].exception_state & DCPU_IS_SLAVE)) {
~~~~~~~~~^~~~~
kernel/debug/debug_core.c:469:33: warning: array subscript is outside array
+bounds [-Warray-bounds]
kgdb_info[cpu].exception_state |= DCPU_WANT_BT;
kernel/debug/debug_core.c:470:18: warning: array subscript is outside array
+bounds [-Warray-bounds]
while (kgdb_info[cpu].exception_state & DCPU_WANT_BT)
There is no bug here but there is scope to improve the code
generation for non-SMP systems (whilst also silencing the warning).
Reported-by: kbuild test robot <lkp@intel.com>
Fixes: 2277b49258 ("kdb: Fix stack crawling on 'running' CPUs that aren't the master")
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Link: https://lore.kernel.org/r/20191021101057.23861-1-daniel.thompson@linaro.org
Reviewed-by: Douglas Anderson <dianders@chromium.org>
- A race in perf trace initialization (missing mutexes)
- Minor fix to represent gfp_t in synthetic events as properly signed
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXa5C9hQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qrFqAP9FskyS8xr1iqquWGarC38jYaLg8C2c
7ou+tdIm+Rez5QEA+3E456Esusmx3dACk2QLeb788Pf1wQOjKXyZ9H+2eAE=
=ys+Y
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.4-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two minor fixes:
- A race in perf trace initialization (missing mutexes)
- Minor fix to represent gfp_t in synthetic events as properly
signed"
* tag 'trace-v5.4-rc3-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix race in perf_trace_buf initialization
tracing: Fix "gfp_t" format for synthetic events
Remove the nr_exclusive argument from __wake_up_sync_key() and derived
functions as everything seems to set it to 1. Note also that if it wasn't
set to 1, it would clear WF_SYNC anyway.
Signed-off-by: David Howells <dhowells@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Recent changes modified the function arguments of
thread_group_sample_cputime() and task_cputimers_expired(), but forgot to
update the comments. Fix it up.
[ tglx: Changed the argument name of task_cputimers_expired() as the pointer
points to an array of samples. ]
Fixes: b7be4ef136 ("posix-cpu-timers: Switch thread group sampling to array")
Fixes: 001f797143 ("posix-cpu-timers: Make expiry checks array based")
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1571643852-21848-1-git-send-email-wang.yi59@zte.com.cn
Include the timekeeping.h header to get the declaration of the
sched_clock_{suspend,resume} functions. Fixes the following sparse
warnings:
kernel/time/sched_clock.c:275:5: warning: symbol 'sched_clock_suspend' was not declared. Should it be static?
kernel/time/sched_clock.c:286:6: warning: symbol 'sched_clock_resume' was not declared. Should it be static?
Signed-off-by: Ben Dooks (Codethink) <ben.dooks@codethink.co.uk>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191022131226.11465-1-ben.dooks@codethink.co.uk
There is one more problematic case I noticed while recently fixing BPF kallsyms
handling in cd7455f101 ("bpf: Fix use after free in subprog's jited symbol
removal") and that is bpf_get_prog_name().
If BTF has been attached to the prog, then we may be able to fetch the function
signature type id in kallsyms through prog->aux->func_info[prog->aux->func_idx].type_id.
However, while the BTF object itself is torn down via RCU callback, the prog's
aux->func_info is immediately freed via kvfree(prog->aux->func_info) once the
prog's refcount either hit zero or when subprograms were already exposed via
kallsyms and we hit the error path added in 5482e9a93c ("bpf: Fix memleak in
aux->func_info and aux->btf").
This violates RCU as well since kallsyms could be walked in parallel where we
could access aux->func_info. Hence, defer kvfree() to after RCU grace period.
Looking at ba64e7d852 ("bpf: btf: support proper non-jit func info") there
is no reason/dependency where we couldn't defer the kvfree(aux->func_info) into
the RCU callback.
Fixes: 5482e9a93c ("bpf: Fix memleak in aux->func_info and aux->btf")
Fixes: ba64e7d852 ("bpf: btf: support proper non-jit func info")
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Cc: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/875f2906a7c1a0691f2d567b4d8e4ea2739b1e88.1571779205.git.daniel@iogearbox.net
syzkaller managed to trigger the following crash:
[...]
BUG: unable to handle page fault for address: ffffc90001923030
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD aa551067 P4D aa551067 PUD aa552067 PMD a572b067 PTE 80000000a1173163
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 7982 Comm: syz-executor912 Not tainted 5.4.0-rc3+ #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:bpf_jit_binary_hdr include/linux/filter.h:787 [inline]
RIP: 0010:bpf_get_prog_addr_region kernel/bpf/core.c:531 [inline]
RIP: 0010:bpf_tree_comp kernel/bpf/core.c:600 [inline]
RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline]
RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
RIP: 0010:bpf_prog_kallsyms_find kernel/bpf/core.c:674 [inline]
RIP: 0010:is_bpf_text_address+0x184/0x3b0 kernel/bpf/core.c:709
[...]
Call Trace:
kernel_text_address kernel/extable.c:147 [inline]
__kernel_text_address+0x9a/0x110 kernel/extable.c:102
unwind_get_return_address+0x4c/0x90 arch/x86/kernel/unwind_frame.c:19
arch_stack_walk+0x98/0xe0 arch/x86/kernel/stacktrace.c:26
stack_trace_save+0xb6/0x150 kernel/stacktrace.c:123
save_stack mm/kasan/common.c:69 [inline]
set_track mm/kasan/common.c:77 [inline]
__kasan_kmalloc+0x11c/0x1b0 mm/kasan/common.c:510
kasan_slab_alloc+0xf/0x20 mm/kasan/common.c:518
slab_post_alloc_hook mm/slab.h:584 [inline]
slab_alloc mm/slab.c:3319 [inline]
kmem_cache_alloc+0x1f5/0x2e0 mm/slab.c:3483
getname_flags+0xba/0x640 fs/namei.c:138
getname+0x19/0x20 fs/namei.c:209
do_sys_open+0x261/0x560 fs/open.c:1091
__do_sys_open fs/open.c:1115 [inline]
__se_sys_open fs/open.c:1110 [inline]
__x64_sys_open+0x87/0x90 fs/open.c:1110
do_syscall_64+0xf7/0x1c0 arch/x86/entry/common.c:290
entry_SYSCALL_64_after_hwframe+0x49/0xbe
[...]
After further debugging it turns out that we walk kallsyms while in parallel
we tear down a BPF program which contains subprograms that have been JITed
though the program itself has not been fully exposed and is eventually bailing
out with error.
The bpf_prog_kallsyms_del_subprogs() in bpf_prog_load()'s error path removes
the symbols, however, bpf_prog_free() tears down the JIT memory too early via
scheduled work. Instead, it needs to properly respect RCU grace period as the
kallsyms walk for BPF is under RCU.
Fix it by refactoring __bpf_prog_put()'s tear down and reuse it in our error
path where we defer final destruction when we have subprogs in the program.
Fixes: 7d1982b4e3 ("bpf: fix panic in prog load calls cleanup")
Fixes: 1c2a088a66 ("bpf: x64: add JIT support for multi-function programs")
Reported-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: syzbot+710043c5d1d5b5013bc7@syzkaller.appspotmail.com
Link: https://lore.kernel.org/bpf/55f6367324c2d7e9583fa9ccf5385dcbba0d7a6e.1571752452.git.daniel@iogearbox.net
Commit:
8a58ddae23 ("perf/core: Fix exclusive events' grouping")
allows CAP_EXCLUSIVE events to be grouped with other events. Since all
of those also happen to be AUX events (which is not the case the other
way around, because arch/s390), this changes the rules for stopping the
output: the AUX event may not be on its PMU's context any more, if it's
grouped with a HW event, in which case it will be on that HW event's
context instead. If that's the case, munmap() of the AUX buffer can't
find and stop the AUX event, potentially leaving the last reference with
the atomic context, which will then end up freeing the AUX buffer. This
will then trip warnings:
Fix this by using the context's PMU context when looking for events
to stop, instead of the event's PMU context.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20191022073940.61814-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It seems I forgot to add handling of devmap_hash type maps to the device
unregister hook for devmaps. This omission causes devices to not be
properly released, which causes hangs.
Fix this by adding the missing handler.
Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191019111931.2981954-1-toke@redhat.com
Reset all signal handlers of the child not set to SIG_IGN to SIG_DFL.
Mutually exclusive with CLONE_SIGHAND to not disturb other thread's
signal handler.
In the spirit of closer cooperation between glibc developers and kernel
developers (cf. [2]) this patchset came out of a discussion on the glibc
mailing list for improving posix_spawn() (cf. [1], [3], [4]). Kernel
support for this feature has been explicitly requested by glibc and I
see no reason not to help them with this.
The child helper process on Linux posix_spawn must ensure that no signal
handlers are enabled, so the signal disposition must be either SIG_DFL
or SIG_IGN. However, it requires a sigprocmask to obtain the current
signal mask and at least _NSIG sigaction calls to reset the signal
handlers for each posix_spawn call or complex state tracking that might
lead to data corruption in glibc. Adding this flags lets glibc avoid
these problems.
[1]: https://www.sourceware.org/ml/libc-alpha/2019-10/msg00149.html
[3]: https://www.sourceware.org/ml/libc-alpha/2019-10/msg00158.html
[4]: https://www.sourceware.org/ml/libc-alpha/2019-10/msg00160.html
[2]: https://lwn.net/Articles/799331/
'[...] by asking for better cooperation with the C-library projects
in general. They should be copied on patches containing ABI
changes, for example. I noted that there are often times where
C-library developers wish the kernel community had done things
differently; how could those be avoided in the future? Members of
the audience suggested that more glibc developers should perhaps
join the linux-api list. The other suggestion was to "copy Florian
on everything".'
Cc: Florian Weimer <fweimer@redhat.com>
Cc: libc-alpha@sourceware.org
Cc: linux-api@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20191014104538.3096-1-christian.brauner@ubuntu.com
The following commit from the v5.4 merge window:
d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
... breaks auxiliary trace buffer tracking.
If I run command 'perf record -e rbd000' to record samples and saving
them in the **auxiliary** trace buffer then the value of 'locked_vm' becomes
negative after all trace buffers have been allocated and released:
During allocation the values increase:
[52.250027] perf_mmap user->locked_vm:0x87 pinned_vm:0x0 ret:0
[52.250115] perf_mmap user->locked_vm:0x107 pinned_vm:0x0 ret:0
[52.250251] perf_mmap user->locked_vm:0x188 pinned_vm:0x0 ret:0
[52.250326] perf_mmap user->locked_vm:0x208 pinned_vm:0x0 ret:0
[52.250441] perf_mmap user->locked_vm:0x289 pinned_vm:0x0 ret:0
[52.250498] perf_mmap user->locked_vm:0x309 pinned_vm:0x0 ret:0
[52.250613] perf_mmap user->locked_vm:0x38a pinned_vm:0x0 ret:0
[52.250715] perf_mmap user->locked_vm:0x408 pinned_vm:0x2 ret:0
[52.250834] perf_mmap user->locked_vm:0x408 pinned_vm:0x83 ret:0
[52.250915] perf_mmap user->locked_vm:0x408 pinned_vm:0x103 ret:0
[52.251061] perf_mmap user->locked_vm:0x408 pinned_vm:0x184 ret:0
[52.251146] perf_mmap user->locked_vm:0x408 pinned_vm:0x204 ret:0
[52.251299] perf_mmap user->locked_vm:0x408 pinned_vm:0x285 ret:0
[52.251383] perf_mmap user->locked_vm:0x408 pinned_vm:0x305 ret:0
[52.251544] perf_mmap user->locked_vm:0x408 pinned_vm:0x386 ret:0
[52.251634] perf_mmap user->locked_vm:0x408 pinned_vm:0x406 ret:0
[52.253018] perf_mmap user->locked_vm:0x408 pinned_vm:0x487 ret:0
[52.253197] perf_mmap user->locked_vm:0x408 pinned_vm:0x508 ret:0
[52.253374] perf_mmap user->locked_vm:0x408 pinned_vm:0x589 ret:0
[52.253550] perf_mmap user->locked_vm:0x408 pinned_vm:0x60a ret:0
[52.253726] perf_mmap user->locked_vm:0x408 pinned_vm:0x68b ret:0
[52.253903] perf_mmap user->locked_vm:0x408 pinned_vm:0x70c ret:0
[52.254084] perf_mmap user->locked_vm:0x408 pinned_vm:0x78d ret:0
[52.254263] perf_mmap user->locked_vm:0x408 pinned_vm:0x80e ret:0
The value of user->locked_vm increases to a limit then the memory
is tracked by pinned_vm.
During deallocation the size is subtracted from pinned_vm until
it hits a limit. Then a larger value is subtracted from locked_vm
leading to a large number (because of type unsigned):
[64.267797] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x78d
[64.267826] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x70c
[64.267848] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x68b
[64.267869] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x60a
[64.267891] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x589
[64.267911] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x508
[64.267933] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x487
[64.267952] perf_mmap_close mmap_user->locked_vm:0x408 pinned_vm:0x406
[64.268883] perf_mmap_close mmap_user->locked_vm:0x307 pinned_vm:0x406
[64.269117] perf_mmap_close mmap_user->locked_vm:0x206 pinned_vm:0x406
[64.269433] perf_mmap_close mmap_user->locked_vm:0x105 pinned_vm:0x406
[64.269536] perf_mmap_close mmap_user->locked_vm:0x4 pinned_vm:0x404
[64.269797] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff84 pinned_vm:0x303
[64.270105] perf_mmap_close mmap_user->locked_vm:0xffffffffffffff04 pinned_vm:0x202
[64.270374] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe84 pinned_vm:0x101
[64.270628] perf_mmap_close mmap_user->locked_vm:0xfffffffffffffe04 pinned_vm:0x0
This value sticks for the user until system is rebooted, causing
follow-on system calls using locked_vm resource limit to fail.
Note: There is no issue using the normal trace buffer.
In fact the issue is in perf_mmap_close(). During allocation auxiliary
trace buffer memory is either traced as 'extra' and added to 'pinned_vm'
or trace as 'user_extra' and added to 'locked_vm'. This applies for
normal trace buffers and auxiliary trace buffer.
However in function perf_mmap_close() all auxiliary trace buffer is
subtraced from 'locked_vm' and never from 'pinned_vm'. This breaks the
ballance.
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: acme@kernel.org
Cc: gor@linux.ibm.com
Cc: hechaol@fb.com
Cc: heiko.carstens@de.ibm.com
Cc: linux-perf-users@vger.kernel.org
Cc: songliubraving@fb.com
Fixes: d44248a413 ("perf/core: Rework memory accounting in perf_mmap()")
Link: https://lkml.kernel.org/r/20191021083354.67868-1-tmricht@linux.ibm.com
[ Minor readability edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The slow wake up path computes per sched_group statisics to select the
idlest group, which is quite similar to what load_balance() is doing
for selecting busiest group. Rework find_idlest_group() to classify the
sched_group and select the idlest one following the same steps as
load_balance().
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/1571405198-27570-12-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Runnable load was originally introduced to take into account the case where
blocked load biases the wake up path which may end to select an overloaded
CPU with a large number of runnable tasks instead of an underutilized
CPU with a huge blocked load.
Tha wake up path now starts looking for idle CPUs before comparing
runnable load and it's worth aligning the wake up path with the
load_balance() logic.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/1571405198-27570-10-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Utilization is used to detect a misfit task but the load is then used to
select the task on the CPU which can lead to select a small task with
high weight instead of the task that triggered the misfit migration.
Check that task can't fit the CPU's capacity when selecting the misfit
task instead of using the load.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Valentin Schneider <valentin.schneider@arm.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Link: https://lkml.kernel.org/r/1571405198-27570-9-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
'runnable load' was originally introduced to take into account the case
where blocked load biases the load balance decision which was selecting
underutilized groups with huge blocked load whereas other groups were
overloaded.
The load is now only used when groups are overloaded. In this case,
it's worth being conservative and taking into account the sleeping
tasks that might wake up on the CPU.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/1571405198-27570-7-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CFS load_balance() only takes care of CFS tasks whereas CPUs can be used by
other scheduling classes. Typically, a CFS task preempted by an RT or deadline
task will not get a chance to be pulled by another CPU because
load_balance() doesn't take into account tasks from other classes.
Add sum of nr_running in the statistics and use it to detect such
situations.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/1571405198-27570-6-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The load_balance() algorithm contains some heuristics which have become
meaningless since the rework of the scheduler's metrics like the
introduction of PELT.
Furthermore, load is an ill-suited metric for solving certain task
placement imbalance scenarios.
For instance, in the presence of idle CPUs, we should simply try to get at
least one task per CPU, whereas the current load-based algorithm can actually
leave idle CPUs alone simply because the load is somewhat balanced.
The current algorithm ends up creating virtual and meaningless values like
the avg_load_per_task or tweaks the state of a group to make it overloaded
whereas it's not, in order to try to migrate tasks.
load_balance() should better qualify the imbalance of the group and clearly
define what has to be moved to fix this imbalance.
The type of sched_group has been extended to better reflect the type of
imbalance. We now have:
group_has_spare
group_fully_busy
group_misfit_task
group_asym_packing
group_imbalanced
group_overloaded
Based on the type of sched_group, load_balance now sets what it wants to
move in order to fix the imbalance. It can be some load as before but also
some utilization, a number of task or a type of task:
migrate_task
migrate_util
migrate_load
migrate_misfit
This new load_balance() algorithm fixes several pending wrong tasks
placement:
- the 1 task per CPU case with asymmetric system
- the case of cfs task preempted by other class
- the case of tasks not evenly spread on groups with spare capacity
Also the load balance decisions have been consolidated in the 3 functions
below after removing the few bypasses and hacks of the current code:
- update_sd_pick_busiest() select the busiest sched_group.
- find_busiest_group() checks if there is an imbalance between local and
busiest group.
- calculate_imbalance() decides what have to be moved.
Finally, the now unused field total_running of struct sd_lb_stats has been
removed.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: riel@surriel.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/1571405198-27570-5-git-send-email-vincent.guittot@linaro.org
[ Small readability and spelling updates. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rename sum_nr_running to sum_h_nr_running because it effectively tracks
cfs->h_nr_running so we can use sum_nr_running to track rq->nr_running
when needed.
There are no functional changes.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Acked-by: Rik van Riel <riel@surriel.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: srikar@linux.vnet.ibm.com
Link: https://lkml.kernel.org/r/1571405198-27570-3-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Clean up asym packing to follow the default load balance behavior:
- classify the group by creating a group_asym_packing field.
- calculate the imbalance in calculate_imbalance() instead of bypassing it.
We don't need to test twice same conditions anymore to detect asym packing
and we consolidate the calculation of imbalance in calculate_imbalance().
There is no functional changes.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Acked-by: Rik van Riel <riel@surriel.com>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Morten.Rasmussen@arm.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: hdanton@sina.com
Cc: parth@linux.ibm.com
Cc: pauld@redhat.com
Cc: quentin.perret@arm.com
Cc: srikar@linux.vnet.ibm.com
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/1571405198-27570-2-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce frequency QoS, based on the "raw" low-level PM QoS, to
represent min and max frequency requests and aggregate constraints.
The min and max frequency requests are to be represented by
struct freq_qos_request objects and the aggregate constraints are to
be represented by struct freq_constraints objects. The latter are
expected to be initialized with the help of freq_constraints_init().
The freq_qos_read_value() helper is defined to retrieve the aggregate
constraints values from a given struct freq_constraints object and
there are the freq_qos_add_request(), freq_qos_update_request() and
freq_qos_remove_request() helpers to manipulate the min and max
frequency requests. It is assumed that the the helpers will not
run concurrently with each other for the same struct freq_qos_request
object, so if that may be the case, their uses must ensure proper
synchronization between them (e.g. through locking).
In addition, freq_qos_add_notifier() and freq_qos_remove_notifier()
are provided to add and remove notifiers that will trigger on aggregate
constraint changes to and from a given struct freq_constraints object,
respectively.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
When looking for a bit by number we make use of the cached result from the
preceding lookup to speed up operation. Firstly we check if the requested
pfn is within the cached zone and if not lookup the new zone. We then
check if the offset for that pfn falls within the existing cached node.
This happens regardless of whether the node is within the zone we are
now scanning. With certain memory layouts it is possible for this to
false trigger creating a temporary alias for the pfn to a different bit.
This leads the hibernation code to free memory which it was never allocated
with the expected fallout.
Ensure the zone we are scanning matches the cached zone before considering
the cached node.
Deep thanks go to Andrea for many, many, many hours of hacking and testing
that went into cornering this bug.
Reported-by: Andrea Righi <andrea.righi@canonical.com>
Tested-by: Andrea Righi <andrea.righi@canonical.com>
Signed-off-by: Andy Whitcroft <apw@canonical.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
- fix a bashism of setlocalversion
- do not use the too new --sort option of tar
-----BEGIN PGP SIGNATURE-----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=KNWF
-----END PGP SIGNATURE-----
Merge tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull more Kbuild fixes from Masahiro Yamada:
- fix a bashism of setlocalversion
- do not use the too new --sort option of tar
* tag 'kbuild-fixes-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kheaders: substituting --sort in archive creation
scripts: setlocalversion: fix a bashism
kbuild: update comment about KBUILD_ALLDIRS
Pull hrtimer fixlet from Thomas Gleixner:
"A single commit annotating the lockcless access to timer->base with
READ_ONCE() and adding the WRITE_ONCE() counterparts for completeness"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
hrtimer: Annotate lockless access to timer->base
Pull stop-machine fix from Thomas Gleixner:
"A single fix, amending stop machine with WRITE/READ_ONCE() to address
the fallout of KCSAN"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stop_machine: Avoid potential race behaviour
Attaching uprobe to text section in THP splits the PMD mapped page table
into PTE mapped entries. On uprobe detach, we would like to regroup PMD
mapped page table entry to regain performance benefit of THP.
However, the regroup is broken For perf_event based trace_uprobe. This
is because perf_event based trace_uprobe calls uprobe_unregister twice
on close: first in TRACE_REG_PERF_CLOSE, then in
TRACE_REG_PERF_UNREGISTER. The second call will split the PMD mapped
page table entry, which is not the desired behavior.
Fix this by only use FOLL_SPLIT_PMD for uprobe register case.
Add a WARN() to confirm uprobe unregister never work on huge pages, and
abort the operation when this WARN() triggers.
Link: http://lkml.kernel.org/r/20191017164223.2762148-6-songliubraving@fb.com
Fixes: 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT")
Signed-off-by: Song Liu <songliubraving@fb.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: William Kucharski <william.kucharski@oracle.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Tetsuo pointed out that without an explicit cast, the cost calculation for
devmap_hash type maps could overflow on 32-bit builds. This adds the
missing cast.
Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-by: Tetsuo Handa <penguin-kernel@i-love.sakura.ne.jp>
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191017105702.2807093-1-toke@redhat.com
If CONFIG_NET is n, building fails:
kernel/trace/bpf_trace.o: In function `raw_tp_prog_func_proto':
bpf_trace.c:(.text+0x1a34): undefined reference to `bpf_skb_output_proto'
Wrap it into a #ifdef to fix this.
Fixes: a7658e1a41 ("bpf: Check types of arguments passed into helpers")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191018090344.26936-1-yuehaibing@huawei.com
Only raw_tracepoint program type can have bpf_attr.attach_btf_id >= 0.
Make sure to reject other program types that accidentally set it to non-zero.
Fixes: ccfe29eb29 ("bpf: Add attach_btf_id attribute to program load")
Reported-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20191018060933.2950231-1-ast@kernel.org
In the format of synthetic events, the "gfp_t" is shown as "signed:1",
but in fact the "gfp_t" is "unsigned", should be shown as "signed:0".
The issue can be reproduced by the following commands:
echo 'memlatency u64 lat; unsigned int order; gfp_t gfp_flags; int migratetype' > /sys/kernel/debug/tracing/synthetic_events
cat /sys/kernel/debug/tracing/events/synthetic/memlatency/format
name: memlatency
ID: 2233
format:
field:unsigned short common_type; offset:0; size:2; signed:0;
field:unsigned char common_flags; offset:2; size:1; signed:0;
field:unsigned char common_preempt_count; offset:3; size:1; signed:0;
field:int common_pid; offset:4; size:4; signed:1;
field:u64 lat; offset:8; size:8; signed:0;
field:unsigned int order; offset:16; size:4; signed:0;
field:gfp_t gfp_flags; offset:24; size:4; signed:1;
field:int migratetype; offset:32; size:4; signed:1;
print fmt: "lat=%llu, order=%u, gfp_flags=%x, migratetype=%d", REC->lat, REC->order, REC->gfp_flags, REC->migratetype
Link: http://lkml.kernel.org/r/20191018012034.6404-1-zhengjun.xing@linux.intel.com
Reviewed-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Fix possible NULL pointer dereference in the ACPI processor
scaling initialization code introduced by a recent cpufreq
update (Rafael Wysocki).
- Fix possible deadlock due to suspending cpufreq too late during
system shutdown (Rafael Wysocki).
- Make the PCI device system resume code path be more consistent
with its PM-runtime counterpart to fix an issue with missing
delay on transitions from D3cold to D0 during system resume from
suspend-to-idle on some systems (Rafael Wysocki).
- Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it
use suspend-to-idle by default (Mario Limonciello).
- Fix build warning in the core system suspend support code (Ben
Dooks).
-----BEGIN PGP SIGNATURE-----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=67IL
-----END PGP SIGNATURE-----
Merge tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These include a fix for a recent regression in the ACPI CPU
performance scaling code, a PCI device power management fix,
a system shutdown fix related to cpufreq, a removal of an ACPI
suspend-to-idle blacklist entry and a build warning fix.
Specifics:
- Fix possible NULL pointer dereference in the ACPI processor scaling
initialization code introduced by a recent cpufreq update (Rafael
Wysocki).
- Fix possible deadlock due to suspending cpufreq too late during
system shutdown (Rafael Wysocki).
- Make the PCI device system resume code path be more consistent with
its PM-runtime counterpart to fix an issue with missing delay on
transitions from D3cold to D0 during system resume from
suspend-to-idle on some systems (Rafael Wysocki).
- Drop Dell XPS13 9360 from the LPS0 Idle _DSM blacklist to make it
use suspend-to-idle by default (Mario Limonciello).
- Fix build warning in the core system suspend support code (Ben
Dooks)"
* tag 'pm-5.4-rc4' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
ACPI: processor: Avoid NULL pointer dereferences at init time
PCI: PM: Fix pci_power_up()
PM: sleep: include <linux/pm_runtime.h> for pm_wq
cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown
ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
As said in commit f2c2cbcc35 ("powerpc: Use pr_warn instead of
pr_warning"), removing pr_warning so all logging messages use a
consistent <prefix>_warn style. Let's do it.
Link: http://lkml.kernel.org/r/20191018031850.48498-26-wangkefeng.wang@huawei.com
To: linux-kernel@vger.kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
As said in commit f2c2cbcc35 ("powerpc: Use pr_warn instead of
pr_warning"), removing pr_warning so all logging messages use a
consistent <prefix>_warn style. Let's do it.
Link: http://lkml.kernel.org/r/20191018031850.48498-25-wangkefeng.wang@huawei.com
To: linux-kernel@vger.kernel.org
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
* pm-cpufreq:
ACPI: processor: Avoid NULL pointer dereferences at init time
cpufreq: Avoid cpufreq_suspend() deadlock on system shutdown
* pm-sleep:
PM: sleep: include <linux/pm_runtime.h> for pm_wq
ACPI: PM: Drop Dell XPS13 9360 from LPS0 Idle _DSM blacklist
Currently perf_mmap_alloc_page() is used to allocate memory in
rb_alloc(), but using free_page() to free memory in the failure path.
It's better to use perf_mmap_free_page() instead.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <jolsa@redhat.co>
Cc: <acme@kernel.org>
Cc: <mingo@redhat.com>
Cc: <mark.rutland@arm.com>
Cc: <namhyung@kernel.org>
Cc: <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/575c7e8c-90c7-4e3a-b41d-f894d8cdbd7f@huawei.com
In perf_mmap_free_page(), the unsigned long type is converted to the
pointer type, but where the call is made, the pointer type is converted
to the unsigned long type. There is no need to do these operations.
Modify the parameter type of perf_mmap_free_page() to pointer type.
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <jolsa@redhat.co>
Cc: <acme@kernel.org>
Cc: <mingo@redhat.com>
Cc: <mark.rutland@arm.com>
Cc: <namhyung@kernel.org>
Cc: <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/e6ae3f0c-d04c-50f9-544a-aee3b30330cd@huawei.com
In current mainline, the degree of access to perf_event_open(2) system
call depends on the perf_event_paranoid sysctl. This has a number of
limitations:
1. The sysctl is only a single value. Many types of accesses are controlled
based on the single value thus making the control very limited and
coarse grained.
2. The sysctl is global, so if the sysctl is changed, then that means
all processes get access to perf_event_open(2) opening the door to
security issues.
This patch adds LSM and SELinux access checking which will be used in
Android to access perf_event_open(2) for the purposes of attaching BPF
programs to tracepoints, perf profiling and other operations from
userspace. These operations are intended for production systems.
5 new LSM hooks are added:
1. perf_event_open: This controls access during the perf_event_open(2)
syscall itself. The hook is called from all the places that the
perf_event_paranoid sysctl is checked to keep it consistent with the
systctl. The hook gets passed a 'type' argument which controls CPU,
kernel and tracepoint accesses (in this context, CPU, kernel and
tracepoint have the same semantics as the perf_event_paranoid sysctl).
Additionally, I added an 'open' type which is similar to
perf_event_paranoid sysctl == 3 patch carried in Android and several other
distros but was rejected in mainline [1] in 2016.
2. perf_event_alloc: This allocates a new security object for the event
which stores the current SID within the event. It will be useful when
the perf event's FD is passed through IPC to another process which may
try to read the FD. Appropriate security checks will limit access.
3. perf_event_free: Called when the event is closed.
4. perf_event_read: Called from the read(2) and mmap(2) syscalls for the event.
5. perf_event_write: Called from the ioctl(2) syscalls for the event.
[1] https://lwn.net/Articles/696240/
Since Peter had suggest LSM hooks in 2016 [1], I am adding his
Suggested-by tag below.
To use this patch, we set the perf_event_paranoid sysctl to -1 and then
apply selinux checking as appropriate (default deny everything, and then
add policy rules to give access to domains that need it). In the future
we can remove the perf_event_paranoid sysctl altogether.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Co-developed-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: James Morris <jmorris@namei.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: rostedt@goodmis.org
Cc: Yonghong Song <yhs@fb.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: jeffv@google.com
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: primiano@google.com
Cc: Song Liu <songliubraving@fb.com>
Cc: rsavitski@google.com
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Matthew Garrett <matthewgarrett@google.com>
Link: https://lkml.kernel.org/r/20191014170308.70668-1-joel@joelfernandes.org
As pointed out in commit
182a85f8a1 ("sched: Disable wakeup balancing")
SD_BALANCE_WAKE is a tad too aggressive, and is usually left unset.
However, it turns out cpuset domain relaxation will unconditionally set it
on domains below the relaxation level. This made sense back when
SD_BALANCE_WAKE was set unconditionally, but it no longer is the case.
We can improve things slightly by noticing that set_domain_attribute() is
always called after sd_init(), so rather than setting flags we can rely on
whatever sd_init() is doing and only clear certain flags when above the
relaxation level.
While at it, slightly clean up the function and flip the relax level
check to be more human readable.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: mingo@kernel.org
Cc: vincent.guittot@linaro.org
Cc: juri.lelli@redhat.com
Cc: seto.hidetoshi@jp.fujitsu.com
Cc: qperret@google.com
Cc: Dietmar.Eggemann@arm.com
Cc: morten.rasmussen@arm.com
Link: https://lkml.kernel.org/r/20191014164408.32596-1-valentin.schneider@arm.com
Introduce new helper that reuses existing skb perf_event output
implementation, but can be called from raw_tracepoint programs
that receive 'struct sk_buff *' as tracepoint argument or
can walk other kernel data structures to skb pointer.
In order to do that teach verifier to resolve true C types
of bpf helpers into in-kernel BTF ids.
The type of kernel pointer passed by raw tracepoint into bpf
program will be tracked by the verifier all the way until
it's passed into helper function.
For example:
kfree_skb() kernel function calls trace_kfree_skb(skb, loc);
bpf programs receives that skb pointer and may eventually
pass it into bpf_skb_output() bpf helper which in-kernel is
implemented via bpf_skb_event_output() kernel function.
Its first argument in the kernel is 'struct sk_buff *'.
The verifier makes sure that types match all the way.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-11-ast@kernel.org
Pointer to BTF object is a pointer to kernel object or NULL.
Such pointers can only be used by BPF_LDX instructions.
The verifier changed their opcode from LDX|MEM|size
to LDX|PROBE_MEM|size to make JITing easier.
The number of entries in extable is the number of BPF_LDX insns
that access kernel memory via "pointer to BTF type".
Only these load instructions can fault.
Since x86 extable is relative it has to be allocated in the same
memory region as JITed code.
Allocate it prior to last pass of JITing and let the last pass populate it.
Pointer to extable in bpf_prog_aux is necessary to make page fault
handling fast.
Page fault handling is done in two steps:
1. bpf_prog_kallsyms_find() finds BPF program that page faulted.
It's done by walking rb tree.
2. then extable for given bpf program is binary searched.
This process is similar to how page faulting is done for kernel modules.
The exception handler skips over faulting x86 instruction and
initializes destination register with zero. This mimics exact
behavior of bpf_probe_read (when probe_kernel_read faults dest is zeroed).
JITs for other architectures can add support in similar way.
Until then they will reject unknown opcode and fallback to interpreter.
Since extable should be aligned and placed near JITed code
make bpf_jit_binary_alloc() return 4 byte aligned image offset,
so that extable aligning formula in bpf_int_jit_compile() doesn't need
to rely on internal implementation of bpf_jit_binary_alloc().
On x86 gcc defaults to 16-byte alignment for regular kernel functions
due to better performance. JITed code may be aligned to 16 in the future,
but it will use 4 in the meantime.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-10-ast@kernel.org
Pointer to BTF object is a pointer to kernel object or NULL.
The memory access in the interpreter has to be done via probe_kernel_read
to avoid page faults.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-9-ast@kernel.org
BTF type id specified at program load time has all
necessary information to attach that program to raw tracepoint.
Use kernel type name to find raw tracepoint.
Add missing CHECK_ATTR() condition.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-8-ast@kernel.org
libbpf analyzes bpf C program, searches in-kernel BTF for given type name
and stores it into expected_attach_type.
The kernel verifier expects this btf_id to point to something like:
typedef void (*btf_trace_kfree_skb)(void *, struct sk_buff *skb, void *loc);
which represents signature of raw_tracepoint "kfree_skb".
Then btf_ctx_access() matches ctx+0 access in bpf program with 'skb'
and 'ctx+8' access with 'loc' arguments of "kfree_skb" tracepoint.
In first case it passes btf_id of 'struct sk_buff *' back to the verifier core
and 'void *' in second case.
Then the verifier tracks PTR_TO_BTF_ID as any other pointer type.
Like PTR_TO_SOCKET points to 'struct bpf_sock',
PTR_TO_TCP_SOCK points to 'struct bpf_tcp_sock', and so on.
PTR_TO_BTF_ID points to in-kernel structs.
If 1234 is btf_id of 'struct sk_buff' in vmlinux's BTF
then PTR_TO_BTF_ID#1234 points to one of in kernel skbs.
When PTR_TO_BTF_ID#1234 is dereferenced (like r2 = *(u64 *)r1 + 32)
the btf_struct_access() checks which field of 'struct sk_buff' is
at offset 32. Checks that size of access matches type definition
of the field and continues to track the dereferenced type.
If that field was a pointer to 'struct net_device' the r2's type
will be PTR_TO_BTF_ID#456. Where 456 is btf_id of 'struct net_device'
in vmlinux's BTF.
Such verifier analysis prevents "cheating" in BPF C program.
The program cannot cast arbitrary pointer to 'struct sk_buff *'
and access it. C compiler would allow type cast, of course,
but the verifier will notice type mismatch based on BPF assembly
and in-kernel BTF.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-7-ast@kernel.org
Add attach_btf_id attribute to prog_load command.
It's similar to existing expected_attach_type attribute which is
used in several cgroup based program types.
Unfortunately expected_attach_type is ignored for
tracing programs and cannot be reused for new purpose.
Hence introduce attach_btf_id to verify bpf programs against
given in-kernel BTF type id at load time.
It is strictly checked to be valid for raw_tp programs only.
In a later patches it will become:
btf_id == 0 semantics of existing raw_tp progs.
btd_id > 0 raw_tp with BTF and additional type safety.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-5-ast@kernel.org
If in-kernel BTF exists parse it and prepare 'struct btf *btf_vmlinux'
for further use by the verifier.
In-kernel BTF is trusted just like kallsyms and other build artifacts
embedded into vmlinux.
Yet run this BTF image through BTF verifier to make sure
that it is valid and it wasn't mangled during the build.
If in-kernel BTF is incorrect it means either gcc or pahole or kernel
are buggy. In such case disallow loading BPF programs.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191016032505.2089704-4-ast@kernel.org
Use the new pid_has_task() helper in pidfd_open(). This simplifies the
code and avoids taking rcu_read_{lock,unlock}() and leads to overall
nicer code.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20191017101832.5985-5-christian.brauner@ubuntu.com
Replace hlist_empty() with the new pid_has_task() helper which is more
idiomatic, easier to grep for, and unifies how callers perform this check.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20191017101832.5985-4-christian.brauner@ubuntu.com
Replace hlist_empty() with the new pid_has_task() helper which is more
idiomatic, easier to grep for, and unifies how callers perform this
check.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20191017101832.5985-3-christian.brauner@ubuntu.com
Currently, when a task is dead we still print the pid it used to use in
the fdinfo files of its pidfds. This doesn't make much sense since the
pid may have already been reused. So verify that the task is still alive
by introducing the pid_has_task() helper which will be used by other
callers in follow-up patches.
If the task is not alive anymore, we will print -1. This allows us to
differentiate between a task not being present in a given pid namespace
- in which case we already print 0 - and a task having been reaped.
Note that this uses PIDTYPE_PID for the check. Technically, we could've
checked PIDTYPE_TGID since pidfds currently only refer to thread-group
leaders but if they won't anymore in the future then this check becomes
problematic without it being immediately obvious to non-experts imho. If
a thread is created via clone(CLONE_THREAD) than struct pid has a single
non-empty list pid->tasks[PIDTYPE_PID] and this pid can't be used as a
PIDTYPE_TGID meaning pid->tasks[PIDTYPE_TGID] will return NULL even
though the thread-group leader might still be very much alive. So
checking PIDTYPE_PID is fine and is easier to maintain should we ever
allow pidfds to refer to threads.
Cc: Jann Horn <jannh@google.com>
Cc: Christian Kellner <christian@kellner.me>
Cc: linux-api@vger.kernel.org
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Link: https://lore.kernel.org/r/20191017101832.5985-1-christian.brauner@ubuntu.com
Both multi_cpu_stop() and set_state() access multi_stop_data::state
racily using plain accesses. These are subject to compiler
transformations which could break the intended behaviour of the code,
and this situation is detected by KCSAN on both arm64 and x86 (splats
below).
Improve matters by using READ_ONCE() and WRITE_ONCE() to ensure that the
compiler cannot elide, replay, or tear loads and stores.
In multi_cpu_stop() the two loads of multi_stop_data::state are expected to
be a consistent value, so snapshot the value into a temporary variable to
ensure this.
The state transitions are serialized by atomic manipulation of
multi_stop_data::num_threads, and other fields in multi_stop_data are not
modified while subject to concurrent reads.
KCSAN splat on arm64:
| BUG: KCSAN: data-race in multi_cpu_stop+0xa8/0x198 and set_state+0x80/0xb0
|
| write to 0xffff00001003bd00 of 4 bytes by task 24 on cpu 3:
| set_state+0x80/0xb0
| multi_cpu_stop+0x16c/0x198
| cpu_stopper_thread+0x170/0x298
| smpboot_thread_fn+0x40c/0x560
| kthread+0x1a8/0x1b0
| ret_from_fork+0x10/0x18
|
| read to 0xffff00001003bd00 of 4 bytes by task 14 on cpu 1:
| multi_cpu_stop+0xa8/0x198
| cpu_stopper_thread+0x170/0x298
| smpboot_thread_fn+0x40c/0x560
| kthread+0x1a8/0x1b0
| ret_from_fork+0x10/0x18
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.3.0-00007-g67ab35a199f4-dirty #3
| Hardware name: linux,dummy-virt (DT)
KCSAN splat on x86:
| write to 0xffffb0bac0013e18 of 4 bytes by task 19 on cpu 2:
| set_state kernel/stop_machine.c:170 [inline]
| ack_state kernel/stop_machine.c:177 [inline]
| multi_cpu_stop+0x1a4/0x220 kernel/stop_machine.c:227
| cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
| smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
| kthread+0x1b5/0x200 kernel/kthread.c:255
| ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| read to 0xffffb0bac0013e18 of 4 bytes by task 44 on cpu 7:
| multi_cpu_stop+0xb4/0x220 kernel/stop_machine.c:213
| cpu_stopper_thread+0x19e/0x280 kernel/stop_machine.c:516
| smpboot_thread_fn+0x1a8/0x300 kernel/smpboot.c:165
| kthread+0x1b5/0x200 kernel/kthread.c:255
| ret_from_fork+0x35/0x40 arch/x86/entry/entry_64.S:352
|
| Reported by Kernel Concurrency Sanitizer on:
| CPU: 7 PID: 44 Comm: migration/7 Not tainted 5.3.0+ #1
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-1 04/01/2014
Signed-off-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20191007104536.27276-1-mark.rutland@arm.com
The option --sort=ORDER was only introduced in tar 1.28 (2014), which
is rather new and might not be available in some setups.
This patch tries to replicate the previous behaviour as closely as
possible to fix the kheaders build for older environments. It does
not produce identical archives compared to the previous version due
to minor sorting differences but produces reproducible results itself
in my tests.
Reported-by: Andreas Schwab <schwab@suse.de>
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Tested-by: Andreas Schwab <schwab@suse.de>
Tested-by: Quentin Perret <qperret@google.com>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
bpf stackmap with build-id lookup (BPF_F_STACK_BUILD_ID) can trigger A-A
deadlock on rq_lock():
rcu: INFO: rcu_sched detected stalls on CPUs/tasks:
[...]
Call Trace:
try_to_wake_up+0x1ad/0x590
wake_up_q+0x54/0x80
rwsem_wake+0x8a/0xb0
bpf_get_stack+0x13c/0x150
bpf_prog_fbdaf42eded9fe46_on_event+0x5e3/0x1000
bpf_overflow_handler+0x60/0x100
__perf_event_overflow+0x4f/0xf0
perf_swevent_overflow+0x99/0xc0
___perf_sw_event+0xe7/0x120
__schedule+0x47d/0x620
schedule+0x29/0x90
futex_wait_queue_me+0xb9/0x110
futex_wait+0x139/0x230
do_futex+0x2ac/0xa50
__x64_sys_futex+0x13c/0x180
do_syscall_64+0x42/0x100
entry_SYSCALL_64_after_hwframe+0x44/0xa9
This can be reproduced by:
1. Start a multi-thread program that does parallel mmap() and malloc();
2. taskset the program to 2 CPUs;
3. Attach bpf program to trace_sched_switch and gather stackmap with
build-id, e.g. with trace.py from bcc tools:
trace.py -U -p <pid> -s <some-bin,some-lib> t:sched:sched_switch
A sample reproducer is attached at the end.
This could also trigger deadlock with other locks that are nested with
rq_lock.
Fix this by checking whether irqs are disabled. Since rq_lock and all
other nested locks are irq safe, it is safe to do up_read() when irqs are
not disable. If the irqs are disabled, postpone up_read() in irq_work.
Fixes: 615755a77b ("bpf: extend stackmap to save binary_build_id+offset instead of address")
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191014171223.357174-1-songliubraving@fb.com
Reproducer:
============================ 8< ============================
char *filename;
void *worker(void *p)
{
void *ptr;
int fd;
char *pptr;
fd = open(filename, O_RDONLY);
if (fd < 0)
return NULL;
while (1) {
struct timespec ts = {0, 1000 + rand() % 2000};
ptr = mmap(NULL, 4096 * 64, PROT_READ, MAP_PRIVATE, fd, 0);
usleep(1);
if (ptr == MAP_FAILED) {
printf("failed to mmap\n");
break;
}
munmap(ptr, 4096 * 64);
usleep(1);
pptr = malloc(1);
usleep(1);
pptr[0] = 1;
usleep(1);
free(pptr);
usleep(1);
nanosleep(&ts, NULL);
}
close(fd);
return NULL;
}
int main(int argc, char *argv[])
{
void *ptr;
int i;
pthread_t threads[THREAD_COUNT];
if (argc < 2)
return 0;
filename = argv[1];
for (i = 0; i < THREAD_COUNT; i++) {
if (pthread_create(threads + i, NULL, worker, NULL)) {
fprintf(stderr, "Error creating thread\n");
return 0;
}
}
for (i = 0; i < THREAD_COUNT; i++)
pthread_join(threads[i], NULL);
return 0;
}
============================ 8< ============================
The __kthread_queue_delayed_work is not exported so
make it static, to avoid the following sparse warning:
kernel/kthread.c:869:6: warning: symbol '__kthread_queue_delayed_work' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull parisc fixes from Helge Deller:
- Fix a parisc-specific fallout of Christoph's
dma_set_mask_and_coherent() patches (Sven)
- Fix a vmap memory leak in ioremap()/ioremap() (Helge)
- Some minor cleanups and documentation updates (Nick, Helge)
* 'parisc-5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Remove 32-bit DMA enforcement from sba_iommu
parisc: Fix vmap memory leak in ioremap()/iounmap()
parisc: prefer __section from compiler_attributes.h
parisc: sysctl.c: Use CONFIG_PARISC instead of __hppa_ define
MAINTAINERS: Add hp_sdc drivers to parisc arch
Currently, the fdinfo file contains the Pid field which shows the
pid a given pidfd refers to in the pid namespace of the procfs
instance. If pid namespaces are configured, also show an NSpid field
for easy retrieval of the pid in all descendant pid namespaces. If
the pid namespace of the process is not a descendant of the pid
namespace of the procfs instance 0 will be shown as its first NSpid
entry and no other entries will be shown. Add a block comment to
pidfd_show_fdinfo with a detailed explanation of Pid and NSpid fields.
Co-developed-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Christian Kellner <christian@kellner.me>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20191014162034.2185-1-ckellner@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2019-10-14
The following pull-request contains BPF updates for your *net-next* tree.
12 days of development and
85 files changed, 1889 insertions(+), 1020 deletions(-)
The main changes are:
1) auto-generation of bpf_helper_defs.h, from Andrii.
2) split of bpf_helpers.h into bpf_{helpers, helper_defs, endian, tracing}.h
and move into libbpf, from Andrii.
3) Track contents of read-only maps as scalars in the verifier, from Andrii.
4) small x86 JIT optimization, from Daniel.
5) cross compilation support, from Ivan.
6) bpf flow_dissector enhancements, from Jakub and Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Followup to commit dd2261ed45 ("hrtimer: Protect lockless access
to timer->base")
lock_hrtimer_base() fetches timer->base without lock exclusion.
Compiler is allowed to read timer->base twice (even if considered dumb)
which could end up trying to lock migration_base and return
&migration_base.
base = timer->base;
if (likely(base != &migration_base)) {
/* compiler reads timer->base again, and now (base == &migration_base)
raw_spin_lock_irqsave(&base->cpu_base->lock, *flags);
if (likely(base == timer->base))
return base; /* == &migration_base ! */
Similarly the write sides must use WRITE_ONCE() to avoid store tearing.
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191008173204.180879-1-edumazet@google.com
- Removed locked down from tracefs itself and moved it to the trace
directory. Having the open functions there do the lockdown checks.
- Fixed a few races with opening an instance file and the instance being
deleted (Discovered during the locked down updates). Kept separate
from the clean up code such that they can be backported to stable
easier.
- Cleaned up and consolidated the checks done when opening a trace
file, as there were multiple checks that need to be done, and it
did not make sense having them done in each open instance.
- Fixed a regression in the record mcount code.
- Small hw_lat detector tracer fixes.
- A trace_pipe read fix due to not initializing trace_seq.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXaNhphQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6quDIAP4v08ARNdIh+r+c4AOBm3xsOuE/d9GB
I56ydnskm+x2JQD6Ap9ivXe9yDBIErFeHNtCoq7pM8YDI4YoYIB30N0GfwM=
=7oAu
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"A few tracing fixes:
- Remove lockdown from tracefs itself and moved it to the trace
directory. Have the open functions there do the lockdown checks.
- Fix a few races with opening an instance file and the instance
being deleted (Discovered during the lockdown updates). Kept
separate from the clean up code such that they can be backported to
stable easier.
- Clean up and consolidated the checks done when opening a trace
file, as there were multiple checks that need to be done, and it
did not make sense having them done in each open instance.
- Fix a regression in the record mcount code.
- Small hw_lat detector tracer fixes.
- A trace_pipe read fix due to not initializing trace_seq"
* tag 'trace-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Initialize iter->seq after zeroing in tracing_read_pipe()
tracing/hwlat: Don't ignore outer-loop duration when calculating max_latency
tracing/hwlat: Report total time spent in all NMIs during the sample
recordmcount: Fix nop_mcount() function
tracing: Do not create tracefs files if tracefs lockdown is in effect
tracing: Add locked_down checks to the open calls of files created for tracefs
tracing: Add tracing_check_open_get_tr()
tracing: Have trace events system open call tracing_open_generic_tr()
tracing: Get trace_array reference for available_tracers files
ftrace: Get a reference counter for the trace_array on filter files
tracefs: Revert ccbd54ff54 ("tracefs: Restrict tracefs when the kernel is locked down")
A customer reported the following softlockup:
[899688.160002] NMI watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [test.sh:16464]
[899688.160002] CPU: 0 PID: 16464 Comm: test.sh Not tainted 4.12.14-6.23-azure #1 SLE12-SP4
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] Kernel panic - not syncing: softlockup: hung tasks
[899688.160002] RIP: 0010:up_write+0x1a/0x30
[899688.160002] RSP: 0018:ffffa86784d4fde8 EFLAGS: 00000257 ORIG_RAX: ffffffffffffff12
[899688.160002] RAX: ffffffff970fea00 RBX: 0000000000000001 RCX: 0000000000000000
[899688.160002] RDX: ffffffff00000001 RSI: 0000000000000080 RDI: ffffffff970fea00
[899688.160002] RBP: ffffffffffffffff R08: ffffffffffffffff R09: 0000000000000000
[899688.160002] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8b59014720d8
[899688.160002] R13: ffff8b59014720c0 R14: ffff8b5901471090 R15: ffff8b5901470000
[899688.160002] tracing_read_pipe+0x336/0x3c0
[899688.160002] __vfs_read+0x26/0x140
[899688.160002] vfs_read+0x87/0x130
[899688.160002] SyS_read+0x42/0x90
[899688.160002] do_syscall_64+0x74/0x160
It caught the process in the middle of trace_access_unlock(). There is
no loop. So, it must be looping in the caller tracing_read_pipe()
via the "waitagain" label.
Crashdump analyze uncovered that iter->seq was completely zeroed
at this point, including iter->seq.seq.size. It means that
print_trace_line() was never able to print anything and
there was no forward progress.
The culprit seems to be in the code:
/* reset all but tr, trace, and overruns */
memset(&iter->seq, 0,
sizeof(struct trace_iterator) -
offsetof(struct trace_iterator, seq));
It was added by the commit 53d0aa7730 ("ftrace:
add logic to record overruns"). It was v2.6.27-rc1.
It was the time when iter->seq looked like:
struct trace_seq {
unsigned char buffer[PAGE_SIZE];
unsigned int len;
};
There was no "size" variable and zeroing was perfectly fine.
The solution is to reinitialize the structure after or without
zeroing.
Link: http://lkml.kernel.org/r/20191011142134.11997-1-pmladek@suse.com
Signed-off-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
max_latency is intended to record the maximum ever observed hardware
latency, which may occur in either part of the loop (inner/outer). So
we need to also consider the outer-loop sample when updating
max_latency.
Link: http://lkml.kernel.org/r/157073345463.17189.18124025522664682811.stgit@srivatsa-ubuntu
Fixes: e7c15cd8a1 ("tracing: Added hardware latency tracer")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
nmi_total_ts is supposed to record the total time spent in *all* NMIs
that occur on the given CPU during the (active portion of the)
sampling window. However, the code seems to be overwriting this
variable for each NMI, thereby only recording the time spent in the
most recent NMI. Fix it by accumulating the duration instead.
Link: http://lkml.kernel.org/r/157073343544.17189.13911783866738671133.stgit@srivatsa-ubuntu
Fixes: 7b2c862501 ("tracing: Add NMI tracing in hwlat detector")
Cc: stable@vger.kernel.org
Signed-off-by: Srivatsa S. Bhat (VMware) <srivatsa@csail.mit.edu>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Added various checks on open tracefs calls to see if tracefs is in lockdown
mode, and if so, to return -EPERM.
Note, the event format files (which are basically standard on all machines)
as well as the enabled_functions file (which shows what is currently being
traced) are not lockde down. Perhaps they should be, but it seems counter
intuitive to lockdown information to help you know if the system has been
modified.
Link: http://lkml.kernel.org/r/CAHk-=wj7fGPKUspr579Cii-w_y60PtRaiDgKuxVtBAMK0VNNkA@mail.gmail.com
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Currently, most files in the tracefs directory test if tracing_disabled is
set. If so, it should return -ENODEV. The tracing_disabled is called when
tracing is found to be broken. Originally it was done in case the ring
buffer was found to be corrupted, and we wanted to prevent reading it from
crashing the kernel. But it's also called if a tracing selftest fails on
boot. It's a one way switch. That is, once it is triggered, tracing is
disabled until reboot.
As most tracefs files can also be used by instances in the tracefs
directory, they need to be carefully done. Each instance has a trace_array
associated to it, and when the instance is removed, the trace_array is
freed. But if an instance is opened with a reference to the trace_array,
then it requires looking up the trace_array to get its ref counter (as there
could be a race with it being deleted and the open itself). Once it is
found, a reference is added to prevent the instance from being removed (and
the trace_array associated with it freed).
Combine the two checks (tracing_disabled and trace_array_get()) into a
single helper function. This will also make it easier to add lockdown to
tracefs later.
Link: http://lkml.kernel.org/r/20191011135458.7399da44@gandalf.local.home
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Instead of having the trace events system open call open code the taking of
the trace_array descriptor (with trace_array_get()) and then calling
trace_open_generic(), have it use the tracing_open_generic_tr() that does
the combination of the two. This requires making tracing_open_generic_tr()
global.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As instances may have different tracers available, we need to look at the
trace_array descriptor that shows the list of the available tracers for the
instance. But there's a race between opening the file and an admin
deleting the instance. The trace_array_get() needs to be called before
accessing the trace_array.
Cc: stable@vger.kernel.org
Fixes: 607e2ea167 ("tracing: Set up infrastructure to allow tracers for instances")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The ftrace set_ftrace_filter and set_ftrace_notrace files are specific for
an instance now. They need to take a reference to the instance otherwise
there could be a race between accessing the files and deleting the instance.
It wasn't until the :mod: caching where these file operations started
referencing the trace_array directly.
Cc: stable@vger.kernel.org
Fixes: 673feb9d76 ("ftrace: Add :mod: caching infrastructure to trace_array")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull scheduler fixes from Ingo Molnar:
"Two fixes: a guest-cputime accounting fix, and a cgroup bandwidth
quota precision fix"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/vtime: Fix guest/system mis-accounting on task switch
sched/fair: Scale bandwidth quota and period without losing quota/period ratio precision
Pull perf fixes from Ingo Molnar:
"Mostly tooling fixes, but also a couple of updates for new Intel
models (which are technically hw-enablement, but to users it's a fix
to perf behavior on those new CPUs - hope this is fine), an AUX
inheritance fix, event time-sharing fix, and a fix for lost non-perf
NMI events on AMD systems"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
perf/x86/cstate: Add Tiger Lake CPU support
perf/x86/msr: Add Tiger Lake CPU support
perf/x86/intel: Add Tiger Lake CPU support
perf/x86/cstate: Update C-state counters for Ice Lake
perf/x86/msr: Add new CPU model numbers for Ice Lake
perf/x86/cstate: Add Comet Lake CPU support
perf/x86/msr: Add Comet Lake CPU support
perf/x86/intel: Add Comet Lake CPU support
perf/x86/amd: Change/fix NMI latency mitigation to use a timestamp
perf/core: Fix corner case in perf_rotate_context()
perf/core: Rework memory accounting in perf_mmap()
perf/core: Fix inheritance of aux_output groups
perf annotate: Don't return -1 for error when doing BPF disassembly
perf annotate: Return appropriate error code for allocation failures
perf annotate: Fix arch specific ->init() failure errors
perf annotate: Propagate the symbol__annotate() error return
perf annotate: Fix the signedness of failure returns
perf annotate: Propagate perf_env__arch() error
perf evsel: Fall back to global 'perf_env' in perf_evsel__env()
perf tools: Propagate get_cpuid() error
...
Fix "warning: cast to pointer from integer of different size" when
casting u64 addr to void *.
Fixes: a23740ec43 ("bpf: Track contents of read-only maps as scalars")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20191011172053.2980619-1-andriin@fb.com
ptrace_stop() does preempt_enable_no_resched() to avoid the preemption,
but after that cgroup_enter_frozen() does spin_lock/unlock and this adds
another preemption point.
Reported-and-tested-by: Bruce Ashfield <bruce.ashfield@gmail.com>
Fixes: 76f969e894 ("cgroup: cgroup v2 freezer")
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Maps that are read-only both from BPF program side and user space side
have their contents constant, so verifier can track referenced values
precisely and use that knowledge for dead code elimination, branch
pruning, etc. This patch teaches BPF verifier how to do this.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20191009201458.2679171-2-andriin@fb.com
This allows the seccomp notifier to continue a syscall. A positive
discussion about this feature was triggered by a post to the
ksummit-discuss mailing list (cf. [3]) and took place during KSummit
(cf. [1]) and again at the containers/checkpoint-restore
micro-conference at Linux Plumbers.
Recently we landed seccomp support for SECCOMP_RET_USER_NOTIF (cf. [4])
which enables a process (watchee) to retrieve an fd for its seccomp
filter. This fd can then be handed to another (usually more privileged)
process (watcher). The watcher will then be able to receive seccomp
messages about the syscalls having been performed by the watchee.
This feature is heavily used in some userspace workloads. For example,
it is currently used to intercept mknod() syscalls in user namespaces
aka in containers.
The mknod() syscall can be easily filtered based on dev_t. This allows
us to only intercept a very specific subset of mknod() syscalls.
Furthermore, mknod() is not possible in user namespaces toto coelo and
so intercepting and denying syscalls that are not in the whitelist on
accident is not a big deal. The watchee won't notice a difference.
In contrast to mknod(), a lot of other syscall we intercept (e.g.
setxattr()) cannot be easily filtered like mknod() because they have
pointer arguments. Additionally, some of them might actually succeed in
user namespaces (e.g. setxattr() for all "user.*" xattrs). Since we
currently cannot tell seccomp to continue from a user notifier we are
stuck with performing all of the syscalls in lieu of the container. This
is a huge security liability since it is extremely difficult to
correctly assume all of the necessary privileges of the calling task
such that the syscall can be successfully emulated without escaping
other additional security restrictions (think missing CAP_MKNOD for
mknod(), or MS_NODEV on a filesystem etc.). This can be solved by
telling seccomp to resume the syscall.
One thing that came up in the discussion was the problem that another
thread could change the memory after userspace has decided to let the
syscall continue which is a well known TOCTOU with seccomp which is
present in other ways already.
The discussion showed that this feature is already very useful for any
syscall without pointer arguments. For any accidentally intercepted
non-pointer syscall it is safe to continue.
For syscalls with pointer arguments there is a race but for any cautious
userspace and the main usec cases the race doesn't matter. The notifier
is intended to be used in a scenario where a more privileged watcher
supervises the syscalls of lesser privileged watchee to allow it to get
around kernel-enforced limitations by performing the syscall for it
whenever deemed save by the watcher. Hence, if a user tricks the watcher
into allowing a syscall they will either get a deny based on
kernel-enforced restrictions later or they will have changed the
arguments in such a way that they manage to perform a syscall with
arguments that they would've been allowed to do anyway.
In general, it is good to point out again, that the notifier fd was not
intended to allow userspace to implement a security policy but rather to
work around kernel security mechanisms in cases where the watcher knows
that a given action is safe to perform.
/* References */
[1]: https://linuxplumbersconf.org/event/4/contributions/560
[2]: https://linuxplumbersconf.org/event/4/contributions/477
[3]: https://lore.kernel.org/r/20190719093538.dhyopljyr5ns33qx@brauner.io
[4]: commit 6a21cc50f0 ("seccomp: add a return code to trap to userspace")
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Tycho Andersen <tycho@tycho.ws>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
CC: Tyler Hicks <tyhicks@canonical.com>
Link: https://lore.kernel.org/r/20190920083007.11475-2-christian.brauner@ubuntu.com
Signed-off-by: Kees Cook <keescook@chromium.org>
In kdb when you do 'btc' (back trace on CPU) it doesn't necessarily
give you the right info. Specifically on many architectures
(including arm64, where I tested) you can't dump the stack of a
"running" process that isn't the process running on the current CPU.
This can be seen by this:
echo SOFTLOCKUP > /sys/kernel/debug/provoke-crash/DIRECT
# wait 2 seconds
<sysrq>g
Here's what I see now on rk3399-gru-kevin. I see the stack crawl for
the CPU that handled the sysrq but everything else just shows me stuck
in __switch_to() which is bogus:
======
[0]kdb> btc
btc: cpu status: Currently on cpu 0
Available cpus: 0, 1-3(I), 4, 5(I)
Stack traceback for pid 0
0xffffff801101a9c0 0 0 1 0 R 0xffffff801101b3b0 *swapper/0
Call trace:
dump_backtrace+0x0/0x138
...
kgdb_compiled_brk_fn+0x34/0x44
...
sysrq_handle_dbg+0x34/0x5c
Stack traceback for pid 0
0xffffffc0f175a040 0 0 1 1 I 0xffffffc0f175aa30 swapper/1
Call trace:
__switch_to+0x1e4/0x240
0xffffffc0f65616c0
Stack traceback for pid 0
0xffffffc0f175d040 0 0 1 2 I 0xffffffc0f175da30 swapper/2
Call trace:
__switch_to+0x1e4/0x240
0xffffffc0f65806c0
Stack traceback for pid 0
0xffffffc0f175b040 0 0 1 3 I 0xffffffc0f175ba30 swapper/3
Call trace:
__switch_to+0x1e4/0x240
0xffffffc0f659f6c0
Stack traceback for pid 1474
0xffffffc0dde8b040 1474 727 1 4 R 0xffffffc0dde8ba30 bash
Call trace:
__switch_to+0x1e4/0x240
__schedule+0x464/0x618
0xffffffc0dde8b040
Stack traceback for pid 0
0xffffffc0f17b0040 0 0 1 5 I 0xffffffc0f17b0a30 swapper/5
Call trace:
__switch_to+0x1e4/0x240
0xffffffc0f65dd6c0
===
The problem is that 'btc' eventually boils down to
show_stack(task_struct, NULL);
...and show_stack() doesn't work for "running" CPUs because their
registers haven't been stashed.
On x86 things might work better (I haven't tested) because kdb has a
special case for x86 in kdb_show_stack() where it passes the stack
pointer to show_stack(). This wouldn't work on arm64 where the stack
crawling function seems needs the "fp" and "pc", not the "sp" which is
presumably why arm64's show_stack() function totally ignores the "sp"
parameter.
NOTE: we _can_ get a good stack dump for all the cpus if we manually
switch each one to the kdb master and do a back trace. AKA:
cpu 4
bt
...will give the expected trace. That's because now arm64's
dump_backtrace will now see that "tsk == current" and go through a
different path.
In this patch I fix the problems by catching a request to stack crawl
a task that's running on a CPU and then I ask that CPU to do the stack
crawl.
NOTE: this will (presumably) change what stack crawls are printed for
x86 machines. Now kdb functions will show up in the stack crawl.
Presumably this is OK but if it's not we can go back and add a special
case for x86 again.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
I noticed that when I did "btc <cpu>" and the CPU I passed in hadn't
rounded up that I'd crash. I was going to copy the same fix from
commit 162bc7f5af ("kdb: Don't back trace on a cpu that didn't round
up") into the "not all the CPUs" case, but decided it'd be better to
clean things up a little bit.
This consolidates the two code paths. It is _slightly_ wasteful in in
that the checks for "cpu" being too small or being offline isn't
really needed when we're iterating over all online CPUs, but that
really shouldn't hurt. Better to have the same code path.
While at it, eliminate at least one slightly ugly (and totally
needless) recursive use of kdb_parse().
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
The kdb_bt1() had a mysterious "argcount" parameter passed in (always
the number 5, by the way) and never used. Presumably this is just old
cruft. Remove it. While at it, upgrade the btaprompt parameter to a
full fledged bool instead of an int.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
From doing a 'git log --patch kernel/debug', it looks as if DCPU_SSTEP
has never been used. Presumably it used to be used back when kgdb was
out of tree and nobody thought to delete the definition when the usage
went away. Delete.
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Acked-by: Jason Wessel <jason.wessel@windriver.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
Include the <linux/runtime_pm.h> for the definition of
pm_wq to avoid the following warning:
kernel/power/main.c:890:25: warning: symbol 'pm_wq' was not declared. Should it be static?
Signed-off-by: Ben Dooks <ben.dooks@codethink.co.uk>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In perf_rotate_context(), when the first cpu flexible event fail to
schedule, cpu_rotate is 1, while cpu_event is NULL. Since cpu_event is
NULL, perf_rotate_context will _NOT_ call cpu_ctx_sched_out(), thus
cpuctx->ctx.is_active will have EVENT_FLEXIBLE set. Then, the next
perf_event_sched_in() will skip all cpu flexible events because of the
EVENT_FLEXIBLE bit.
In the next call of perf_rotate_context(), cpu_rotate stays 1, and
cpu_event stays NULL, so this process repeats. The end result is, flexible
events on this cpu will not be scheduled (until another event being added
to the cpuctx).
Here is an easy repro of this issue. On Intel CPUs, where ref-cycles
could only use one counter, run one pinned event for ref-cycles, one
flexible event for ref-cycles, and one flexible event for cycles. The
flexible ref-cycles is never scheduled, which is expected. However,
because of this issue, the cycles event is never scheduled either.
$ perf stat -e ref-cycles:D,ref-cycles,cycles -C 5 -I 1000
time counts unit events
1.000152973 15,412,480 ref-cycles:D
1.000152973 <not counted> ref-cycles (0.00%)
1.000152973 <not counted> cycles (0.00%)
2.000486957 18,263,120 ref-cycles:D
2.000486957 <not counted> ref-cycles (0.00%)
2.000486957 <not counted> cycles (0.00%)
To fix this, when the flexible_active list is empty, try rotate the
first event in the flexible_groups. Also, rename ctx_first_active() to
ctx_event_to_rotate(), which is more accurate.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <kernel-team@fb.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sasha Levin <sashal@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 8d5bce0c37 ("perf/core: Optimize perf_rotate_context() event scheduling")
Link: https://lkml.kernel.org/r/20191008165949.920548-1-songliubraving@fb.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On context switch we are locking the vtime seqcount of the scheduling-out
task twice:
* On vtime_task_switch_common(), when we flush the pending vtime through
vtime_account_system()
* On arch_vtime_task_switch() to reset the vtime state.
This is pointless as these actions can be performed without the need
to unlock/lock in the middle. The reason these steps are separated is to
consolidate a very small amount of common code between
CONFIG_VIRT_CPU_ACCOUNTING_GEN and CONFIG_VIRT_CPU_ACCOUNTING_NATIVE.
Performance in this fast path is definitely a priority over artificial
code factorization so split the task switch code between GEN and
NATIVE and mutualize the parts than can run under a single seqcount
locked block.
As a side effect, vtime_account_idle() becomes included in the seqcount
protection. This happens to be a welcome preparation in order to
properly support kcpustat under vtime in the future and fetch
CPUTIME_IDLE without race.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191003161745.28464-3-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
vtime_account_system() decides if we need to account the time to the
system (__vtime_account_system()) or to the guest (vtime_account_guest()).
So this function is a misnomer as we are on a higher level than
"system". All we know when we call that function is that we are
accounting kernel cputime. Whether it belongs to guest or system time
is a lower level detail.
Rename this function to vtime_account_kernel(). This will clarify things
and avoid too many underscored vtime_account_system() versions.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Link: https://lkml.kernel.org/r/20191003161745.28464-2-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
vtime_account_system() assumes that the target task to account cputime
to is always the current task. This is most often true indeed except on
task switch where we call:
vtime_common_task_switch(prev)
vtime_account_system(prev)
Here prev is the scheduling-out task where we account the cputime to. It
doesn't match current that is already the scheduling-in task at this
stage of the context switch.
So we end up checking the wrong task flags to determine if we are
accounting guest or system time to the previous task.
As a result the wrong task is used to check if the target is running in
guest mode. We may then spuriously account or leak either system or
guest time on task switch.
Fix this assumption and also turn vtime_guest_enter/exit() to use the
task passed in parameter as well to avoid future similar issues.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Wanpeng Li <wanpengli@tencent.com>
Fixes: 2a42eb9594 ("sched/cputime: Accumulate vtime on top of nsec clocksource")
Link: https://lkml.kernel.org/r/20190925214242.21873-1-frederic@kernel.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The quota/period ratio is used to ensure a child task group won't get
more bandwidth than the parent task group, and is calculated as:
normalized_cfs_quota() = [(quota_us << 20) / period_us]
If the quota/period ratio was changed during this scaling due to
precision loss, it will cause inconsistency between parent and child
task groups.
See below example:
A userspace container manager (kubelet) does three operations:
1) Create a parent cgroup, set quota to 1,000us and period to 10,000us.
2) Create a few children cgroups.
3) Set quota to 1,000us and period to 10,000us on a child cgroup.
These operations are expected to succeed. However, if the scaling of
147/128 happens before step 3, quota and period of the parent cgroup
will be changed:
new_quota: 1148437ns, 1148us
new_period: 11484375ns, 11484us
And when step 3 comes in, the ratio of the child cgroup will be
104857, which will be larger than the parent cgroup ratio (104821),
and will fail.
Scaling them by a factor of 2 will fix the problem.
Tested-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Xuewei Zhang <xueweiz@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Phil Auld <pauld@redhat.com>
Cc: Anton Blanchard <anton@ozlabs.org>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Fixes: 2e8e192263 ("sched/fair: Limit sched_cfs_period_timer() loop to avoid hard lockup")
Link: https://lkml.kernel.org/r/20191004001243.140897-1-xueweiz@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Merge misc fixes from Andrew Morton:
"The usual shower of hotfixes.
Chris's memcg patches aren't actually fixes - they're mature but a few
niggling review issues were late to arrive.
The ocfs2 fixes are quite old - those took some time to get reviewer
attention.
Subsystems affected by this patch series: ocfs2, hotfixes, mm/memcg,
mm/slab-generic"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm, sl[aou]b: guarantee natural alignment for kmalloc(power-of-two)
mm, sl[ou]b: improve memory accounting
mm, memcg: make scan aggression always exclude protection
mm, memcg: make memory.emin the baseline for utilisation determination
mm, memcg: proportional memory.{low,min} reclaim
mm/vmpressure.c: fix a signedness bug in vmpressure_register_event()
mm/page_alloc.c: fix a crash in free_pages_prepare()
mm/z3fold.c: claim page in the beginning of free
kernel/sysctl.c: do not override max_threads provided by userspace
memcg: only record foreign writebacks with dirty pages when memcg is not disabled
mm: fix -Wmissing-prototypes warnings
writeback: fix use-after-free in finish_writeback_work()
mm/memremap: drop unused SECTION_SIZE and SECTION_MASK
panic: ensure preemption is disabled during panic()
fs: ocfs2: fix a possible null-pointer dereference in ocfs2_info_scan_inode_alloc()
fs: ocfs2: fix a possible null-pointer dereference in ocfs2_write_end_nolock()
fs: ocfs2: fix possible null-pointer dereferences in ocfs2_xa_prepare_entry()
ocfs2: clear zero in unaligned direct IO
Partially revert 16db3d3f11 ("kernel/sysctl.c: threads-max observe
limits") because the patch is causing a regression to any workload which
needs to override the auto-tuning of the limit provided by kernel.
set_max_threads is implementing a boot time guesstimate to provide a
sensible limit of the concurrently running threads so that runaways will
not deplete all the memory. This is a good thing in general but there
are workloads which might need to increase this limit for an application
to run (reportedly WebSpher MQ is affected) and that is simply not
possible after the mentioned change. It is also very dubious to
override an admin decision by an estimation that doesn't have any direct
relation to correctness of the kernel operation.
Fix this by dropping set_max_threads from sysctl_max_threads so any
value is accepted as long as it fits into MAX_THREADS which is important
to check because allowing more threads could break internal robust futex
restriction. While at it, do not use MIN_THREADS as the lower boundary
because it is also only a heuristic for automatic estimation and admin
might have a good reason to stop new threads to be created even when
below this limit.
This became more severe when we switched x86 from 4k to 8k kernel
stacks. Starting since 6538b8ea88 ("x86_64: expand kernel stack to
16K") (3.16) we use THREAD_SIZE_ORDER = 2 and that halved the auto-tuned
value.
In the particular case
3.12
kernel.threads-max = 515561
4.4
kernel.threads-max = 200000
Neither of the two values is really insane on 32GB machine.
I am not sure we want/need to tune the max_thread value further. If
anything the tuning should be removed altogether if proven not useful in
general. But we definitely need a way to override this auto-tuning.
Link: http://lkml.kernel.org/r/20190922065801.GB18814@dhcp22.suse.cz
Fixes: 16db3d3f11 ("kernel/sysctl.c: threads-max observe limits")
Signed-off-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Heinrich Schuchardt <xypron.glpk@gmx.de>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Calling 'panic()' on a kernel with CONFIG_PREEMPT=y can leave the
calling CPU in an infinite loop, but with interrupts and preemption
enabled. From this state, userspace can continue to be scheduled,
despite the system being "dead" as far as the kernel is concerned.
This is easily reproducible on arm64 when booting with "nosmp" on the
command line; a couple of shell scripts print out a periodic "Ping"
message whilst another triggers a crash by writing to
/proc/sysrq-trigger:
| sysrq: Trigger a crash
| Kernel panic - not syncing: sysrq triggered crash
| CPU: 0 PID: 1 Comm: init Not tainted 5.2.15 #1
| Hardware name: linux,dummy-virt (DT)
| Call trace:
| dump_backtrace+0x0/0x148
| show_stack+0x14/0x20
| dump_stack+0xa0/0xc4
| panic+0x140/0x32c
| sysrq_handle_reboot+0x0/0x20
| __handle_sysrq+0x124/0x190
| write_sysrq_trigger+0x64/0x88
| proc_reg_write+0x60/0xa8
| __vfs_write+0x18/0x40
| vfs_write+0xa4/0x1b8
| ksys_write+0x64/0xf0
| __arm64_sys_write+0x14/0x20
| el0_svc_common.constprop.0+0xb0/0x168
| el0_svc_handler+0x28/0x78
| el0_svc+0x8/0xc
| Kernel Offset: disabled
| CPU features: 0x0002,24002004
| Memory Limit: none
| ---[ end Kernel panic - not syncing: sysrq triggered crash ]---
| Ping 2!
| Ping 1!
| Ping 1!
| Ping 2!
The issue can also be triggered on x86 kernels if CONFIG_SMP=n,
otherwise local interrupts are disabled in 'smp_send_stop()'.
Disable preemption in 'panic()' before re-enabling interrupts.
Link: http://lkml.kernel.org/r/20191002123538.22609-1-will@kernel.org
Link: https://lore.kernel.org/r/BX1W47JXPMR8.58IYW53H6M5N@dragonstone
Signed-off-by: Will Deacon <will@kernel.org>
Reported-by: Xogium <contact@xogium.me>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Feng Tang <feng.tang@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Commit:
ab43762ef0 ("perf: Allow normal events to output AUX data")
forgets to configure aux_output relation in the inherited groups, which
results in child PEBS events forever failing to schedule.
Fix this by setting up the AUX output link in the inheritance path.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20191004125729.32397-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
There are reports of users who use thread migrations between cgroups and
they report performance drop after d59cfc09c3 ("sched, cgroup: replace
signal_struct->group_rwsem with a global percpu_rwsem"). The effect is
pronounced on machines with more CPUs.
The migration is affected by forking noise happening in the background,
after the mentioned commit a migrating thread must wait for all
(forking) processes on the system, not only of its threadgroup.
There are several places that need to synchronize with migration:
a) do_exit,
b) de_thread,
c) copy_process,
d) cgroup_update_dfl_csses,
e) parallel migration (cgroup_{proc,thread}s_write).
In the case of self-migrating thread, we relax the synchronization on
cgroup_threadgroup_rwsem to avoid the cost of waiting. d) and e) are
excluded with cgroup_mutex, c) does not matter in case of single thread
migration and the executing thread cannot exec(2) or exit(2) while it is
writing into cgroup.threads. In case of do_exit because of signal
delivery, we either exit before the migration or finish the migration
(of not yet PF_EXITING thread) and die afterwards.
This patch handles only the case of self-migration by writing "0" into
cgroup.threads. For simplicity, we always take cgroup_threadgroup_rwsem
with numeric PIDs.
This change improves migration dependent workload performance similar
to per-signal_struct state.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
We no longer take cgroup_mutex in cgroup_exit and the exiting tasks are
not moved to init_css_set, reflect that in several comments to prevent
confusion.
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Like commit 13d82fb77a ("cgroup: short-circuit cset_cgroup_from_root() on
the default hierarchy"), short-circuit current_cgns_cgroup_from_root() on
the default hierarchy.
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
- revert an incorret hunk from a patch that caused problems
on various arm boards (Andrey Smirnov)
-----BEGIN PGP SIGNATURE-----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=kS6W
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping regression fix from Christoph Hellwig:
"Revert an incorret hunk from a patch that caused problems on various
arm boards (Andrey Smirnov)"
* tag 'dma-mapping-5.4-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: fix false positive warnings in dma_common_free_remap()
This reverts commit 85fbd722ad.
The commit was added as a quick band-aid for a hang that happened when a
block device was removed during system suspend. Now that bdi_wq is not
freezable anymore the hang should not be possible and we can get rid of
this hack by reverting it.
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
- remove unneeded ar-option and KBUILD_ARFLAGS
- remove long-deprecated SUBDIRS
- fix modpost to suppress false-positive warnings for UML builds
- fix namespace.pl to handle relative paths to ${objtree}, ${srctree}
- make setlocalversion work for /bin/sh
- make header archive reproducible
- fix some Makefiles and documents
-----BEGIN PGP SIGNATURE-----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=fSXc
-----END PGP SIGNATURE-----
Merge tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild fixes from Masahiro Yamada:
- remove unneeded ar-option and KBUILD_ARFLAGS
- remove long-deprecated SUBDIRS
- fix modpost to suppress false-positive warnings for UML builds
- fix namespace.pl to handle relative paths to ${objtree}, ${srctree}
- make setlocalversion work for /bin/sh
- make header archive reproducible
- fix some Makefiles and documents
* tag 'kbuild-fixes-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kheaders: make headers archive reproducible
kbuild: update compile-test header list for v5.4-rc2
kbuild: two minor updates for Documentation/kbuild/modules.rst
scripts/setlocalversion: clear local variable to make it work for sh
namespace: fix namespace.pl script to support relative paths
video/logo: do not generate unneeded logo C files
video/logo: remove unneeded *.o pattern from clean-files
integrity: remove pointless subdir-$(CONFIG_...)
integrity: remove unneeded, broken attempt to add -fshort-wchar
modpost: fix static EXPORT_SYMBOL warnings for UML build
kbuild: correct formatting of header in kbuild module docs
kbuild: remove SUBDIRS support
kbuild: remove ar-option and KBUILD_ARFLAGS
Including rwlock.h directly will cause kernel builds to fail
if CONFIG_PREEMPT_RT is defined. The correct header file
(rwlock_rt.h OR rwlock.h) will be included by spinlock.h which
is included by locktorture.c anyway.
Remove the include of linux/rwlock.h.
Signed-off-by: Wolfgang M. Reimer <linuxball@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_torture_fwd_prog_nr() tests the ability of RCU to tolerate
in-kernel busy loops. It invokes rcu_torture_fwd_prog_cond_resched()
within its delay loop, which, in PREEMPT && NO_HZ_FULL kernels results
in the occasional direct call to schedule(). Now, this direct call to
schedule() is appropriate for call_rcu() flood testing, in which either
the kernel should restrain itself or userspace transitions will supply
the needed restraint. But in pure in-kernel loops, the occasional
cond_resched() should do the job.
This commit therefore makes rcu_torture_fwd_prog_nr() use cond_resched()
instead of rcu_torture_fwd_prog_cond_resched() in order to increase the
brutality of this aspect of rcutorture testing.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, each of six different types of failure triggers a
single WARN_ON_ONCE(), and it is then necessary to stare at the
rcu_torture_stats(), Reader Pipe, and Reader Batch lines looking for
inappropriately non-zero values. This can be annoying and error-prone,
so this commit provides a separate WARN_ON_ONCE() for each of the
six error conditions and adds short comments to each to ease error
identification.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The variable rcu_perf_writer_state is declared and initialized,
but is never actually referenced. Remove it to clean code.
Signed-off-by: Ethan Hansen <1ethanhansen@gmail.com>
[ paulmck: Also removed unused macros assigned to that variable. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The strncmp() function is error-prone because it is easy to get the
length wrong, especially if the string is subject to change, especially
given the need to account for the terminating nul byte. This commit
therefore substitutes the newly introduced str_has_prefix(), which
does not require a separately specified length.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The function rcutorture_record_progress() is declared in rcu.h, but is
never used. This commit therefore removes rcutorture_record_progress()
to clean code.
Signed-off-by: Ethan Hansen <1ethanhansen@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
During an actual call_rcu() flood, there would be frequent trips to
userspace (in-kernel call_rcu() floods must be otherwise housebroken).
Userspace execution on nohz_full CPUs implies an RCU dyntick idle/not-idle
transition pair, so this commit adds emulation of that pair.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
CPU-hotplug removal operations run the multi_cpu_stop() function, which
relies on the scheduler to gain control from whatever is running on the
various online CPUs, including any nohz_full CPUs running long loops in
kernel-mode code. Lack of the scheduler-clock interrupt on such CPUs
can delay multi_cpu_stop() for several minutes and can also result in
RCU CPU stall warnings. This commit therefore causes CPU-hotplug removal
operations to enable the scheduler-clock interrupt on all online CPUs.
[ paulmck: Apply Joel Fernandes TICK_DEP_MASK_RCU->TICK_DEP_BIT_RCU fix. ]
[ paulmck: Apply simplifications suggested by Frederic Weisbecker. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
When multi_cpu_stop() loops waiting for other tasks, it can trigger an RCU
CPU stall warning. This can be misleading because what is instead needed
is information on whatever task is blocking multi_cpu_stop(). This commit
therefore inserts an RCU quiescent state into the multi_cpu_stop()
function's waitloop.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Readers and callback flooders in the rcutorture stress-test suite run for
extended time periods by design. They do take pains to relinquish the
CPU from time to time, but in some cases this relies on the scheduler
being active, which in turn relies on the scheduler-clock interrupt
firing from time to time.
This commit therefore forces scheduling-clock interrupts within
these loops. While in the area, this commit also prevents
rcu_torture_reader()'s occasional timed sleeps from delaying shutdown.
[ paulmck: Apply Joel Fernandes TICK_DEP_MASK_RCU->TICK_DEP_BIT_RCU fix. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Callback invocation can run for a significant time period, and within
CONFIG_NO_HZ_FULL=y kernels, this period will be devoid of scheduler-clock
interrupts. In-kernel execution without such interrupts can cause all
manner of malfunction, with RCU CPU stall warnings being but one result.
This commit therefore forces scheduling-clock interrupts on whenever more
than a few RCU callbacks are invoked. Because offloaded callback invocation
can be preempted, this forcing is withdrawn on each context switch. This
in turn requires that the loop invoking RCU callbacks reiterate the forcing
periodically.
[ paulmck: Apply Joel Fernandes TICK_DEP_MASK_RCU->TICK_DEP_BIT_RCU fix. ]
[ paulmck: Remove NO_HZ_FULL check per Frederic Weisbecker feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
It turns out that rcutorture needs to ensure that the scheduling-clock
interrupt is enabled in CONFIG_NO_HZ_FULL kernels before starting on
CPU-bound in-kernel processing. This commit therefore exports
tick_nohz_dep_set_task(), tick_nohz_dep_clear_task(), and
tick_nohz_full_setup() to GPL kernel modules.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
If a nohz_full CPU is looping in the kernel, the scheduling-clock tick
might nevertheless remain disabled. In !PREEMPT kernels, this can
prevent RCU's attempts to enlist the aid of that CPU's executions of
cond_resched(), which can in turn result in an arbitrarily delayed grace
period and thus an OOM. RCU therefore needs a way to enable a holdout
nohz_full CPU's scheduler-clock interrupt.
This commit therefore provides a new TICK_DEP_BIT_RCU value which RCU can
pass to tick_dep_set_cpu() and friends to force on the scheduler-clock
interrupt for a specified CPU or task. In some cases, rcutorture needs
to turn on the scheduler-clock tick, so this commit also exports the
relevant symbols to GPL-licensed modules.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In commit 43d8ce9d65 ("Provide in-kernel headers to make
extending kernel easier") a new mechanism was introduced, for kernels
>=5.2, which embeds the kernel headers in the kernel image or a module
and exposes them in procfs for use by userland tools.
The archive containing the header files has nondeterminism caused by
header files metadata. This patch normalizes the metadata and utilizes
KBUILD_BUILD_TIMESTAMP if provided and otherwise falls back to the
default behaviour.
In commit f7b101d330 ("kheaders: Move from proc to sysfs") it was
modified to use sysfs and the script for generation of the archive was
renamed to what is being patched.
Signed-off-by: Dmitry Goldin <dgoldin+lkml@protonmail.ch>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXZZIgQAKCRCRxhvAZXjc
orNOAP98B2nmoxvq8d5Z6PhoyTBC5NIUuJ5h2YMwcX/hAaj5uQEA58NTKtPmOPDR
2ffUFFerGZ2+brlHgACa0ZKdH27TjAA=
=QryD
-----END PGP SIGNATURE-----
Merge tag 'copy-struct-from-user-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull copy_struct_from_user() helper from Christian Brauner:
"This contains the copy_struct_from_user() helper which got split out
from the openat2() patchset. It is a generic interface designed to
copy a struct from userspace.
The helper will be especially useful for structs versioned by size of
which we have quite a few. This allows for backwards compatibility,
i.e. an extended struct can be passed to an older kernel, or a legacy
struct can be passed to a newer kernel. For the first case (extended
struct, older kernel) the new fields in an extended struct can be set
to zero and the struct safely passed to an older kernel.
The most obvious benefit is that this helper lets us get rid of
duplicate code present in at least sched_setattr(), perf_event_open(),
and clone3(). More importantly it will also help to ensure that users
implementing versioning-by-size end up with the same core semantics.
This point is especially crucial since we have at least one case where
versioning-by-size is used but with slighly different semantics:
sched_setattr(), perf_event_open(), and clone3() all do do similar
checks to copy_struct_from_user() while rt_sigprocmask(2) always
rejects differently-sized struct arguments.
With this pull request we also switch over sched_setattr(),
perf_event_open(), and clone3() to use the new helper"
* tag 'copy-struct-from-user-v5.4-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
usercopy: Add parentheses around assignment in test_copy_struct_from_user
perf_event_open: switch to copy_struct_from_user()
sched_setattr: switch to copy_struct_from_user()
clone3: switch to copy_struct_from_user()
lib: introduce copy_struct_from_user() helper
008847f66c ("workqueue: allow rescuer thread to do more work.") made
the rescuer worker requeue the pwq immediately if there may be more
work items which need rescuing instead of waiting for the next mayday
timer expiration. Unfortunately, it doesn't check whether the pwq is
already on the mayday list and unconditionally gets the ref and moves
it onto the list. This doesn't corrupt the list but creates an
additional reference to the pwq. It got queued twice but will only be
removed once.
This leak later can trigger pwq refcnt warning on workqueue
destruction and prevent freeing of the workqueue.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "Williams, Gerald S" <gerald.s.williams@intel.com>
Cc: NeilBrown <neilb@suse.de>
Cc: stable@vger.kernel.org # v3.19+
destroy_workqueue() warnings still, at a lower frequency, trigger
spuriously. The problem seems to be in-flight operations which
haven't reached put_pwq() yet.
* Make sanity check grab all the related locks so that it's
synchronized against operations which puts pwq at the end.
* Always print out the offending pwq.
Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: "Williams, Gerald S" <gerald.s.williams@intel.com>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXZZKNgAKCRCRxhvAZXjc
otfIAPsHUZn+Wfa/8uftNDJ6RLDXDsq6l8xiQTkz+k4YdnDj2AD/aIPjrM950jrS
W7+8R7CSSQOLmIif6R+S0A1fyFoVlQA=
=HVz0
-----END PGP SIGNATURE-----
Merge tag 'for-linus-20191003' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull clone3/pidfd fixes from Christian Brauner:
"This contains a couple of fixes:
- Fix pidfd selftest compilation (Shuah Kahn)
Due to a false linking instruction in the Makefile compilation for
the pidfd selftests would fail on some systems.
- Fix compilation for glibc on RISC-V systems (Seth Forshee)
In some scenarios linux/uapi/linux/sched.h is included where
__ASSEMBLY__ is defined causing a build failure because struct
clone_args was not guarded by an #ifndef __ASSEMBLY__.
- Add missing clone3() and struct clone_args kernel-doc (Christian Brauner)
clone3() and struct clone_args were missing kernel-docs. (The goal
is to use kernel-doc for any function or type where it's worth it.)
For struct clone_args this also contains a comment about the fact
that it's versioned by size"
* tag 'for-linus-20191003' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
sched: add kernel-doc for struct clone_args
fork: add kernel-doc for clone3
selftests: pidfd: Fix undefined reference to pthread_create()
sched: Add __ASSEMBLY__ guards around struct clone_args
This renames the very specific audit_log_link_denied() to
audit_log_path_denied() and adds the AUDIT_* type as an argument. This
allows for the creation of the new AUDIT_ANOM_CREAT that can be used to
report the fifo/regular file creation restrictions that were introduced
in commit 30aba6656f ("namei: allow restricted O_CREAT of FIFOs and
regular files").
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Pull timer fix from Ingo Molnar:
"Fix a broadcast-timer handling race that can result in spuriously and
indefinitely delayed hrtimers and even RCU stalls if the system is
otherwise quiet"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick: broadcast-hrtimer: Fix a race in bc_set_next
The following commit:
227a4aadc7 ("sched/membarrier: Fix p->mm->membarrier_state racy load")
got fat fingered by me when merging it with other patches. It meant to move
the RCU section out of the for loop but ended up doing it partially, leaving
a superfluous rcu_read_lock() inside, causing havok.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linux-tip-commits@vger.kernel.org
Fixes: 227a4aadc7 ("sched/membarrier: Fix p->mm->membarrier_state racy load")
Link: https://lkml.kernel.org/r/20191001085033.GP4519@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Switch perf_event_open() syscall from it's own copying
struct perf_event_attr from userspace to the new dedicated
copy_struct_from_user() helper.
The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-5-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Switch sched_setattr() syscall from it's own copying struct sched_attr
from userspace to the new dedicated copy_struct_from_user() helper.
The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls. Ideally we could also
unify sched_getattr(2)-style syscalls as well, but unfortunately the
correct semantics for such syscalls are much less clear (see [1] for
more detail). In future we could come up with a more sane idea for how
the syscall interface should look.
[1]: commit 1251201c0d ("sched/core: Fix uclamp ABI bug, clean up and
robustify sched_read_attr() ABI logic and code")
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-4-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Switch clone3() syscall from it's own copying struct clone_args from
userspace to the new dedicated copy_struct_from_user() helper.
The change is very straightforward, and helps unify the syscall
interface for struct-from-userspace syscalls. Additionally, explicitly
define CLONE_ARGS_SIZE_VER0 to match the other users of the
struct-extension pattern.
Signed-off-by: Aleksa Sarai <cyphar@cyphar.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christian Brauner <christian.brauner@ubuntu.com>
[christian.brauner@ubuntu.com: improve commit message]
Link: https://lore.kernel.org/r/20191001011055.19283-3-cyphar@cyphar.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
KUnit tests for initialized data behavior of proc_dointvec that is
explicitly checked in the code. Includes basic parsing tests including
int min/max overflow.
Signed-off-by: Iurii Zaikin <yzaikin@google.com>
Signed-off-by: Brendan Higgins <brendanhiggins@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
- Fixed a buffer overflow by checking nr_args correctly in probes
- Fixed a warning that is reported by clang
- Fixed a possible memory leak in error path of filter processing
- Fixed the selftest that checks for failures, but wasn't failing
- Minor clean up on call site output of a memory trace event
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXZEP5hQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qhrSAQDlws8rY/vJN4tKL1YaBTRyS5OW+1B+
LPLOxm9PBuzt0wEArVunv7iMgvRzp5spbmCqmD8Is2vSf+45KSrb10WU2wo=
=L37R
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"A few more tracing fixes:
- Fix a buffer overflow by checking nr_args correctly in probes
- Fix a warning that is reported by clang
- Fix a possible memory leak in error path of filter processing
- Fix the selftest that checks for failures, but wasn't failing
- Minor clean up on call site output of a memory trace event"
* tag 'trace-v5.4-3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
selftests/ftrace: Fix same probe error test
mm, tracing: Print symbol name for call_site in trace events
tracing: Have error path in predicate_parse() free its allocated memory
tracing: Fix clang -Wint-in-bool-context warnings in IF_ASSIGN macro
tracing/probe: Fix to check the difference of nr_args before adding probe
Pull networking fixes from David Miller:
1) Sanity check URB networking device parameters to avoid divide by
zero, from Oliver Neukum.
2) Disable global multicast filter in NCSI, otherwise LLDP and IPV6
don't work properly. Longer term this needs a better fix tho. From
Vijay Khemka.
3) Small fixes to selftests (use ping when ping6 is not present, etc.)
from David Ahern.
4) Bring back rt_uses_gateway member of struct rtable, it's semantics
were not well understood and trying to remove it broke things. From
David Ahern.
5) Move usbnet snaity checking, ignore endpoints with invalid
wMaxPacketSize. From Bjørn Mork.
6) Missing Kconfig deps for sja1105 driver, from Mao Wenan.
7) Various small fixes to the mlx5 DR steering code, from Alaa Hleihel,
Alex Vesker, and Yevgeny Kliteynik
8) Missing CAP_NET_RAW checks in various places, from Ori Nimron.
9) Fix crash when removing sch_cbs entry while offloading is enabled,
from Vinicius Costa Gomes.
10) Signedness bug fixes, generally in looking at the result given by
of_get_phy_mode() and friends. From Dan Crapenter.
11) Disable preemption around BPF_PROG_RUN() calls, from Eric Dumazet.
12) Don't create VRF ipv6 rules if ipv6 is disabled, from David Ahern.
13) Fix quantization code in tcp_bbr, from Kevin Yang.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (127 commits)
net: tap: clean up an indentation issue
nfp: abm: fix memory leak in nfp_abm_u32_knode_replace
tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state
sk_buff: drop all skb extensions on free and skb scrubbing
tcp_bbr: fix quantization code to not raise cwnd if not probing bandwidth
mlxsw: spectrum_flower: Fail in case user specifies multiple mirror actions
Documentation: Clarify trap's description
mlxsw: spectrum: Clear VLAN filters during port initialization
net: ena: clean up indentation issue
NFC: st95hf: clean up indentation issue
net: phy: micrel: add Asym Pause workaround for KSZ9021
net: socionext: ave: Avoid using netdev_err() before calling register_netdev()
ptp: correctly disable flags on old ioctls
lib: dimlib: fix help text typos
net: dsa: microchip: Always set regmap stride to 1
nfp: flower: fix memory leak in nfp_flower_spawn_vnic_reprs
nfp: flower: prevent memory leak in nfp_flower_spawn_phy_reprs
net/sched: Set default of CONFIG_NET_TC_SKB_EXT to N
vrf: Do not attempt to create IPv6 mcast rule if IPv6 is disabled
net: sched: sch_sfb: don't call qdisc_put() while holding tree lock
...
In predicate_parse, there is an error path that is not going to
out_free instead it returns directly which leads to a memory leak.
Link: http://lkml.kernel.org/r/20190920225800.3870-1-navid.emamdoost@gmail.com
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
After r372664 in clang, the IF_ASSIGN macro causes a couple hundred
warnings along the lines of:
kernel/trace/trace_output.c:1331:2: warning: converting the enum
constant to a boolean [-Wint-in-bool-context]
kernel/trace/trace.h:409:3: note: expanded from macro
'trace_assign_type'
IF_ASSIGN(var, ent, struct ftrace_graph_ret_entry,
^
kernel/trace/trace.h:371:14: note: expanded from macro 'IF_ASSIGN'
WARN_ON(id && (entry)->type != id); \
^
264 warnings generated.
This warning can catch issues with constructs like:
if (state == A || B)
where the developer really meant:
if (state == A || state == B)
This is currently the only occurrence of the warning in the kernel
tree across defconfig, allyesconfig, allmodconfig for arm32, arm64,
and x86_64. Add the implicit '!= 0' to the WARN_ON statement to fix
the warnings and find potential issues in the future.
Link: 28b38c277a
Link: https://github.com/ClangBuiltLinux/linux/issues/686
Link: http://lkml.kernel.org/r/20190926162258.466321-1-natechancellor@gmail.com
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Steven reported that a test triggered:
==================================================================
BUG: KASAN: slab-out-of-bounds in trace_kprobe_create+0xa9e/0xe40
Read of size 8 at addr ffff8880c4f25a48 by task ftracetest/4798
CPU: 2 PID: 4798 Comm: ftracetest Not tainted 5.3.0-rc6-test+ #30
Hardware name: Hewlett-Packard HP Compaq Pro 6300 SFF/339A, BIOS K01 v03.03 07/14/2016
Call Trace:
dump_stack+0x7c/0xc0
? trace_kprobe_create+0xa9e/0xe40
print_address_description+0x6c/0x332
? trace_kprobe_create+0xa9e/0xe40
? trace_kprobe_create+0xa9e/0xe40
__kasan_report.cold.6+0x1a/0x3b
? trace_kprobe_create+0xa9e/0xe40
kasan_report+0xe/0x12
trace_kprobe_create+0xa9e/0xe40
? print_kprobe_event+0x280/0x280
? match_held_lock+0x1b/0x240
? find_held_lock+0xac/0xd0
? fs_reclaim_release.part.112+0x5/0x20
? lock_downgrade+0x350/0x350
? kasan_unpoison_shadow+0x30/0x40
? __kasan_kmalloc.constprop.6+0xc1/0xd0
? trace_kprobe_create+0xe40/0xe40
? trace_kprobe_create+0xe40/0xe40
create_or_delete_trace_kprobe+0x2e/0x60
trace_run_command+0xc3/0xe0
? trace_panic_handler+0x20/0x20
? kasan_unpoison_shadow+0x30/0x40
trace_parse_run_command+0xdc/0x163
vfs_write+0xe1/0x240
ksys_write+0xba/0x150
? __ia32_sys_read+0x50/0x50
? tracer_hardirqs_on+0x61/0x180
? trace_hardirqs_off_caller+0x43/0x110
? mark_held_locks+0x29/0xa0
? do_syscall_64+0x14/0x260
do_syscall_64+0x68/0x260
Fix to check the difference of nr_args before adding probe
on existing probes. This also may set the error log index
bigger than the number of command parameters. In that case
it sets the error position is next to the last parameter.
Link: http://lkml.kernel.org/r/156966474783.3478.13217501608215769150.stgit@devnote2
Fixes: ca89bc071d ("tracing/kprobe: Add multi-probe per event support")
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pull scheduler fixes from Ingo Molnar:
- Apply a number of membarrier related fixes and cleanups, which fixes
a use-after-free race in the membarrier code
- Introduce proper RCU protection for tasks on the runqueue - to get
rid of the subtle task_rcu_dereference() interface that was easy to
get wrong
- Misc fixes, but also an EAS speedup
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Avoid redundant EAS calculation
sched/core: Remove double update_max_interval() call on CPU startup
sched/core: Fix preempt_schedule() interrupt return comment
sched/fair: Fix -Wunused-but-set-variable warnings
sched/core: Fix migration to invalid CPU in __set_cpus_allowed_ptr()
sched/membarrier: Return -ENOMEM to userspace on memory allocation failure
sched/membarrier: Skip IPIs when mm->mm_users == 1
selftests, sched/membarrier: Add multi-threaded test
sched/membarrier: Fix p->mm->membarrier_state racy load
sched/membarrier: Call sync_core only before usermode for same mm
sched/membarrier: Remove redundant check
sched/membarrier: Fix private expedited registration check
tasks, sched/core: RCUify the assignment of rq->curr
tasks, sched/core: With a grace period after finish_task_switch(), remove unnecessary code
tasks, sched/core: Ensure tasks are available for a grace period after leaving the runqueue
tasks: Add a count of task RCU users
sched/core: Convert vcpu_is_preempted() from macro to an inline function
sched/fair: Remove unused cfs_rq_clock_task() function
Pull kernel lockdown mode from James Morris:
"This is the latest iteration of the kernel lockdown patchset, from
Matthew Garrett, David Howells and others.
From the original description:
This patchset introduces an optional kernel lockdown feature,
intended to strengthen the boundary between UID 0 and the kernel.
When enabled, various pieces of kernel functionality are restricted.
Applications that rely on low-level access to either hardware or the
kernel may cease working as a result - therefore this should not be
enabled without appropriate evaluation beforehand.
The majority of mainstream distributions have been carrying variants
of this patchset for many years now, so there's value in providing a
doesn't meet every distribution requirement, but gets us much closer
to not requiring external patches.
There are two major changes since this was last proposed for mainline:
- Separating lockdown from EFI secure boot. Background discussion is
covered here: https://lwn.net/Articles/751061/
- Implementation as an LSM, with a default stackable lockdown LSM
module. This allows the lockdown feature to be policy-driven,
rather than encoding an implicit policy within the mechanism.
The new locked_down LSM hook is provided to allow LSMs to make a
policy decision around whether kernel functionality that would allow
tampering with or examining the runtime state of the kernel should be
permitted.
The included lockdown LSM provides an implementation with a simple
policy intended for general purpose use. This policy provides a coarse
level of granularity, controllable via the kernel command line:
lockdown={integrity|confidentiality}
Enable the kernel lockdown feature. If set to integrity, kernel features
that allow userland to modify the running kernel are disabled. If set to
confidentiality, kernel features that allow userland to extract
confidential information from the kernel are also disabled.
This may also be controlled via /sys/kernel/security/lockdown and
overriden by kernel configuration.
New or existing LSMs may implement finer-grained controls of the
lockdown features. Refer to the lockdown_reason documentation in
include/linux/security.h for details.
The lockdown feature has had signficant design feedback and review
across many subsystems. This code has been in linux-next for some
weeks, with a few fixes applied along the way.
Stephen Rothwell noted that commit 9d1f8be5cf ("bpf: Restrict bpf
when kernel lockdown is in confidentiality mode") is missing a
Signed-off-by from its author. Matthew responded that he is providing
this under category (c) of the DCO"
* 'next-lockdown' of git://git.kernel.org/pub/scm/linux/kernel/git/jmorris/linux-security: (31 commits)
kexec: Fix file verification on S390
security: constify some arrays in lockdown LSM
lockdown: Print current->comm in restriction messages
efi: Restrict efivar_ssdt_load when the kernel is locked down
tracefs: Restrict tracefs when the kernel is locked down
debugfs: Restrict debugfs when the kernel is locked down
kexec: Allow kexec_file() with appropriate IMA policy when locked down
lockdown: Lock down perf when in confidentiality mode
bpf: Restrict bpf when kernel lockdown is in confidentiality mode
lockdown: Lock down tracing and perf kprobes when in confidentiality mode
lockdown: Lock down /proc/kcore
x86/mmiotrace: Lock down the testmmiotrace module
lockdown: Lock down module params that specify hardware parameters (eg. ioport)
lockdown: Lock down TIOCSSERIAL
lockdown: Prohibit PCMCIA CIS storage when the kernel is locked down
acpi: Disable ACPI table override if the kernel is locked down
acpi: Ignore acpi_rsdp kernel param when the kernel has been locked down
ACPI: Limit access to custom_method when the kernel is locked down
x86/msr: Restrict MSR access when the kernel is locked down
x86: Lock down IO port access when the kernel is locked down
...
Pull integrity updates from Mimi Zohar:
"The major feature in this time is IMA support for measuring and
appraising appended file signatures. In addition are a couple of bug
fixes and code cleanup to use struct_size().
In addition to the PE/COFF and IMA xattr signatures, the kexec kernel
image may be signed with an appended signature, using the same
scripts/sign-file tool that is used to sign kernel modules.
Similarly, the initramfs may contain an appended signature.
This contained a lot of refactoring of the existing appended signature
verification code, so that IMA could retain the existing framework of
calculating the file hash once, storing it in the IMA measurement list
and extending the TPM, verifying the file's integrity based on a file
hash or signature (eg. xattrs), and adding an audit record containing
the file hash, all based on policy. (The IMA support for appended
signatures patch set was posted and reviewed 11 times.)
The support for appended signature paves the way for adding other
signature verification methods, such as fs-verity, based on a single
system-wide policy. The file hash used for verifying the signature and
the signature, itself, can be included in the IMA measurement list"
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
ima: ima_api: Use struct_size() in kzalloc()
ima: use struct_size() in kzalloc()
sefltest/ima: support appended signatures (modsig)
ima: Fix use after free in ima_read_modsig()
MODSIGN: make new include file self contained
ima: fix freeing ongoing ahash_request
ima: always return negative code for error
ima: Store the measurement again when appraising a modsig
ima: Define ima-modsig template
ima: Collect modsig
ima: Implement support for module-style appended signatures
ima: Factor xattr_verify() out of ima_appraise_measurement()
ima: Add modsig appraise_type option for module-style appended signatures
integrity: Select CONFIG_KEYS instead of depending on it
PKCS#7: Introduce pkcs7_get_digest()
PKCS#7: Refactor verify_pkcs7_signature()
MODSIGN: Export module signature definitions
ima: initialize the "template" field with the default template
* The usual accuracy improvements for nested virtualization
* The usual round of code cleanups from Sean
* Added back optimizations that were prematurely removed in 5.2
(the bare minimum needed to fix the regression was in 5.3-rc8,
here comes the rest)
* Support for UMWAIT/UMONITOR/TPAUSE
* Direct L2->L0 TLB flushing when L0 is Hyper-V and L1 is KVM
* Tell Windows guests if SMT is disabled on the host
* More accurate detection of vmexit cost
* Revert a pvqspinlock pessimization
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJdjfaKAAoJEL/70l94x66D8MAH/2thJnM47tYtMTFA4GBFugeH
mAx8OApWFBo8apOip+8ElFLPQ8FQdZCzr9ti8H4JkuzKxgsxCs1iqEg5pHEKxSTi
K9kLOZwoFtwgy3XmxC0PIZ9lT2Wx74ruh1HF+QG/YsjKH636UPv2VpmulsTNbm62
2ryzOb3TlGT/cjf+gv9l6IYIxZa2Ff19PF4i//H8u4YRBj358/jr99CK01iE0M9r
4NhEKiQZywzREWtKxymGOM6HEbwbWcIa+loYjj2htq8epep6f9Y1zQ0Jcn5+nPA0
cn1T2gGJAJ0OUahKLwNbz8pzrFDkW+eoQgqCBJZ4RT9Uf8WCESfl14p+/vRkAMg=
=tk5S
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Paolo Bonzini:
"x86 KVM changes:
- The usual accuracy improvements for nested virtualization
- The usual round of code cleanups from Sean
- Added back optimizations that were prematurely removed in 5.2 (the
bare minimum needed to fix the regression was in 5.3-rc8, here
comes the rest)
- Support for UMWAIT/UMONITOR/TPAUSE
- Direct L2->L0 TLB flushing when L0 is Hyper-V and L1 is KVM
- Tell Windows guests if SMT is disabled on the host
- More accurate detection of vmexit cost
- Revert a pvqspinlock pessimization"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (56 commits)
KVM: nVMX: cleanup and fix host 64-bit mode checks
KVM: vmx: fix build warnings in hv_enable_direct_tlbflush() on i386
KVM: x86: Don't check kvm_rebooting in __kvm_handle_fault_on_reboot()
KVM: x86: Drop ____kvm_handle_fault_on_reboot()
KVM: VMX: Add error handling to VMREAD helper
KVM: VMX: Optimize VMX instruction error and fault handling
KVM: x86: Check kvm_rebooting in kvm_spurious_fault()
KVM: selftests: fix ucall on x86
Revert "locking/pvqspinlock: Don't wait if vCPU is preempted"
kvm: nvmx: limit atomic switch MSRs
kvm: svm: Intercept RDPRU
kvm: x86: Add "significant index" flag to a few CPUID leaves
KVM: x86/mmu: Skip invalid pages during zapping iff root_count is zero
KVM: x86/mmu: Explicitly track only a single invalid mmu generation
KVM: x86/mmu: Revert "KVM: x86/mmu: Remove is_obsolete() call"
KVM: x86/mmu: Revert "Revert "KVM: MMU: reclaim the zapped-obsolete page first""
KVM: x86/mmu: Revert "Revert "KVM: MMU: collapse TLB flushes when zap all pages""
KVM: x86/mmu: Revert "Revert "KVM: MMU: zap pages in batch""
KVM: x86/mmu: Revert "Revert "KVM: MMU: add tracepoint for kvm_mmu_invalidate_all_pages""
KVM: x86/mmu: Revert "Revert "KVM: MMU: show mmu_valid_gen in shadow page related tracepoints""
...
When a cpu requests broadcasting, before starting the tick broadcast
hrtimer, bc_set_next() checks if the timer callback (bc_handler) is active
using hrtimer_try_to_cancel(). But hrtimer_try_to_cancel() does not provide
the required synchronization when the callback is active on other core.
The callback could have already executed tick_handle_oneshot_broadcast()
and could have also returned. But still there is a small time window where
the hrtimer_try_to_cancel() returns -1. In that case bc_set_next() returns
without doing anything, but the next_event of the tick broadcast clock
device is already set to a timeout value.
In the race condition diagram below, CPU #1 is running the timer callback
and CPU #2 is entering idle state and so calls bc_set_next().
In the worst case, the next_event will contain an expiry time, but the
hrtimer will not be started which happens when the racing callback returns
HRTIMER_NORESTART. The hrtimer might never recover if all further requests
from the CPUs to subscribe to tick broadcast have timeout greater than the
next_event of tick broadcast clock device. This leads to cascading of
failures and finally noticed as rcu stall warnings
Here is a depiction of the race condition
CPU #1 (Running timer callback) CPU #2 (Enter idle
and subscribe to
tick broadcast)
--------------------- ---------------------
__run_hrtimer() tick_broadcast_enter()
bc_handler() __tick_broadcast_oneshot_control()
tick_handle_oneshot_broadcast()
raw_spin_lock(&tick_broadcast_lock);
dev->next_event = KTIME_MAX; //wait for tick_broadcast_lock
//next_event for tick broadcast clock
set to KTIME_MAX since no other cores
subscribed to tick broadcasting
raw_spin_unlock(&tick_broadcast_lock);
if (dev->next_event == KTIME_MAX)
return HRTIMER_NORESTART
// callback function exits without
restarting the hrtimer //tick_broadcast_lock acquired
raw_spin_lock(&tick_broadcast_lock);
tick_broadcast_set_event()
clockevents_program_event()
dev->next_event = expires;
bc_set_next()
hrtimer_try_to_cancel()
//returns -1 since the timer
callback is active. Exits without
restarting the timer
cpu_base->running = NULL;
The comment that hrtimer cannot be armed from within the callback is
wrong. It is fine to start the hrtimer from within the callback. Also it is
safe to start the hrtimer from the enter/exit idle code while the broadcast
handler is active. The enter/exit idle code and the broadcast handler are
synchronized using tick_broadcast_lock. So there is no need for the
existing try to cancel logic. All this can be removed which will eliminate
the race condition as well.
Fixes: 5d1638acb9 ("tick: Introduce hrtimer based broadcast")
Originally-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Balasubramani Vivekanandan <balasubramani_vivekanandan@mentor.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190926135101.12102-2-balasubramani_vivekanandan@mentor.com
Pull timer fix from Ingo Molnar:
"Fix a timer expiry bug that would cause spurious delay of timers"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timer: Read jiffies once when forwarding base clk
Pull more perf updates from Ingo Molnar:
"The only kernel change is comment typo fixes.
The rest is mostly tooling fixes, but also new vendor event additions
and updates, a bigger libperf/libtraceevent library and a header files
reorganization that came in a bit late"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (108 commits)
perf unwind: Fix libunwind build failure on i386 systems
perf parser: Remove needless include directives
perf build: Add detection of java-11-openjdk-devel package
perf jvmti: Include JVMTI support for s390
perf vendor events: Remove P8 HW events which are not supported
perf evlist: Fix access of freed id arrays
perf stat: Fix free memory access / memory leaks in metrics
perf tools: Replace needless mmap.h with what is needed, event.h
perf evsel: Move config terms to a separate header
perf evlist: Remove unused perf_evlist__fprintf() method
perf evsel: Introduce evsel_fprintf.h
perf evsel: Remove need for symbol_conf in evsel_fprintf.c
perf copyfile: Move copyfile routines to separate files
libperf: Add perf_evlist__poll() function
libperf: Add perf_evlist__add_pollfd() function
libperf: Add perf_evlist__alloc_pollfd() function
libperf: Add libperf_init() call to the tests
libperf: Merge libperf_set_print() into libperf_init()
libperf: Add libperf dependency for tests targets
libperf: Use sys/types.h to get ssize_t, not unistd.h
...
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXYvAlBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlK6APsECr49j3ew/tRCnzkq0Y09w0TLYeHL
ax6aAVO1fHX0TgEAhCBwkWh8ZcoxGbu1CDOkQjJAqfTFFSu38Klv1P+3PQg=
=oSuX
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Srikar Dronamraju fixed a bug in the newmulti probe code"
* tag 'trace-v5.4-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing/probe: Fix same probe event argument matching
In preparation for cleaning up "cut here", move the "cut here" logic up
out of __warn() and into callers that pass non-NULL args. For anyone
looking closely, there are two callers that pass NULL args: one already
explicitly prints "cut here". The remaining case is covered by how a WARN
is built, which will be cleaned up in the next patch.
Link: http://lkml.kernel.org/r/20190819234111.9019-5-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Drew Davenport <ddavenport@chromium.org>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "Clean up WARN() "cut here" handling", v2.
Christophe Leroy noticed that the fix for missing "cut here" in the WARN()
case was adding explicit printk() calls instead of teaching the exception
handler to add it. This refactors the bug/warn infrastructure to pass
this information as a new BUGFLAG.
Longer details repeated from the last patch in the series:
bug: move WARN_ON() "cut here" into exception handler
The original cleanup of "cut here" missed the WARN_ON() case (that does
not have a printk message), which was fixed recently by adding an explicit
printk of "cut here". This had the downside of adding a printk() to every
WARN_ON() caller, which reduces the utility of using an instruction
exception to streamline the resulting code. By making this a new BUGFLAG,
all of these can be removed and "cut here" can be handled by the exception
handler.
This was very pronounced on PowerPC, but the effect can be seen on x86 as
well. The resulting text size of a defconfig build shows some small
savings from this patch:
text data bss dec hex filename
19691167 5134320 1646664 26472151 193eed7 vmlinux.before
19676362 5134260 1663048 26473670 193f4c6 vmlinux.after
This change also opens the door for creating something like BUG_MSG(),
where a custom printk() before issuing BUG(), without confusing the "cut
here" line.
This patch (of 7):
There's no reason to have specialized helpers for passing the warn taint
down to __warn(). Consolidate and refactor helper macros, removing
__WARN_printf() and warn_slowpath_fmt_taint().
Link: http://lkml.kernel.org/r/20190819234111.9019-2-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Christophe Leroy <christophe.leroy@c-s.fr>
Cc: Drew Davenport <ddavenport@chromium.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Cc: Feng Tang <feng.tang@intel.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: YueHaibing <yuehaibing@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Right now kgdb/kdb hooks up to debug panics by registering for the panic
notifier. This works OK except that it means that kgdb/kdb gets called
_after_ the CPUs in the system are taken offline. That means that if
anything important was happening on those CPUs (like something that might
have contributed to the panic) you can't debug them.
Specifically I ran into a case where I got a panic because a task was
"blocked for more than 120 seconds" which was detected on CPU 2. I nicely
got shown stack traces in the kernel log for all CPUs including CPU 0,
which was running 'PID: 111 Comm: kworker/0:1H' and was in the middle of
__mmc_switch().
I then ended up at the kdb prompt where switched over to kgdb to try to
look at local variables of the process on CPU 0. I found that I couldn't.
Digging more, I found that I had no info on any tasks running on CPUs
other than CPU 2 and that asking kdb for help showed me "Error: no saved
data for this cpu". This was because all the CPUs were offline.
Let's move the entry of kdb/kgdb to a direct call from panic() and stop
using the generic notifier. Putting a direct call in allows us to order
things more properly and it also doesn't seem like we're breaking any
abstractions by calling into the debugger from the panic function.
Daniel said:
: This patch changes the way kdump and kgdb interact with each other.
: However it would seem rather odd to have both tools simultaneously armed
: and, even if they were, the user still has the option to use panic_timeout
: to force a kdump to happen. Thus I think the change of order is
: acceptable.
Link: http://lkml.kernel.org/r/20190703170354.217312-1-dianders@chromium.org
Signed-off-by: Douglas Anderson <dianders@chromium.org>
Reviewed-by: Daniel Thompson <daniel.thompson@linaro.org>
Cc: Jason Wessel <jason.wessel@windriver.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Feng Tang <feng.tang@intel.com>
Cc: YueHaibing <yuehaibing@huawei.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky.work@gmail.com>
Cc: "Steven Rostedt (VMware)" <rostedt@goodmis.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
syzbot found that a thread can stall for minutes inside kexec_load() after
that thread was killed by SIGKILL [1]. It turned out that the reproducer
was trying to allocate 2408MB of memory using kimage_alloc_page() from
kimage_load_normal_segment(). Let's check for SIGKILL before doing memory
allocation.
[1] https://syzkaller.appspot.com/bug?id=a0e3436829698d5824231251fad9d8e998f94f5e
Link: http://lkml.kernel.org/r/993c9185-d324-2640-d061-bed2dd18b1f7@I-love.SAKURA.ne.jp
Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Reported-by: syzbot <syzbot+8ab2d0f39fb79fe6ca40@syzkaller.appspotmail.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When a user process exits, the kernel cleans up the mm_struct of the user
process and during cleanup, check_mm() checks the page tables of the user
process for corruption (E.g: unexpected page flags set/cleared). For
corrupted page tables, the error message printed by check_mm() isn't very
clear as it prints the loop index instead of page table type (E.g:
Resident file mapping pages vs Resident shared memory pages). The loop
index in check_mm() is used to index rss_stat[] which represents
individual memory type stats. Hence, instead of printing index, print
memory type, thereby improving error message.
Without patch:
--------------
[ 204.836425] mm/pgtable-generic.c:29: bad p4d 0000000089eb4e92(800000025f941467)
[ 204.836544] BUG: Bad rss-counter state mm:00000000f75895ea idx:0 val:2
[ 204.836615] BUG: Bad rss-counter state mm:00000000f75895ea idx:1 val:5
[ 204.836685] BUG: non-zero pgtables_bytes on freeing mm: 20480
With patch:
-----------
[ 69.815453] mm/pgtable-generic.c:29: bad p4d 0000000084653642(800000025ca37467)
[ 69.815872] BUG: Bad rss-counter state mm:00000000014a6c03 type:MM_FILEPAGES val:2
[ 69.815962] BUG: Bad rss-counter state mm:00000000014a6c03 type:MM_ANONPAGES val:5
[ 69.816050] BUG: non-zero pgtables_bytes on freeing mm: 20480
Also, change print function (from printk(KERN_ALERT, ..) to pr_alert()) so
that it matches the other print statement.
Link: http://lkml.kernel.org/r/da75b5153f617f4c5739c08ee6ebeb3d19db0fbc.1565123758.git.sai.praneeth.prakhya@intel.com
Signed-off-by: Sai Praneeth Prakhya <sai.praneeth.prakhya@intel.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Suggested-by: Dave Hansen <dave.hansen@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Dave Hansen <dave.hansen@intel.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When building with W=1, gcc properly complains that there's no prototypes:
CC kernel/elfcore.o
kernel/elfcore.c:7:17: warning: no previous prototype for 'elf_core_extra_phdrs' [-Wmissing-prototypes]
7 | Elf_Half __weak elf_core_extra_phdrs(void)
| ^~~~~~~~~~~~~~~~~~~~
kernel/elfcore.c:12:12: warning: no previous prototype for 'elf_core_write_extra_phdrs' [-Wmissing-prototypes]
12 | int __weak elf_core_write_extra_phdrs(struct coredump_params *cprm, loff_t offset)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
kernel/elfcore.c:17:12: warning: no previous prototype for 'elf_core_write_extra_data' [-Wmissing-prototypes]
17 | int __weak elf_core_write_extra_data(struct coredump_params *cprm)
| ^~~~~~~~~~~~~~~~~~~~~~~~~
kernel/elfcore.c:22:15: warning: no previous prototype for 'elf_core_extra_data_size' [-Wmissing-prototypes]
22 | size_t __weak elf_core_extra_data_size(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~
Provide the include file so gcc is happy, and we don't have potential code drift
Link: http://lkml.kernel.org/r/29875.1565224705@turing-police
Signed-off-by: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When kzalloc() failed, NULL was returned to the caller, which
tested the pointer with IS_ERR(), which didn't match, so the
pointer was used later, resulting in a NULL dereference.
Return ERR_PTR(-ENOMEM) instead of NULL.
Reported-by: syzbot+491c1b7565ba9069ecae@syzkaller.appspotmail.com
Fixes: 0402acd683 ("xsk: remove AF_XDP socket from map when the socket is released")
Signed-off-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The EAS wake-up path computes the system energy for several CPU
candidates: the CPU with maximum spare capacity in each performance
domain, and the prev_cpu. However, if prev_cpu also happens to be the
CPU with maximum spare capacity in its performance domain, the energy
calculation is still done twice, unnecessarily.
Add a condition to filter out this corner case before doing the energy
calculation.
Reported-by: Pavan Kondeti <pkondeti@codeaurora.org>
Signed-off-by: Quentin Perret <qperret@qperret.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: morten.rasmussen@arm.com
Cc: qais.yousef@arm.com
Cc: rjw@rjwysocki.net
Cc: tkjos@google.com
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Fixes: eb92692b25 ("sched/fair: Speed-up energy-aware wake-ups")
Link: https://lkml.kernel.org/r/20190920094115.GA11503@qperret.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
update_max_interval() is called in both CPUHP_AP_SCHED_STARTING's startup
and teardown callbacks, but it turns out it's also called at the end of
the startup callback of CPUHP_AP_ACTIVE (which is further down the
startup sequence).
There's no point in repeating this interval update in the startup sequence
since the CPU will remain online until it goes down the teardown path.
Remove the redundant call in sched_cpu_activate() (CPUHP_AP_ACTIVE).
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: vincent.guittot@linaro.org
Link: https://lkml.kernel.org/r/20190923093017.11755-1-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit:
de53fd7aed ("sched/fair: Fix low cpu usage with high throttling by removing expiration of cpu-local slices")
introduced a few compilation warnings:
kernel/sched/fair.c: In function '__refill_cfs_bandwidth_runtime':
kernel/sched/fair.c:4365:6: warning: variable 'now' set but not used [-Wunused-but-set-variable]
kernel/sched/fair.c: In function 'start_cfs_bandwidth':
kernel/sched/fair.c:4992:6: warning: variable 'overrun' set but not used [-Wunused-but-set-variable]
Also, __refill_cfs_bandwidth_runtime() does no longer update the
expiration time, so fix the comments accordingly.
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ben Segall <bsegall@google.com>
Reviewed-by: Dave Chiluk <chiluk+linux@indeed.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: pauld@redhat.com
Fixes: de53fd7aed ("sched/fair: Fix low cpu usage with high throttling by removing expiration of cpu-local slices")
Link: https://lkml.kernel.org/r/1566326455-8038-1-git-send-email-cai@lca.pw
Signed-off-by: Ingo Molnar <mingo@kernel.org>
An oops can be triggered in the scheduler when running qemu on arm64:
Unable to handle kernel paging request at virtual address ffff000008effe40
Internal error: Oops: 96000007 [#1] SMP
Process migration/0 (pid: 12, stack limit = 0x00000000084e3736)
pstate: 20000085 (nzCv daIf -PAN -UAO)
pc : __ll_sc___cmpxchg_case_acq_4+0x4/0x20
lr : move_queued_task.isra.21+0x124/0x298
...
Call trace:
__ll_sc___cmpxchg_case_acq_4+0x4/0x20
__migrate_task+0xc8/0xe0
migration_cpu_stop+0x170/0x180
cpu_stopper_thread+0xec/0x178
smpboot_thread_fn+0x1ac/0x1e8
kthread+0x134/0x138
ret_from_fork+0x10/0x18
__set_cpus_allowed_ptr() will choose an active dest_cpu in affinity mask to
migrage the process if process is not currently running on any one of the
CPUs specified in affinity mask. __set_cpus_allowed_ptr() will choose an
invalid dest_cpu (dest_cpu >= nr_cpu_ids, 1024 in my virtual machine) if
CPUS in an affinity mask are deactived by cpu_down after cpumask_intersects
check. cpumask_test_cpu() of dest_cpu afterwards is overflown and may pass if
corresponding bit is coincidentally set. As a consequence, kernel will
access an invalid rq address associate with the invalid CPU in
migration_cpu_stop->__migrate_task->move_queued_task and the Oops occurs.
The reproduce the crash:
1) A process repeatedly binds itself to cpu0 and cpu1 in turn by calling
sched_setaffinity.
2) A shell script repeatedly does "echo 0 > /sys/devices/system/cpu/cpu1/online"
and "echo 1 > /sys/devices/system/cpu/cpu1/online" in turn.
3) Oops appears if the invalid CPU is set in memory after tested cpumask.
Signed-off-by: KeMeng Shi <shikemeng@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1568616808-16808-1-git-send-email-shikemeng@huawei.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove the IPI fallback code from membarrier to deal with very
infrequent cpumask memory allocation failure. Use GFP_KERNEL rather
than GFP_NOWAIT, and relax the blocking guarantees for the expedited
membarrier system call commands, allowing it to block if waiting for
memory to be made available.
In addition, now -ENOMEM can be returned to user-space if the cpumask
memory allocation fails.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190919173705.2181-8-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If there is only a single mm_user for the mm, the private expedited
membarrier command can skip the IPIs, because only a single thread
is using the mm.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190919173705.2181-7-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The membarrier_state field is located within the mm_struct, which
is not guaranteed to exist when used from runqueue-lock-free iteration
on runqueues by the membarrier system call.
Copy the membarrier_state from the mm_struct into the scheduler runqueue
when the scheduler switches between mm.
When registering membarrier for mm, after setting the registration bit
in the mm membarrier state, issue a synchronize_rcu() to ensure the
scheduler observes the change. In order to take care of the case
where a runqueue keeps executing the target mm without swapping to
other mm, iterate over each runqueue and issue an IPI to copy the
membarrier_state from the mm_struct into each runqueue which have the
same mm which state has just been modified.
Move the mm membarrier_state field closer to pgd in mm_struct to use
a cache line already touched by the scheduler switch_mm.
The membarrier_execve() (now membarrier_exec_mmap) hook now needs to
clear the runqueue's membarrier state in addition to clear the mm
membarrier state, so move its implementation into the scheduler
membarrier code so it can access the runqueue structure.
Add memory barrier in membarrier_exec_mmap() prior to clearing
the membarrier state, ensuring memory accesses executed prior to exec
are not reordered with the stores clearing the membarrier state.
As suggested by Linus, move all membarrier.c RCU read-side locks outside
of the for each cpu loops.
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190919173705.2181-5-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Checking that the number of threads is 1 is redundant with checking
mm_users == 1.
No change in functionality intended.
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190919173705.2181-3-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fix a logic flaw in the way membarrier_register_private_expedited()
handles ready state checks for private expedited sync core and private
expedited registrations.
If a private expedited membarrier registration is first performed, and
then a private expedited sync_core registration is performed, the ready
state check will skip the second registration when it really should not.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190919173705.2181-2-mathieu.desnoyers@efficios.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The current task on the runqueue is currently read with rcu_dereference().
To obtain ordinary RCU semantics for an rcu_dereference() of rq->curr it needs
to be paired with rcu_assign_pointer() of rq->curr. Which provides the
memory barrier necessary to order assignments to the task_struct
and the assignment to rq->curr.
Unfortunately the assignment of rq->curr in __schedule is a hot path,
and it has already been show that additional barriers in that code
will reduce the performance of the scheduler. So I will attempt to
describe below why you can effectively have ordinary RCU semantics
without any additional barriers.
The assignment of rq->curr in init_idle is a slow path called once
per cpu and that can use rcu_assign_pointer() without any concerns.
As I write this there are effectively two users of rcu_dereference() on
rq->curr. There is the membarrier code in kernel/sched/membarrier.c
that only looks at "->mm" after the rcu_dereference(). Then there is
task_numa_compare() in kernel/sched/fair.c. My best reading of the
code shows that task_numa_compare only access: "->flags",
"->cpus_ptr", "->numa_group", "->numa_faults[]",
"->total_numa_faults", and "->se.cfs_rq".
The code in __schedule() essentially does:
rq_lock(...);
smp_mb__after_spinlock();
next = pick_next_task(...);
rq->curr = next;
context_switch(prev, next);
At the start of the function the rq_lock/smp_mb__after_spinlock
pair provides a full memory barrier. Further there is a full memory barrier
in context_switch().
This means that any task that has already run and modified itself (the
common case) has already seen two memory barriers before __schedule()
runs and begins executing. A task that modifies itself then sees a
third full memory barrier pair with the rq_lock();
For a brand new task that is enqueued with wake_up_new_task() there
are the memory barriers present from the taking and release the
pi_lock and the rq_lock as the processes is enqueued as well as the
full memory barrier at the start of __schedule() assuming __schedule()
happens on the same cpu.
This means that by the time we reach the assignment of rq->curr
except for values on the task struct modified in pick_next_task
the code has the same guarantees as if it used rcu_assign_pointer().
Reading through all of the implementations of pick_next_task it
appears pick_next_task is limited to modifying the task_struct fields
"->se", "->rt", "->dl". These fields are the sched_entity structures
of the varies schedulers.
Further "->se.cfs_rq" is only changed in cgroup attach/move operations
initialized by userspace.
Unless I have missed something this means that in practice that the
users of "rcu_dereference(rq->curr)" get normal RCU semantics of
rcu_dereference() for the fields the care about, despite the
assignment of rq->curr in __schedule() ot using rcu_assign_pointer.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/r/20190903200603.GW2349@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Remove work arounds that were written before there was a grace period
after tasks left the runqueue in finish_task_switch().
In particular now that there tasks exiting the runqueue exprience
a RCU grace period none of the work performed by task_rcu_dereference()
excpet the rcu_dereference() is necessary so replace task_rcu_dereference()
with rcu_dereference().
Remove the code in rcuwait_wait_event() that checks to ensure the current
task has not exited. It is no longer necessary as it is guaranteed
that any running task will experience a RCU grace period after it
leaves the run queueue.
Remove the comment in rcuwait_wake_up() as it is no longer relevant.
Ref: 8f95c90ceb ("sched/wait, RCU: Introduce rcuwait machinery")
Ref: 150593bf86 ("sched/api: Introduce task_rcu_dereference() and try_get_task_struct()")
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87lfurdpk9.fsf_-_@x220.int.ebiederm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In the ordinary case today the RCU grace period for a task_struct is
triggered when another process wait's for it's zombine and causes the
kernel to call release_task(). As the waiting task has to receive a
signal and then act upon it before this happens, typically this will
occur after the original task as been removed from the runqueue.
Unfortunaty in some cases such as self reaping tasks it can be shown
that release_task() will be called starting the grace period for
task_struct long before the task leaves the runqueue.
Therefore use put_task_struct_rcu_user() in finish_task_switch() to
guarantee that the there is a RCU lifetime after the task
leaves the runqueue.
Besides the change in the start of the RCU grace period for the
task_struct this change may cause perf_event_delayed_put and
trace_sched_process_free. The function perf_event_delayed_put boils
down to just a WARN_ON for cases that I assume never show happen. So
I don't see any problem with delaying it.
The function trace_sched_process_free is a trace point and thus
visible to user space. Occassionally userspace has the strangest
dependencies so this has a miniscule chance of causing a regression.
This change only changes the timing of when the tracepoint is called.
The change in timing arguably gives userspace a more accurate picture
of what is going on. So I don't expect there to be a regression.
In the case where a task self reaps we are pretty much guaranteed that
the RCU grace period is delayed. So we should get quite a bit of
coverage in of this worst case for the change in a normal threaded
workload. So I expect any issues to turn up quickly or not at all.
I have lightly tested this change and everything appears to work
fine.
Inspired-by: Linus Torvalds <torvalds@linux-foundation.org>
Inspired-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87r24jdpl5.fsf_-_@x220.int.ebiederm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add a count of the number of RCU users (currently 1) of the task
struct so that we can later add the scheduler case and get rid of the
very subtle task_rcu_dereference(), and just use rcu_dereference().
As suggested by Oleg have the count overlap rcu_head so that no
additional space in task_struct is required.
Inspired-by: Linus Torvalds <torvalds@linux-foundation.org>
Inspired-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Chris Metcalf <cmetcalf@ezchip.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Kirill Tkhai <tkhai@yandex.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Paul E. McKenney <paulmck@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Russell King - ARM Linux admin <linux@armlinux.org.uk>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/87woebdplt.fsf_-_@x220.int.ebiederm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Commit fe60b0ce8e ("tracing/probe: Reject exactly same probe event")
tries to reject a event which matches an already existing probe.
However it currently continues to match arguments and rejects adding a
probe even when the arguments don't match. Fix this by only rejecting a
probe if and only if all the arguments match.
Link: http://lkml.kernel.org/r/20190924114906.14038-1-srikar@linux.vnet.ibm.com
Fixes: fe60b0ce8e ("tracing/probe: Reject exactly same probe event")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This patch reverts commit 75437bb304 (locking/pvqspinlock: Don't
wait if vCPU is preempted). A large performance regression was caused
by this commit. on over-subscription scenarios.
The test was run on a Xeon Skylake box, 2 sockets, 40 cores, 80 threads,
with three VMs of 80 vCPUs each. The score of ebizzy -M is reduced from
13000-14000 records/s to 1700-1800 records/s:
Host Guest score
vanilla w/o kvm optimizations upstream 1700-1800 records/s
vanilla w/o kvm optimizations revert 13000-14000 records/s
vanilla w/ kvm optimizations upstream 4500-5000 records/s
vanilla w/ kvm optimizations revert 14000-15500 records/s
Exit from aggressive wait-early mechanism can result in premature yield
and extra scheduling latency.
Actually, only 6% of wait_early events are caused by vcpu_is_preempted()
being true. However, when one vCPU voluntarily releases its vCPU, all
the subsequently waiters in the queue will do the same and the cascading
effect leads to bad performance.
kvm optimizations:
[1] commit d73eb57b80 (KVM: Boost vCPUs that are delivering interrupts)
[2] commit 266e85a5ec (KVM: X86: Boost queue head vCPU to mitigate lock waiter preemption)
Tested-by: loobinliu@tencent.com
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Waiman Long <longman@redhat.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: loobinliu@tencent.com
Cc: stable@vger.kernel.org
Fixes: 75437bb304 (locking/pvqspinlock: Don't wait if vCPU is preempted)
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Merge updates from Andrew Morton:
- a few hot fixes
- ocfs2 updates
- almost all of -mm (slab-generic, slab, slub, kmemleak, kasan,
cleanups, debug, pagecache, memcg, gup, pagemap, memory-hotplug,
sparsemem, vmalloc, initialization, z3fold, compaction, mempolicy,
oom-kill, hugetlb, migration, thp, mmap, madvise, shmem, zswap,
zsmalloc)
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (132 commits)
mm/zsmalloc.c: fix a -Wunused-function warning
zswap: do not map same object twice
zswap: use movable memory if zpool support allocate movable memory
zpool: add malloc_support_movable to zpool_driver
shmem: fix obsolete comment in shmem_getpage_gfp()
mm/madvise: reduce code duplication in error handling paths
mm: mmap: increase sockets maximum memory size pgoff for 32bits
mm/mmap.c: refine find_vma_prev() with rb_last()
riscv: make mmap allocation top-down by default
mips: use generic mmap top-down layout and brk randomization
mips: replace arch specific way to determine 32bit task with generic version
mips: adjust brk randomization offset to fit generic version
mips: use STACK_TOP when computing mmap base address
mips: properly account for stack randomization and stack guard gap
arm: use generic mmap top-down layout and brk randomization
arm: use STACK_TOP when computing mmap base address
arm: properly account for stack randomization and stack guard gap
arm64, mm: make randomization selected by generic topdown mmap layout
arm64, mm: move generic mmap layout functions to mm
arm64: consider stack randomization for mmap base only when necessary
...
arm64 handles top-down mmap layout in a way that can be easily reused by
other architectures, so make it available in mm. It then introduces a new
config ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT that can be set by other
architectures to benefit from those functions. Note that this new config
depends on MMU being enabled, if selected without MMU support, a warning
will be thrown.
Link: http://lkml.kernel.org/r/20190730055113.23635-5-alex@ghiti.fr
Signed-off-by: Alexandre Ghiti <alex@ghiti.fr>
Suggested-by: Christoph Hellwig <hch@infradead.org>
Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Albert Ou <aou@eecs.berkeley.edu>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: James Hogan <jhogan@kernel.org>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Will Deacon <will.deacon@arm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
After all uprobes are removed from the huge page (with PTE pgtable), it is
possible to collapse the pmd and benefit from THP again. This patch does
the collapse by calling collapse_pte_mapped_thp().
Link: http://lkml.kernel.org/r/20190815164525.1848545-7-songliubraving@fb.com
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: kbuild test robot <lkp@intel.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the newly added FOLL_SPLIT_PMD in uprobe. This preserves the huge
page when the uprobe is enabled. When the uprobe is disabled, newer
instances of the same application could still benefit from huge page.
For the next step, we will enable khugepaged to regroup the pmd, so that
existing instances of the application could also benefit from huge page
after the uprobe is disabled.
Link: http://lkml.kernel.org/r/20190815164525.1848545-5-songliubraving@fb.com
Signed-off-by: Song Liu <songliubraving@fb.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, uprobe swaps the target page with a anonymous page in both
install_breakpoint() and remove_breakpoint(). When all uprobes on a page
are removed, the given mm is still using an anonymous page (not the
original page).
This patch allows uprobe to use original page when possible (all uprobes
on the page are already removed, and the original page is in page cache
and uptodate).
As suggested by Oleg, we unmap the old_page and let the original page
fault in.
Link: http://lkml.kernel.org/r/20190815164525.1848545-3-songliubraving@fb.com
Signed-off-by: Song Liu <songliubraving@fb.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm/memory_hotplug: online_pages() cleanups", v2.
Some cleanups (+ one fix for a special case) in the context of
online_pages().
This patch (of 5):
This makes it clearer that we will never call func() with duplicate PFNs
in case we have multiple sub-page memory resources. All unaligned parts
of PFNs are completely discarded.
Link: http://lkml.kernel.org/r/20190814154109.3448-2-david@redhat.com
Signed-off-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Wei Yang <richardw.yang@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Nadav Amit <namit@vmware.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Arun KS <arunks@codeaurora.org>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Patch series "mm: remove quicklist page table caches".
A while ago Nicholas proposed to remove quicklist page table caches [1].
I've rebased his patch on the curren upstream and switched ia64 and sh to
use generic versions of PTE allocation.
[1] https://lore.kernel.org/linux-mm/20190711030339.20892-1-npiggin@gmail.com
This patch (of 3):
Remove page table allocator "quicklists". These have been around for a
long time, but have not got much traction in the last decade and are only
used on ia64 and sh architectures.
The numbers in the initial commit look interesting but probably don't
apply anymore. If anybody wants to resurrect this it's in the git
history, but it's unhelpful to have this code and divergent allocator
behaviour for minor archs.
Also it might be better to instead make more general improvements to page
allocator if this is still so slow.
Link: http://lkml.kernel.org/r/1565250728-21721-2-git-send-email-rppt@linux.ibm.com
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Pull more mount API conversions from Al Viro:
"Assorted conversions of options parsing to new API.
gfs2 is probably the most serious one here; the rest is trivial stuff.
Other things in what used to be #work.mount are going to wait for the
next cycle (and preferably go via git trees of the filesystems
involved)"
* 'work.mount3' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
gfs2: Convert gfs2 to fs_context
vfs: Convert spufs to use the new mount API
vfs: Convert hypfs to use the new mount API
hypfs: Fix error number left in struct pointer member
vfs: Convert functionfs to use the new mount API
vfs: Convert bpf to use the new mount API
KVM needs to know if SMT is theoretically possible, this means it is
supported and not forcefully disabled ('nosmt=force'). Create and
export cpu_smt_possible() answering this question.
Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull livepatching fix from Jiri Kosina:
"Error handling fix in livepatching module notifier, from Miroslav
Benes"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
livepatch: Nullify obj->mod in klp_module_coming()'s error path
Summary of modules changes for the 5.4 merge window:
- Introduce exported symbol namespaces.
This new feature allows subsystem maintainers to partition and
categorize their exported symbols into explicit namespaces. Module
authors are now required to import the namespaces they need.
Some of the main motivations of this feature include: allowing kernel
developers to better manage the export surface, allow subsystem
maintainers to explicitly state that usage of some exported symbols
should only be limited to certain users (think: inter-module or
inter-driver symbols, debugging symbols, etc), as well as more easily
limiting the availability of namespaced symbols to other parts of the
kernel. With the module import requirement, it is also easier to spot
the misuse of exported symbols during patch review. Two new macros are
introduced: EXPORT_SYMBOL_NS() and EXPORT_SYMBOL_NS_GPL(). The API is
thoroughly documented in Documentation/kbuild/namespaces.rst.
- Some small code and kbuild cleanups here and there.
-----BEGIN PGP SIGNATURE-----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=72Uy
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull modules updates from Jessica Yu:
"The main bulk of this pull request introduces a new exported symbol
namespaces feature. The number of exported symbols is increasingly
growing with each release (we're at about 31k exports as of 5.3-rc7)
and we currently have no way of visualizing how these symbols are
"clustered" or making sense of this huge export surface.
Namespacing exported symbols allows kernel developers to more
explicitly partition and categorize exported symbols, as well as more
easily limiting the availability of namespaced symbols to other parts
of the kernel. For starters, we have introduced the USB_STORAGE
namespace to demonstrate the API's usage. I have briefly summarized
the feature and its main motivations in the tag below.
Summary:
- Introduce exported symbol namespaces.
This new feature allows subsystem maintainers to partition and
categorize their exported symbols into explicit namespaces. Module
authors are now required to import the namespaces they need.
Some of the main motivations of this feature include: allowing
kernel developers to better manage the export surface, allow
subsystem maintainers to explicitly state that usage of some
exported symbols should only be limited to certain users (think:
inter-module or inter-driver symbols, debugging symbols, etc), as
well as more easily limiting the availability of namespaced symbols
to other parts of the kernel.
With the module import requirement, it is also easier to spot the
misuse of exported symbols during patch review.
Two new macros are introduced: EXPORT_SYMBOL_NS() and
EXPORT_SYMBOL_NS_GPL(). The API is thoroughly documented in
Documentation/kbuild/namespaces.rst.
- Some small code and kbuild cleanups here and there"
* tag 'modules-for-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
module: Remove leftover '#undef' from export header
module: remove unneeded casts in cmp_name()
module: move CONFIG_UNUSED_SYMBOLS to the sub-menu of MODULES
module: remove redundant 'depends on MODULES'
module: Fix link failure due to invalid relocation on namespace offset
usb-storage: export symbols in USB_STORAGE namespace
usb-storage: remove single-use define for debugging
docs: Add documentation for Symbol Namespaces
scripts: Coccinelle script for namespace dependencies.
modpost: add support for generating namespace dependencies
export: allow definition default namespaces in Makefiles or sources
module: add config option MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS
modpost: add support for symbol namespaces
module: add support for symbol namespaces.
export: explicitly align struct kernel_symbol
module: support reading multiple values per modinfo tag
- virtio support
- Fixes for our new time travel mode
- Various improvements to make lockdep and kasan work better
- SPDX header updates
-----BEGIN PGP SIGNATURE-----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=oxpp
-----END PGP SIGNATURE-----
Merge tag 'for-linus-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml
Pull UML updates from Richard Weinberger:
- virtio support
- fixes for our new time travel mode
- various improvements to make lockdep and kasan work better
- SPDX header updates
* tag 'for-linus-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rw/uml: (25 commits)
um: irq: Fix LAST_IRQ usage in init_IRQ()
um: Add SPDX headers for files in arch/um/include
um: Add SPDX headers for files in arch/um/os-Linux
um: Add SPDX headers to files in arch/um/kernel/
um: Add SPDX headers for files in arch/um/drivers
um: virtio: Implement VHOST_USER_PROTOCOL_F_REPLY_ACK
um: virtio: Implement VHOST_USER_PROTOCOL_F_SLAVE_REQ
um: drivers: Add virtio vhost-user driver
um: Use real DMA barriers
um: Don't use generic barrier.h
um: time-travel: Restrict time update in IRQ handler
um: time-travel: Fix periodic timers
um: Enable CONFIG_CONSTRUCTORS
um: Place (soft)irq text with macros
um: Fix VDSO compiler warning
um: Implement TRACE_IRQFLAGS_SUPPORT
um: Remove misleading #define ARCh_IRQ_ENABLED
um: Avoid using uninitialized regs
um: Remove sig_info[SIGALRM]
um: Error handling fixes in vector drivers
...
This is more cleanup and consolidation of the hmm APIs and the very
strongly related mmu_notifier interfaces. Many places across the tree
using these interfaces are touched in the process. Beyond that a cleanup
to the page walker API and a few memremap related changes round out the
series:
- General improvement of hmm_range_fault() and related APIs, more
documentation, bug fixes from testing, API simplification &
consolidation, and unused API removal
- Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE, and
make them internal kconfig selects
- Hoist a lot of code related to mmu notifier attachment out of drivers by
using a refcount get/put attachment idiom and remove the convoluted
mmu_notifier_unregister_no_release() and related APIs.
- General API improvement for the migrate_vma API and revision of its only
user in nouveau
- Annotate mmu_notifiers with lockdep and sleeping region debugging
Two series unrelated to HMM or mmu_notifiers came along due to
dependencies:
- Allow pagemap's memremap_pages family of APIs to work without providing
a struct device
- Make walk_page_range() and related use a constant structure for function
pointers
-----BEGIN PGP SIGNATURE-----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=FRGg
-----END PGP SIGNATURE-----
Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull hmm updates from Jason Gunthorpe:
"This is more cleanup and consolidation of the hmm APIs and the very
strongly related mmu_notifier interfaces. Many places across the tree
using these interfaces are touched in the process. Beyond that a
cleanup to the page walker API and a few memremap related changes
round out the series:
- General improvement of hmm_range_fault() and related APIs, more
documentation, bug fixes from testing, API simplification &
consolidation, and unused API removal
- Simplify the hmm related kconfigs to HMM_MIRROR and DEVICE_PRIVATE,
and make them internal kconfig selects
- Hoist a lot of code related to mmu notifier attachment out of
drivers by using a refcount get/put attachment idiom and remove the
convoluted mmu_notifier_unregister_no_release() and related APIs.
- General API improvement for the migrate_vma API and revision of its
only user in nouveau
- Annotate mmu_notifiers with lockdep and sleeping region debugging
Two series unrelated to HMM or mmu_notifiers came along due to
dependencies:
- Allow pagemap's memremap_pages family of APIs to work without
providing a struct device
- Make walk_page_range() and related use a constant structure for
function pointers"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (75 commits)
libnvdimm: Enable unit test infrastructure compile checks
mm, notifier: Catch sleeping/blocking for !blockable
kernel.h: Add non_block_start/end()
drm/radeon: guard against calling an unpaired radeon_mn_unregister()
csky: add missing brackets in a macro for tlb.h
pagewalk: use lockdep_assert_held for locking validation
pagewalk: separate function pointers from iterator data
mm: split out a new pagewalk.h header from mm.h
mm/mmu_notifiers: annotate with might_sleep()
mm/mmu_notifiers: prime lockdep
mm/mmu_notifiers: add a lockdep map for invalidate_range_start/end
mm/mmu_notifiers: remove the __mmu_notifier_invalidate_range_start/end exports
mm/hmm: hmm_range_fault() infinite loop
mm/hmm: hmm_range_fault() NULL pointer bug
mm/hmm: fix hmm_range_fault()'s handling of swapped out pages
mm/mmu_notifiers: remove unregister_no_release
RDMA/odp: remove ib_ucontext from ib_umem
RDMA/odp: use mmu_notifier_get/put for 'struct ib_ucontext_per_mm'
RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr
RDMA/mlx5: Use ib_umem_start instead of umem.address
...
-----BEGIN PGP SIGNATURE-----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=Ui4A
-----END PGP SIGNATURE-----
Merge tag 'printk-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk
Pull printk updates from Petr Mladek:
- Fix off-by-one error when calculating messages that might fit into
kmsg buffer. It causes occasional omitting of the last message.
- Add missing pointer check in %pD format modifier handling.
- Some clean up
* tag 'printk-for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/pmladek/printk:
ABI: Update dev-kmsg documentation to match current kernel behaviour
printk: Replace strncmp() with str_has_prefix()
lib/test_printf: Remove obvious comments from %pd and %pD tests
lib/test_printf: Add test of null/invalid pointer dereference for dentry
vsprintf: Prevent crash when dereferencing invalid pointers for %pD
printk: Do not lose last line in kmsg buffer dump
* Now that wq->rescuer may be cleared while rescuer is still there,
switch show_pwq() debug printout to test worker->rescue_wq to
identify rescuers intead of testing wq->rescuer.
* Update comment on ->rescuer locking.
Signed-off-by: Tejun Heo <tj@kernel.org>
Suggested-by: Lai Jiangshan <jiangshanlai@gmail.com>
Fix typos in a few functions' documentation comments.
Signed-off-by: Roy Ben Shlomo <royb@sentinelone.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: royb@sentinelone.com
Link: http://lore.kernel.org/lkml/20190920171254.31373-1-royb@sentinelone.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
- Initial support for running on a system with an Ultravisor, which is software
that runs below the hypervisor and protects guests against some attacks by
the hypervisor.
- Support for building the kernel to run as a "Secure Virtual Machine", ie. as
a guest capable of running on a system with an Ultravisor.
- Some changes to our DMA code on bare metal, to allow devices with medium
sized DMA masks (> 32 && < 59 bits) to use more than 2GB of DMA space.
- Support for firmware assisted crash dumps on bare metal (powernv).
- Two series fixing bugs in and refactoring our PCI EEH code.
- A large series refactoring our exception entry code to use gas macros, both
to make it more readable and also enable some future optimisations.
As well as many cleanups and other minor features & fixups.
Thanks to:
Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh
Kumar K.V, Anju T Sudhakar, Anshuman Khandual, Balbir Singh, Benjamin
Herrenschmidt, Cédric Le Goater, Christophe JAILLET, Christophe Leroy,
Christopher M. Riedl, Christoph Hellwig, Claudio Carvalho, Daniel Axtens,
David Gibson, David Hildenbrand, Desnes A. Nunes do Rosario, Ganesh Goudar,
Gautham R. Shenoy, Greg Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari
Bathini, Joakim Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras,
Lianbo Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan Chancellor,
Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver O'Halloran, Qian Cai, Ram
Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm, Sam Bobroff, Santosh Sivaraj,
Segher Boessenkool, Sukadev Bhattiprolu, Thiago Bauermann, Thiago Jung
Bauermann, Thomas Gleixner, Tom Lendacky, Vasant Hegde.
-----BEGIN PGP SIGNATURE-----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=WlW+
-----END PGP SIGNATURE-----
Merge tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
"This is a bit late, partly due to me travelling, and partly due to a
power outage knocking out some of my test systems *while* I was
travelling.
- Initial support for running on a system with an Ultravisor, which
is software that runs below the hypervisor and protects guests
against some attacks by the hypervisor.
- Support for building the kernel to run as a "Secure Virtual
Machine", ie. as a guest capable of running on a system with an
Ultravisor.
- Some changes to our DMA code on bare metal, to allow devices with
medium sized DMA masks (> 32 && < 59 bits) to use more than 2GB of
DMA space.
- Support for firmware assisted crash dumps on bare metal (powernv).
- Two series fixing bugs in and refactoring our PCI EEH code.
- A large series refactoring our exception entry code to use gas
macros, both to make it more readable and also enable some future
optimisations.
As well as many cleanups and other minor features & fixups.
Thanks to: Adam Zerella, Alexey Kardashevskiy, Alistair Popple, Andrew
Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anshuman Khandual,
Balbir Singh, Benjamin Herrenschmidt, Cédric Le Goater, Christophe
JAILLET, Christophe Leroy, Christopher M. Riedl, Christoph Hellwig,
Claudio Carvalho, Daniel Axtens, David Gibson, David Hildenbrand,
Desnes A. Nunes do Rosario, Ganesh Goudar, Gautham R. Shenoy, Greg
Kurz, Guerney Hunt, Gustavo Romero, Halil Pasic, Hari Bathini, Joakim
Tjernlund, Jonathan Neuschafer, Jordan Niethe, Leonardo Bras, Lianbo
Jiang, Madhavan Srinivasan, Mahesh Salgaonkar, Mahesh Salgaonkar,
Masahiro Yamada, Maxiwell S. Garcia, Michael Anderson, Nathan
Chancellor, Nathan Lynch, Naveen N. Rao, Nicholas Piggin, Oliver
O'Halloran, Qian Cai, Ram Pai, Ravi Bangoria, Reza Arbab, Ryan Grimm,
Sam Bobroff, Santosh Sivaraj, Segher Boessenkool, Sukadev Bhattiprolu,
Thiago Bauermann, Thiago Jung Bauermann, Thomas Gleixner, Tom
Lendacky, Vasant Hegde"
* tag 'powerpc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (264 commits)
powerpc/mm/mce: Keep irqs disabled during lockless page table walk
powerpc: Use ftrace_graph_ret_addr() when unwinding
powerpc/ftrace: Enable HAVE_FUNCTION_GRAPH_RET_ADDR_PTR
ftrace: Look up the address of return_to_handler() using helpers
powerpc: dump kernel log before carrying out fadump or kdump
docs: powerpc: Add missing documentation reference
powerpc/xmon: Fix output of XIVE IPI
powerpc/xmon: Improve output of XIVE interrupts
powerpc/mm/radix: remove useless kernel messages
powerpc/fadump: support holes in kernel boot memory area
powerpc/fadump: remove RMA_START and RMA_END macros
powerpc/fadump: update documentation about option to release opalcore
powerpc/fadump: consider f/w load area
powerpc/opalcore: provide an option to invalidate /sys/firmware/opal/core file
powerpc/opalcore: export /sys/firmware/opal/core for analysing opal crashes
powerpc/fadump: update documentation about CONFIG_PRESERVE_FA_DUMP
powerpc/fadump: add support to preserve crash data on FADUMP disabled kernel
powerpc/fadump: improve how crashed kernel's memory is reserved
powerpc/fadump: consider reserved ranges while releasing memory
powerpc/fadump: make crash memory ranges array allocation generic
...
- Addition of multiprobes to kprobe and uprobe events
Allows for more than one probe attached to the same location
- Addition of adding immediates to probe parameters
- Clean up of the recordmcount.c code. This brings us closer
to merging recordmcount into objtool, and reuse code.
- Other small clean ups
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXYQoqhQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qlIxAP9VVABbpuvOYqxKuFgyP62ituSXPLkL
gZv4I5Zse4b6/gD/eksFXY/OHo7jp6aQiHvxotUkAiFFE9iHzi0JscdMJgo=
=WqrT
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- Addition of multiprobes to kprobe and uprobe events (allows for more
than one probe attached to the same location)
- Addition of adding immediates to probe parameters
- Clean up of the recordmcount.c code. This brings us closer to merging
recordmcount into objtool, and reuse code.
- Other small clean ups
* tag 'trace-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
selftests/ftrace: Update kprobe event error testcase
tracing/probe: Reject exactly same probe event
tracing/probe: Fix to allow user to enable events on unloaded modules
selftests/ftrace: Select an existing function in kprobe_eventname test
tracing/kprobe: Fix NULL pointer access in trace_porbe_unlink()
tracing: Make sure variable reference alias has correct var_ref_idx
tracing: Be more clever when dumping hex in __print_hex()
ftrace: Simplify ftrace hash lookup code in clear_func_from_hash()
tracing: Add "gfp_t" support in synthetic_events
tracing: Rename tracing_reset() to tracing_reset_cpu()
tracing: Document the stack trace algorithm in the comments
tracing/arm64: Have max stack tracer handle the case of return address after data
recordmcount: Clarify what cleanup() does
recordmcount: Remove redundant cleanup() calls
recordmcount: Kernel style formatting
recordmcount: Kernel style function signature formatting
recordmcount: Rewrite error/success handling
selftests/ftrace: Add syntax error test for multiprobe
selftests/ftrace: Add syntax error test for immediates
selftests/ftrace: Add a testcase for kprobe multiprobe event
...
It has been a quiet dev cycle for kgdb. There has been some good stuff
for kdb on the mailing list but unfortunately the patches caused a
couple of problems with the kdb pager so I had to drop those and they
will have to wait for next time!
That just leaves us with just a couple of very tiny clean ups for now:
* Fix a broken comment
* Use str_has_prefix() for the grep "pipe" in kdb
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
-----BEGIN PGP SIGNATURE-----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=oIVA
-----END PGP SIGNATURE-----
Merge tag 'kgdb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux
Pull kgdb updates from Daniel Thompson:
"It has been a quiet dev cycle for kgdb. There has been some good stuff
for kdb on the mailing list but unfortunately the patches caused a
couple of problems with the kdb pager so I had to drop those and they
will have to wait for next time!
That just leaves us with just a couple of very tiny clean ups for now:
- Fix a broken comment
- Use str_has_prefix() for the grep "pipe" in kdb"
* tag 'kgdb-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/danielt/linux:
kgdb: fix comment regarding static function
kdb: Replace strncmp with str_has_prefix
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination
- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule
- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build
in unclean source tree
- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_<basetarget>.o to take the relative path to $(obj)
instead of the basename
- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols
- misc cleanups
-----BEGIN PGP SIGNATURE-----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=VGqV
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- add modpost warn exported symbols marked as 'static' because 'static'
and EXPORT_SYMBOL is an odd combination
- break the build early if gold linker is used
- optimize the Bison rule to produce .c and .h files by a single
pattern rule
- handle PREEMPT_RT in the module vermagic and UTS_VERSION
- warn CONFIG options leaked to the user-space except existing ones
- make single targets work properly
- rebuild modules when module linker scripts are updated
- split the module final link stage into scripts/Makefile.modfinal
- fix the missed error code in merge_config.sh
- improve the error message displayed on the attempt of the O= build in
unclean source tree
- remove 'clean-dirs' syntax
- disable -Wimplicit-fallthrough warning for Clang
- add CONFIG_CC_OPTIMIZE_FOR_SIZE_O3 for ARC
- remove ARCH_{CPP,A,C}FLAGS variables
- add $(BASH) to run bash scripts
- change *CFLAGS_<basetarget>.o to take the relative path to $(obj)
instead of the basename
- stop suppressing Clang's -Wunused-function warnings when W=1
- fix linux/export.h to avoid genksyms calculating CRC of trimmed
exported symbols
- misc cleanups
* tag 'kbuild-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (63 commits)
genksyms: convert to SPDX License Identifier for lex.l and parse.y
modpost: use __section in the output to *.mod.c
modpost: use MODULE_INFO() for __module_depends
export.h, genksyms: do not make genksyms calculate CRC of trimmed symbols
export.h: remove defined(__KERNEL__), which is no longer needed
kbuild: allow Clang to find unused static inline functions for W=1 build
kbuild: rename KBUILD_ENABLE_EXTRA_GCC_CHECKS to KBUILD_EXTRA_WARN
kbuild: refactor scripts/Makefile.extrawarn
merge_config.sh: ignore unwanted grep errors
kbuild: change *FLAGS_<basetarget>.o to take the path relative to $(obj)
modpost: add NOFAIL to strndup
modpost: add guid_t type definition
kbuild: add $(BASH) to run scripts with bash-extension
kbuild: remove ARCH_{CPP,A,C}FLAGS
kbuild,arc: add CONFIG_CC_OPTIMIZE_FOR_PERFORMANCE_O3 for ARC
kbuild: Do not enable -Wimplicit-fallthrough for clang for now
kbuild: clean up subdir-ymn calculation in Makefile.clean
kbuild: remove unneeded '+' marker from cmd_clean
kbuild: remove clean-dirs syntax
kbuild: check clean srctree even earlier
...
- add dma-mapping and block layer helpers to take care of IOMMU
merging for mmc plus subsequent fixups (Yoshihiro Shimoda)
- rework handling of the pgprot bits for remapping (me)
- take care of the dma direct infrastructure for swiotlb-xen (me)
- improve the dma noncoherent remapping infrastructure (me)
- better defaults for ->mmap, ->get_sgtable and ->get_required_mask (me)
- cleanup mmaping of coherent DMA allocations (me)
- various misc cleanups (Andy Shevchenko, me)
-----BEGIN PGP SIGNATURE-----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=/wGv
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- add dma-mapping and block layer helpers to take care of IOMMU merging
for mmc plus subsequent fixups (Yoshihiro Shimoda)
- rework handling of the pgprot bits for remapping (me)
- take care of the dma direct infrastructure for swiotlb-xen (me)
- improve the dma noncoherent remapping infrastructure (me)
- better defaults for ->mmap, ->get_sgtable and ->get_required_mask
(me)
- cleanup mmaping of coherent DMA allocations (me)
- various misc cleanups (Andy Shevchenko, me)
* tag 'dma-mapping-5.4' of git://git.infradead.org/users/hch/dma-mapping: (41 commits)
mmc: renesas_sdhi_internal_dmac: Add MMC_CAP2_MERGE_CAPABLE
mmc: queue: Fix bigger segments usage
arm64: use asm-generic/dma-mapping.h
swiotlb-xen: merge xen_unmap_single into xen_swiotlb_unmap_page
swiotlb-xen: simplify cache maintainance
swiotlb-xen: use the same foreign page check everywhere
swiotlb-xen: remove xen_swiotlb_dma_mmap and xen_swiotlb_dma_get_sgtable
xen: remove the exports for xen_{create,destroy}_contiguous_region
xen/arm: remove xen_dma_ops
xen/arm: simplify dma_cache_maint
xen/arm: use dev_is_dma_coherent
xen/arm: consolidate page-coherent.h
xen/arm: use dma-noncoherent.h calls for xen-swiotlb cache maintainance
arm: remove wrappers for the generic dma remap helpers
dma-mapping: introduce a dma_common_find_pages helper
dma-mapping: always use VM_DMA_COHERENT for generic DMA remap
vmalloc: lift the arm flag for coherent mappings to common code
dma-mapping: provide a better default ->get_required_mask
dma-mapping: remove the dma_declare_coherent_memory export
remoteproc: don't allow modular build
...
The timer delayed for more than 3 seconds warning was triggered during
testing.
Workqueue: events_unbound sched_tick_remote
RIP: 0010:sched_tick_remote+0xee/0x100
...
Call Trace:
process_one_work+0x18c/0x3a0
worker_thread+0x30/0x380
kthread+0x113/0x130
ret_from_fork+0x22/0x40
The reason is that the code in collect_expired_timers() uses jiffies
unprotected:
if (next_event > jiffies)
base->clk = jiffies;
As the compiler is allowed to reload the value base->clk can advance
between the check and the store and in the worst case advance farther than
next event. That causes the timer expiry to be delayed until the wheel
pointer wraps around.
Convert the code to use READ_ONCE()
Fixes: 236968383c ("timers: Optimize collect_expired_timers() for NOHZ")
Signed-off-by: Li RongQing <lirongqing@baidu.com>
Signed-off-by: Liang ZhiCheng <liangzhicheng@baidu.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1568894687-14499-1-git-send-email-lirongqing@baidu.com
Reject exactly same probe events as existing probes.
Multiprobe allows user to define multiple probes on same
event. If user appends a probe which exactly same definition
(same probe address and same arguments) on existing event,
the event will record same probe information twice.
That can be confusing users, so reject it.
Link: http://lkml.kernel.org/r/156879694602.31056.5533024778165036763.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Fix to allow user to enable probe events on unloaded modules.
This operations was allowed before commit 60d53e2c3b ("tracing/probe:
Split trace_event related data from trace_probe"), because if users
need to probe module init functions, they have to enable those probe
events before loading module.
Link: http://lkml.kernel.org/r/156879693733.31056.9331322616994665167.stgit@devnote2
Cc: stable@vger.kernel.org
Fixes: 60d53e2c3b ("tracing/probe: Split trace_event related data from trace_probe")
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
vmlinux BTF has enums that are 8 byte and 1 byte in size.
2 byte enum is a valid construct as well.
Fix BTF enum verification to accept those sizes.
Fixes: 69b693f0ae ("bpf: btf: Introduce BPF Type Format (BTF)")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Convert the bpf filesystem to the new internal mount API as the old
one will be obsoleted and removed. This allows greater flexibility in
communication of mount parameters between userspace, the VFS and the
filesystem.
See Documentation/filesystems/mount_api.txt for more information.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Alexei Starovoitov <ast@kernel.org>
cc: Daniel Borkmann <daniel@iogearbox.net>
cc: Martin KaFai Lau <kafai@fb.com>
cc: Song Liu <songliubraving@fb.com>
cc: Yonghong Song <yhs@fb.com>
cc: netdev@vger.kernel.org
cc: bpf@vger.kernel.org
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Before actually destrying a workqueue, destroy_workqueue() checks
whether it's actually idle. If it isn't, it prints out a bunch of
warning messages and leaves the workqueue dangling. It unfortunately
has a couple issues.
* Mayday list queueing increments pwq's refcnts which gets detected as
busy and fails the sanity checks. However, because mayday list
queueing is asynchronous, this condition can happen without any
actual work items left in the workqueue.
* Sanity check failure leaves the sysfs interface behind too which can
lead to init failure of newer instances of the workqueue.
This patch fixes the above two by
* If a workqueue has a rescuer, disable and kill the rescuer before
sanity checks. Disabling and killing is guaranteed to flush the
existing mayday list.
* Remove sysfs interface before sanity checks.
Signed-off-by: Tejun Heo <tj@kernel.org>
Reported-by: Marcin Pawlowski <mpawlowski@fb.com>
Reported-by: "Williams, Gerald S" <gerald.s.williams@intel.com>
Cc: stable@vger.kernel.org
Pull networking updates from David Miller:
1) Support IPV6 RA Captive Portal Identifier, from Maciej Żenczykowski.
2) Use bio_vec in the networking instead of custom skb_frag_t, from
Matthew Wilcox.
3) Make use of xmit_more in r8169 driver, from Heiner Kallweit.
4) Add devmap_hash to xdp, from Toke Høiland-Jørgensen.
5) Support all variants of 5750X bnxt_en chips, from Michael Chan.
6) More RTNL avoidance work in the core and mlx5 driver, from Vlad
Buslov.
7) Add TCP syn cookies bpf helper, from Petar Penkov.
8) Add 'nettest' to selftests and use it, from David Ahern.
9) Add extack support to drop_monitor, add packet alert mode and
support for HW drops, from Ido Schimmel.
10) Add VLAN offload to stmmac, from Jose Abreu.
11) Lots of devm_platform_ioremap_resource() conversions, from
YueHaibing.
12) Add IONIC driver, from Shannon Nelson.
13) Several kTLS cleanups, from Jakub Kicinski.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1930 commits)
mlxsw: spectrum_buffers: Add the ability to query the CPU port's shared buffer
mlxsw: spectrum: Register CPU port with devlink
mlxsw: spectrum_buffers: Prevent changing CPU port's configuration
net: ena: fix incorrect update of intr_delay_resolution
net: ena: fix retrieval of nonadaptive interrupt moderation intervals
net: ena: fix update of interrupt moderation register
net: ena: remove all old adaptive rx interrupt moderation code from ena_com
net: ena: remove ena_restore_ethtool_params() and relevant fields
net: ena: remove old adaptive interrupt moderation code from ena_netdev
net: ena: remove code duplication in ena_com_update_nonadaptive_moderation_interval _*()
net: ena: enable the interrupt_moderation in driver_supported_features
net: ena: reimplement set/get_coalesce()
net: ena: switch to dim algorithm for rx adaptive interrupt moderation
net: ena: add intr_moder_rx_interval to struct ena_com_dev and use it
net: phy: adin: implement Energy Detect Powerdown mode via phy-tunable
ethtool: implement Energy Detect Powerdown support via phy-tunable
xen-netfront: do not assume sk_buff_head list is empty in error handling
s390/ctcm: Delete unnecessary checks before the macro call “dev_kfree_skb”
net: ena: don't wake up tx queue when down
drop_monitor: Better sanitize notified packets
...
Pull crypto updates from Herbert Xu:
"API:
- Add the ability to abort a skcipher walk.
Algorithms:
- Fix XTS to actually do the stealing.
- Add library helpers for AES and DES for single-block users.
- Add library helpers for SHA256.
- Add new DES key verification helper.
- Add surrounding bits for ESSIV generator.
- Add accelerations for aegis128.
- Add test vectors for lzo-rle.
Drivers:
- Add i.MX8MQ support to caam.
- Add gcm/ccm/cfb/ofb aes support in inside-secure.
- Add ofb/cfb aes support in media-tek.
- Add HiSilicon ZIP accelerator support.
Others:
- Fix potential race condition in padata.
- Use unbound workqueues in padata"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (311 commits)
crypto: caam - Cast to long first before pointer conversion
crypto: ccree - enable CTS support in AES-XTS
crypto: inside-secure - Probe transform record cache RAM sizes
crypto: inside-secure - Base RD fetchcount on actual RD FIFO size
crypto: inside-secure - Base CD fetchcount on actual CD FIFO size
crypto: inside-secure - Enable extended algorithms on newer HW
crypto: inside-secure: Corrected configuration of EIP96_TOKEN_CTRL
crypto: inside-secure - Add EIP97/EIP197 and endianness detection
padata: remove cpu_index from the parallel_queue
padata: unbind parallel jobs from specific CPUs
padata: use separate workqueues for parallel and serial work
padata, pcrypt: take CPU hotplug lock internally in padata_alloc_possible
crypto: pcrypt - remove padata cpumask notifier
padata: make padata_do_parallel find alternate callback CPU
workqueue: require CPU hotplug read exclusion for apply_workqueue_attrs
workqueue: unconfine alloc/apply/free_workqueue_attrs()
padata: allocate workqueue internally
arm64: dts: imx8mq: Add CAAM node
random: Use wait_event_freezable() in add_hwgenerator_randomness()
crypto: ux500 - Fix COMPILE_TEST warnings
...
- Rework the main suspend-to-idle control flow to avoid repeating
"noirq" device resume and suspend operations in case of spurious
wakeups from the ACPI EC and decouple the ACPI EC wakeups support
from the LPS0 _DSM support (Rafael Wysocki).
- Extend the wakeup sources framework to expose wakeup sources as
device objects in sysfs (Tri Vo, Stephen Boyd).
- Expose system suspend statistics in sysfs (Kalesh Singh).
- Introduce a new haltpoll cpuidle driver and a new matching
governor for virtualized guests wanting to do guest-side polling
in the idle loop (Marcelo Tosatti, Joao Martins, Wanpeng Li,
Stephen Rothwell).
- Fix the menu and teo cpuidle governors to allow the scheduler tick
to be stopped if PM QoS is used to limit the CPU idle state exit
latency in some cases (Rafael Wysocki).
- Increase the resolution of the play_idle() argument to microseconds
for more fine-grained injection of CPU idle cycles (Daniel Lezcano).
- Switch over some users of cpuidle notifiers to the new QoS-based
frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY
policy notifier events (Viresh Kumar).
- Add new cpufreq driver based on nvmem for sun50i (Yangtao Li).
- Add support for MT8183 and MT8516 to the mediatek cpufreq driver
(Andrew-sh.Cheng, Fabien Parent).
- Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson
Huang).
- Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz).
- Update the qcom cpufreq driver (among other things, to make it
easier to extend and to use kryo cpufreq for other nvmem-based
SoCs) and add qcs404 support to it (Niklas Cassel, Douglas
RAILLARD, Sibi Sankar, Sricharan R).
- Fix assorted issues and make assorted minor improvements in the
cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli,
Gustavo Silva, Hariprasad Kelam).
- Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd
Bergmann).
- Add new Exynos PPMU events to devfreq events and extend that
mechanism (Lukasz Luba).
- Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny).
- Improve devfreq documentation and governor code, fix spelling
typos in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard
Crestez, MyungJoo Ham, Gaël PORTAY).
- Add regulators enable and disable to the OPP (operating performance
points) framework (Kamil Konieczny).
- Update the OPP framework to support multiple opp-suspend properties
(Anson Huang).
- Fix assorted issues and make assorted minor improvements in the OPP
code (Niklas Cassel, Viresh Kumar, Yue Hu).
- Clean up the generic power domains (genpd) framework (Ulf Hansson).
- Clean up assorted pieces of power management code and documentation
(Akinobu Mita, Amit Kucheria, Chuhong Yuan).
- Update the pm-graph tool to version 5.5 including multiple fixes
and improvements (Todd Brandt).
- Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven,
Sébastien Szymanski).
-----BEGIN PGP SIGNATURE-----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=TBDQ
-----END PGP SIGNATURE-----
Merge tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These include a rework of the main suspend-to-idle code flow (related
to the handling of spurious wakeups), a switch over of several users
of cpufreq notifiers to QoS-based limits, a new devfreq driver for
Tegra20, a new cpuidle driver and governor for virtualized guests, an
extension of the wakeup sources framework to expose wakeup sources as
device objects in sysfs, and more.
Specifics:
- Rework the main suspend-to-idle control flow to avoid repeating
"noirq" device resume and suspend operations in case of spurious
wakeups from the ACPI EC and decouple the ACPI EC wakeups support
from the LPS0 _DSM support (Rafael Wysocki).
- Extend the wakeup sources framework to expose wakeup sources as
device objects in sysfs (Tri Vo, Stephen Boyd).
- Expose system suspend statistics in sysfs (Kalesh Singh).
- Introduce a new haltpoll cpuidle driver and a new matching governor
for virtualized guests wanting to do guest-side polling in the idle
loop (Marcelo Tosatti, Joao Martins, Wanpeng Li, Stephen Rothwell).
- Fix the menu and teo cpuidle governors to allow the scheduler tick
to be stopped if PM QoS is used to limit the CPU idle state exit
latency in some cases (Rafael Wysocki).
- Increase the resolution of the play_idle() argument to microseconds
for more fine-grained injection of CPU idle cycles (Daniel
Lezcano).
- Switch over some users of cpuidle notifiers to the new QoS-based
frequency limits and drop the CPUFREQ_ADJUST and CPUFREQ_NOTIFY
policy notifier events (Viresh Kumar).
- Add new cpufreq driver based on nvmem for sun50i (Yangtao Li).
- Add support for MT8183 and MT8516 to the mediatek cpufreq driver
(Andrew-sh.Cheng, Fabien Parent).
- Add i.MX8MN support to the imx-cpufreq-dt cpufreq driver (Anson
Huang).
- Add qcs404 to cpufreq-dt-platdev blacklist (Jorge Ramirez-Ortiz).
- Update the qcom cpufreq driver (among other things, to make it
easier to extend and to use kryo cpufreq for other nvmem-based
SoCs) and add qcs404 support to it (Niklas Cassel, Douglas
RAILLARD, Sibi Sankar, Sricharan R).
- Fix assorted issues and make assorted minor improvements in the
cpufreq code (Colin Ian King, Douglas RAILLARD, Florian Fainelli,
Gustavo Silva, Hariprasad Kelam).
- Add new devfreq driver for NVidia Tegra20 (Dmitry Osipenko, Arnd
Bergmann).
- Add new Exynos PPMU events to devfreq events and extend that
mechanism (Lukasz Luba).
- Fix and clean up the exynos-bus devfreq driver (Kamil Konieczny).
- Improve devfreq documentation and governor code, fix spelling typos
in devfreq (Ezequiel Garcia, Krzysztof Kozlowski, Leonard Crestez,
MyungJoo Ham, Gaël PORTAY).
- Add regulators enable and disable to the OPP (operating performance
points) framework (Kamil Konieczny).
- Update the OPP framework to support multiple opp-suspend properties
(Anson Huang).
- Fix assorted issues and make assorted minor improvements in the OPP
code (Niklas Cassel, Viresh Kumar, Yue Hu).
- Clean up the generic power domains (genpd) framework (Ulf Hansson).
- Clean up assorted pieces of power management code and documentation
(Akinobu Mita, Amit Kucheria, Chuhong Yuan).
- Update the pm-graph tool to version 5.5 including multiple fixes
and improvements (Todd Brandt).
- Update the cpupower utility (Benjamin Weis, Geert Uytterhoeven,
Sébastien Szymanski)"
* tag 'pm-5.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (126 commits)
cpuidle-haltpoll: Enable kvm guest polling when dedicated physical CPUs are available
cpuidle-haltpoll: do not set an owner to allow modunload
cpuidle-haltpoll: return -ENODEV on modinit failure
cpuidle-haltpoll: set haltpoll as preferred governor
cpuidle: allow governor switch on cpuidle_register_driver()
PM: runtime: Documentation: add runtime_status ABI document
pm-graph: make setVal unbuffered again for python2 and python3
powercap: idle_inject: Use higher resolution for idle injection
cpuidle: play_idle: Increase the resolution to usec
cpuidle-haltpoll: vcpu hotplug support
cpufreq: Add qcs404 to cpufreq-dt-platdev blacklist
cpufreq: qcom: Add support for qcs404 on nvmem driver
cpufreq: qcom: Refactor the driver to make it easier to extend
cpufreq: qcom: Re-organise kryo cpufreq to use it for other nvmem based qcom socs
dt-bindings: opp: Add qcom-opp bindings with properties needed for CPR
dt-bindings: opp: qcom-nvmem: Support pstates provided by a power domain
Documentation: cpufreq: Update policy notifier documentation
cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events
PM / Domains: Verify PM domain type in dev_pm_genpd_set_performance_state()
PM / Domains: Simplify genpd_lookup_dev()
...
Pull cgroup updates from Tejun Heo:
"Three minor cleanup patches"
* 'for-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
Use kvmalloc in cgroups-v1
cgroup: minor tweak for logic to get cgroup css
cgroup: Replace a seq_printf() call by seq_puts() in cgroup_print_ss_mask()
Pull core timer updates from Thomas Gleixner:
"Timers and timekeeping updates:
- A large overhaul of the posix CPU timer code which is a preparation
for moving the CPU timer expiry out into task work so it can be
properly accounted on the task/process.
An update to the bogus permission checks will come later during the
merge window as feedback was not complete before heading of for
travel.
- Switch the timerqueue code to use cached rbtrees and get rid of the
homebrewn caching of the leftmost node.
- Consolidate hrtimer_init() + hrtimer_init_sleeper() calls into a
single function
- Implement the separation of hrtimers to be forced to expire in hard
interrupt context even when PREEMPT_RT is enabled and mark the
affected timers accordingly.
- Implement a mechanism for hrtimers and the timer wheel to protect
RT against priority inversion and live lock issues when a (hr)timer
which should be canceled is currently executing the callback.
Instead of infinitely spinning, the task which tries to cancel the
timer blocks on a per cpu base expiry lock which is held and
released by the (hr)timer expiry code.
- Enable the Hyper-V TSC page based sched_clock for Hyper-V guests
resulting in faster access to timekeeping functions.
- Updates to various clocksource/clockevent drivers and their device
tree bindings.
- The usual small improvements all over the place"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (101 commits)
posix-cpu-timers: Fix permission check regression
posix-cpu-timers: Always clear head pointer on dequeue
hrtimer: Add a missing bracket and hide `migration_base' on !SMP
posix-cpu-timers: Make expiry_active check actually work correctly
posix-timers: Unbreak CONFIG_POSIX_TIMERS=n build
tick: Mark sched_timer to expire in hard interrupt context
hrtimer: Add kernel doc annotation for HRTIMER_MODE_HARD
x86/hyperv: Hide pv_ops access for CONFIG_PARAVIRT=n
posix-cpu-timers: Utilize timerqueue for storage
posix-cpu-timers: Move state tracking to struct posix_cputimers
posix-cpu-timers: Deduplicate rlimit handling
posix-cpu-timers: Remove pointless comparisons
posix-cpu-timers: Get rid of 64bit divisions
posix-cpu-timers: Consolidate timer expiry further
posix-cpu-timers: Get rid of zero checks
rlimit: Rewrite non-sensical RLIMIT_CPU comment
posix-cpu-timers: Respect INFINITY for hard RTTIME limit
posix-cpu-timers: Switch thread group sampling to array
posix-cpu-timers: Restructure expiry array
posix-cpu-timers: Remove cputime_expires
...
Pull core irq updates from Thomas Gleixner:
"Updates from the irq departement:
- Update the interrupt spreading code so it handles numa node with
different CPU counts properly.
- A large overhaul of the ARM GiCv3 driver to support new PPI and SPI
ranges.
- Conversion of all alloc_fwnode() users to use physical addresses
instead of virtual addresses so the virtual addresses are not
leaked. The physical address is sufficient to identify the
associated interrupt chip.
- Add support for Marvel MMP3, Amlogic Meson SM1 interrupt chips.
- Enforce interrupt threading at compile time if RT is enabled.
- Small updates and improvements all over the place"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (37 commits)
irqchip/gic-v3-its: Fix LPI release for Multi-MSI devices
irqchip/uniphier-aidet: Use devm_platform_ioremap_resource()
irqdomain: Add the missing assignment of domain->fwnode for named fwnode
irqchip/mmp: Coexist with GIC root IRQ controller
irqchip/mmp: Mask off interrupts from other cores
irqchip/mmp: Add missing chained_irq_{enter,exit}()
irqchip/mmp: Do not use of_address_to_resource() to get mux regs
irqchip/meson-gpio: Add support for meson sm1 SoCs
dt-bindings: interrupt-controller: New binding for the meson sm1 SoCs
genirq/affinity: Remove const qualifier from node_to_cpumask argument
genirq/affinity: Spread vectors on node according to nr_cpu ratio
genirq/affinity: Improve __irq_build_affinity_masks()
irqchip: Remove dev_err() usage after platform_get_irq()
irqchip: Add include guard to irq-partition-percpu.h
irqchip/mmp: Do not call irq_set_default_host() on DT platforms
irqchip/gic-v3-its: Remove the redundant set_bit for lpi_map
irqchip/gic-v3: Add quirks for HIP06/07 invalid GICD_TYPER erratum 161010803
irqchip/gic: Skip DT quirks when evaluating IIDR-based quirks
irqchip/gic-v3: Warn about inconsistent implementations of extended ranges
irqchip/gic-v3: Add EPPI range support
...
Pull CPU hotplug updates from Thomas Gleixner:
"A small update for the SMP hotplug code code:
- Track "booted once" CPUs in a cpumask so the x86 APIC code has an
easy way to decide whether broadcast IPIs are safe to use or not.
- Implement a cpumask_or_equal() helper for the IPI broadcast
evaluation.
The above two changes have been also pulled into the x86/apic
branch for implementing the conditional IPI broadcast feature.
- Cache the number of online CPUs instead of reevaluating it over and
over. num_online_cpus() is an unreliable snapshot anyway except
when it is used outside a cpu hotplug locked region. The cached
access is not changing this, but it's definitely faster than
calculating the bitmap wheight especially in hot paths"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Cache number of online CPUs
cpumask: Implement cpumask_or_equal()
smp/hotplug: Track booted once CPUs in a cpumask
Pull timer fix from Thomas Gleixner:
"A single fix to prevent the alarm timer code from returning ENOTSUPP
to user space.
ENOTSUPP is a purely kernel internal error code related to NFSv3 and
should never be handed back to user space. The risk for ABI breakage
is low as the number of systems which do not have a working RTC is
very limited"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
alarmtimer: Use EOPNOTSUPP instead of ENOTSUPP
Original changelog from Steve Rostedt (except last sentence which
explains the problem, and the Fixes: tag):
I performed a three way histogram with the following commands:
echo 'irq_lat u64 lat pid_t pid' > synthetic_events
echo 'wake_lat u64 lat u64 irqlat pid_t pid' >> synthetic_events
echo 'hist:keys=common_pid:irqts=common_timestamp.usecs if function == 0xffffffff81200580' > events/timer/hrtimer_start/trigger
echo 'hist:keys=common_pid:lat=common_timestamp.usecs-$irqts:onmatch(timer.hrtimer_start).irq_lat($lat,pid) if common_flags & 1' > events/sched/sched_waking/trigger
echo 'hist:keys=pid:wakets=common_timestamp.usecs,irqlat=lat' > events/synthetic/irq_lat/trigger
echo 'hist:keys=next_pid:lat=common_timestamp.usecs-$wakets,irqlat=$irqlat:onmatch(synthetic.irq_lat).wake_lat($lat,$irqlat,next_pid)' > events/sched/sched_switch/trigger
echo 1 > events/synthetic/wake_lat/enable
Basically I wanted to see:
hrtimer_start (calling function tick_sched_timer)
Note:
# grep tick_sched_timer /proc/kallsyms
ffffffff81200580 t tick_sched_timer
And save the time of that, and then record sched_waking if it is called
in interrupt context and with the same pid as the hrtimer_start, it
will record the latency between that and the waking event.
I then look at when the task that is woken is scheduled in, and record
the latency between the wakeup and the task running.
At the end, the wake_lat synthetic event will show the wakeup to
scheduled latency, as well as the irq latency in from hritmer_start to
the wakeup. The problem is that I found this:
<idle>-0 [007] d... 190.485261: wake_lat: lat=27 irqlat=190485230 pid=698
<idle>-0 [005] d... 190.485283: wake_lat: lat=40 irqlat=190485239 pid=10
<idle>-0 [002] d... 190.488327: wake_lat: lat=56 irqlat=190488266 pid=335
<idle>-0 [005] d... 190.489330: wake_lat: lat=64 irqlat=190489262 pid=10
<idle>-0 [003] d... 190.490312: wake_lat: lat=43 irqlat=190490265 pid=77
<idle>-0 [005] d... 190.493322: wake_lat: lat=54 irqlat=190493262 pid=10
<idle>-0 [005] d... 190.497305: wake_lat: lat=35 irqlat=190497267 pid=10
<idle>-0 [005] d... 190.501319: wake_lat: lat=50 irqlat=190501264 pid=10
The irqlat seemed quite large! Investigating this further, if I had
enabled the irq_lat synthetic event, I noticed this:
<idle>-0 [002] d.s. 249.429308: irq_lat: lat=164968 pid=335
<idle>-0 [002] d... 249.429369: wake_lat: lat=55 irqlat=249429308 pid=335
Notice that the timestamp of the irq_lat "249.429308" is awfully
similar to the reported irqlat variable. In fact, all instances were
like this. It appeared that:
irqlat=$irqlat
Wasn't assigning the old $irqlat to the new irqlat variable, but
instead was assigning the $irqts to it.
The issue is that assigning the old $irqlat to the new irqlat variable
creates a variable reference alias, but the alias creation code
forgets to make sure the alias uses the same var_ref_idx to access the
reference.
Link: http://lkml.kernel.org/r/1567375321.5282.12.camel@kernel.org
Cc: Linux Trace Devel <linux-trace-devel@vger.kernel.org>
Cc: linux-rt-users <linux-rt-users@vger.kernel.org>
Cc: stable@vger.kernel.org
Fixes: 7e8b88a30b ("tracing: Add hist trigger support for variable reference aliases")
Reported-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Function ftrace_lookup_ip() will check empty hash table. So we don't
need extra check outside.
Link: http://lkml.kernel.org/r/20190910143336.13472-1-changbin.du@gmail.com
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
cfs_rq_clock_task() was first introduced and used in:
f1b17280ef ("sched: Maintain runnable averages across throttled periods")
Over time its use has been graduately removed by the following commits:
d31b1a66cb ("sched/fair: Factorize PELT update")
2312729688 ("sched/fair: Update scale invariance of PELT")
Today, there is no single user left, so it can be safely removed.
Found via the -Wunused-function build warning.
Signed-off-by: Qian Cai <cai@lca.pw>
Cc: Ben Segall <bsegall@google.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/1568668775-2127-1-git-send-email-cai@lca.pw
[ Rewrote the changelog. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
* pm-opp:
PM / OPP: Correct Documentation about library location
opp: of: Support multiple suspend OPPs defined in DT
dt-bindings: opp: Support multiple opp-suspend properties
opp: core: add regulators enable and disable
opp: Don't decrement uninitialized list_kref
* pm-qos:
PM: QoS: Get rid of unused flags
* acpi-pm:
ACPI: PM: Print debug messages on device power state changes
* pm-domains:
PM / Domains: Verify PM domain type in dev_pm_genpd_set_performance_state()
PM / Domains: Simplify genpd_lookup_dev()
PM / Domains: Align in-parameter names for some genpd functions
* pm-tools:
pm-graph: make setVal unbuffered again for python2 and python3
cpupower: update German translation
tools/power/cpupower: fix 64bit detection when cross-compiling
cpupower: Add missing newline at end of file
pm-graph v5.5
* pm-cpufreq: (36 commits)
cpufreq: Add qcs404 to cpufreq-dt-platdev blacklist
cpufreq: qcom: Add support for qcs404 on nvmem driver
cpufreq: qcom: Refactor the driver to make it easier to extend
cpufreq: qcom: Re-organise kryo cpufreq to use it for other nvmem based qcom socs
dt-bindings: opp: Add qcom-opp bindings with properties needed for CPR
dt-bindings: opp: qcom-nvmem: Support pstates provided by a power domain
Documentation: cpufreq: Update policy notifier documentation
cpufreq: Remove CPUFREQ_ADJUST and CPUFREQ_NOTIFY policy notifier events
sched/cpufreq: Align trace event behavior of fast switching
ACPI: cpufreq: Switch to QoS requests instead of cpufreq notifier
video: pxafb: Remove cpufreq policy notifier
video: sa1100fb: Remove cpufreq policy notifier
arch_topology: Use CPUFREQ_CREATE_POLICY instead of CPUFREQ_NOTIFY
cpufreq: powerpc_cbe: Switch to QoS requests for freq limits
cpufreq: powerpc: macintosh: Switch to QoS requests for freq limits
cpufreq: Print driver name if cpufreq_suspend() fails
cpufreq: mediatek: Add support for mt8183
cpufreq: mediatek: change to regulator_get_optional
cpufreq: imx-cpufreq-dt: Add i.MX8MN support
cpufreq: Use imx-cpufreq-dt for i.MX8MN's speed grading
...
* pm-cpuidle:
cpuidle-haltpoll: Enable kvm guest polling when dedicated physical CPUs are available
cpuidle-haltpoll: do not set an owner to allow modunload
cpuidle-haltpoll: return -ENODEV on modinit failure
cpuidle-haltpoll: set haltpoll as preferred governor
cpuidle: allow governor switch on cpuidle_register_driver()
powercap: idle_inject: Use higher resolution for idle injection
cpuidle: play_idle: Increase the resolution to usec
cpuidle-haltpoll: vcpu hotplug support
cpuidle: teo: Get rid of redundant check in teo_update()
cpuidle: teo: Allow tick to be stopped if PM QoS is used
cpuidle: menu: Allow tick to be stopped if PM QoS is used
cpuidle: header file stubs must be "static inline"
cpuidle-haltpoll: disable host side polling when kvm virtualized
cpuidle: add haltpoll governor
governors: unify last_state_idx
cpuidle: add poll_limit_ns to cpuidle_device structure
add cpuidle-haltpoll driver
* pm-s2idle-rework: (21 commits)
ACPI: PM: s2idle: Always set up EC GPE for system wakeup
ACPI: PM: s2idle: Avoid rearming SCI for wakeup unnecessarily
PM: suspend: Fix platform_suspend_prepare_noirq()
intel-hid: Disable button array during suspend-to-idle
intel-hid: intel-vbtn: Avoid leaking wakeup_mode set
ACPI: PM: s2idle: Execute LPS0 _DSM functions with suspended devices
ACPI: EC: PM: Make acpi_ec_dispatch_gpe() print debug message
ACPI: EC: PM: Consolidate some code depending on PM_SLEEP
ACPI: PM: s2idle: Eliminate acpi_sleep_no_ec_events()
ACPI: PM: s2idle: Switch EC over to polling during "noirq" suspend
ACPI: PM: s2idle: Add acpi.sleep_no_lps0 module parameter
ACPI: PM: s2idle: Rearrange lps0_device_attach()
ACPI: PM: Set up EC GPE for system wakeup from drivers that need it
PM: sleep: Drop dpm_noirq_begin() and dpm_noirq_end()
PM: sleep: Integrate suspend-to-idle with generig suspend flow
PM: sleep: Simplify suspend-to-idle control flow
ACPI: PM: Set s2idle_wakeup earlier and clear it later
PM: sleep: Fix possible overflow in pm_system_cancel_wakeup()
ACPI: EC: Return bool from acpi_ec_dispatch_gpe()
ACPICA: Return u32 from acpi_dispatch_gpe()
...
Pull x86 cpu-feature updates from Ingo Molnar:
- Rework the Intel model names symbols/macros, which were decades of
ad-hoc extensions and added random noise. It's now a coherent, easy
to follow nomenclature.
- Add new Intel CPU model IDs:
- "Tiger Lake" desktop and mobile models
- "Elkhart Lake" model ID
- and the "Lightning Mountain" variant of Airmont, plus support code
- Add the new AVX512_VP2INTERSECT instruction to cpufeatures
- Remove Intel MPX user-visible APIs and the self-tests, because the
toolchain (gcc) is not supporting it going forward. This is the
first, lowest-risk phase of MPX removal.
- Remove X86_FEATURE_MFENCE_RDTSC
- Various smaller cleanups and fixes
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
x86/cpu: Update init data for new Airmont CPU model
x86/cpu: Add new Airmont variant to Intel family
x86/cpu: Add Elkhart Lake to Intel family
x86/cpu: Add Tiger Lake to Intel family
x86: Correct misc typos
x86/intel: Add common OPTDIFFs
x86/intel: Aggregate microserver naming
x86/intel: Aggregate big core graphics naming
x86/intel: Aggregate big core mobile naming
x86/intel: Aggregate big core client naming
x86/cpufeature: Explain the macro duplication
x86/ftrace: Remove mcount() declaration
x86/PCI: Remove superfluous returns from void functions
x86/msr-index: Move AMD MSRs where they belong
x86/cpu: Use constant definitions for CPU models
lib: Remove redundant ftrace flag removal
x86/crash: Remove unnecessary comparison
x86/bitops: Use __builtin_constant_p() directly instead of IS_IMMEDIATE()
x86: Remove X86_FEATURE_MFENCE_RDTSC
x86/mpx: Remove MPX APIs
...
Pull scheduler updates from Ingo Molnar:
- MAINTAINERS: Add Mark Rutland as perf submaintainer, Juri Lelli and
Vincent Guittot as scheduler submaintainers. Add Dietmar Eggemann,
Steven Rostedt, Ben Segall and Mel Gorman as scheduler reviewers.
As perf and the scheduler is getting bigger and more complex,
document the status quo of current responsibilities and interests,
and spread the review pain^H^H^H^H fun via an increase in the Cc:
linecount generated by scripts/get_maintainer.pl. :-)
- Add another series of patches that brings the -rt (PREEMPT_RT) tree
closer to mainline: split the monolithic CONFIG_PREEMPT dependencies
into a new CONFIG_PREEMPTION category that will allow the eventual
introduction of CONFIG_PREEMPT_RT. Still a few more hundred patches
to go though.
- Extend the CPU cgroup controller with uclamp.min and uclamp.max to
allow the finer shaping of CPU bandwidth usage.
- Micro-optimize energy-aware wake-ups from O(CPUS^2) to O(CPUS).
- Improve the behavior of high CPU count, high thread count
applications running under cpu.cfs_quota_us constraints.
- Improve balancing with SCHED_IDLE (SCHED_BATCH) tasks present.
- Improve CPU isolation housekeeping CPU allocation NUMA locality.
- Fix deadline scheduler bandwidth calculations and logic when cpusets
rebuilds the topology, or when it gets deadline-throttled while it's
being offlined.
- Convert the cpuset_mutex to percpu_rwsem, to allow it to be used from
setscheduler() system calls without creating global serialization.
Add new synchronization between cpuset topology-changing events and
the deadline acceptance tests in setscheduler(), which were broken
before.
- Rework the active_mm state machine to be less confusing and more
optimal.
- Rework (simplify) the pick_next_task() slowpath.
- Improve load-balancing on AMD EPYC systems.
- ... and misc cleanups, smaller fixes and improvements - please see
the Git log for more details.
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (53 commits)
sched/psi: Correct overly pessimistic size calculation
sched/fair: Speed-up energy-aware wake-ups
sched/uclamp: Always use 'enum uclamp_id' for clamp_id values
sched/uclamp: Update CPU's refcount on TG's clamp changes
sched/uclamp: Use TG's clamps to restrict TASK's clamps
sched/uclamp: Propagate system defaults to the root group
sched/uclamp: Propagate parent clamps
sched/uclamp: Extend CPU's cgroup controller
sched/topology: Improve load balancing on AMD EPYC systems
arch, ia64: Make NUMA select SMP
sched, perf: MAINTAINERS update, add submaintainers and reviewers
sched/fair: Use rq_lock/unlock in online_fair_sched_group
cpufreq: schedutil: fix equation in comment
sched: Rework pick_next_task() slow-path
sched: Allow put_prev_task() to drop rq->lock
sched/fair: Expose newidle_balance()
sched: Add task_struct pointer to sched_class::set_curr_task
sched: Rework CPU hotplug task selection
sched/{rt,deadline}: Fix set_next_task vs pick_next_task
sched: Fix kerneldoc comment for ia64_set_curr_task
...
Pull perf updates from Ingo Molnar:
"Kernel side changes:
- Improved kbprobes robustness
- Intel PEBS support for PT hardware tracing
- Other Intel PT improvements: high order pages memory footprint
reduction and various related cleanups
- Misc cleanups
The perf tooling side has been very busy in this cycle, with over 300
commits. This is an incomplete high-level summary of the many
improvements done by over 30 developers:
- Lots of updates to the following tools:
'perf c2c'
'perf config'
'perf record'
'perf report'
'perf script'
'perf test'
'perf top'
'perf trace'
- Updates to libperf and libtraceevent, and a consolidation of the
proliferation of x86 instruction decoder libraries.
- Vendor event updates for Intel and PowerPC CPUs,
- Updates to hardware tracing tooling for ARM and Intel CPUs,
- ... and lots of other changes and cleanups - see the shortlog and
Git log for details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (322 commits)
kprobes: Prohibit probing on BUG() and WARN() address
perf/x86: Make more stuff static
x86, perf: Fix the dependency of the x86 insn decoder selftest
objtool: Ignore intentional differences for the x86 insn decoder
objtool: Update sync-check.sh from perf's check-headers.sh
perf build: Ignore intentional differences for the x86 insn decoder
perf intel-pt: Use shared x86 insn decoder
perf intel-pt: Remove inat.c from build dependency list
perf: Update .gitignore file
objtool: Move x86 insn decoder to a common location
perf metricgroup: Support multiple events for metricgroup
perf metricgroup: Scale the metric result
perf pmu: Change convert_scale from static to global
perf symbols: Move mem_info and branch_info out of symbol.h
perf auxtrace: Uninline functions that touch perf_session
perf tools: Remove needless evlist.h include directives
perf tools: Remove needless evlist.h include directives
perf tools: Remove needless thread_map.h include directives
perf tools: Remove needless thread.h include directives
perf tools: Remove needless map.h include directives
...
Pull locking updates from Ingo Molnar:
- improve rwsem scalability
- add uninitialized rwsem debugging check
- reduce lockdep's stacktrace memory usage and add diagnostics
- misc cleanups, code consolidation and constification
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
mutex: Fix up mutex_waiter usage
locking/mutex: Use mutex flags macro instead of hard code
locking/mutex: Make __mutex_owner static to mutex.c
locking/qspinlock,x86: Clarify virt_spin_lock_key
locking/rwsem: Check for operations on an uninitialized rwsem
locking/rwsem: Make handoff writer optimistically spin on owner
locking/lockdep: Report more stack trace statistics
locking/lockdep: Reduce space occupied by stack traces
stacktrace: Constify 'entries' arguments
locking/lockdep: Make it clear that what lock_class::key points at is not modified
Pull RCU updates from Ingo Molnar:
"This cycle's RCU changes were:
- A few more RCU flavor consolidation cleanups.
- Updates to RCU's list-traversal macros improving lockdep usability.
- Forward-progress improvements for no-CBs CPUs: Avoid ignoring
incoming callbacks during grace-period waits.
- Forward-progress improvements for no-CBs CPUs: Use ->cblist
structure to take advantage of others' grace periods.
- Also added a small commit that avoids needlessly inflicting
scheduler-clock ticks on callback-offloaded CPUs.
- Forward-progress improvements for no-CBs CPUs: Reduce contention on
->nocb_lock guarding ->cblist.
- Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
list to further reduce contention on ->nocb_lock guarding ->cblist.
- Miscellaneous fixes.
- Torture-test updates.
- minor LKMM updates"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (86 commits)
MAINTAINERS: Update from paulmck@linux.ibm.com to paulmck@kernel.org
rcu: Don't include <linux/ktime.h> in rcutiny.h
rcu: Allow rcu_do_batch() to dynamically adjust batch sizes
rcu/nocb: Don't wake no-CBs GP kthread if timer posted under overload
rcu/nocb: Reduce __call_rcu_nocb_wake() leaf rcu_node ->lock contention
rcu/nocb: Reduce nocb_cb_wait() leaf rcu_node ->lock contention
rcu/nocb: Advance CBs after merge in rcutree_migrate_callbacks()
rcu/nocb: Avoid synchronous wakeup in __call_rcu_nocb_wake()
rcu/nocb: Print no-CBs diagnostics when rcutorture writer unduly delayed
rcu/nocb: EXP Check use and usefulness of ->nocb_lock_contended
rcu/nocb: Add bypass callback queueing
rcu/nocb: Atomic ->len field in rcu_segcblist structure
rcu/nocb: Unconditionally advance and wake for excessive CBs
rcu/nocb: Reduce ->nocb_lock contention with separate ->nocb_gp_lock
rcu/nocb: Reduce contention at no-CBs invocation-done time
rcu/nocb: Reduce contention at no-CBs registry-time CB advancement
rcu/nocb: Round down for number of no-CBs grace-period kthreads
rcu/nocb: Avoid ->nocb_lock capture by corresponding CPU
rcu/nocb: Avoid needless wakeups of no-CBs grace-period kthread
rcu/nocb: Make __call_rcu_nocb_wake() safe for many callbacks
...
Pull parisc updates from Helge Deller:
- Make the powerpc implementation to read elf files available as a
public kexec interface so it can be re-used on other architectures
(Sven)
- Implement kexec on parisc (Sven)
- Add kprobes on ftrace on parisc (Sven)
- Fix kernel crash with HSC-PCI cards based on card-mode Dino
- Add assembly implementations for memset, strlen, strcpy, strncpy and
strcat
- Some cleanups, documentation updates, warning fixes, ...
* 'parisc-5.4-1' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux: (25 commits)
parisc: Have git ignore generated real2.S and firmware.c
parisc: Disable HP HSC-PCI Cards to prevent kernel crash
parisc: add support for kexec_file_load() syscall
parisc: wire up kexec_file_load syscall
parisc: add kexec syscall support
parisc: add __pdc_cpu_rendezvous()
kprobes/parisc: remove arch_kprobe_on_func_entry()
kexec_elf: support 32 bit ELF files
kexec_elf: remove unused variable in kexec_elf_load()
kexec_elf: remove Elf_Rel macro
kexec_elf: remove PURGATORY_STACK_SIZE
kexec_elf: remove parsing of section headers
kexec_elf: change order of elf_*_to_cpu() functions
kexec: add KEXEC_ELF
parisc: Save some bytes in dino driver
parisc: Drop comments which are already in pci.h
parisc: Convert eisa_enumerator to use pr_cont()
parisc: Avoid warning when loading hppb driver
parisc: speed up flush_tlb_all_local with qemu
parisc: Add ALTERNATIVE_CODE() and ALT_COND_RUN_ON_QEMU
...
-----BEGIN PGP SIGNATURE-----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=L5e+
-----END PGP SIGNATURE-----
Merge tag 'please-pull-ia64_for_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux
Pull ia64 updates from Tony Luck:
"The big change here is removal of support for SGI Altix"
* tag 'please-pull-ia64_for_5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/aegl/linux: (33 commits)
genirq: remove the is_affinity_mask_valid hook
ia64: remove CONFIG_SWIOTLB ifdefs
ia64: remove support for machvecs
ia64: move the screen_info setup to common code
ia64: move the ROOT_DEV setup to common code
ia64: rework iommu probing
ia64: remove the unused sn_coherency_id symbol
ia64: remove the SGI UV simulator support
ia64: remove the zx1 swiotlb machvec
ia64: remove CONFIG_ACPI ifdefs
ia64: remove CONFIG_PCI ifdefs
ia64: remove the hpsim platform
ia64: remove now unused machvec indirections
ia64: remove support for the SGI SN2 platform
drivers: remove the SGI SN2 IOC4 base support
drivers: remove the SGI SN2 IOC3 base support
qla2xxx: remove SGI SN2 support
qla1280: remove SGI SN2 support
misc/sgi-xp: remove SGI SN2 support
char/mspec: remove SGI SN2 support
...
- 52-bit virtual addressing in the kernel
- New ABI to allow tagged user pointers to be dereferenced by syscalls
- Early RNG seeding by the bootloader
- Improve robustness of SMP boot
- Fix TLB invalidation in light of recent architectural clarifications
- Support for i.MX8 DDR PMU
- Remove direct LSE instruction patching in favour of static keys
- Function error injection using kprobes
- Support for the PPTT "thread" flag introduced by ACPI 6.3
- Move PSCI idle code into proper cpuidle driver
- Relaxation of implicit I/O memory barriers
- Build with RELR relocations when toolchain supports them
- Numerous cleanups and non-critical fixes
-----BEGIN PGP SIGNATURE-----
iQFEBAABCgAuFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl1yYREQHHdpbGxAa2Vy
bmVsLm9yZwAKCRC3rHDchMFjNAM3CAChqDFQkryXoHwdeEcaukMRVNxtxOi4pM4g
5xqkb7PoqRJssIblsuhaXjrSD97yWCgaqCmFe6rKoes++lP4bFcTe22KXPPyPBED
A+tK4nTuKKcZfVbEanUjI+ihXaHJmKZ/kwAxWsEBYZ4WCOe3voCiJVNO2fHxqg1M
8TskZ2BoayTbWMXih0eJg2MCy/xApBq4b3nZG4bKI7Z9UpXiKN1NYtDh98ZEBK4V
d/oNoHsJ2ZvIQsztoBJMsvr09DTCazCijWZiECadm6l41WEPFizngrACiSJLLtYo
0qu4qxgg9zgFlvBCRQmIYSggTuv35RgXSfcOwChmW5DUjHG+f9GK
=Ru4B
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Will Deacon:
"Although there isn't tonnes of code in terms of line count, there are
a fair few headline features which I've noted both in the tag and also
in the merge commits when I pulled everything together.
The part I'm most pleased with is that we had 35 contributors this
time around, which feels like a big jump from the usual small group of
core arm64 arch developers. Hopefully they all enjoyed it so much that
they'll continue to contribute, but we'll see.
It's probably worth highlighting that we've pulled in a branch from
the risc-v folks which moves our CPU topology code out to where it can
be shared with others.
Summary:
- 52-bit virtual addressing in the kernel
- New ABI to allow tagged user pointers to be dereferenced by
syscalls
- Early RNG seeding by the bootloader
- Improve robustness of SMP boot
- Fix TLB invalidation in light of recent architectural
clarifications
- Support for i.MX8 DDR PMU
- Remove direct LSE instruction patching in favour of static keys
- Function error injection using kprobes
- Support for the PPTT "thread" flag introduced by ACPI 6.3
- Move PSCI idle code into proper cpuidle driver
- Relaxation of implicit I/O memory barriers
- Build with RELR relocations when toolchain supports them
- Numerous cleanups and non-critical fixes"
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (114 commits)
arm64: remove __iounmap
arm64: atomics: Use K constraint when toolchain appears to support it
arm64: atomics: Undefine internal macros after use
arm64: lse: Make ARM64_LSE_ATOMICS depend on JUMP_LABEL
arm64: asm: Kill 'asm/atomic_arch.h'
arm64: lse: Remove unused 'alt_lse' assembly macro
arm64: atomics: Remove atomic_ll_sc compilation unit
arm64: avoid using hard-coded registers for LSE atomics
arm64: atomics: avoid out-of-line ll/sc atomics
arm64: Use correct ll/sc atomic constraints
jump_label: Don't warn on __exit jump entries
docs/perf: Add documentation for the i.MX8 DDR PMU
perf/imx_ddr: Add support for AXI ID filtering
arm64: kpti: ensure patched kernel text is fetched from PoU
arm64: fix fixmap copy for 16K pages and 48-bit VA
perf/smmuv3: Validate groups for global filtering
perf/smmuv3: Validate group size
arm64: Relax Documentation/arm64/tagged-pointers.rst
arm64: kvm: Replace hardcoded '1' with SYS_PAR_EL1_F
arm64: mm: Ignore spurious translation faults taken from the kernel
...
Including:
- Batched unmap support for the IOMMU-API
- Support for unlocked command queueing in the ARM-SMMU driver
- Rework the ATS support in the ARM-SMMU driver
- More refactoring in the ARM-SMMU driver to support hardware
implemention specific quirks and errata
- Bounce buffering DMA-API implementatation in the Intel VT-d driver
for untrusted devices (like Thunderbolt devices)
- Fixes for runtime PM support in the OMAP iommu driver
- MT8183 IOMMU support in the Mediatek IOMMU driver
- Rework of the way the IOMMU core sets the default domain type for
groups. Changing the default domain type on x86 does not require two
kernel parameters anymore.
- More smaller fixes and cleanups
-----BEGIN PGP SIGNATURE-----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=UF08
-----END PGP SIGNATURE-----
Merge tag 'iommu-updates-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
- batched unmap support for the IOMMU-API
- support for unlocked command queueing in the ARM-SMMU driver
- rework the ATS support in the ARM-SMMU driver
- more refactoring in the ARM-SMMU driver to support hardware
implemention specific quirks and errata
- bounce buffering DMA-API implementatation in the Intel VT-d driver
for untrusted devices (like Thunderbolt devices)
- fixes for runtime PM support in the OMAP iommu driver
- MT8183 IOMMU support in the Mediatek IOMMU driver
- rework of the way the IOMMU core sets the default domain type for
groups. Changing the default domain type on x86 does not require two
kernel parameters anymore.
- more smaller fixes and cleanups
* tag 'iommu-updates-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (113 commits)
iommu/vt-d: Declare Broadwell igfx dmar support snafu
iommu/vt-d: Add Scalable Mode fault information
iommu/vt-d: Use bounce buffer for untrusted devices
iommu/vt-d: Add trace events for device dma map/unmap
iommu/vt-d: Don't switch off swiotlb if bounce page is used
iommu/vt-d: Check whether device requires bounce buffer
swiotlb: Split size parameter to map/unmap APIs
iommu/omap: Mark pm functions __maybe_unused
iommu/ipmmu-vmsa: Disable cache snoop transactions on R-Car Gen3
iommu/ipmmu-vmsa: Move IMTTBCR_SL0_TWOBIT_* to restore sort order
iommu: Don't use sme_active() in generic code
iommu/arm-smmu-v3: Fix build error without CONFIG_PCI_ATS
iommu/qcom: Use struct_size() helper
iommu: Remove wrong default domain comments
iommu/dma: Fix for dereferencing before null checking
iommu/mediatek: Clean up struct mtk_smi_iommu
memory: mtk-smi: Get rid of need_larbid
iommu/mediatek: Fix VLD_PA_RNG register backup when suspend
memory: mtk-smi: Add bus_sel for mt8183
memory: mtk-smi: Invoke pm runtime_callback to enable clocks
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXXe8mQAKCRCRxhvAZXjc
ou7oAQCszihkNfpjORSSSOqenMDrxxDW++A7TIOLuq7UyZQl8QD+LM1wvT/xypfJ
ORD9XX8+Wrv07AQn85fZBEFXGrnengk=
=o+VL
-----END PGP SIGNATURE-----
Merge tag 'core-process-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd/waitid updates from Christian Brauner:
"This contains two features and various tests.
First, it adds support for waiting on process through pidfds by adding
the P_PIDFD type to the waitid() syscall. This completes the basic
functionality of the pidfd api (cf. [1]). In the meantime we also have
a new adition to the userspace projects that make use of the pidfd
api. The qt project was nice enough to send a mail pointing out that
they have a pr up to switch to the pidfd api (cf. [2]).
Second, this tag contains an extension to the waitid() syscall to make
it possible to wait on the current process group in a race free manner
(even though the actual problem is very unlikely) by specifing 0
together with the P_PGID type. This extension traces back to a
discussion on the glibc development mailing list.
There are also a range of tests for the features above. Additionally,
the test-suite which detected the pidfd-polling race we fixed in [3]
is included in this tag"
[1] https://lwn.net/Articles/794707/
[2] https://codereview.qt-project.org/c/qt/qtbase/+/108456
[3] commit b191d6491b ("pidfd: fix a poll race when setting exit_state")
* tag 'core-process-v5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
waitid: Add support for waiting for the current process group
tests: add pidfd poll tests
tests: move common definitions and functions into pidfd.h
pidfd: add pidfd_wait tests
pidfd: add P_PIDFD to waitid()
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-09-16
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Now that initial BPF backend for gcc has been merged upstream, enable
BPF kselftest suite for bpf-gcc. Also fix a BE issue with access to
bpf_sysctl.file_pos, from Ilya.
2) Follow-up fix for link-vmlinux.sh to remove bash-specific extensions
related to recent work on exposing BTF info through sysfs, from Andrii.
3) AF_XDP zero copy fixes for i40e and ixgbe driver which caused umem
headroom to be added twice, from Ciara.
4) Refactoring work to convert sock opt tests into test_progs framework
in BPF kselftests, from Stanislav.
5) Fix a general protection fault in dev_map_hash_update_elem(), from Toke.
6) Cleanup to use BPF_PROG_RUN() macro in KCM, from Sami.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
"ctx:file_pos sysctl:read write ok" fails on s390 with "Read value !=
nux". This is because verifier rewrites a complete 32-bit
bpf_sysctl.file_pos update to a partial update of the first 32 bits of
64-bit *bpf_sysctl_kern.ppos, which is not correct on big-endian
systems.
Fix by using an offset on big-endian systems.
Ditto for bpf_sysctl.file_pos reads. Currently the test does not detect
a problem there, since it expects to see 0, which it gets with high
probability in error cases, so change it to seek to offset 3 and expect
3 in bpf_sysctl.file_pos.
Fixes: e1550bfe0d ("bpf: Add file_pos field to bpf_sysctl ctx")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20190816105300.49035-1-iii@linux.ibm.com/
syzbot found a crash in dev_map_hash_update_elem(), when replacing an
element with a new one. Jesper correctly identified the cause of the crash
as a race condition between the initial lookup in the map (which is done
before taking the lock), and the removal of the old element.
Rather than just add a second lookup into the hashmap after taking the
lock, fix this by reworking the function logic to take the lock before the
initial lookup.
Fixes: 6f9d451ab1 ("xdp: Add devmap_hash map type for looking up devices by hashed index")
Reported-and-tested-by: syzbot+4e7a85b1432052e8d6f8@syzkaller.appspotmail.com
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
We do need to call the constructors for *modules*, and
at least for KASAN in the future, we must call even the
kernel constructors only later when the kernel has been
initialized.
Instead of relying on libc to call them, emit an empty
section for libc and let the kernel's CONSTRUCTORS code
do the rest of the job.
Tested that it indeed doesn't work in modules, and does
work after the fixes in both, with a few functions with
__attribute__((constructor)) in both dynamic and static
builds.
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
Signed-off-by: Richard Weinberger <richard@nod.at>
Pull networking fixes from David Miller:
1) Don't corrupt xfrm_interface parms before validation, from Nicolas
Dichtel.
2) Revert use of usb-wakeup in btusb, from Mario Limonciello.
3) Block ipv6 packets in bridge netfilter if ipv6 is disabled, from
Leonardo Bras.
4) IPS_OFFLOAD not honored in ctnetlink, from Pablo Neira Ayuso.
5) Missing ULP check in sock_map, from John Fastabend.
6) Fix receive statistic handling in forcedeth, from Zhu Yanjun.
7) Fix length of SKB allocated in 6pack driver, from Christophe
JAILLET.
8) ip6_route_info_create() returns an error pointer, not NULL. From
Maciej Żenczykowski.
9) Only add RDS sock to the hashes after rs_transport is set, from
Ka-Cheong Poon.
10) Don't double clean TX descriptors in ixgbe, from Ilya Maximets.
11) Presence of transmit IPSEC offload in an SKB is not tested for
correctly in ixgbe and ixgbevf. From Steffen Klassert and Jeff
Kirsher.
12) Need rcu_barrier() when register_netdevice() takes one of the
notifier based failure paths, from Subash Abhinov Kasiviswanathan.
13) Fix leak in sctp_do_bind(), from Mao Wenan.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (72 commits)
cdc_ether: fix rndis support for Mediatek based smartphones
sctp: destroy bucket if failed to bind addr
sctp: remove redundant assignment when call sctp_get_port_local
sctp: change return type of sctp_get_port_local
ixgbevf: Fix secpath usage for IPsec Tx offload
sctp: Fix the link time qualifier of 'sctp_ctrlsock_exit()'
ixgbe: Fix secpath usage for IPsec TX offload.
net: qrtr: fix memort leak in qrtr_tun_write_iter
net: Fix null de-reference of device refcount
ipv6: Fix the link time qualifier of 'ping_v6_proc_exit_net()'
tun: fix use-after-free when register netdev failed
tcp: fix tcp_ecn_withdraw_cwr() to clear TCP_ECN_QUEUE_CWR
ixgbe: fix double clean of Tx descriptors with xdp
ixgbe: Prevent u8 wrapping of ITR value to something less than 10us
mlx4: fix spelling mistake "veify" -> "verify"
net: hns3: fix spelling mistake "undeflow" -> "underflow"
net: lmc: fix spelling mistake "runnin" -> "running"
NFC: st95hf: fix spelling mistake "receieve" -> "receive"
net/rds: An rds_sock is added too early to the hash table
mac80211: Do not send Layer 2 Update frame before authorization
...
With the removal of the ENODATA case from padata_get_next, the cpu_index
field is no longer useful, so it can go away.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Padata binds the parallel part of a job to a single CPU and round-robins
over all CPUs in the system for each successive job. Though the serial
parts rely on per-CPU queues for correct ordering, they're not necessary
for parallel work, and it improves performance to run the job locally on
NUMA machines and let the scheduler pick the CPU within a node on a busy
system.
So, make the parallel workqueue unbound.
Update the parallel workqueue's cpumask when the instance's parallel
cpumask changes.
Now that parallel jobs no longer run on max_active=1 workqueues, two or
more parallel works that hash to the same CPU may run simultaneously,
finish out of order, and so be serialized out of order. Prevent this by
keeping the works sorted on the reorder list by sequence number and
checking that in the reordering logic.
padata_get_next becomes padata_find_next so it can be reused for the end
of padata_reorder, where it's used to avoid uselessly queueing work when
the next job by sequence number isn't finished yet but a later job that
hashed to the same CPU has.
The ENODATA case in padata_find_next no longer makes sense because
parallel jobs aren't bound to specific CPUs. The EINPROGRESS case takes
care of the scenario where a parallel job is potentially running on the
same CPU as padata_find_next, and with only one error code left, just
use NULL instead.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
padata currently uses one per-CPU workqueue per instance for all work.
Prepare for running parallel jobs on an unbound workqueue by introducing
dedicated workqueues for parallel and serial work.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
With pcrypt's cpumask no longer used, take the CPU hotplug lock inside
padata_alloc_possible.
Useful later in the series for avoiding nested acquisition of the CPU
hotplug lock in padata when padata_alloc_possible is allocating an
unbound workqueue.
Without this patch, this nested acquisition would happen later in the
series:
pcrypt_init_padata
get_online_cpus
alloc_padata_possible
alloc_padata
alloc_workqueue(WQ_UNBOUND) // later in the series
alloc_and_link_pwqs
apply_wqattrs_lock
get_online_cpus // recursive rwsem acquisition
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
padata_do_parallel currently returns -EINVAL if the callback CPU isn't
in the callback cpumask.
pcrypt tries to prevent this situation by keeping its own callback
cpumask in sync with padata's and checks that the callback CPU it passes
to padata is valid. Make padata handle this instead.
padata_do_parallel now takes a pointer to the callback CPU and updates
it for the caller if an alternate CPU is used. Overall behavior in
terms of which callback CPUs are chosen stays the same.
Prepares for removal of the padata cpumask notifier in pcrypt, which
will fix a lockdep complaint about nested acquisition of the CPU hotplug
lock later in the series.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Change the calling convention for apply_workqueue_attrs to require CPU
hotplug read exclusion.
Avoids lockdep complaints about nested calls to get_online_cpus in a
future patch where padata calls apply_workqueue_attrs when changing
other CPU-hotplug-sensitive data structures with the CPU read lock
already held.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
padata will use these these interfaces in a later patch, so unconfine them.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Tejun Heo <tj@kernel.org>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Move workqueue allocation inside of padata to prepare for further
changes to how padata uses workqueues.
Guarantees the workqueue is created with max_active=1, which padata
relies on to work correctly. No functional change.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Acked-by: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tejun Heo <tj@kernel.org>
Cc: linux-crypto@vger.kernel.org
Cc: linux-doc@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
EAS computes the energy impact of migrating a waking task when deciding
on which CPU it should run. However, the current approach is known to
have a high algorithmic complexity, which can result in prohibitively
high wake-up latencies on systems with complex energy models, such as
systems with per-CPU DVFS. On such systems, the algorithm complexity is
in O(n^2) (ignoring the cost of searching for performance states in the
EM) with 'n' the number of CPUs.
To address this, re-factor the EAS wake-up path to compute the energy
'delta' (with and without the task) on a per-performance domain basis,
rather than system-wide, which brings the complexity down to O(n).
No functional changes intended.
Test results
~~~~~~~~~~~~
* Setup: Tested on a Google Pixel 3, with a Snapdragon 845 (4+4 CPUs,
A55/A75). Base kernel is 5.3-rc5 + Pixel3 specific patches. Android
userspace, no graphics.
* Test case: Run a periodic rt-app task, with 16ms period, ramping down
from 70% to 10%, in 5% steps of 500 ms each (json avail. at [1]).
Frequencies of all CPUs are pinned to max (using scaling_min_freq
CPUFreq sysfs entries) to reduce variability. The time to run
select_task_rq_fair() is measured using the function profiler
(/sys/kernel/debug/tracing/trace_stat/function*). See the test script
for more details [2].
Test 1:
I hacked the DT to 'fake' per-CPU DVFS. That is, we end up with one
CPUFreq policy per CPU (8 policies in total). Since all frequencies are
pinned to max for the test, this should have no impact on the actual
frequency selection, but it does in the EAS calculation.
+---------------------------+----------------------------------+
| Without patch | With patch |
+-----+-----+----------+----------+-----+-----------------+----------+
| CPU | Hit | Avg (us) | s^2 (us) | Hit | Avg (us) | s^2 (us) |
|-----+-----+----------+----------+-----+-----------------+----------+
| 0 | 274 | 38.303 | 1750.239 | 401 | 14.126 (-63.1%) | 146.625 |
| 1 | 197 | 49.529 | 1695.852 | 314 | 16.135 (-67.4%) | 167.525 |
| 2 | 142 | 34.296 | 1758.665 | 302 | 14.133 (-58.8%) | 130.071 |
| 3 | 172 | 31.734 | 1490.975 | 641 | 14.637 (-53.9%) | 139.189 |
| 4 | 316 | 7.834 | 178.217 | 425 | 5.413 (-30.9%) | 20.803 |
| 5 | 447 | 8.424 | 144.638 | 556 | 5.929 (-29.6%) | 27.301 |
| 6 | 581 | 14.886 | 346.793 | 456 | 5.711 (-61.6%) | 23.124 |
| 7 | 456 | 10.005 | 211.187 | 997 | 4.708 (-52.9%) | 21.144 |
+-----+-----+----------+----------+-----+-----------------+----------+
* Hit, Avg and s^2 are as reported by the function profiler
Test 2:
I also ran the same test with a normal DT, with 2 CPUFreq policies, to
see if this causes regressions in the most common case.
+---------------------------+----------------------------------+
| Without patch | With patch |
+-----+-----+----------+----------+-----+-----------------+----------+
| CPU | Hit | Avg (us) | s^2 (us) | Hit | Avg (us) | s^2 (us) |
|-----+-----+----------+----------+-----+-----------------+----------+
| 0 | 345 | 22.184 | 215.321 | 580 | 18.635 (-16.0%) | 146.892 |
| 1 | 358 | 18.597 | 200.596 | 438 | 12.934 (-30.5%) | 104.604 |
| 2 | 359 | 25.566 | 200.217 | 397 | 10.826 (-57.7%) | 74.021 |
| 3 | 362 | 16.881 | 200.291 | 718 | 11.455 (-32.1%) | 102.280 |
| 4 | 457 | 3.822 | 9.895 | 757 | 4.616 (+20.8%) | 13.369 |
| 5 | 344 | 4.301 | 7.121 | 594 | 5.320 (+23.7%) | 18.798 |
| 6 | 472 | 4.326 | 7.849 | 464 | 5.648 (+30.6%) | 22.022 |
| 7 | 331 | 4.630 | 13.937 | 408 | 5.299 (+14.4%) | 18.273 |
+-----+-----+----------+----------+-----+-----------------+----------+
* Hit, Avg and s^2 are as reported by the function profiler
In addition to these two tests, I also ran 50 iterations of the Lisa
EAS functional test suite [3] with this patch applied on Arm Juno r0,
Arm Juno r2, Arm TC2 and Hikey960, and could not see any regressions
(all EAS functional tests are passing).
[1] https://paste.debian.net/1100055/
[2] https://paste.debian.net/1100057/
[3] https://github.com/ARM-software/lisa/blob/master/lisa/tests/scheduler/eas_behaviour.py
Signed-off-by: Quentin Perret <quentin.perret@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: juri.lelli@redhat.com
Cc: morten.rasmussen@arm.com
Cc: qais.yousef@arm.com
Cc: qperret@qperret.net
Cc: rjw@rjwysocki.net
Cc: tkjos@google.com
Cc: valentin.schneider@arm.com
Cc: vincent.guittot@linaro.org
Link: https://lkml.kernel.org/r/20190912094404.13802-1-qperret@qperret.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a new child cgroup is created in the frozen cgroup hierarchy
(one or more of ancestor cgroups is frozen), the CGRP_FREEZE cgroup
flag should be set. Otherwise if a process will be attached to the
child cgroup, it won't become frozen.
The problem can be reproduced with the test_cgfreezer_mkdir test.
This is the output before this patch:
~/test_freezer
ok 1 test_cgfreezer_simple
ok 2 test_cgfreezer_tree
ok 3 test_cgfreezer_forkbomb
Cgroup /sys/fs/cgroup/cg_test_mkdir_A/cg_test_mkdir_B isn't frozen
not ok 4 test_cgfreezer_mkdir
ok 5 test_cgfreezer_rmdir
ok 6 test_cgfreezer_migrate
ok 7 test_cgfreezer_ptrace
ok 8 test_cgfreezer_stopped
ok 9 test_cgfreezer_ptraced
ok 10 test_cgfreezer_vfork
And with this patch:
~/test_freezer
ok 1 test_cgfreezer_simple
ok 2 test_cgfreezer_tree
ok 3 test_cgfreezer_forkbomb
ok 4 test_cgfreezer_mkdir
ok 5 test_cgfreezer_rmdir
ok 6 test_cgfreezer_migrate
ok 7 test_cgfreezer_ptrace
ok 8 test_cgfreezer_stopped
ok 9 test_cgfreezer_ptraced
ok 10 test_cgfreezer_vfork
Reported-by: Mark Crossen <mcrossen@fb.com>
Signed-off-by: Roman Gushchin <guro@fb.com>
Fixes: 76f969e894 ("cgroup: cgroup v2 freezer")
Cc: Tejun Heo <tj@kernel.org>
Cc: stable@vger.kernel.org # v5.2+
Signed-off-by: Tejun Heo <tj@kernel.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXXpIKgAKCRCRxhvAZXjc
om8yAQCIPJp2HWNsJRPRl9KVKRmR6MxItG1Hpj0MvgwzLEjufwD/SF9VAPgl2AmD
oaAXrOYH4yhr9aaFlVuMpe2aWAZdxgU=
=Tjvf
-----END PGP SIGNATURE-----
Merge tag 'for-linus-20190912' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux
Pull clone3 fix from Christian Brauner:
"This is a last-minute bugfix for clone3() that should go in before we
release 5.3 with clone3().
clone3() did not verify that the exit_signal argument was set to a
valid signal. This can be used to cause a crash by specifying a signal
greater than NSIG. e.g. -1.
The commit from Eugene adds a check to copy_clone_args_from_user() to
verify that the exit signal is limited by CSIGNAL as with legacy
clone() and that the signal is valid. With this we don't get the
legacy clone behavior were an invalid signal could be handed down and
would only be detected and then ignored in do_notify_parent(). Users
of clone3() will now get a proper error right when they pass an
invalid exit signal. Note, that this is not a change in user-visible
behavior since no kernel with clone3() has been released yet"
* tag 'for-linus-20190912' of gitolite.kernel.org:pub/scm/linux/kernel/git/brauner/linux:
fork: block invalid exit signals with clone3()
Previously, higher 32 bits of exit_signal fields were lost when copied
to the kernel args structure (that uses int as a type for the respective
field). Moreover, as Oleg has noted, exit_signal is used unchecked, so
it has to be checked for sanity before use; for the legacy syscalls,
applying CSIGNAL mask guarantees that it is at least non-negative;
however, there's no such thing is done in clone3() code path, and that
can break at least thread_group_leader.
This commit adds a check to copy_clone_args_from_user() to verify that
the exit signal is limited by CSIGNAL as with legacy clone() and that
the signal is valid. With this we don't get the legacy clone behavior
were an invalid signal could be handed down and would only be detected
and ignored in do_notify_parent(). Users of clone3() will now get a
proper error when they pass an invalid exit signal. Note, that this is
not user-visible behavior since no kernel with clone3() has been
released yet.
The following program will cause a splat on a non-fixed clone3() version
and will fail correctly on a fixed version:
#define _GNU_SOURCE
#include <linux/sched.h>
#include <linux/types.h>
#include <sched.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/syscall.h>
#include <sys/wait.h>
#include <unistd.h>
int main(int argc, char *argv[])
{
pid_t pid = -1;
struct clone_args args = {0};
args.exit_signal = -1;
pid = syscall(__NR_clone3, &args, sizeof(struct clone_args));
if (pid < 0)
exit(EXIT_FAILURE);
if (pid == 0)
exit(EXIT_SUCCESS);
wait(NULL);
exit(EXIT_SUCCESS);
}
Fixes: 7f192e3cd3 ("fork: add clone3")
Reported-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Oleg Nesterov <oleg@redhat.com>
Suggested-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Eugene Syromiatnikov <esyr@redhat.com>
Link: https://lore.kernel.org/r/4b38fa4ce420b119a4c6345f42fe3cec2de9b0b5.1568223594.git.esyr@redhat.com
[christian.brauner@ubuntu.com: simplify check and rework commit message]
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Pull perf fix from Ingo Molnar:
"Fix an initialization bug in the hw-breakpoints, which triggered on
the ARM platform"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/hw_breakpoint: Fix arch_hw_breakpoint use-before-initialization
Pull irq fix from Ingo Molnar:
"Fix a race in the IRQ resend mechanism, which can result in a NULL
dereference crash"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Prevent NULL pointer dereference in resend_irqs()
You can pass opaque pointers directly.
I also renamed 'va' and 'vb' into more meaningful arguments.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Commit 8651ec01da ("module: add support for symbol namespaces.")
broke linking for arm64 defconfig:
| lib/crypto/arc4.o: In function `__ksymtab_arc4_setkey':
| arc4.c:(___ksymtab+arc4_setkey+0x8): undefined reference to `no symbol'
| lib/crypto/arc4.o: In function `__ksymtab_arc4_crypt':
| arc4.c:(___ksymtab+arc4_crypt+0x8): undefined reference to `no symbol'
This is because the dummy initialisation of the 'namespace_offset' field
in 'struct kernel_symbol' when using EXPORT_SYMBOL on architectures with
support for PREL32 locations uses an offset from an absolute address (0)
in an effort to trick 'offset_to_pointer' into behaving as a NOP,
allowing non-namespaced symbols to be treated in the same way as those
belonging to a namespace.
Unfortunately, place-relative relocations require a symbol reference
rather than an absolute value and, although x86 appears to get away with
this due to placing the kernel text at the top of the address space, it
almost certainly results in a runtime failure if the kernel is relocated
dynamically as a result of KASLR.
Rework 'namespace_offset' so that a value of 0, which cannot occur for a
valid namespaced symbol, indicates that the corresponding symbol does
not belong to a namespace.
Cc: Matthias Maennich <maennich@google.com>
Cc: Jessica Yu <jeyu@kernel.org>
Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Fixes: 8651ec01da ("module: add support for symbol namespaces.")
Reported-by: kbuild test robot <lkp@intel.com>
Tested-by: Matthias Maennich <maennich@google.com>
Tested-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Reviewed-by: Matthias Maennich <maennich@google.com>
Acked-by: Ard Biesheuvel <ard.biesheuvel@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
This splits the size parameter to swiotlb_tbl_map_single() and
swiotlb_tbl_unmap_single() into an alloc_size and a mapping_size
parameter, where the latter one is rounded up to the iommu page
size.
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Joerg Roedel <jroedel@suse.de>
It was recently discovered that the linux version of waitid is not a
superset of the other wait functions because it does not include support
for waiting for the current process group. This has two downsides:
1. An extra system call is needed to get the current process group.
2. After the current process group is received and before it is passed
to waitid a signal could arrive causing the current process group to change.
Inherent race-conditions as these make it impossible for userspace to
emulate this functionaly and thus violate async-signal safety
requirements for waitpid.
Arguments can be made for using a different choice of idtype and id
for this case but the BSDs already use this P_PGID and 0 to indicate
waiting for the current process's process group. So be nice to user
space programmers and don't introduce an unnecessary incompatibility.
Some people have noted that the posix description is that
waitpid will wait for the current process group, and that in
the presence of pthreads that process group can change. To get
clarity on this issue I looked at XNU, FreeBSD, and Luminos. All of
those flavors of unix waited for the current process group at the
time of call and as written could not adapt to the process group
changing after the call.
At one point Linux did adapt to the current process group changing but
that stopped in 161550d74c ("pid: sys_wait... fixes"). It has been
over 11 years since Linux has that behavior, no programs that fail
with the change in behavior have been reported, and I could not
find any other unix that does this. So I think it is safe to clarify
the definition of current process group, to current process group
at the time of the wait function.
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Palmer Dabbelt <palmer@sifive.com>
Cc: Rich Felker <dalias@libc.org>
Cc: Alistair Francis <alistair23@gmail.com>
Cc: Zong Li <zongbox@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Cc: GNU C Library <libc-alpha@sourceware.org>
Link: https://lore.kernel.org/r/20190814154400.6371-2-christian.brauner@ubuntu.com
The recent consolidation of the three permission checks introduced a subtle
regression. For timer_create() with a process wide timer it returns the
current task if the lookup through the PID which is encoded into the
clockid results in returning current.
That's broken because it does not validate whether the current task is the
group leader.
That was caused by the two different variants of permission checks:
- posix_cpu_timer_get() allowed access to the process wide clock when the
looked up task is current. That's not an issue because the process wide
clock is in the shared sighand.
- posix_cpu_timer_create() made sure that the looked up task is the group
leader.
Restore the previous state.
Note, that these permission checks are more than questionable, but that's
subject to follow up changes.
Fixes: 6ae40e3fdc ("posix-cpu-timers: Provide task validation functions")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1909052314110.1902@nanos.tec.linutronix.de
If MODULE_ALLOW_MISSING_NAMESPACE_IMPORTS is enabled (default=n), the
requirement for modules to import all namespaces that are used by
the module is relaxed.
Enabling this option effectively allows (invalid) modules to be loaded
while only a warning is emitted.
Disabling this option keeps the enforcement at module loading time and
loading is denied if the module's imports are not satisfactory.
Reviewed-by: Martijn Coenen <maco@android.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
The EXPORT_SYMBOL_NS() and EXPORT_SYMBOL_NS_GPL() macros can be used to
export a symbol to a specific namespace. There are no _GPL_FUTURE and
_UNUSED variants because these are currently unused, and I'm not sure
they are necessary.
I didn't add EXPORT_SYMBOL_NS() for ASM exports; this patch sets the
namespace of ASM exports to NULL by default. In case of relative
references, it will be relocatable to NULL. If there's a need, this
should be pretty easy to add.
A module that wants to use a symbol exported to a namespace must add a
MODULE_IMPORT_NS() statement to their module code; otherwise, modpost
will complain when building the module, and the kernel module loader
will emit an error and fail when loading the module.
MODULE_IMPORT_NS() adds a modinfo tag 'import_ns' to the module. That
tag can be observed by the modinfo command, modpost and kernel/module.c
at the time of loading the module.
The ELF symbols are renamed to include the namespace with an asm label;
for example, symbol 'usb_stor_suspend' in namespace USB_STORAGE becomes
'usb_stor_suspend.USB_STORAGE'. This allows modpost to do namespace
checking, without having to go through all the effort of parsing ELF and
relocation records just to get to the struct kernel_symbols.
On x86_64 I saw no difference in binary size (compression), but at
runtime this will require a word of memory per export to hold the
namespace. An alternative could be to store namespaced symbols in their
own section and use a separate 'struct namespaced_kernel_symbol' for
that section, at the cost of making the module loader more complex.
Co-developed-by: Martijn Coenen <maco@android.com>
Signed-off-by: Martijn Coenen <maco@android.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Similar to modpost's get_next_modinfo(), introduce get_next_modinfo() in
kernel/module.c to acquire any further values associated with the same
modinfo tag name. That is useful for any tags that have multiple
occurrences (such as 'alias'), but is in particular introduced here as
part of the symbol namespaces patch series to read the (potentially)
multiple namespaces a module is importing.
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: Martijn Coenen <maco@android.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Matthias Maennich <maennich@google.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
In some special cases we must not block, but there's not a spinlock,
preempt-off, irqs-off or similar critical section already that arms the
might_sleep() debug checks. Add a non_block_start/end() pair to annotate
these.
This will be used in the oom paths of mmu-notifiers, where blocking is not
allowed to make sure there's forward progress. Quoting Michal:
"The notifier is called from quite a restricted context - oom_reaper -
which shouldn't depend on any locks or sleepable conditionals. The code
should be swift as well but we mostly do care about it to make a forward
progress. Checking for sleepable context is the best thing we could come
up with that would describe these demands at least partially."
Peter also asked whether we want to catch spinlocks on top, but Michal
said those are less of a problem because spinlocks can't have an indirect
dependency upon the page allocator and hence close the loop with the oom
reaper.
Suggested by Michal Hocko.
Link: https://lore.kernel.org/r/20190826201425.17547-4-daniel.vetter@ffwll.ch
Acked-by: Christian König <christian.koenig@amd.com> (v1)
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The powerpc version only supported 64 bit. Add some
code to switch decoding of fields during runtime so
we can kexec a 32 bit kernel from a 64 bit kernel and
vice versa.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
base was never assigned, so we can remove it.
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
It wasn't used anywhere, so lets drop it.
Reviewed-by: Christophe Leroy <christophe.leroy@c-s.fr>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Signed-off-by: Helge Deller <deller@gmx.de>
It's not used anywhere so just drop it.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
We're not using them, so we can drop the parsing.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Change the order to have a 64/32/16 order, no functional change.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Right now powerpc provides an implementation to read elf files
with the kexec_file_load() syscall. Make that available as a public
kexec interface so it can be re-used on other architectures.
Signed-off-by: Sven Schnelle <svens@stackframe.org>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Signed-off-by: Helge Deller <deller@gmx.de>
Daniel Borkmann says:
====================
The following pull-request contains BPF updates for your *net-next* tree.
The main changes are:
1) Add the ability to use unaligned chunks in the AF_XDP umem. By
relaxing where the chunks can be placed, it allows to use an
arbitrary buffer size and place whenever there is a free
address in the umem. Helps more seamless DPDK AF_XDP driver
integration. Support for i40e, ixgbe and mlx5e, from Kevin and
Maxim.
2) Addition of a wakeup flag for AF_XDP tx and fill rings so the
application can wake up the kernel for rx/tx processing which
avoids busy-spinning of the latter, useful when app and driver
is located on the same core. Support for i40e, ixgbe and mlx5e,
from Magnus and Maxim.
3) bpftool fixes for printf()-like functions so compiler can actually
enforce checks, bpftool build system improvements for custom output
directories, and addition of 'bpftool map freeze' command, from Quentin.
4) Support attaching/detaching XDP programs from 'bpftool net' command,
from Daniel.
5) Automatic xskmap cleanup when AF_XDP socket is released, and several
barrier/{read,write}_once fixes in AF_XDP code, from Björn.
6) Relicense of bpf_helpers.h/bpf_endian.h for future libbpf
inclusion as well as libbpf versioning improvements, from Andrii.
7) Several new BPF kselftests for verifier precision tracking, from Alexei.
8) Several BPF kselftest fixes wrt endianess to run on s390x, from Ilya.
9) And more BPF kselftest improvements all over the place, from Stanislav.
10) Add simple BPF map op cache for nfp driver to batch dumps, from Jakub.
11) AF_XDP socket umem mapping improvements for 32bit archs, from Ivan.
12) Add BPF-to-BPF call and BTF line info support for s390x JIT, from Yauheni.
13) Small optimization in arm64 JIT to spare 1 insns for BPF_MOD, from Jerin.
14) Fix an error check in bpf_tcp_gen_syncookie() helper, from Petar.
15) Various minor fixes and cleanups, from Nathan, Masahiro, Masanari,
Peter, Wei, Yue.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
- Large GICv3 updates to support new PPI and SPI ranges
- Conver all alloc_fwnode() users to use PAs instead of VAs
- Add support for Marvell's MMP3 irqchip
- Add support for Amlogic Meson SM1
- Various cleanups and fixes
-----BEGIN PGP SIGNATURE-----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=PsGr
-----END PGP SIGNATURE-----
Merge tag 'irqchip-5.4' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates for Linux 5.4 from Marc Zyngier:
- Large GICv3 updates to support new PPI and SPI ranges
- Conver all alloc_fwnode() users to use PAs instead of VAs
- Add support for Marvell's MMP3 irqchip
- Add support for Amlogic Meson SM1
- Various cleanups and fixes
If we disable the compiler's auto-initialization feature, if
-fplugin-arg-structleak_plugin-byref or -ftrivial-auto-var-init=pattern
are disabled, arch_hw_breakpoint may be used before initialization after:
9a4903dde2 ("perf/hw_breakpoint: Split attribute parse and commit")
On our ARM platform, the struct step_ctrl in arch_hw_breakpoint, which
used to be zero-initialized by kzalloc(), may be used in
arch_install_hw_breakpoint() without initialization.
Signed-off-by: Mark-PK Tsai <mark-pk.tsai@mediatek.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alix Wu <alix.wu@mediatek.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: YJ Chiang <yj.chiang@mediatek.com>
Link: https://lkml.kernel.org/r/20190906060115.9460-1-mark-pk.tsai@mediatek.com
[ Minor edits. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following crash was observed:
Unable to handle kernel NULL pointer dereference at 0000000000000158
Internal error: Oops: 96000004 [#1] SMP
pc : resend_irqs+0x68/0xb0
lr : resend_irqs+0x64/0xb0
...
Call trace:
resend_irqs+0x68/0xb0
tasklet_action_common.isra.6+0x84/0x138
tasklet_action+0x2c/0x38
__do_softirq+0x120/0x324
run_ksoftirqd+0x44/0x60
smpboot_thread_fn+0x1ac/0x1e8
kthread+0x134/0x138
ret_from_fork+0x10/0x18
The reason for this is that the interrupt resend mechanism happens in soft
interrupt context, which is a asynchronous mechanism versus other
operations on interrupts. free_irq() does not take resend handling into
account. Thus, the irq descriptor might be already freed before the resend
tasklet is executed. resend_irqs() does not check the return value of the
interrupt descriptor lookup and derefences the return value
unconditionally.
1):
__setup_irq
irq_startup
check_irq_resend // activate softirq to handle resend irq
2):
irq_domain_free_irqs
irq_free_descs
free_desc
call_rcu(&desc->rcu, delayed_free_desc)
3):
__do_softirq
tasklet_action
resend_irqs
desc = irq_to_desc(irq)
desc->handle_irq(desc) // desc is NULL --> Ooops
Fix this by adding a NULL pointer check in resend_irqs() before derefencing
the irq descriptor.
Fixes: a4633adcdb ("[PATCH] genirq: add genirq sw IRQ-retrigger")
Signed-off-by: Yunfeng Ye <yeyunfeng@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Zhiqiang Liu <liuzhiqiang26@huawei.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1630ae13-5c8e-901e-de09-e740b6a426a7@huawei.com
ENOTSUPP is not supposed to be returned to userspace. This was found on an
OpenPower machine, where the RTC does not support set_alarm.
On that system, a clock_nanosleep(CLOCK_REALTIME_ALARM, ...) results in
"524 Unknown error 524"
Replace it with EOPNOTSUPP which results in the expected "95 Operation not
supported" error.
Fixes: 1c6b39ad3f (alarmtimers: Return -ENOTSUPP if no RTC device is present)
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190903171802.28314-1-cascardo@canonical.com
Add "gfp_t" support in synthetic_events, then the "gfp_t" type
parameter in some functions can be traced.
Prints the gfp flags as hex in addition to the human-readable flag
string. Example output:
whoopsie-630 [000] ...1 78.969452: testevent: bar=b20 (GFP_ATOMIC|__GFP_ZERO)
rcuc/0-11 [000] ...1 81.097555: testevent: bar=a20 (GFP_ATOMIC)
rcuc/0-11 [000] ...1 81.583123: testevent: bar=a20 (GFP_ATOMIC)
Link: http://lkml.kernel.org/r/20190712015308.9908-1-zhengjun.xing@linux.intel.com
Signed-off-by: Zhengjun Xing <zhengjun.xing@linux.intel.com>
[ Added printing of flag names ]
Signed-off-by: Tom Zanussi <zanussi@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The problem can be seen in the following two tests:
0: (bf) r3 = r10
1: (55) if r3 != 0x7b goto pc+0
2: (7a) *(u64 *)(r3 -8) = 0
3: (79) r4 = *(u64 *)(r10 -8)
..
0: (85) call bpf_get_prandom_u32#7
1: (bf) r3 = r10
2: (55) if r3 != 0x7b goto pc+0
3: (7b) *(u64 *)(r3 -8) = r0
4: (79) r4 = *(u64 *)(r10 -8)
When backtracking need to mark R4 it will mark slot fp-8.
But ST or STX into fp-8 could belong to the same block of instructions.
When backtracing is done the parent state may have fp-8 slot
as "unallocated stack". Which will cause verifier to warn
and incorrectly reject such programs.
Writes into stack via non-R10 register are rare. llvm always
generates canonical stack spill/fill.
For such pathological case fall back to conservative precision
tracking instead of rejecting.
Reported-by: syzbot+c8d66267fd2b5955287e@syzkaller.appspotmail.com
Fixes: b5dc0163d8 ("bpf: precise scalar_value tracking")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The recent change to avoid taking the expiry lock when a timer is currently
migrated missed to add a bracket at the end of the if statement leading to
compile errors. Since that commit the variable `migration_base' is always
used but it is only available on SMP configuration thus leading to another
compile error. The changelog says "The timer base and base->cpu_base
cannot be NULL in the code path", so it is safe to limit this check to SMP
configurations only.
Add the missing bracket to the if statement and hide `migration_base'
behind CONFIG_SMP bars.
[ tglx: Mark the functions inline ... ]
Fixes: 68b2c8c1e4 ("hrtimer: Don't take expiry_lock when timer is currently migrated")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190904145527.eah7z56ntwobqm6j@linutronix.de
Since BUG() and WARN() may use a trap (e.g. UD2 on x86) to
get the address where the BUG() has occurred, kprobes can not
do single-step out-of-line that instruction. So prohibit
probing on such address.
Without this fix, if someone put a kprobe on WARN(), the
kernel will crash with invalid opcode error instead of
outputing warning message, because kernel can not find
correct bug address.
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S . Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naveen N . Rao <naveen.n.rao@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/156750890133.19112.3393666300746167111.stgit@devnote2
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Thadeu Lima de Souza Cascardo reported that 'chrt' broke on recent kernels:
$ chrt -p $$
chrt: failed to get pid 26306's policy: Argument list too long
and he has root-caused the bug to the following commit increasing sched_attr
size and breaking sched_read_attr() into returning -EFBIG:
a509a7cd79 ("sched/uclamp: Extend sched_setattr() to support utilization clamping")
The other, bigger bug is that the whole sched_getattr() and sched_read_attr()
logic of checking non-zero bits in new ABI components is arguably broken,
and pretty much any extension of the ABI will spuriously break the ABI.
That's way too fragile.
Instead implement the perf syscall's extensible ABI instead, which we
already implement on the sched_setattr() side:
- if user-attributes have the same size as kernel attributes then the
logic is unchanged.
- if user-attributes are larger than the kernel knows about then simply
skip the extra bits, but set attr->size to the (smaller) kernel size
so that tooling can (in principle) handle older kernel as well.
- if user-attributes are smaller than the kernel knows about then just
copy whatever user-space can accept.
Also clean up the whole logic:
- Simplify the code flow - there's no need for 'ret' for example.
- Standardize on 'kattr/uattr' and 'ksize/usize' naming to make sure we
always know which side we are dealing with.
- Why is it called 'read' when what it does is to copy to user? This
code is so far away from VFS read() semantics that the naming is
actively confusing. Name it sched_attr_copy_to_user() instead, which
mirrors other copy_to_user() functionality.
- Move the attr->size assignment from the head of sched_getattr() to the
sched_attr_copy_to_user() function. Nothing else within the kernel
should care about the size of the structure.
With these fixes the sched_getattr() syscall now nicely supports an
extensible ABI in both a forward and backward compatible fashion, and
will also fix the chrt bug.
As an added bonus the bogus -EFBIG return is removed as well, which as
Thadeu noted should have been -E2BIG to begin with.
Reported-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Acked-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Cc: Arnaldo Carvalho de Melo <acme@infradead.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: a509a7cd79 ("sched/uclamp: Extend sched_setattr() to support utilization clamping")
Link: https://lkml.kernel.org/r/20190904075532.GA26751@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CONFIG_SHELL falls back to sh when bash is not installed on the system,
but nobody is testing such a case since bash is usually installed.
So, shell scripts invoked by CONFIG_SHELL are only tested with bash.
It makes it difficult to test whether the hashbang #!/bin/sh is real.
For example, #!/bin/sh in arch/powerpc/kernel/prom_init_check.sh is
false. (I fixed it up)
Besides, some shell scripts invoked by CONFIG_SHELL use bash-extension
and #!/bin/bash is specified as the hashbang, while CONFIG_SHELL may
not always be set to bash.
Probably, the right thing to do is to introduce BASH, which is bash by
default, and always set CONFIG_SHELL to sh. Replace $(CONFIG_SHELL)
with $(BASH) for bash scripts.
If somebody tries to add bash-extension to a #!/bin/sh script, it will
be caught in testing because /bin/sh is a symlink to dash on some major
distributions.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
A helper to find the backing page array based on a virtual address.
This also ensures we do the same vm_flags check everywhere instead
of slightly different or missing ones in a few places.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently the generic dma remap allocator gets a vm_flags passed by
the caller that is a little confusing. We just introduced a generic
vmalloc-level flag to identify the dma coherent allocations, so use
that everywhere and remove the now pointless argument.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Most dma_map_ops instances are IOMMUs that work perfectly fine in 32-bits
of IOVA space, and the generic direct mapping code already provides its
own routines that is intelligent based on the amount of memory actually
present. Wire up the dma-direct routine for the ARM direct mapping code
as well, and otherwise default to the constant 32-bit mask. This way
we only need to override it for the occasional odd IOMMU that requires
64-bit IOVA support, or IOMMU drivers that are more efficient if they
can fall back to the direct mapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma_declare_coherent_memory is something that the platform setup code
(which pretty much means the device tree these days) need to do so that
drivers can use the memory as declared by the platform. Drivers
themselves have no business calling this function.
Signed-off-by: Christoph Hellwig <hch@lst.de>
This function is entirely unused given that declared memory is
generally provided by platform setup code.
Signed-off-by: Christoph Hellwig <hch@lst.de>
CONFIG_ARCH_NO_COHERENT_DMA_MMAP is now functionally identical to
!CONFIG_MMU, so remove the separate symbol. The only difference is that
arm did not set it for !CONFIG_MMU, but arm uses a separate dma mapping
implementation including its own mmap method, which is handled by moving
the CONFIG_MMU check in dma_can_mmap so that is only applies to the
dma-direct case, just as the other ifdefs for it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Add a helper to check if DMA allocations for a specific device can be
mapped to userspace using dma_mmap_*.
Signed-off-by: Christoph Hellwig <hch@lst.de>
While the default ->mmap and ->get_sgtable implementations work for the
majority of our dma_map_ops impementations they are inherently safe
for others that don't use the page allocator or CMA and/or use their
own way of remapping not covered by the common code. So remove the
defaults if these methods are not wired up, but instead wire up the
default implementations for all safe instances.
Fixes: e1c7e32453 ("dma-mapping: always provide the dma_map_ops based implementation")
Signed-off-by: Christoph Hellwig <hch@lst.de>
The comment that says that module_event() is not static is clearly
wrong.
Signed-off-by: Nadav Amit <namit@vmware.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
strncmp(str, const, len) is error-prone.
We had better use newly introduced
str_has_prefix() instead of it.
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Signed-off-by: Daniel Thompson <daniel.thompson@linaro.org>
The play_idle resolution is 1ms. The intel_powerclamp bases the idle
duration on jiffies. The idle injection API is also using msec based
duration but has no user yet.
Unfortunately, msec based time does not fit well when we want to
inject idle cycle precisely with shallow idle state.
In order to set the scene for the incoming idle injection user, move
the precision up to usec when calling play_idle.
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Recently device pass-through stops working for Linux VM running on Hyper-V.
git-bisect shows the regression is caused by the recent commit
467a3bb974 ("PCI: hv: Allocate a named fwnode ..."), but the root cause
is that the commit d59f6617ee forgets to set the domain->fwnode for
IRQCHIP_FWNODE_NAMED*, and as a result:
1. The domain->fwnode remains to be NULL.
2. irq_find_matching_fwspec() returns NULL since "h->fwnode == fwnode" is
false, and pci_set_bus_msi_domain() sets the Hyper-V PCI root bus's
msi_domain to NULL.
3. When the device is added onto the root bus, the device's dev->msi_domain
is set to NULL in pci_set_msi_domain().
4. When a device driver tries to enable MSI-X, pci_msi_setup_msi_irqs()
calls arch_setup_msi_irqs(), which uses the native MSI chip (i.e.
arch/x86/kernel/apic/msi.c: pci_msi_controller) to set up the irqs, but
actually pci_msi_setup_msi_irqs() is supposed to call
msi_domain_alloc_irqs() with the hbus->irq_domain, which is created in
hv_pcie_init_irq_domain() and is associated with the Hyper-V chip
hv_msi_irq_chip. Consequently, the irq line is not properly set up, and
the device driver can not receive any interrupt.
Fixes: d59f6617ee ("genirq: Allow fwnode to carry name information only")
Fixes: 467a3bb974 ("PCI: hv: Allocate a named fwnode instead of an address-based one")
Reported-by: Lili Deng <v-lide@microsoft.com>
Signed-off-by: Dexuan Cui <decui@microsoft.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/PU1P153MB01694D9AF625AC335C600C5FBFBE0@PU1P153MB0169.APCP153.PROD.OUTLOOK.COM
The supported clamp indexes are defined in 'enum clamp_id', however, because
of the code logic in some of the first utilization clamping series version,
sometimes we needed to use 'unsigned int' to represent indices.
This is not more required since the final version of the uclamp_* APIs can
always use the proper enum uclamp_id type.
Fix it with a bulk rename now that we have all the bits merged.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-7-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On updates of task group (TG) clamp values, ensure that these new values
are enforced on all RUNNABLE tasks of the task group, i.e. all RUNNABLE
tasks are immediately boosted and/or capped as requested.
Do that each time we update effective clamps from cpu_util_update_eff().
Use the *cgroup_subsys_state (css) to walk the list of tasks in each
affected TG and update their RUNNABLE tasks.
Update each task by using the same mechanism used for cpu affinity masks
updates, i.e. by taking the rq lock.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-6-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When a task specific clamp value is configured via sched_setattr(2), this
value is accounted in the corresponding clamp bucket every time the task is
{en,de}qeued. However, when cgroups are also in use, the task specific
clamp values could be restricted by the task_group (TG) clamp values.
Update uclamp_cpu_inc() to aggregate task and TG clamp values. Every time a
task is enqueued, it's accounted in the clamp bucket tracking the smaller
clamp between the task specific value and its TG effective value. This
allows to:
1. ensure cgroup clamps are always used to restrict task specific requests,
i.e. boosted not more than its TG effective protection and capped at
least as its TG effective limit.
2. implement a "nice-like" policy, where tasks are still allowed to request
less than what enforced by their TG effective limits and protections
Do this by exploiting the concept of "effective" clamp, which is already
used by a TG to track parent enforced restrictions.
Apply task group clamp restrictions only to tasks belonging to a child
group. While, for tasks in the root group or in an autogroup, system
defaults are still enforced.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-5-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The clamp values are not tunable at the level of the root task group.
That's for two main reasons:
- the root group represents "system resources" which are always
entirely available from the cgroup standpoint.
- when tuning/restricting "system resources" makes sense, tuning must
be done using a system wide API which should also be available when
control groups are not.
When a system wide restriction is available, cgroups should be aware of
its value in order to know exactly how much "system resources" are
available for the subgroups.
Utilization clamping supports already the concepts of:
- system defaults: which define the maximum possible clamp values
usable by tasks.
- effective clamps: which allows a parent cgroup to constraint (maybe
temporarily) its descendants without losing the information related
to the values "requested" from them.
Exploit these two concepts and bind them together in such a way that,
whenever system default are tuned, the new values are propagated to
(possibly) restrict or relax the "effective" value of nested cgroups.
When cgroups are in use, force an update of all the RUNNABLE tasks.
Otherwise, keep things simple and do just a lazy update next time each
task will be enqueued.
Do that since we assume a more strict resource control is required when
cgroups are in use. This allows also to keep "effective" clamp values
updated in case we need to expose them to user-space.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-4-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In order to properly support hierarchical resources control, the cgroup
delegation model requires that attribute writes from a child group never
fail but still are locally consistent and constrained based on parent's
assigned resources. This requires to properly propagate and aggregate
parent attributes down to its descendants.
Implement this mechanism by adding a new "effective" clamp value for each
task group. The effective clamp value is defined as the smaller value
between the clamp value of a group and the effective clamp value of its
parent. This is the actual clamp value enforced on tasks in a task group.
Since it's possible for a cpu.uclamp.min value to be bigger than the
cpu.uclamp.max value, ensure local consistency by restricting each
"protection" (i.e. min utilization) with the corresponding "limit"
(i.e. max utilization).
Do that at effective clamps propagation to ensure all user-space write
never fails while still always tracking the most restrictive values.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-3-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The cgroup CPU bandwidth controller allows to assign a specified
(maximum) bandwidth to the tasks of a group. However this bandwidth is
defined and enforced only on a temporal base, without considering the
actual frequency a CPU is running on. Thus, the amount of computation
completed by a task within an allocated bandwidth can be very different
depending on the actual frequency the CPU is running that task.
The amount of computation can be affected also by the specific CPU a
task is running on, especially when running on asymmetric capacity
systems like Arm's big.LITTLE.
With the availability of schedutil, the scheduler is now able
to drive frequency selections based on actual task utilization.
Moreover, the utilization clamping support provides a mechanism to
bias the frequency selection operated by schedutil depending on
constraints assigned to the tasks currently RUNNABLE on a CPU.
Giving the mechanisms described above, it is now possible to extend the
cpu controller to specify the minimum (or maximum) utilization which
should be considered for tasks RUNNABLE on a cpu.
This makes it possible to better defined the actual computational
power assigned to task groups, thus improving the cgroup CPU bandwidth
controller which is currently based just on time constraints.
Extend the CPU controller with a couple of new attributes uclamp.{min,max}
which allow to enforce utilization boosting and capping for all the
tasks in a group.
Specifically:
- uclamp.min: defines the minimum utilization which should be considered
i.e. the RUNNABLE tasks of this group will run at least at a
minimum frequency which corresponds to the uclamp.min
utilization
- uclamp.max: defines the maximum utilization which should be considered
i.e. the RUNNABLE tasks of this group will run up to a
maximum frequency which corresponds to the uclamp.max
utilization
These attributes:
a) are available only for non-root nodes, both on default and legacy
hierarchies, while system wide clamps are defined by a generic
interface which does not depends on cgroups. This system wide
interface enforces constraints on tasks in the root node.
b) enforce effective constraints at each level of the hierarchy which
are a restriction of the group requests considering its parent's
effective constraints. Root group effective constraints are defined
by the system wide interface.
This mechanism allows each (non-root) level of the hierarchy to:
- request whatever clamp values it would like to get
- effectively get only up to the maximum amount allowed by its parent
c) have higher priority than task-specific clamps, defined via
sched_setattr(), thus allowing to control and restrict task requests.
Add two new attributes to the cpu controller to collect "requested"
clamp values. Allow that at each non-root level of the hierarchy.
Keep it simple by not caring now about "effective" values computation
and propagation along the hierarchy.
Update sysctl_sched_uclamp_handler() to use the newly introduced
uclamp_mutex so that we serialize system default updates with cgroup
relate updates.
Signed-off-by: Patrick Bellasi <patrick.bellasi@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutny <mkoutny@suse.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Alessio Balsini <balsini@android.com>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: Joel Fernandes <joelaf@google.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Paul Turner <pjt@google.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Perret <quentin.perret@arm.com>
Cc: Rafael J . Wysocki <rafael.j.wysocki@intel.com>
Cc: Steve Muckle <smuckle@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Todd Kjos <tkjos@google.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Link: https://lkml.kernel.org/r/20190822132811.31294-2-patrick.bellasi@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
SD_BALANCE_{FORK,EXEC} and SD_WAKE_AFFINE are stripped in sd_init()
for any sched domains with a NUMA distance greater than 2 hops
(RECLAIM_DISTANCE). The idea being that it's expensive to balance
across domains that far apart.
However, as is rather unfortunately explained in:
commit 32e45ff43e ("mm: increase RECLAIM_DISTANCE to 30")
the value for RECLAIM_DISTANCE is based on node distance tables from
2011-era hardware.
Current AMD EPYC machines have the following NUMA node distances:
node distances:
node 0 1 2 3 4 5 6 7
0: 10 16 16 16 32 32 32 32
1: 16 10 16 16 32 32 32 32
2: 16 16 10 16 32 32 32 32
3: 16 16 16 10 32 32 32 32
4: 32 32 32 32 10 16 16 16
5: 32 32 32 32 16 10 16 16
6: 32 32 32 32 16 16 10 16
7: 32 32 32 32 16 16 16 10
where 2 hops is 32.
The result is that the scheduler fails to load balance properly across
NUMA nodes on different sockets -- 2 hops apart.
For example, pinning 16 busy threads to NUMA nodes 0 (CPUs 0-7) and 4
(CPUs 32-39) like so,
$ numactl -C 0-7,32-39 ./spinner 16
causes all threads to fork and remain on node 0 until the active
balancer kicks in after a few seconds and forcibly moves some threads
to node 4.
Override node_reclaim_distance for AMD Zen.
Signed-off-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mel Gorman <mgorman@techsingularity.net>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rik van Riel <riel@surriel.com>
Cc: Suravee.Suthikulpanit@amd.com
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Thomas.Lendacky@amd.com
Cc: Tony Luck <tony.luck@intel.com>
Link: https://lkml.kernel.org/r/20190808195301.13222-3-matt@codeblueprint.co.uk
Signed-off-by: Ingo Molnar <mingo@kernel.org>
do_sched_cfs_period_timer() will refill cfs_b runtime and call
distribute_cfs_runtime to unthrottle cfs_rq, sometimes cfs_b->runtime
will allocate all quota to one cfs_rq incorrectly, then other cfs_rqs
attached to this cfs_b can't get runtime and will be throttled.
We find that one throttled cfs_rq has non-negative
cfs_rq->runtime_remaining and cause an unexpetced cast from s64 to u64
in snippet:
distribute_cfs_runtime() {
runtime = -cfs_rq->runtime_remaining + 1;
}
The runtime here will change to a large number and consume all
cfs_b->runtime in this cfs_b period.
According to Ben Segall, the throttled cfs_rq can have
account_cfs_rq_runtime called on it because it is throttled before
idle_balance, and the idle_balance calls update_rq_clock to add time
that is accounted to the task.
This commit prevents cfs_rq to be assgined new runtime if it has been
throttled until that distribute_cfs_runtime is called.
Signed-off-by: Liangyan <liangyan.peng@linux.alibaba.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: shanpeic@linux.alibaba.com
Cc: stable@vger.kernel.org
Cc: xlpang@linux.alibaba.com
Fixes: d3d9dc3302 ("sched: Throttle entities exceeding their allowed bandwidth")
Link: https://lkml.kernel.org/r/20190826121633.6538-1-liangyan.peng@linux.alibaba.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch adds a new DMA API "dma_get_merge_boundary". This function
returns the DMA merge boundary if the DMA layer can merge the segments.
This patch also adds the implementation for a new dma_map_ops pointer.
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Reviewed-by: Simon Horman <horms+renesas@verge.net.au>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull networking fixes from David Miller:
1) Fix some length checks during OGM processing in batman-adv, from
Sven Eckelmann.
2) Fix regression that caused netfilter conntrack sysctls to not be
per-netns any more. From Florian Westphal.
3) Use after free in netpoll, from Feng Sun.
4) Guard destruction of pfifo_fast per-cpu qdisc stats with
qdisc_is_percpu_stats(), from Davide Caratti. Similar bug is fixed
in pfifo_fast_enqueue().
5) Fix memory leak in mld_del_delrec(), from Eric Dumazet.
6) Handle neigh events on internal ports correctly in nfp, from John
Hurley.
7) Clear SKB timestamp in NF flow table code so that it does not
confuse fq scheduler. From Florian Westphal.
8) taprio destroy can crash if it is invoked in a failure path of
taprio_init(), because the list head isn't setup properly yet and
the list del is unconditional. Perform the list add earlier to
address this. From Vladimir Oltean.
9) Make sure to reapply vlan filters on device up, in aquantia driver.
From Dmitry Bogdanov.
10) sgiseeq driver releases DMA memory using free_page() instead of
dma_free_attrs(). From Christophe JAILLET.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (58 commits)
net: seeq: Fix the function used to release some memory in an error handling path
enetc: Add missing call to 'pci_free_irq_vectors()' in probe and remove functions
net: bcmgenet: use ethtool_op_get_ts_info()
tc-testing: don't hardcode 'ip' in nsPlugin.py
net: dsa: microchip: add KSZ8563 compatibility string
dt-bindings: net: dsa: document additional Microchip KSZ8563 switch
net: aquantia: fix out of memory condition on rx side
net: aquantia: linkstate irq should be oneshot
net: aquantia: reapply vlan filters on up
net: aquantia: fix limit of vlan filters
net: aquantia: fix removal of vlan 0
net/sched: cbs: Set default link speed to 10 Mbps in cbs_set_port_rate
taprio: Set default link speed to 10 Mbps in taprio_set_picos_per_byte
taprio: Fix kernel panic in taprio_destroy
net: dsa: microchip: fill regmap_config name
rxrpc: Fix lack of conn cleanup when local endpoint is cleaned up [ver #2]
net: stmmac: dwmac-rk: Don't fail if phy regulator is absent
amd-xgbe: Fix error path in xgbe_mod_init()
netfilter: nft_meta_bridge: Fix get NFT_META_BRI_IIFVPROTO in network byteorder
mac80211: Correctly set noencrypt for PAE frames
...
The name tracing_reset() was a misnomer, as it really only reset a single
CPU buffer. Rename it to tracing_reset_cpu() and also make it static and
remove the prototype from trace.h, as it is only used in a single function.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
As the max stack tracer algorithm is not that easy to understand from the
code, add comments that explain the algorithm and mentions how
ARCH_FTRACE_SHIFT_STACK_TRACER affects it.
Link: http://lkml.kernel.org/r/20190806123455.487ac02b@gandalf.local.home
Suggested-by: Joel Fernandes <joel@joelfernandes.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Most archs (well at least x86) store the function call return address on the
stack before storing the local variables for the function. The max stack
tracer depends on this in its algorithm to display the stack size of each
function it finds in the back trace.
Some archs (arm64), may store the return address (from its link register)
just before calling a nested function. There's no reason to save the link
register on leaf functions, as it wont be updated. This breaks the algorithm
of the max stack tracer.
Add a new define ARCH_FTRACE_SHIFT_STACK_TRACER that an architecture may set
if it stores the return address (link register) after it stores the
function's local variables, and have the stack trace shift the values of the
mapped stack size to the appropriate functions.
Link: 20190802094103.163576-1-jiping.ma2@windriver.com
Reported-by: Jiping Ma <jiping.ma2@windriver.com>
Acked-by: Will Deacon <will@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add immediate string parameter (\"string") support to
probe events. This allows you to specify an immediate
(or dummy) parameter instead of fetching a string from
memory.
This feature looks odd, but imagine that you put a probe
on a code to trace some string data. If the code is
compiled into 2 instructions and 1 instruction has a
string on memory but other has no string since it is
optimized out. In that case, you can not fold those into
one event, even if ftrace supported multiple probes on
one event. With this feature, you can set a dummy string
like foo=\"(optimized)":string instead of something
like foo=+0(+0(%bp)):string.
Link: http://lkml.kernel.org/r/156095691687.28024.13372712423865047991.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add immediate value parameter (\1234) support to
probe events. This allows you to specify an immediate
(or dummy) parameter instead of fetching from memory
or register.
This feature looks odd, but imagine when you put a probe
on a code to trace some data. If the code is compiled into
2 instructions and 1 instruction has a value but other has
nothing since it is optimized out.
In that case, you can not fold those into one event, even
if ftrace supported multiple probes on one event.
With this feature, you can set a dummy value like
foo=\deadbeef instead of something like foo=%di.
Link: http://lkml.kernel.org/r/156095690733.28024.13258186548822649469.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add per-probe delete method from one event passing the head of
definition. In other words, the events which match the head
N parameters are deleted.
Link: http://lkml.kernel.org/r/156095689811.28024.221706761151739433.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Allow user to delete a probe from event. This is done by head
match. For example, if we have 2 probes on an event
$ cat kprobe_events
p:kprobes/testprobe _do_fork r1=%ax r2=%dx
p:kprobes/testprobe idle_fork r1=%ax r2=%cx
Then you can remove one of them by passing the head of definition
which identify the probe.
$ echo "-:kprobes/testprobe idle_fork" >> kprobe_events
Link: http://lkml.kernel.org/r/156095688848.28024.15798690082378432435.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Allow user to define several probes on one uprobe event.
Note that this only support appending method. So deleting
event will delete all probes on the event.
Link: http://lkml.kernel.org/r/156095687876.28024.13840331032234992863.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add multi-probe per one event support to kprobe events.
User can define several different probes on one trace event
if those events have same "event signature",
e.g.
# echo p:testevent _do_fork > kprobe_events
# echo p:testevent fork_idle >> kprobe_events
# kprobe_events
p:kprobes/testevent _do_fork
p:kprobes/testevent fork_idle
The event signature is defined by kprobe type (retprobe or not),
the number of args, argument names, and argument types.
Note that this only support appending method. Delete event
operation will delete all probes on the event.
Link: http://lkml.kernel.org/r/156095686913.28024.9357292202316540742.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Pass extra arguments to match operation for checking
exact match. If the event doesn't support exact match,
it will be ignored.
Link: http://lkml.kernel.org/r/156095685930.28024.10405547027475590975.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When user gives an event name to delete, delete all
matched events instead of the first one.
This means if there are several events which have same
name but different group (subsystem) name, those are
removed if user passed only the event name, e.g.
# cat kprobe_events
p:group1/testevent _do_fork
p:group2/testevent fork_idle
# echo -:testevent >> kprobe_events
# cat kprobe_events
#
Link: http://lkml.kernel.org/r/156095684958.28024.16597826267117453638.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Split the trace_event related data from trace_probe data structure
and introduce trace_probe_event data structure for its folder.
This trace_probe_event data structure can have multiple trace_probe.
Link: http://lkml.kernel.org/r/156095683995.28024.7552150340561557873.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Allow kprobes which do not modify regs->ip, coexist with livepatch
by dropping FTRACE_OPS_FL_IPMODIFY from ftrace_ops.
User who wants to modify regs->ip (e.g. function fault injection)
must set a dummy post_handler to its kprobes when registering.
However, if such regs->ip modifying kprobes is set on a function,
that function can not be livepatched.
Link: http://lkml.kernel.org/r/156403587671.30117.5233558741694155985.stgit@devnote2
Acked-by: Joe Lawrence <joe.lawrence@redhat.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Make exported ftrace function not static
- Fix NULL pointer dereference in reading probes as they are created
- Fix NULL pointer dereference in k/uprobe clean up path
- Various documentation fixes
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXWpTNRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qpXtAPsGoHDHkgPIyl9bnV0oZfwLrAl4qEyg
RpVp9ZMcG4UtMwEAp/SXRFzvL+EUiKyd1U3FZy2jhVec3+hX7SzIGqgONA4=
=ee8V
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Small fixes and minor cleanups for tracing:
- Make exported ftrace function not static
- Fix NULL pointer dereference in reading probes as they are created
- Fix NULL pointer dereference in k/uprobe clean up path
- Various documentation fixes"
* tag 'trace-v5.3-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Correct kdoc formats
ftrace/x86: Remove mcount() declaration
tracing/probe: Fix null pointer dereference
tracing: Make exported ftrace_set_clr_event non-static
ftrace: Check for successful allocation of hash
ftrace: Check for empty hash and comment the race with registering probes
ftrace: Fix NULL pointer dereference in t_probe_next()
Fix the following kdoc warnings:
kernel/trace/trace.c:1579: warning: Function parameter or member 'tr' not described in 'update_max_tr_single'
kernel/trace/trace.c:1579: warning: Function parameter or member 'tsk' not described in 'update_max_tr_single'
kernel/trace/trace.c:1579: warning: Function parameter or member 'cpu' not described in 'update_max_tr_single'
kernel/trace/trace.c:1776: warning: Function parameter or member 'type' not described in 'register_tracer'
kernel/trace/trace.c:2239: warning: Function parameter or member 'task' not described in 'tracing_record_taskinfo'
kernel/trace/trace.c:2239: warning: Function parameter or member 'flags' not described in 'tracing_record_taskinfo'
kernel/trace/trace.c:2269: warning: Function parameter or member 'prev' not described in 'tracing_record_taskinfo_sched_switch'
kernel/trace/trace.c:2269: warning: Function parameter or member 'next' not described in 'tracing_record_taskinfo_sched_switch'
kernel/trace/trace.c:2269: warning: Function parameter or member 'flags' not described in 'tracing_record_taskinfo_sched_switch'
kernel/trace/trace.c:3078: warning: Function parameter or member 'ip' not described in 'trace_vbprintk'
kernel/trace/trace.c:3078: warning: Function parameter or member 'fmt' not described in 'trace_vbprintk'
kernel/trace/trace.c:3078: warning: Function parameter or member 'args' not described in 'trace_vbprintk'
Link: http://lkml.kernel.org/r/20190828052549.2472-2-jakub.kicinski@netronome.com
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The function ftrace_set_clr_event is declared static and marked
EXPORT_SYMBOL_GPL(), which is at best an odd combination. Because the
function was decided to be a part of API, this commit removes the static
attribute and adds the declaration to the header.
Link: http://lkml.kernel.org/r/20190704172110.27041-1-efremov@linux.com
Fixes: f45d1225ad ("tracing: Kernel access to Ftrace instances")
Reviewed-by: Joe Jin <joe.jin@oracle.com>
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Daniel Borkmann says:
====================
pull-request: bpf 2019-08-31
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix 32-bit zero-extension during constant blinding which
has been causing a regression on ppc64, from Naveen.
2) Fix a latency bug in nfp driver when updating stack index
register, from Jiong.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
In register_ftrace_function_probe(), we are not checking the return
value of alloc_and_copy_ftrace_hash(). The subsequent call to
ftrace_match_records() may end up dereferencing the same. Add a check to
ensure this doesn't happen.
Link: http://lkml.kernel.org/r/26e92574f25ad23e7cafa3cf5f7a819de1832cbe.1562249521.git.naveen.n.rao@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Fixes: 1ec3a81a0c ("ftrace: Have each function probe use its own ftrace_ops")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The race between adding a function probe and reading the probes that exist
is very subtle. It needs a comment. Also, the issue can also happen if the
probe has has the EMPTY_HASH as its func_hash.
Cc: stable@vger.kernel.org
Fixes: 7b60f3d876 ("ftrace: Dynamically create the probe ftrace_ops for the trace_array")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
LTP testsuite on powerpc results in the below crash:
Unable to handle kernel paging request for data at address 0x00000000
Faulting instruction address: 0xc00000000029d800
Oops: Kernel access of bad area, sig: 11 [#1]
LE SMP NR_CPUS=2048 NUMA PowerNV
...
CPU: 68 PID: 96584 Comm: cat Kdump: loaded Tainted: G W
NIP: c00000000029d800 LR: c00000000029dac4 CTR: c0000000001e6ad0
REGS: c0002017fae8ba10 TRAP: 0300 Tainted: G W
MSR: 9000000000009033 <SF,HV,EE,ME,IR,DR,RI,LE> CR: 28022422 XER: 20040000
CFAR: c00000000029d90c DAR: 0000000000000000 DSISR: 40000000 IRQMASK: 0
...
NIP [c00000000029d800] t_probe_next+0x60/0x180
LR [c00000000029dac4] t_mod_start+0x1a4/0x1f0
Call Trace:
[c0002017fae8bc90] [c000000000cdbc40] _cond_resched+0x10/0xb0 (unreliable)
[c0002017fae8bce0] [c0000000002a15b0] t_start+0xf0/0x1c0
[c0002017fae8bd30] [c0000000004ec2b4] seq_read+0x184/0x640
[c0002017fae8bdd0] [c0000000004a57bc] sys_read+0x10c/0x300
[c0002017fae8be30] [c00000000000b388] system_call+0x5c/0x70
The test (ftrace_set_ftrace_filter.sh) is part of ftrace stress tests
and the crash happens when the test does 'cat
$TRACING_PATH/set_ftrace_filter'.
The address points to the second line below, in t_probe_next(), where
filter_hash is dereferenced:
hash = iter->probe->ops.func_hash->filter_hash;
size = 1 << hash->size_bits;
This happens due to a race with register_ftrace_function_probe(). A new
ftrace_func_probe is created and added into the func_probes list in
trace_array under ftrace_lock. However, before initializing the filter,
we drop ftrace_lock, and re-acquire it after acquiring regex_lock. If
another process is trying to read set_ftrace_filter, it will be able to
acquire ftrace_lock during this window and it will end up seeing a NULL
filter_hash.
Fix this by just checking for a NULL filter_hash in t_probe_next(). If
the filter_hash is NULL, then this probe is just being added and we can
simply return from here.
Link: http://lkml.kernel.org/r/05e021f757625cbbb006fad41380323dbe4e3b43.1562249521.git.naveen.n.rao@linux.vnet.ibm.com
Cc: stable@vger.kernel.org
Fixes: 7b60f3d876 ("ftrace: Dynamically create the probe ftrace_ops for the trace_array")
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This branch has some cross-arch patches that are a prequisite for the
SVM work. They're in a topic branch in case any of the other arch
maintainers want to merge them to resolve conflicts.
The memory allocated for the atomic pool needs to have the same
mapping attributes that we use for remapping, so use
pgprot_dmacoherent instead of open coding it. Also deduct a
suitable zone to allocate the memory from based on the presence
of the DMA zones.
Signed-off-by: Christoph Hellwig <hch@lst.de>
arch_dma_mmap_pgprot is used for two things:
1) to override the "normal" uncached page attributes for mapping
memory coherent to devices that can't snoop the CPU caches
2) to provide the special DMA_ATTR_WRITE_COMBINE semantics on older
arm systems and some mips platforms
Replace one with the pgprot_dmacoherent macro that is already provided
by arm and much simpler to use, and lift the DMA_ATTR_WRITE_COMBINE
handling to common code with an explicit arch opt-in.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org> # m68k
Acked-by: Paul Burton <paul.burton@mips.com> # mips
On architectures that discard .exit.* sections at runtime, a
warning is printed for each jump label that is used within an
in-kernel __exit annotated function:
can't patch jump_label at ehci_hcd_cleanup+0x8/0x3c
WARNING: CPU: 0 PID: 1 at kernel/jump_label.c:410 __jump_label_update+0x12c/0x138
As these functions will never get executed (they are free'd along
with the rest of initmem) - we do not need to patch them and should
not display any warnings.
The warning is displayed because the test required to satisfy
jump_entry_is_init is based on init_section_contains (__init_begin to
__init_end) whereas the test in __jump_label_update is based on
init_kernel_text (_sinittext to _einittext) via kernel_text_address).
Fixes: 1948367768 ("jump_label: Annotate entries that operate on __init code earlier")
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
The state tracking changes broke the expiry active check by not writing to
it and instead sitting timers_active, which is already set.
That's not a big issue as the actual expiry is protected by sighand lock,
so concurrent handling is not possible. That means that the second task
which invokes that function executes the expiry code for nothing.
Write to the proper flag.
Also add a check whether the flag is set into check_process_timers(). That
check had been missing in the code before the rework already. The check for
another task handling the expiry of process wide timers was only done in
the fastpath check. If the fastpath check returns true because a per task
timer expired, then the checking of process wide timers was done in
parallel which is as explained above just a waste of cycles.
Fixes: 244d49e306 ("posix-cpu-timers: Move state tracking to struct posix_cputimers")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Frederic Weisbecker <frederic@kernel.org>
- Fix GICv2 emulation bug (KVM)
- Fix deadlock in virtual GIC interrupt injection code (KVM)
- Fix kprobes blacklist init failure due to broken kallsyms lookup
-----BEGIN PGP SIGNATURE-----
iQEzBAABCgAdFiEEPxTL6PPUbjXGY88ct6xw3ITBYzQFAl1mW/0ACgkQt6xw3ITB
YzQWEQgAnG+20c1uzPqIEME3o0bCXsci0I1w4yPYPH/NVrfmJdAjfway/cLZlMCh
JYKBTc392kfYXgzAvMqvjNe+9O/qg9MnMxV7Afjfk9e0k+41Kcw/7U39/B6q4yOg
zIz4YW6SdbbbUfY9VgR8SjsZ3HwJoP8YVNEv3W259funtFHkKDO35h1iG1f57GWL
UELjEnag9dmCH35ykt7+SC4woBGjOQnic2XLSS7VZuU/26TfnUyo2HCdDcLcViCZ
DHDQgaHAscb+tgJjeNtNEeRu+GPBG9LOhPw4EpBjGHeoJla7z74GOJPMEt4Ufoqd
qG9TPfOFAFM30/PAdlWF3SjfzqK3PA==
=WYzY
-----END PGP SIGNATURE-----
Merge tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 fixes from Will Deacon:
"Hot on the heels of our last set of fixes are a few more for -rc7.
Two of them are fixing issues with our virtual interrupt controller
implementation in KVM/arm, while the other is a longstanding but
straightforward kallsyms fix which was been acked by Masami and
resolves an initialisation failure in kprobes observed on arm64.
- Fix GICv2 emulation bug (KVM)
- Fix deadlock in virtual GIC interrupt injection code (KVM)
- Fix kprobes blacklist init failure due to broken kallsyms lookup"
* tag 'arm64-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux:
KVM: arm/arm64: vgic-v2: Handle SGI bits in GICD_I{S,C}PENDR0 as WI
KVM: arm/arm64: vgic: Fix potential deadlock when ap_list is long
kallsyms: Don't let kallsyms_lookup_size_offset() fail on retrieving the first symbol
sched_timer must be initialized with the _HARD mode suffix to ensure expiry
in hard interrupt context on RT.
The previous conversion to HARD expiry mode missed on one instance in
tick_nohz_switch_to_nohz(). Fix it up.
Fixes: 902a9f9c50 ("tick: Mark tick related hrtimers to expiry in hard interrupt context")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190823113845.12125-3-bigeasy@linutronix.de
When CONFIG_CPUMASK_OFFSTACK isn't enabled, 'cpumask_var_t' is as
'typedef struct cpumask cpumask_var_t[1]',
so the argument 'node_to_cpumask' alloc_nodes_vectors() can't be declared
as 'const cpumask_var_t *'
Fixes the following warning:
kernel/irq/affinity.c: In function '__irq_build_affinity_masks':
alloc_nodes_vectors(numvecs, node_to_cpumask, cpu_mask,
^
kernel/irq/affinity.c:128:13: note: expected 'const struct cpumask (*)[1]' but argument is of type 'struct cpumask (*)[1]'
static void alloc_nodes_vectors(unsigned int numvecs,
^
Fixes: b1a5a73e64 ("genirq/affinity: Spread vectors on node according to nr_cpu ratio")
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190828085815.19931-1-ming.lei@redhat.com
Using a linear O(N) search for timer insertion affects execution time and
D-cache footprint badly with a larger number of timers.
Switch the storage to a timerqueue which is already used for hrtimers and
alarmtimers. It does not affect the size of struct k_itimer as it.alarm is
still larger.
The extra list head for the expiry list will go away later once the expiry
is moved into task work context.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908272129220.1939@nanos.tec.linutronix.de
Both thread and process expiry functions have the same functionality for
sending signals for soft and hard RLIMITs duplicated in 4 different
ways.
Split it out into a common function and cleanup the callsites.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.653276779@linutronix.de
The soft RLIMIT expiry code checks whether the soft limit is greater than
the hard limit. That's pointless because if the soft RLIMIT is greater than
the hard RLIMIT then that code cannot be reached as the hard RLIMIT check
is before that and already killed the process.
Remove it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.548747613@linutronix.de
Instead of dividing A to match the units of B it's more efficient to
multiply B to match the units of A.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.458286860@linutronix.de
With the array based samples and expiry cache, the expiry function can use
a loop to collect timers from the clock specific lists.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.365469982@linutronix.de
Deactivation of the expiry cache is done by setting all clock caches to
0. That requires to have a check for zero in all places which update the
expiry cache:
if (cache == 0 || new < cache)
cache = new;
Use U64_MAX as the deactivated value, which allows to remove the zero
checks when updating the cache and reduces it to the obvious check:
if (new < cache)
cache = new;
This also removes the weird workaround in do_prlimit() which was required
to convert a RLIMIT_CPU value of 0 (immediate expiry) to 1 because handing
in 0 to the posix CPU timer code would have effectively disarmed it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.275086128@linutronix.de
The comment above the function which arms RLIMIT_CPU in the posix CPU timer
code makes no sense at all. It claims that the kernel does not return an
error code when it rejected the attempt to set RLIMIT_CPU. That's clearly
bogus as the code does an error check and the rlimit is only set and
activated when the permission checks are ok. In case of a rejection an
appropriate error code is returned.
This is a historical and outdated comment which got dragged along even when
the rlimit handling code was rewritten.
Replace it with an explanation why the setup function is not called when
the rlimit value is RLIM_INFINITY and how the 'disarming' is handled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.185511287@linutronix.de
The RTIME limit expiry code does not check the hard RTTIME limit for
INFINITY, i.e. being disabled. Add it.
While this could be considered an ABI breakage if something would depend on
this behaviour. Though it's highly unlikely to have an effect because
RLIM_INFINITY is at minimum INT_MAX and the RTTIME limit is in seconds, so
the timer would fire after ~68 years.
Adding this obvious correct limit check also allows further consolidation
of that code and is a prerequisite for cleaning up the 0 based checks and
the rlimit setter code.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192922.078293002@linutronix.de
Now that the abused struct task_cputime is gone, it's more natural to
bundle the expiry cache and the list head of each clock into a struct and
have an array of those structs.
Follow the hrtimer naming convention of 'bases' and rename the expiry cache
to 'nextevt' and adapt all usage sites.
Generates also better code .text size shrinks by 80 bytes.
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908262021140.1939@nanos.tec.linutronix.de
The last users of the magic struct cputime based expiry cache are
gone. Remove the leftovers.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.790209622@linutronix.de
The expiry cache is an array indexed by clock ids. The new sample functions
allow to retrieve a corresponding array of samples.
Convert the fastpath expiry checks to make use of the new sample functions
and do the comparisons on the sample and the expiry array.
Make the check for the expiry array being zero array based as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.695481430@linutronix.de
Instead of using task_cputime and doing the addition of utime and stime at
all call sites, it's way simpler to have a sample array which allows
indexed based checks against the expiry cache array.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.590362974@linutronix.de
Use the array based expiry cache in check_thread_timers() and convert the
store in check_process_timers() for consistency.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.408222378@linutronix.de
The expiry cache can now be accessed as an array. Replace the per clock
checks with a simple comparison of the clock indexed array member.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.303316423@linutronix.de
Now that the expiry cache can be accessed as an array, the per clock
checking can be reduced to just comparing the corresponding array elements.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.212129449@linutronix.de
Using struct task_cputime for the expiry cache is a pretty odd choice and
comes with magic defines to rename the fields for usage in the expiry
cache.
struct task_cputime is basically a u64 array with 3 members, but it has
distinct members.
The expiry cache content is different than the content of task_cputime
because
expiry[PROF] = task_cputime.stime + task_cputime.utime
expiry[VIRT] = task_cputime.utime
expiry[SCHED] = task_cputime.sum_exec_runtime
So there is no direct mapping between task_cputime and the expiry cache and
the #define based remapping is just a horrible hack.
Having the expiry cache array based allows further simplification of the
expiry code.
To avoid an all in one cleanup which is hard to review add a temporary
anonymous union into struct task_cputime which allows array based access to
it. That requires to reorder the members. Add a build time sanity check to
validate that the members are at the same place.
The union and the build time checks will be removed after conversion.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.105793824@linutronix.de
The expiry cache belongs into the posix_cputimers container where the other
cpu timers information is.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192921.014444012@linutronix.de
Per task/process data of posix CPU timers is all over the place which
makes the code hard to follow and requires ifdeffery.
Create a container to hold all this information in one place, so data is
consolidated and the ifdeffery can be confined to the posix timer header
file and removed from places like fork.
As a first step, move the cpu_timers list head array into the new struct
and clean up the initializers and simplify fork. The remaining #ifdef in
fork will be removed later.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.819418976@linutronix.de
The functions have only one caller left. No point in having them.
Move the almost duplicated code into the caller and simplify it.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.729298382@linutronix.de
Now that the sample functions have no return value anymore, the result can
simply be returned instead of using pointer indirection.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.535079278@linutronix.de
All callers hand in a valdiated clock id. Remove the return value which was
unchecked in most places anyway.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.430475832@linutronix.de
set_process_cpu_timer() checks already whether the clock id is valid. No
point in checking the return value of the sample function. That allows to
simplify the sample function later.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.339725769@linutronix.de
Extract the clock ID (PROF/VIRT/SCHED) from the clock selector and use it
as argument to the sample functions. That allows to simplify them once all
callers are fixed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.245357769@linutronix.de
Extract the clock ID (PROF/VIRT/SCHED) from the clock selector and use it
as argument to the sample functions. That allows to simplify them once all
callers are fixed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.155487201@linutronix.de
Extract the clock ID (PROF/VIRT/SCHED) from the clock selector and use it
as argument to the sample functions. That allows to simplify them once all
callers are fixed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192920.050770464@linutronix.de
cpu_clock_sample_group() and cpu_timer_sample_group() are almost the
same. Before the rename one called thread_group_cputimer() and the other
thread_group_cputime(). Really intuitive function names.
Consolidate the functions and also avoid the thread traversal when
the thread group's accounting is already active.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.960966884@linutronix.de
thread_group_cputimer() is a complete misnomer. The function does two things:
- For arming process wide timers it makes sure that the atomic time
storage is up to date. If no cpu timer is armed yet, then the atomic
time storage is not updated by the scheduler for performance reasons.
In that case a full summing up of all threads needs to be done and the
update needs to be enabled.
- Samples the current time into the caller supplied storage.
Rename it to thread_group_start_cputime(), make it static and fixup the
callsite.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.869350319@linutronix.de
The thread group accounting is active, otherwise the expiry function would
not be running. Sample the thread group time directly.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.780348088@linutronix.de
get_itimer() locks sighand lock and checks whether the timer is already
expired. If it is not expired then the thread group cputime accounting is
already enabled. Use the sampling function not the one which is meant for
starting a timer.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.689713638@linutronix.de
get_itimer() needs a sample of the current thread group cputime. It invokes
thread_group_cputimer() - which is a misnomer. That function also starts
eventually the group cputime accouting which is bogus because the
accounting is already active when a timer is armed.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.599658199@linutronix.de
Replace the next slightly different copy of permission checks. That also
removes the necessarity to check the return value of the sample functions
because the clock id is already validated.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190821192919.414813172@linutronix.de
The code contains three slightly different copies of validating whether a
given clock resolves to a valid task and whether the current caller has
permissions to access it.
Create central functions. Replace check_clock() as a first step and rename
it to something sensible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821192919.326097175@linutronix.de
In some cases, ordinary (non-AUX) events can generate data for AUX events.
For example, PEBS events can come out as records in the Intel PT stream
instead of their usual DS records, if configured to do so.
One requirement for such events is to consistently schedule together, to
ensure that the data from the "AUX output" events isn't lost while their
corresponding AUX event is not scheduled. We use grouping to provide this
guarantee: an "AUX output" event can be added to a group where an AUX event
is a group leader, and provided that the former supports writing to the
latter.
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: kan.liang@linux.intel.com
Link: https://lkml.kernel.org/r/20190806084606.4021-2-alexander.shishkin@linux.intel.com
Fast switching path only emits an event for the CPU of interest, whereas the
regular path emits an event for all the CPUs that had their frequency changed,
i.e. all the CPUs sharing the same policy.
With the current behavior, looking at cpu_frequency event for a given CPU that
is using the fast switching path will not give the correct frequency signal.
Signed-off-by: Douglas RAILLARD <douglas.raillard@arm.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Introduce BPF_F_TEST_STATE_FREQ flag to stress test parentage chain
and state pruning.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Pull networking fixes from David Miller:
1) Use 32-bit index for tails calls in s390 bpf JIT, from Ilya
Leoshkevich.
2) Fix missed EPOLLOUT events in TCP, from Eric Dumazet. Same fix for
SMC from Jason Baron.
3) ipv6_mc_may_pull() should return 0 for malformed packets, not
-EINVAL. From Stefano Brivio.
4) Don't forget to unpin umem xdp pages in error path of
xdp_umem_reg(). From Ivan Khoronzhuk.
5) Fix sta object leak in mac80211, from Johannes Berg.
6) Fix regression by not configuring PHYLINK on CPU port of bcm_sf2
switches. From Florian Fainelli.
7) Revert DMA sync removal from r8169 which was causing regressions on
some MIPS Loongson platforms. From Heiner Kallweit.
8) Use after free in flow dissector, from Jakub Sitnicki.
9) Fix NULL derefs of net devices during ICMP processing across
collect_md tunnels, from Hangbin Liu.
10) proto_register() memory leaks, from Zhang Lin.
11) Set NLM_F_MULTI flag in multipart netlink messages consistently,
from John Fastabend.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (66 commits)
r8152: Set memory to all 0xFFs on failed reg reads
openvswitch: Fix conntrack cache with timeout
ipv4: mpls: fix mpls_xmit for iptunnel
nexthop: Fix nexthop_num_path for blackhole nexthops
net: rds: add service level support in rds-info
net: route dump netlink NLM_F_MULTI flag missing
s390/qeth: reject oversized SNMP requests
sock: fix potential memory leak in proto_register()
MAINTAINERS: Add phylink keyword to SFF/SFP/SFP+ MODULE SUPPORT
xfrm/xfrm_policy: fix dst dev null pointer dereference in collect_md mode
ipv4/icmp: fix rt dst dev null pointer dereference
openvswitch: Fix log message in ovs conntrack
bpf: allow narrow loads of some sk_reuseport_md fields with offset > 0
bpf: fix use after free in prog symbol exposure
bpf: fix precision tracking in presence of bpf2bpf calls
flow_dissector: Fix potential use-after-free on BPF_PROG_DETACH
Revert "r8169: remove not needed call to dma_sync_single_for_device"
ipv6: propagate ipv6_add_dev's error returns out of ipv6_find_idev
net/ncsi: Fix the payload copying for the request coming from Netlink
qed: Add cleanup in qed_slowpath_start()
...
An arm64 kernel configured with
CONFIG_KPROBES=y
CONFIG_KALLSYMS=y
# CONFIG_KALLSYMS_ALL is not set
CONFIG_KALLSYMS_BASE_RELATIVE=y
reports the following kprobe failure:
[ 0.032677] kprobes: failed to populate blacklist: -22
[ 0.033376] Please take care of using kprobes.
It appears that kprobe fails to retrieve the symbol at address
0xffff000010081000, despite this symbol being in System.map:
ffff000010081000 T __exception_text_start
This symbol is part of the first group of aliases in the
kallsyms_offsets array (symbol names generated using ugly hacks in
scripts/kallsyms.c):
kallsyms_offsets:
.long 0x1000 // do_undefinstr
.long 0x1000 // efi_header_end
.long 0x1000 // _stext
.long 0x1000 // __exception_text_start
.long 0x12b0 // do_cp15instr
Looking at the implementation of get_symbol_pos(), it returns the
lowest index for aliasing symbols. In this case, it return 0.
But kallsyms_lookup_size_offset() considers 0 as a failure, which
is obviously wrong (there is definitely a valid symbol living there).
In turn, the kprobe blacklisting stops abruptly, hence the original
error.
A CONFIG_KALLSYMS_ALL kernel wouldn't fail as there is always
some random symbols at the beginning of this array, which are never
looked up via kallsyms_lookup_size_offset.
Fix it by considering that get_symbol_pos() is always successful
(which is consistent with the other uses of this function).
Fixes: ffc5089196 ("[PATCH] Create kallsyms_lookup_size_offset()")
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Will Deacon <will@kernel.org>
Now __irq_build_affinity_masks() spreads vectors evenly per node, but there
is a case that not all vectors have been spread when each numa node has a
different number of CPUs which triggers the warning in the spreading code.
Improve the spreading algorithm by
- assigning vectors according to the ratio of the number of CPUs on a node
to the number of remaining CPUs.
- running the assignment from smaller nodes to bigger nodes to guarantee
that every active node gets allocated at least one vector.
This ensures that all vectors are spread out. Asided of that the spread
becomes more fair if the nodes have different number of CPUs.
For example, on the following machine:
CPU(s): 16
On-line CPU(s) list: 0-15
Thread(s) per core: 1
Core(s) per socket: 8
Socket(s): 2
NUMA node(s): 2
...
NUMA node0 CPU(s): 0,1,3,5-9,11,13-15
NUMA node1 CPU(s): 2,4,10,12
When a driver requests to allocate 8 vectors, the following spread results:
irq 31, cpu list 2,4
irq 32, cpu list 10,12
irq 33, cpu list 0-1
irq 34, cpu list 3,5
irq 35, cpu list 6-7
irq 36, cpu list 8-9
irq 37, cpu list 11,13
irq 38, cpu list 14-15
So Node 0 has now 6 and Node 1 has 2 vectors assigned. The original
algorithm assigned 4 vectors on each node which was unfair versus Node 0.
[ tglx: Massaged changelog ]
Reported-by: Jon Derrick <jonathan.derrick@intel.com>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Jon Derrick <jonathan.derrick@intel.com>
Link: https://lkml.kernel.org/r/20190816022849.14075-3-ming.lei@redhat.com
One invariant of __irq_build_affinity_masks() is that all CPUs in the
specified masks (cpu_mask AND node_to_cpumask for each node) should be
covered during the spread. Even though all requested vectors have been
reached, it's still required to spread vectors among remained CPUs. A
similar policy has been taken in case of 'numvecs <= nodes' already.
So remove the following check inside the loop:
if (done >= numvecs)
break;
Meantime assign at least 1 vector for remaining nodes if 'numvecs' vectors
have been handled already.
Also, if the specified cpumask for one numa node is empty, simply do not
spread vectors on this node.
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190816022849.14075-2-ming.lei@redhat.com
Since BPF constant blinding is performed after the verifier pass, the
ALU32 instructions inserted for doubleword immediate loads don't have a
corresponding zext instruction. This is causing a kernel oops on powerpc
and can be reproduced by running 'test_cgroup_storage' with
bpf_jit_harden=2.
Fix this by emitting BPF_ZEXT during constant blinding if
prog->aux->verifier_zext is set.
Fixes: a4b1d3c1dd ("bpf: verifier: insert zero extension according to analysis result")
Reported-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Pull timekeeping fix from Thomas Gleixner:
"A single fix for a regression caused by the generic VDSO
implementation where a math overflow causes CLOCK_BOOTTIME to become a
random number generator"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping/vsyscall: Prevent math overflow in BOOTTIME update
Pull scheduler fix from Thomas Gleixner:
"Handle the worker management in situations where a task is scheduled
out on a PI lock contention correctly and schedule a new worker if
possible"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Schedule new worker even if PI-blocked
Pull perf fixes from Thomas Gleixner:
"Two small fixes for kprobes and perf:
- Prevent a deadlock in kprobe_optimizer() causes by reverse lock
ordering
- Fix a comment typo"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
kprobes: Fix potential deadlock in kprobe_optimizer()
perf/x86: Fix typo in comment
Pull irq fix from Thomas Gleixner:
"A single fix for a imbalanced kobject operation in the irq decriptor
code which was unearthed by the new warnings in the kobject code"
* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Properly pair kobject_del() with kobject_add()
Mergr misc fixes from Andrew Morton:
"11 fixes"
Mostly VM fixes, one psi polling fix, and one parisc build fix.
* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
mm/kasan: fix false positive invalid-free reports with CONFIG_KASAN_SW_TAGS=y
mm/zsmalloc.c: fix race condition in zs_destroy_pool
mm/zsmalloc.c: migration can leave pages in ZS_EMPTY indefinitely
mm, page_owner: handle THP splits correctly
userfaultfd_release: always remove uffd flags and clear vm_userfaultfd_ctx
psi: get poll_work to run when calling poll syscall next time
mm: memcontrol: flush percpu vmevents before releasing memcg
mm: memcontrol: flush percpu vmstats before releasing memcg
parisc: fix compilation errrors
mm, page_alloc: move_freepages should not examine struct page of reserved memory
mm/z3fold.c: fix race between migration and destruction
Two fixes for regressions in this merge window:
- select the Kconfig symbols for the noncoherent dma arch helpers
on arm if swiotlb is selected, not just for LPAE to not break then
Xen build, that uses swiotlb indirectly through swiotlb-xen
- fix the page allocator fallback in dma_alloc_contiguous if the CMA
allocation fails
-----BEGIN PGP SIGNATURE-----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=DXk9
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.3-5' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
"Two fixes for regressions in this merge window:
- select the Kconfig symbols for the noncoherent dma arch helpers on
arm if swiotlb is selected, not just for LPAE to not break then Xen
build, that uses swiotlb indirectly through swiotlb-xen
- fix the page allocator fallback in dma_alloc_contiguous if the CMA
allocation fails"
* tag 'dma-mapping-5.3-5' of git://git.infradead.org/users/hch/dma-mapping:
dma-direct: fix zone selection after an unaddressable CMA allocation
arm: select the dma-noncoherent symbols for all swiotlb builds
Only when calling the poll syscall the first time can user receive
POLLPRI correctly. After that, user always fails to acquire the event
signal.
Reproduce case:
1. Get the monitor code in Documentation/accounting/psi.txt
2. Run it, and wait for the event triggered.
3. Kill and restart the process.
The question is why we can end up with poll_scheduled = 1 but the work
not running (which would reset it to 0). And the answer is because the
scheduling side sees group->poll_kworker under RCU protection and then
schedules it, but here we cancel the work and destroy the worker. The
cancel needs to pair with resetting the poll_scheduled flag.
Link: http://lkml.kernel.org/r/1566357985-97781-1-git-send-email-joseph.qi@linux.alibaba.com
Signed-off-by: Jason Xing <kerneljasonxing@linux.alibaba.com>
Signed-off-by: Joseph Qi <joseph.qi@linux.alibaba.com>
Reviewed-by: Caspar Zhang <caspar@linux.alibaba.com>
Reviewed-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Borkmann says:
====================
pull-request: bpf 2019-08-24
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix verifier precision tracking with BPF-to-BPF calls, from Alexei.
2) Fix a use-after-free in prog symbol exposure, from Daniel.
3) Several s390x JIT fixes plus BE related fixes in BPF kselftests, from Ilya.
4) Fix memory leak by unpinning XDP umem pages in error path, from Ivan.
5) Fix a potential use-after-free on flow dissector detach, from Jakub.
6) Fix bpftool to close prog fd after showing metadata, from Quentin.
7) BPF kselftest config and TEST_PROGS_EXTENDED fixes, from Anders.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
syzkaller managed to trigger the warning in bpf_jit_free() which checks via
bpf_prog_kallsyms_verify_off() for potentially unlinked JITed BPF progs
in kallsyms, and subsequently trips over GPF when walking kallsyms entries:
[...]
8021q: adding VLAN 0 to HW filter on device batadv0
8021q: adding VLAN 0 to HW filter on device batadv0
WARNING: CPU: 0 PID: 9869 at kernel/bpf/core.c:810 bpf_jit_free+0x1e8/0x2a0
Kernel panic - not syncing: panic_on_warn set ...
CPU: 0 PID: 9869 Comm: kworker/0:7 Not tainted 5.0.0-rc8+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events bpf_prog_free_deferred
Call Trace:
__dump_stack lib/dump_stack.c:77 [inline]
dump_stack+0x113/0x167 lib/dump_stack.c:113
panic+0x212/0x40b kernel/panic.c:214
__warn.cold.8+0x1b/0x38 kernel/panic.c:571
report_bug+0x1a4/0x200 lib/bug.c:186
fixup_bug arch/x86/kernel/traps.c:178 [inline]
do_error_trap+0x11b/0x200 arch/x86/kernel/traps.c:271
do_invalid_op+0x36/0x40 arch/x86/kernel/traps.c:290
invalid_op+0x14/0x20 arch/x86/entry/entry_64.S:973
RIP: 0010:bpf_jit_free+0x1e8/0x2a0
Code: 02 4c 89 e2 83 e2 07 38 d0 7f 08 84 c0 0f 85 86 00 00 00 48 ba 00 02 00 00 00 00 ad de 0f b6 43 02 49 39 d6 0f 84 5f fe ff ff <0f> 0b e9 58 fe ff ff 48 b8 00 00 00 00 00 fc ff df 4c 89 e2 48 c1
RSP: 0018:ffff888092f67cd8 EFLAGS: 00010202
RAX: 0000000000000007 RBX: ffffc90001947000 RCX: ffffffff816e9d88
RDX: dead000000000200 RSI: 0000000000000008 RDI: ffff88808769f7f0
RBP: ffff888092f67d00 R08: fffffbfff1394059 R09: fffffbfff1394058
R10: fffffbfff1394058 R11: ffffffff89ca02c7 R12: ffffc90001947002
R13: ffffc90001947020 R14: ffffffff881eca80 R15: ffff88808769f7e8
BUG: unable to handle kernel paging request at fffffbfff400d000
#PF error: [normal kernel read fault]
PGD 21ffee067 P4D 21ffee067 PUD 21ffed067 PMD 9f942067 PTE 0
Oops: 0000 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 9869 Comm: kworker/0:7 Not tainted 5.0.0-rc8+ #1
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: events bpf_prog_free_deferred
RIP: 0010:bpf_get_prog_addr_region kernel/bpf/core.c:495 [inline]
RIP: 0010:bpf_tree_comp kernel/bpf/core.c:558 [inline]
RIP: 0010:__lt_find include/linux/rbtree_latch.h:115 [inline]
RIP: 0010:latch_tree_find include/linux/rbtree_latch.h:208 [inline]
RIP: 0010:bpf_prog_kallsyms_find+0x107/0x2e0 kernel/bpf/core.c:632
Code: 00 f0 ff ff 44 38 c8 7f 08 84 c0 0f 85 fa 00 00 00 41 f6 45 02 01 75 02 0f 0b 48 39 da 0f 82 92 00 00 00 48 89 d8 48 c1 e8 03 <42> 0f b6 04 30 84 c0 74 08 3c 03 0f 8e 45 01 00 00 8b 03 48 c1 e0
[...]
Upon further debugging, it turns out that whenever we trigger this
issue, the kallsyms removal in bpf_prog_ksym_node_del() was /skipped/
but yet bpf_jit_free() reported that the entry is /in use/.
Problem is that symbol exposure via bpf_prog_kallsyms_add() but also
perf_event_bpf_event() were done /after/ bpf_prog_new_fd(). Once the
fd is exposed to the public, a parallel close request came in right
before we attempted to do the bpf_prog_kallsyms_add().
Given at this time the prog reference count is one, we start to rip
everything underneath us via bpf_prog_release() -> bpf_prog_put().
The memory is eventually released via deferred free, so we're seeing
that bpf_jit_free() has a kallsym entry because we added it from
bpf_prog_load() but /after/ bpf_prog_put() from the remote CPU.
Therefore, move both notifications /before/ we install the fd. The
issue was never seen between bpf_prog_alloc_id() and bpf_prog_new_fd()
because upon bpf_prog_get_fd_by_id() we'll take another reference to
the BPF prog, so we're still holding the original reference from the
bpf_prog_load().
Fixes: 6ee52e2a3f ("perf, bpf: Introduce PERF_RECORD_BPF_EVENT")
Fixes: 74451e66d5 ("bpf: make jited programs visible in traces")
Reported-by: syzbot+bd3bba6ff3fcea7a6ec6@syzkaller.appspotmail.com
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Cc: Song Liu <songliubraving@fb.com>
While adding extra tests for precision tracking and extra infra
to adjust verifier heuristics the existing test
"calls: cross frame pruning - liveness propagation" started to fail.
The root cause is the same as described in verifer.c comment:
* Also if parent's curframe > frame where backtracking started,
* the verifier need to mark registers in both frames, otherwise callees
* may incorrectly prune callers. This is similar to
* commit 7640ead939 ("bpf: verifier: make sure callees don't prune with caller differences")
* For now backtracking falls back into conservative marking.
Turned out though that returning -ENOTSUPP from backtrack_insn() and
doing mark_all_scalars_precise() in the current parentage chain is not enough.
Depending on how is_state_visited() heuristic is creating parentage chain
it's possible that callee will incorrectly prune caller.
Fix the issue by setting precise=true earlier and more aggressively.
Before this fix the precision tracking _within_ functions that don't do
bpf2bpf calls would still work. Whereas now precision tracking is completely
disabled when bpf2bpf calls are present anywhere in the program.
No difference in cilium tests (they don't have bpf2bpf calls).
No difference in test_progs though some of them have bpf2bpf calls,
but precision tracking wasn't effective there.
Fixes: b5dc0163d8 ("bpf: precise scalar_value tracking")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The VDSO update for CLOCK_BOOTTIME has a overflow issue as it shifts the
nanoseconds based boot time offset left by the clocksource shift. That
overflows once the boot time offset becomes large enough. As a consequence
CLOCK_BOOTTIME in the VDSO becomes a random number causing applications to
misbehave.
Fix it by storing a timespec64 representation of the offset when boot time
is adjusted and add that to the MONOTONIC base time value in the vdso data
page. Using the timespec64 representation avoids a 64bit division in the
update code.
Fixes: 44f57d788e ("timekeeping: Provide a generic update_vsyscall() implementation")
Reported-by: Chris Clayton <chris2553@googlemail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Chris Clayton <chris2553@googlemail.com>
Tested-by: Vincenzo Frascino <vincenzo.frascino@arm.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1908221257580.1983@nanos.tec.linutronix.de
Pull RCU and LKMM changes from Paul E. McKenney:
- A few more RCU flavor consolidation cleanups.
- Miscellaneous fixes.
- Updates to RCU's list-traversal macros improving lockdep usability.
- Torture-test updates.
- Forward-progress improvements for no-CBs CPUs: Avoid ignoring
incoming callbacks during grace-period waits.
- Forward-progress improvements for no-CBs CPUs: Use ->cblist
structure to take advantage of others' grace periods.
- Also added a small commit that avoids needlessly inflicting
scheduler-clock ticks on callback-offloaded CPUs.
- Forward-progress improvements for no-CBs CPUs: Reduce contention
on ->nocb_lock guarding ->cblist.
- Forward-progress improvements for no-CBs CPUs: Add ->nocb_bypass
list to further reduce contention on ->nocb_lock guarding ->cblist.
- LKMM updates.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
From rdma.git
Jason Gunthorpe says:
====================
This is a collection of general cleanups for ODP to clarify some of the
flows around umem creation and use of the interval tree.
====================
The branch is based on v5.3-rc5 due to dependencies, and is being taken
into hmm.git due to dependencies in the next patches.
* odp_fixes:
RDMA/mlx5: Use odp instead of mr->umem in pagefault_mr
RDMA/mlx5: Use ib_umem_start instead of umem.address
RDMA/core: Make invalidate_range a device operation
RDMA/odp: Use kvcalloc for the dma_list and page_list
RDMA/odp: Check for overflow when computing the umem_odp end
RDMA/odp: Provide ib_umem_odp_release() to undo the allocs
RDMA/odp: Split creating a umem_odp from ib_umem_get
RDMA/odp: Make the three ways to create a umem_odp clear
RMDA/odp: Consolidate umem_odp initialization
RDMA/odp: Make it clearer when a umem is an implicit ODP umem
RDMA/odp: Iterate over the whole rbtree directly
RDMA/odp: Use the common interval tree library instead of generic
RDMA/mlx5: Fix MR npages calculation for IB_ACCESS_HUGETLB
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Warning when p == NULL and then proceeding and dereferencing p does not
make any sense as the kernel will crash with a NULL pointer dereference
right away.
Bailing out when p == NULL and returning an error code does not cure the
underlying problem which caused p to be NULL. Though it might allow to
do proper debugging.
Same applies to the clock id check in set_process_cpu_timer().
Clean them up and make them return without trying to do further damage.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.846497772@linutronix.de
PERF_EVENT_IOC_SET_BPF supports uprobes since v4.3, and tracepoints
since v4.7 via commit 04a22fae4c ("tracing, perf: Implement BPF
programs attached to uprobes"), and commit 98b5c2c65c ("perf, bpf:
allow bpf programs attach to tracepoints") respectively.
Signed-off-by: Peter Wu <peter@lekensteyn.nl>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
migration_base is used as a placeholder when an hrtimer is migrated to a
different CPU. In the case that hrtimer_cancel_wait_running() hits a timer
which is currently migrated it would pointlessly acquire the expiry lock of
the migration base, which is even not initialized.
Surely it could be initialized, but there is absolutely no point in
acquiring this lock because the timer is guaranteed not to run it's
callback for which the caller waits to finish on that base. So it would
just do the inc/lock/dec/unlock dance for nothing.
As the base switch is short and non-preemptible, there is no issue when the
wait function returns immediately.
The timer base and base->cpu_base cannot be NULL in the code path which is
invoking that, so just replace those checks with a check whether base is
migration base.
[ tglx: Updated from RT patch. Massaged changelog. Added comment. ]
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821092409.13225-4-julien.grall@arm.com
The update to timer->base is protected by the base->cpu_base->lock().
However, hrtimer_cancel_wait_running() does access it lockless. So the
compiler is allowed to refetch timer->base which can cause havoc when the
timer base is changed concurrently.
Use READ_ONCE() to prevent this.
[ tglx: Adapted from a RT patch ]
Signed-off-by: Julien Grall <julien.grall@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190821092409.13225-2-julien.grall@arm.com
Certain architecture specific operating modes (e.g., in powerpc machine
check handler that is unable to access vmalloc memory), the
search_exception_tables cannot be called because it also searches the
module exception tables if entry is not found in the kernel exception
table.
Signed-off-by: Santosh Sivaraj <santosh@fossix.org>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190820081352.8641-5-santosh@fossix.org
We should keep the case of "#define debug_align(X) (X)" for all arches
without CONFIG_HAS_STRICT_MODULE_RWX ability, which would save people, who
are sensitive to system size, a lot of memory when using modules,
especially for embedded systems. This is also the intention of the
original #ifdef... statement and still valid for now.
Note that this still keeps the effect of the fix of the following commit,
38f054d549 ("modules: always page-align module section allocations"),
since when CONFIG_ARCH_HAS_STRICT_MODULE_RWX is enabled, module pages are
aligned.
Signed-off-by: He Zhe <zhe.he@windriver.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
The network_latency and network_throughput flags for PM-QoS have not
found much use in drivers or in userspace since they were introduced.
Commit 4a733ef1be ("mac80211: remove PM-QoS listener") removed the
only user PM_QOS_NETWORK_LATENCY in the kernel a while ago and there
don't seem to be any userspace tools using the character device files
either.
PM_QOS_MEMORY_BANDWIDTH was never even added to the trace events.
Remove all the flags except cpu_dma_latency.
Signed-off-by: Amit Kucheria <amit.kucheria@linaro.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Add an ID and a device pointer to 'struct wakeup_source'. Use them to to
expose wakeup sources statistics in sysfs under
/sys/class/wakeup/wakeup<ID>/*.
Co-developed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Co-developed-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Stephen Boyd <swboyd@chromium.org>
Signed-off-by: Tri Vo <trong@android.com>
Tested-by: Kalesh Singh <kaleshsingh@google.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
kernel/power/wakelock.c duplicates wakeup source creation and
registration code from drivers/base/power/wakeup.c.
Change struct wakelock's wakeup source to a pointer and use
wakeup_source_register() function to create and register said wakeup
source. Use wakeup_source_unregister() on cleanup path.
Signed-off-by: Tri Vo <trong@android.com>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The new dma_alloc_contiguous hides if we allocate CMA or regular
pages, and thus fails to retry a ZONE_NORMAL allocation if the CMA
allocation succeeds but isn't addressable. That means we either fail
outright or dip into a small zone that might not succeed either.
Thanks to Hillf Danton for debugging this issue.
Fixes: b1d2dc009d ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Reported-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Tobias Klausmann <tobias.johannes.klausmann@mni.thm.de>
The comment above cleanup_timers() is outdated. The timers are only removed
from the task/process list heads but not modified in any other way.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.747233612@linutronix.de
The handling of a priority inversion between timer cancelling and a a not
well defined possible preemption of softirq kthread is not very clear.
Especially in the posix timers side it's unclear why there is a specific RT
wait callback.
All the nice explanations can be found in the initial changelog of
f61eff83ce (hrtimer: Prepare support for PREEMPT_RT").
Extract the detailed informations from there and put it into comments.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190820132656.GC2093@lenoir
Posix timer delete retry loops are affected by the same priority inversion
and live lock issues as the other timers.
Provide a RT specific synchronization function which keeps a reference to
the timer by holding rcu read lock to prevent the timer from being freed,
dropping the timer lock and invoking the timer specific wait function via a
new callback.
This does not yet cover posix CPU timers because they need more special
treatment on PREEMPT_RT.
[ This is folded into the original attempt which did not use a callback. ]
Originally-by: Anna-Maria Gleixenr <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lkml.kernel.org/r/20190819143801.656864506@linutronix.de
Require that arg{3,4,5} of the PR_{SET,GET}_TAGGED_ADDR_CTRL prctl and
arg2 of the PR_GET_TAGGED_ADDR_CTRL prctl() are zero rather than ignored
for future extensions.
Acked-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
Add a new command for the bpf() system call: BPF_BTF_GET_NEXT_ID is used
to cycle through all BTF objects loaded on the system.
The motivation is to be able to inspect (list) all BTF objects presents
on the system.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Implement the show_fdinfo hook for BTF FDs file operations, and make it
print the id of the BTF object. This allows for a quick retrieval of the
BTF id from its FD; or it can help understanding what type of object
(BTF) the file descriptor points to.
v2:
- Do not expose data_size, only btf_id, in FD info.
Signed-off-by: Quentin Monnet <quentin.monnet@netronome.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Use PTR_ERR_OR_ZERO rather than if(IS_ERR(...)) + PTR_ERR.
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The kvmppc ultravisor code wants a device private memory pool that is
system wide and not attached to a device. Instead of faking up one
provide a low-level memremap_pages for it.
Link: https://lore.kernel.org/r/20190818090557.17853-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Bharata B Rao <bharata@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Just clean up for early failures and then piggy back on
devm_memremap_pages_release. This helps with a pending not device managed
version of devm_memremap_pages.
Link: https://lore.kernel.org/r/20190818090557.17853-4-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Bharata B Rao <bharata@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The dev field in struct dev_pagemap is only used to print dev_name in two
places, which are at best nice to have. Just remove the field and thus
the name in those two messages.
Link: https://lore.kernel.org/r/20190818090557.17853-3-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Bharata B Rao <bharata@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Factor out the guts of devm_request_free_mem_region so that we can
implement both a device managed and a manually release version as tiny
wrappers around it.
Link: https://lore.kernel.org/r/20190818090557.17853-2-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Bharata B Rao <bharata@linux.ibm.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This is a significant simplification, it eliminates all the remaining
'hmm' stuff in mm_struct, eliminates krefing along the critical notifier
paths, and takes away all the ugly locking and abuse of page_table_lock.
mmu_notifier_get() provides the single struct hmm per struct mm which
eliminates mm->hmm.
It also directly guarantees that no mmu_notifier op callback is callable
while concurrent free is possible, this eliminates all the krefs inside
the mmu_notifier callbacks.
The remaining krefs in the range code were overly cautious, drivers are
already not permitted to free the mirror while a range exists.
Link: https://lore.kernel.org/r/20190806231548.25242-6-jgg@ziepe.ca
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Tested-by: Ralph Campbell <rcampbell@nvidia.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Systems in lockdown mode should block the kexec of untrusted kernels.
For x86 and ARM we can ensure that a kernel is trustworthy by validating
a PE signature, but this isn't possible on other architectures. On those
platforms we can use IMA digital signatures instead. Add a function to
determine whether IMA has or will verify signatures for a given event type,
and if so permit kexec_file() even if the kernel is otherwise locked down.
This is restricted to cases where CONFIG_INTEGRITY_TRUSTED_KEYRING is set
in order to prevent an attacker from loading additional keys at runtime.
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Mimi Zohar <zohar@linux.ibm.com>
Cc: Dmitry Kasatkin <dmitry.kasatkin@gmail.com>
Cc: linux-integrity@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
Disallow the use of certain perf facilities that might allow userspace to
access kernel data.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
bpf_read() and bpf_read_str() could potentially be abused to (eg) allow
private keys in kernel memory to be leaked. Disable them if the kernel
has been locked down in confidentiality mode.
Suggested-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: netdev@vger.kernel.org
cc: Chun-Yi Lee <jlee@suse.com>
cc: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: James Morris <jmorris@namei.org>
Disallow the creation of perf and ftrace kprobes when the kernel is
locked down in confidentiality mode by preventing their registration.
This prevents kprobes from being used to access kernel memory to steal
crypto data, but continues to allow the use of kprobes from signed
modules.
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: davem@davemloft.net
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
Provided an annotation for module parameters that specify hardware
parameters (such as io ports, iomem addresses, irqs, dma channels, fixed
dma buffers and other types).
Suggested-by: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
There is currently no way to verify the resume image when returning
from hibernate. This might compromise the signed modules trust model,
so until we can work with signed hibernate images we disable it when the
kernel is locked down.
Signed-off-by: Josh Boyer <jwboyer@fedoraproject.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: rjw@rjwysocki.net
Cc: pavel@ucw.cz
cc: linux-pm@vger.kernel.org
Signed-off-by: James Morris <jmorris@namei.org>
When KEXEC_SIG is not enabled, kernel should not load images through
kexec_file systemcall if the kernel is locked down.
[Modified by David Howells to fit with modifications to the previous patch
and to return -EPERM if the kernel is locked down for consistency with
other lockdowns. Modified by Matthew Garrett to remove the IMA
integration, which will be replaced by integrating with the IMA
architecture policy patches.]
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
This is a preparatory patch for kexec_file_load() lockdown. A locked down
kernel needs to prevent unsigned kernel images from being loaded with
kexec_file_load(). Currently, the only way to force the signature
verification is compiling with KEXEC_VERIFY_SIG. This prevents loading
usigned images even when the kernel is not locked down at runtime.
This patch splits KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE.
Analogous to the MODULE_SIG and MODULE_SIG_FORCE for modules, KEXEC_SIG
turns on the signature verification but allows unsigned images to be
loaded. KEXEC_SIG_FORCE disallows images without a valid signature.
Signed-off-by: Jiri Bohac <jbohac@suse.cz>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
The kexec_load() syscall permits the loading and execution of arbitrary
code in ring 0, which is something that lock-down is meant to prevent. It
makes sense to disable kexec_load() in this situation.
This does not affect kexec_file_load() syscall which can check for a
signature on the image to be booted.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <mjg59@google.com>
Acked-by: Dave Young <dyoung@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
cc: kexec@lists.infradead.org
Signed-off-by: James Morris <jmorris@namei.org>
If the kernel is locked down, require that all modules have valid
signatures that we can verify.
I have adjusted the errors generated:
(1) If there's no signature (ENODATA) or we can't check it (ENOPKG,
ENOKEY), then:
(a) If signatures are enforced then EKEYREJECTED is returned.
(b) If there's no signature or we can't check it, but the kernel is
locked down then EPERM is returned (this is then consistent with
other lockdown cases).
(2) If the signature is unparseable (EBADMSG, EINVAL), the signature fails
the check (EKEYREJECTED) or a system error occurs (eg. ENOMEM), we
return the error we got.
Note that the X.509 code doesn't check for key expiry as the RTC might not
be valid or might not have been transferred to the kernel's clock yet.
[Modified by Matthew Garrett to remove the IMA integration. This will
be replaced with integration with the IMA architecture policy
patchset.]
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Matthew Garrett <matthewgarrett@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Jessica Yu <jeyu@kernel.org>
Signed-off-by: James Morris <jmorris@namei.org>
Pull kernel thread signal handling fix from Eric Biederman:
"I overlooked the fact that kernel threads are created with all signals
set to SIG_IGN, and accidentally caused a regression in cifs and drbd
when replacing force_sig with send_sig.
This is my fix for that regression. I add a new function
allow_kernel_signal which allows kernel threads to receive signals
sent from the kernel, but continues to ignore all signals sent from
userspace. This ensures the user space interface for cifs and drbd
remain the same.
These kernel threads depend on blocking networking calls which block
until something is received or a signal is pending. Making receiving
of signals somewhat necessary for these kernel threads.
Perhaps someday we can cleanup those interfaces and remove
allow_kernel_signal. If not allow_kernel_signal is pretty trivial and
clearly documents what is going on so I don't think we will mind
carrying it"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
signal: Allow cifs and drbd to receive their terminating signals
If alloc_descs() fails before irq_sysfs_init() has run, free_desc() in the
cleanup path will call kobject_del() even though the kobject has not been
added with kobject_add().
Fix this by making the call to kobject_del() conditional on whether
irq_sysfs_init() has run.
This problem surfaced because commit aa30f47cf6 ("kobject: Add support
for default attribute groups to kobj_type") makes kobject_del() stricter
about pairing with kobject_add(). If the pairing is incorrrect, a WARNING
and backtrace occur in sysfs_remove_group() because there is no parent.
[ tglx: Add a comment to the code and make it work with CONFIG_SYSFS=n ]
Fixes: ecb3f394c5 ("genirq: Expose interrupt information through sysfs")
Signed-off-by: Michael Kelley <mikelley@microsoft.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/1564703564-4116-1-git-send-email-mikelley@microsoft.com
Switch force_irqthreads from a boot time modifiable variable to a compile
time constant when CONFIG_PREEMPT_RT is enabled.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190816160923.12855-1-bigeasy@linutronix.de
My recent to change to only use force_sig for a synchronous events
wound up breaking signal reception cifs and drbd. I had overlooked
the fact that by default kthreads start out with all signals set to
SIG_IGN. So a change I thought was safe turned out to have made it
impossible for those kernel thread to catch their signals.
Reverting the work on force_sig is a bad idea because what the code
was doing was very much a misuse of force_sig. As the way force_sig
ultimately allowed the signal to happen was to change the signal
handler to SIG_DFL. Which after the first signal will allow userspace
to send signals to these kernel threads. At least for
wake_ack_receiver in drbd that does not appear actively wrong.
So correct this problem by adding allow_kernel_signal that will allow
signals whose siginfo reports they were sent by the kernel through,
but will not allow userspace generated signals, and update cifs and
drbd to call allow_kernel_signal in an appropriate place so that their
thread can receive this signal.
Fixing things this way ensures that userspace won't be able to send
signals and cause problems, that it is clear which signals the
threads are expecting to receive, and it guarantees that nothing
else in the system will be affected.
This change was partly inspired by similar cifs and drbd patches that
added allow_signal.
Reported-by: ronnie sahlberg <ronniesahlberg@gmail.com>
Reported-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Tested-by: Christoph Böhmwalder <christoph.boehmwalder@linbit.com>
Cc: Steve French <smfrench@gmail.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Fixes: 247bc9470b ("cifs: fix rmmod regression in cifs.ko caused by force_sig changes")
Fixes: 72abe3bcf0 ("signal/cifs: Fix cifs_put_tcp_session to call send_sig instead of force_sig")
Fixes: fee109901f ("signal/drbd: Use send_sig not force_sig")
Fixes: 3cf5d076fb ("signal: Remove task parameter from force_sig")
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
klp_module_coming() is called for every module appearing in the system.
It sets obj->mod to a patched module for klp_object obj. Unfortunately
it leaves it set even if an error happens later in the function and the
patched module is not allowed to be loaded.
klp_is_object_loaded() uses obj->mod variable and could currently give a
wrong return value. The bug is probably harmless as of now.
Signed-off-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
lockdep reports the following deadlock scenario:
WARNING: possible circular locking dependency detected
kworker/1:1/48 is trying to acquire lock:
000000008d7a62b2 (text_mutex){+.+.}, at: kprobe_optimizer+0x163/0x290
but task is already holding lock:
00000000850b5e2d (module_mutex){+.+.}, at: kprobe_optimizer+0x31/0x290
which lock already depends on the new lock.
the existing dependency chain (in reverse order) is:
-> #1 (module_mutex){+.+.}:
__mutex_lock+0xac/0x9f0
mutex_lock_nested+0x1b/0x20
set_all_modules_text_rw+0x22/0x90
ftrace_arch_code_modify_prepare+0x1c/0x20
ftrace_run_update_code+0xe/0x30
ftrace_startup_enable+0x2e/0x50
ftrace_startup+0xa7/0x100
register_ftrace_function+0x27/0x70
arm_kprobe+0xb3/0x130
enable_kprobe+0x83/0xa0
enable_trace_kprobe.part.0+0x2e/0x80
kprobe_register+0x6f/0xc0
perf_trace_event_init+0x16b/0x270
perf_kprobe_init+0xa7/0xe0
perf_kprobe_event_init+0x3e/0x70
perf_try_init_event+0x4a/0x140
perf_event_alloc+0x93a/0xde0
__do_sys_perf_event_open+0x19f/0xf30
__x64_sys_perf_event_open+0x20/0x30
do_syscall_64+0x65/0x1d0
entry_SYSCALL_64_after_hwframe+0x49/0xbe
-> #0 (text_mutex){+.+.}:
__lock_acquire+0xfcb/0x1b60
lock_acquire+0xca/0x1d0
__mutex_lock+0xac/0x9f0
mutex_lock_nested+0x1b/0x20
kprobe_optimizer+0x163/0x290
process_one_work+0x22b/0x560
worker_thread+0x50/0x3c0
kthread+0x112/0x150
ret_from_fork+0x3a/0x50
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(module_mutex);
lock(text_mutex);
lock(module_mutex);
lock(text_mutex);
*** DEADLOCK ***
As a reproducer I've been using bcc's funccount.py
(https://github.com/iovisor/bcc/blob/master/tools/funccount.py),
for example:
# ./funccount.py '*interrupt*'
That immediately triggers the lockdep splat.
Fix by acquiring text_mutex before module_mutex in kprobe_optimizer().
Signed-off-by: Andrea Righi <andrea.righi@canonical.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: d5b844a2cf ("ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()")
Link: http://lkml.kernel.org/r/20190812184302.GA7010@xps-13
Signed-off-by: Ingo Molnar <mingo@kernel.org>
If a task is PI-blocked (blocking on sleeping spinlock) then we don't want to
schedule a new kworker if we schedule out due to lock contention because !RT
does not do that as well. A spinning spinlock disables preemption and a worker
does not schedule out on lock contention (but spin).
On RT the RW-semaphore implementation uses an rtmutex so
tsk_is_pi_blocked() will return true if a task blocks on it. In this case we
will now start a new worker which may deadlock if one worker is waiting on
progress from another worker. Since a RW-semaphore starts a new worker on !RT,
we should do the same on RT.
XFS is able to trigger this deadlock.
Allow to schedule new worker if the current worker is PI-blocked.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/20190816160626.12742-1-bigeasy@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Here are 4 small SPDX fixes for 5.3-rc5. A few style fixes for some
SPDX comments, added an SPDX tag for one file, and fix up some GPL
boilerplate for another file.
All of these have been in linux-next for a few weeks with no reported
issues (they are comment changes only, so that's to be expected...)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXVkVSg8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+yneygCfdBxdIl98qXA2SRDLeKl/PkSJH1gAoLwnkoKq
WK/gN0IMFf25UrItBsGe
=b31n
-----END PGP SIGNATURE-----
Merge tag 'spdx-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx
Pull SPDX fixes from Greg KH:
"Here are four small SPDX fixes for 5.3-rc5.
A few style fixes for some SPDX comments, added an SPDX tag for one
file, and fix up some GPL boilerplate for another file.
All of these have been in linux-next for a few weeks with no reported
issues (they are comment changes only, so that's to be expected...)"
* tag 'spdx-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/spdx:
i2c: stm32: Use the correct style for SPDX License Identifier
intel_th: Use the correct style for SPDX License Identifier
coccinelle: api/atomic_as_refcounter: add SPDX License Identifier
kernel/configs: Replace GPL boilerplate code with SPDX identifier
The XSKMAP did not honor the BPF_EXIST/BPF_NOEXIST flags when updating
an entry. This patch addresses that.
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
When an AF_XDP socket is released/closed the XSKMAP still holds a
reference to the socket in a "released" state. The socket will still
use the netdev queue resource, and block newly created sockets from
attaching to that queue, but no user application can access the
fill/complete/rx/tx queues. This results in that all applications need
to explicitly clear the map entry from the old "zombie state"
socket. This should be done automatically.
In this patch, the sockets tracks, and have a reference to, which maps
it resides in. When the socket is released, it will remove itself from
all maps.
Suggested-by: Bruce Richardson <bruce.richardson@intel.com>
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Rename existing bpf_map_inc_not_zero to __bpf_map_inc_not_zero to
indicate that it's caller's responsibility to do proper locking.
Create and export bpf_map_inc_not_zero wrapper that properly
locks map_idr_lock. Will be used in the next commit to
hold a map while cloning a socket.
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
- Disable NVMe power optimization related to suspend-to-idle added
recently on systems where PCIe ASPM is not able to put PCIe links
into low-power states to prevent excess power from being drawn by
the system while suspended (Rafael Wysocki).
- Make the schedutil governor handle frequency limits changes
properly in all cases (Viresh Kumar).
- Prevent the cpufreq core from treating positive values returned
by dev_pm_qos_update_request() as errors (Viresh Kumar).
-----BEGIN PGP SIGNATURE-----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=eCcy
-----END PGP SIGNATURE-----
Merge tag 'pm-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fixes from Rafael Wysocki:
"These add a check to avoid recent suspend-to-idle power regression on
systems with NVMe drives where the PCIe ASPM policy is "performance"
(or when the kernel is built without ASPM support), fix an issue
related to frequency limits in the schedutil cpufreq governor and fix
a mistake related to the PM QoS usage in the cpufreq core introduced
recently.
Specifics:
- Disable NVMe power optimization related to suspend-to-idle added
recently on systems where PCIe ASPM is not able to put PCIe links
into low-power states to prevent excess power from being drawn by
the system while suspended (Rafael Wysocki).
- Make the schedutil governor handle frequency limits changes
properly in all cases (Viresh Kumar).
- Prevent the cpufreq core from treating positive values returned by
dev_pm_qos_update_request() as errors (Viresh Kumar)"
* tag 'pm-5.3-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
nvme-pci: Allow PCI bus-level PM to be used if ASPM is disabled
PCI/ASPM: Add pcie_aspm_enabled()
cpufreq: schedutil: Don't skip freq update when limits change
cpufreq: dev_pm_qos_update_request() can return 1 on success
Use str_has_prefix() instead of strncmp() which is less
straightforward in decode_state().
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
[ rjw: Subject & changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
strncmp(str, const, len) is error-prone because len is easy to have typo.
An example is the hard-coded len has counting error or sizeof(const)
forgets - 1.
So we prefer using newly introduced str_has_prefix() to substitute
such strncmp() to make code better.
Link: http://lkml.kernel.org/r/20190809071034.17279-1-hslester96@gmail.com
Cc: "Steven Rostedt" <rostedt@goodmis.org>
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
[pmladek@suse.com: Slightly updated and reformatted the commit message.]
Signed-off-by: Petr Mladek <pmladek@suse.com>
In case of error, the function kobject_create_and_add() returns NULL
pointer not ERR_PTR(). The IS_ERR() test in the return value check
should be replaced with NULL test.
Fixes: 341dfcf8d7 ("btf: expose BTF info through sysfs")
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
- fix the handling of the bus_dma_mask in dma_get_required_mask, which
caused a regression in this merge window (Lucas Stach)
- fix a regression in the handling of DMA_ATTR_NO_KERNEL_MAPPING (me)
- fix dma_mmap_coherent to not cause page attribute mismatches on
coherent architectures like x86 (me)
-----BEGIN PGP SIGNATURE-----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=Jzmo
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.3-4' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
- fix the handling of the bus_dma_mask in dma_get_required_mask, which
caused a regression in this merge window (Lucas Stach)
- fix a regression in the handling of DMA_ATTR_NO_KERNEL_MAPPING (me)
- fix dma_mmap_coherent to not cause page attribute mismatches on
coherent architectures like x86 (me)
* tag 'dma-mapping-5.3-4' of git://git.infradead.org/users/hch/dma-mapping:
dma-mapping: fix page attributes for dma_mmap_*
dma-direct: don't truncate dma_required_mask to bus addressing capabilities
dma-direct: fix DMA_ATTR_NO_KERNEL_MAPPING
Daniel Borkmann says:
====================
The following pull-request contains BPF updates for your *net-next* tree.
There is a small merge conflict in libbpf (Cc Andrii so he's in the loop
as well):
for (i = 1; i <= btf__get_nr_types(btf); i++) {
t = (struct btf_type *)btf__type_by_id(btf, i);
if (!has_datasec && btf_is_var(t)) {
/* replace VAR with INT */
t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0);
<<<<<<< HEAD
/*
* using size = 1 is the safest choice, 4 will be too
* big and cause kernel BTF validation failure if
* original variable took less than 4 bytes
*/
t->size = 1;
*(int *)(t+1) = BTF_INT_ENC(0, 0, 8);
} else if (!has_datasec && kind == BTF_KIND_DATASEC) {
=======
t->size = sizeof(int);
*(int *)(t + 1) = BTF_INT_ENC(0, 0, 32);
} else if (!has_datasec && btf_is_datasec(t)) {
>>>>>>> 72ef80b5ee
/* replace DATASEC with STRUCT */
Conflict is between the two commits 1d4126c4e1 ("libbpf: sanitize VAR to
conservative 1-byte INT") and b03bc6853c ("libbpf: convert libbpf code to
use new btf helpers"), so we need to pick the sanitation fixup as well as
use the new btf_is_datasec() helper and the whitespace cleanup. Looks like
the following:
[...]
if (!has_datasec && btf_is_var(t)) {
/* replace VAR with INT */
t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0);
/*
* using size = 1 is the safest choice, 4 will be too
* big and cause kernel BTF validation failure if
* original variable took less than 4 bytes
*/
t->size = 1;
*(int *)(t + 1) = BTF_INT_ENC(0, 0, 8);
} else if (!has_datasec && btf_is_datasec(t)) {
/* replace DATASEC with STRUCT */
[...]
The main changes are:
1) Addition of core parts of compile once - run everywhere (co-re) effort,
that is, relocation of fields offsets in libbpf as well as exposure of
kernel's own BTF via sysfs and loading through libbpf, from Andrii.
More info on co-re: http://vger.kernel.org/bpfconf2019.html#session-2
and http://vger.kernel.org/lpc-bpf2018.html#session-2
2) Enable passing input flags to the BPF flow dissector to customize parsing
and allowing it to stop early similar to the C based one, from Stanislav.
3) Add a BPF helper function that allows generating SYN cookies from XDP and
tc BPF, from Petar.
4) Add devmap hash-based map type for more flexibility in device lookup for
redirects, from Toke.
5) Improvements to XDP forwarding sample code now utilizing recently enabled
devmap lookups, from Jesper.
6) Add support for reporting the effective cgroup progs in bpftool, from Jakub
and Takshak.
7) Fix reading kernel config from bpftool via /proc/config.gz, from Peter.
8) Fix AF_XDP umem pages mapping for 32 bit architectures, from Ivan.
9) Follow-up to add two more BPF loop tests for the selftest suite, from Alexei.
10) Add perf event output helper also for other skb-based program types, from Allan.
11) Fix a co-re related compilation error in selftests, from Yonghong.
====================
Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Bimodal behavior of rcu_do_batch() is not really suited to Google
applications like gfe servers.
When a process with millions of sockets exits, closing all files
queues two rcu callbacks per socket.
This eventually reaches the point where RCU enters an emergency
mode, where rcu_do_batch() do not return until whole queue is flushed.
Each rcu callback lasts at least 70 nsec, so with millions of
elements, we easily spend more than 100 msec without rescheduling.
Goal of this patch is to avoid the infamous message like following
"need_resched set for > 51999388 ns (52 ticks) without schedule"
We dynamically adjust the number of elements we process, instead
of 10 / INFINITE choices, we use a floor of ~1 % of current entries.
If the number is above 1000, we switch to a time based limit of 3 msec
per batch, adjustable with /sys/module/rcutree/parameters/rcu_resched_ns
Signed-off-by: Eric Dumazet <edumazet@google.com>
[ paulmck: Forward-port and remove debug statements. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
When under overload conditions, __call_rcu_nocb_wake() will wake the
no-CBs GP kthread any time the no-CBs CB kthread is asleep or there
are no ready-to-invoke callbacks, but only after a timer delay. If the
no-CBs GP kthread has a ->nocb_bypass_timer pending, the deferred wakeup
from __call_rcu_nocb_wake() is redundant. This commit therefore makes
__call_rcu_nocb_wake() avoid posting the redundant deferred wakeup if
->nocb_bypass_timer is pending. This requires adding a bit of ordering
of timer actions.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, __call_rcu_nocb_wake() advances callbacks each time that it
detects excessive numbers of callbacks, though only if it succeeds in
conditionally acquiring its leaf rcu_node structure's ->lock. Despite
the conditional acquisition of ->lock, this does increase contention.
This commit therefore avoids advancing callbacks unless there are
callbacks in ->cblist whose grace period has completed and advancing
has not yet been done during this jiffy.
Note that this decision does not take the presence of new callbacks
into account. That is because on this code path, there will always be
at least one new callback, namely the one we just enqueued.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, nocb_cb_wait() advances callbacks on each pass through its
loop, though only if it succeeds in conditionally acquiring its leaf
rcu_node structure's ->lock. Despite the conditional acquisition of
->lock, this does increase contention. This commit therefore avoids
advancing callbacks unless there are callbacks in ->cblist whose grace
period has completed.
Note that nocb_cb_wait() doesn't worry about callbacks that have not
yet been assigned a grace period. The idea is that the only reason for
nocb_cb_wait() to advance callbacks is to allow it to continue invoking
callbacks. Time will tell whether this is the correct choice.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcutree_migrate_callbacks() invokes rcu_advance_cbs() on both the
offlined CPU's ->cblist and that of the surviving CPU, then merges
them. However, after the merge, and of the offlined CPU's callbacks
that were not ready to be invoked will no longer be associated with a
grace-period number. This commit therefore invokes rcu_advance_cbs()
one more time on the merged ->cblist in order to assign a grace-period
number to these callbacks.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
When callbacks are in full flow, the common case is waiting for a
grace period, and this grace period will normally take a few jiffies to
complete. It therefore isn't all that helpful for __call_rcu_nocb_wake()
to do a synchronous wakeup in this case. This commit therefore turns this
into a timer-based deferred wakeup of the no-CBs grace-period kthread.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit causes locking, sleeping, and callback state to be printed
for no-CBs CPUs when the rcutorture writer is delayed sufficiently for
rcutorture to complain.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Use of the rcu_data structure's segmented ->cblist for no-CBs CPUs
takes advantage of unrelated grace periods, thus reducing the memory
footprint in the face of floods of call_rcu() invocations. However,
the ->cblist field is a more-complex rcu_segcblist structure which must
be protected via locking. Even though there are only three entities
which can acquire this lock (the CPU invoking call_rcu(), the no-CBs
grace-period kthread, and the no-CBs callbacks kthread), the contention
on this lock is excessive under heavy stress.
This commit therefore greatly reduces contention by provisioning
an rcu_cblist structure field named ->nocb_bypass within the
rcu_data structure. Each no-CBs CPU is permitted only a limited
number of enqueues onto the ->cblist per jiffy, controlled by a new
nocb_nobypass_lim_per_jiffy kernel boot parameter that defaults to
about 16 enqueues per millisecond (16 * 1000 / HZ). When that limit is
exceeded, the CPU instead enqueues onto the new ->nocb_bypass.
The ->nocb_bypass is flushed into the ->cblist every jiffy or when
the number of callbacks on ->nocb_bypass exceeds qhimark, whichever
happens first. During call_rcu() floods, this flushing is carried out
by the CPU during the course of its call_rcu() invocations. However,
a CPU could simply stop invoking call_rcu() at any time. The no-CBs
grace-period kthread therefore carries out less-aggressive flushing
(every few jiffies or when the number of callbacks on ->nocb_bypass
exceeds (2 * qhimark), whichever comes first). This means that the
no-CBs grace-period kthread cannot be permitted to do unbounded waits
while there are callbacks on ->nocb_bypass. A ->nocb_bypass_timer is
used to provide the needed wakeups.
[ paulmck: Apply Coverity feedback reported by Colin Ian King. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Upcoming ->nocb_lock contention-reduction work requires that the
rcu_segcblist structure's ->len field be concurrently manipulated,
but only if there are no-CBs CPUs in the kernel. This commit
therefore makes this ->len field be an atomic_long_t, but only
in CONFIG_RCU_NOCB_CPU=y kernels.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
When there are excessive numbers of callbacks, and when either the
corresponding no-CBs callback kthread is asleep or there is no more
ready-to-invoke callbacks, and when least one callback is pending,
__call_rcu_nocb_wake() will advance the callbacks, but refrain from
awakening the corresponding no-CBs grace-period kthread. However,
because rcu_advance_cbs_nowake() is used, it is possible (if a bit
unlikely) that the needed advancement could not happen due to a grace
period not being in progress. Plus there will always be at least one
pending callback due to one having just now been enqueued.
This commit therefore attempts to advance callbacks and awakens the
no-CBs grace-period kthread when there are excessive numbers of callbacks
posted and when the no-CBs callback kthread is not in a position to do
anything helpful.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The sleep/wakeup of the no-CBs grace-period kthreads is synchronized
using the ->nocb_lock of the first CPU corresponding to that kthread.
This commit provides a separate ->nocb_gp_lock for this purpose, thus
reducing contention on ->nocb_lock.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, nocb_cb_wait() unconditionally acquires the leaf rcu_node
->lock to advance callbacks when done invoking the previous batch.
It does this while holding ->nocb_lock, which means that contention on
the leaf rcu_node ->lock visits itself on the ->nocb_lock. This commit
therefore makes this lock acquisition conditional, forgoing callback
advancement when the leaf rcu_node ->lock is not immediately available.
(In this case, the no-CBs grace-period kthread will eventually do any
needed callback advancement.)
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, __call_rcu_nocb_wake() conditionally acquires the leaf rcu_node
structure's ->lock, and only afterwards does rcu_advance_cbs_nowake()
check to see if it is possible to advance callbacks without potentially
needing to awaken the grace-period kthread. Given that the no-awaken
check can be done locklessly, this commit reverses the order, so that
rcu_advance_cbs_nowake() is invoked without holding the leaf rcu_node
structure's ->lock and rcu_advance_cbs_nowake() checks the grace-period
state before conditionally acquiring that lock, thus reducing the number
of needless acquistions of the leaf rcu_node structure's ->lock.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, when the square root of the number of CPUs is rounded down
by int_sqrt(), this round-down is applied to the number of callback
kthreads per grace-period kthreads. This makes almost no difference
for large systems, but results in oddities such as three no-CBs
grace-period kthreads for a five-CPU system, which is a bit excessive.
This commit therefore causes the round-down to apply to the number of
no-CBs grace-period kthreads, so that systems with from four to eight
CPUs have only two no-CBs grace period kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
A given rcu_data structure's ->nocb_lock can be acquired very frequently
by the corresponding CPU and occasionally by the corresponding no-CBs
grace-period and callbacks kthreads. In particular, these two kthreads
will have frequent gaps between ->nocb_lock acquisitions that are roughly
a grace period in duration. This means that any excessive ->nocb_lock
contention will be due to the CPU's acquisitions, and this in turn
enables a very naive contention-avoidance strategy to be quite effective.
This commit therefore modifies rcu_nocb_lock() to first
attempt a raw_spin_trylock(), and to atomically increment a
separate ->nocb_lock_contended across a raw_spin_lock(). This new
->nocb_lock_contended field is checked in __call_rcu_nocb_wake() when
interrupts are enabled, with a spin-wait for contending acquisitions
to complete, thus allowing the kthreads a chance to acquire the lock.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, the code provides an extra wakeup for the no-CBs grace-period
kthread if one of its CPUs is generating excessive numbers of callbacks.
But satisfying though it is to wake something up when things are going
south, unless the thing being awakened can actually help solve the
problem, that extra wakeup does nothing but consume additional CPU time,
which is exactly what you don't want during a call_rcu() flood.
This commit therefore avoids doing anything if the corresponding
no-CBs callback kthread is going full tilt. Otherwise, if advancing
callbacks immediately might help and if the leaf rcu_node structure's
lock is immediately available, this commit invokes a new variant of
rcu_advance_cbs() that advances callbacks only if doing so won't require
awakening the grace-period kthread (not to be confused with any of the
no-CBs grace-period kthreads).
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
It might be hard to imagine having more than two billion callbacks
queued on a single CPU's ->cblist, but someone will do it sometime.
This commit therefore makes __call_rcu_nocb_wake() handle this situation
by upgrading local variable "len" from "int" to "long".
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, wake_nocb_gp_defer() simply stores whatever waketype was
passed in, which can result in a RCU_NOCB_WAKE_FORCE being downgraded
to RCU_NOCB_WAKE, which could in turn delay callback processing.
This commit therefore adds a check so that wake_nocb_gp_defer() only
updates ->nocb_defer_wakeup when the update increases the forcefulness,
thus avoiding downgrades.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The __call_rcu_nocb_wake() function and its predecessors set
->qlen_last_fqs_check to zero for the first callback and to LONG_MAX / 2
for forced reawakenings. The former can result in a too-quick reawakening
when there are many callbacks ready to invoke and the latter prevents a
second reawakening. This commit therefore sets ->qlen_last_fqs_check
to the current number of callbacks in both cases. While in the area,
this commit also moves both assignments under ->nocb_lock.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Historically, no-CBs CPUs allowed the scheduler-clock tick to be
unconditionally disabled on any transition to idle or nohz_full userspace
execution (see the rcu_needs_cpu() implementations). Unfortunately,
the checks used by rcu_needs_cpu() are defeated now that no-CBs CPUs
use ->cblist, which might make users of battery-powered devices rather
unhappy. This commit therefore adds explicit rcu_segcblist_is_offloaded()
checks to return to the historical energy-efficient semantics.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Some compilers complain that wait_gp_seq might be used uninitialized
in nocb_gp_wait(). This cannot actually happen because when wait_gp_seq
is uninitialized, needwait_gp must be false, which prevents wait_gp_seq
from being used. But this analysis is apparently beyond some compilers,
so this commit adds a bogus initialization of wait_gp_seq for the sole
purpose of suppressing the false-positive warning.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, rcu_pending() invokes rcu_segcblist_is_offloaded() even
in CONFIG_RCU_NOCB_CPU=n kernels, which cannot possibly be offloaded.
Given that rcu_pending() is on a fastpath, it makes sense to check for
CONFIG_RCU_NOCB_CPU=y before invoking rcu_segcblist_is_offloaded().
This commit therefore makes this change.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, rcu_core() invokes rcu_segcblist_is_offloaded() each time it
needs to know whether the current CPU is a no-CBs CPU. Given that it is
not possible to change the no-CBs status of a CPU after boot, and given
that it is not possible to even have no-CBs CPUs in CONFIG_RCU_NOCB_CPU=n
kernels, this repeated runtime invocation wastes CPU. This commit
therefore created a const on-stack variable to allow this check to be
done only once per rcu_core() invocation.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, rcu_do_batch() invokes rcu_segcblist_is_offloaded() each time
it needs to know whether the current CPU is a no-CBs CPU. Given that it
is not possible to change the no-CBs status of a CPU after boot, and given
that it is not possible to even have no-CBs CPUs in CONFIG_RCU_NOCB_CPU=n
kernels, this per-callback invocation wastes CPU. This commit therefore
created a const on-stack variable to allow this check to be done only
once per rcu_do_batch() invocation.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit removes the obsolete nocb_q_count and nocb_q_count_lazy
fields, also removing rcu_get_n_cbs_nocb_cpu(), adjusting
rcu_get_n_cbs_cpu(), and making rcutree_migrate_callbacks() once again
disable the ->cblist fields of offline CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently the RCU callbacks for no-CBs CPUs are queued on a series of
ad-hoc linked lists, which means that these callbacks cannot benefit
from "drive-by" grace periods, thus suffering needless delays prior
to invocation. In addition, the no-CBs grace-period kthreads first
wait for callbacks to appear and later wait for a new grace period,
which means that callbacks appearing during a grace-period wait can
be delayed. These delays increase memory footprint, and could even
result in an out-of-memory condition.
This commit therefore enqueues RCU callbacks from no-CBs CPUs on the
rcu_segcblist structure that is already used by non-no-CBs CPUs. It also
restructures the no-CBs grace-period kthread to be checking for incoming
callbacks while waiting for grace periods. Also, instead of waiting
for a new grace period, it waits for the closest grace period that will
cause some of the callbacks to be safe to invoke. All of these changes
reduce callback latency and thus the number of outstanding callbacks,
in turn reducing the probability of an out-of-memory condition.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
As a first step towards making no-CBs CPUs use the ->cblist, this commit
leaves the ->cblist enabled for these CPUs. The main reason to make
no-CBs CPUs use ->cblist is to take advantage of callback numbering,
which will reduce the effects of missed grace periods which in turn will
reduce forward-progress problems for no-CBs CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, rcu_segcblist_empty() assumes that the callback list is not
being changed by other CPUs, but upcoming changes will require it to
operate locklessly. This commit therefore adds the needed READ_ONCE()
call, along with the WRITE_ONCE() calls when updating the callback list's
->head field.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, rcu_segcblist_restempty() assumes that the callback list
is not being changed by other CPUs, but upcoming changes will require
it to operate locklessly. This commit therefore adds the needed
READ_ONCE() calls, along with the WRITE_ONCE() calls when updating
the callback list.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The idea behind the checks for extended quiescent states at the end of
__call_rcu_nocb() is to handle cases where call_rcu() is invoked directly
from within an extended quiescent state, for example, from the idle loop.
However, this will result in a timer-mediated deferred wakeup, which
will cause the needed wakeup to happen within a jiffy or thereabouts.
There should be no forward-progress concerns, and if there are, the proper
response is to exit the extended quiescent state while executing the
endless blast of call_rcu() invocations, for example, using RCU_NONIDLE().
Given the more realistic case of an isolated call_rcu() invocation, there
should be no problem.
This commit therefore removes the checks for invoking call_rcu() within
an extended quiescent state for on no-CBs CPUs.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
In theory, a timer is used to defer wakeups of no-CBs grace-period
kthreads when the wakeup cannot be done safely directly from the
call_rcu(). In practice, the one-jiffy delay is not always consistent
with timely callback invocation under heavy call_rcu() loads. Therefore,
there are a number of checks for a pending deferred wakeup, including
from the scheduling-clock interrupt. Unfortunately, this check follows
the rcu_nohz_full_cpu() early exit, which renders it useless on such CPUs.
This commit therefore moves the check for the pending deferred no-CB
wakeup to precede the rcu_nohz_full_cpu() early exit.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because rcutree_migrate_callbacks() is invoked infrequently and because
an exact snapshot of the grace-period state might save some callbacks a
second trip through a grace period, this function has used the root
rcu_node structure. However, this safe-second-trip optimization
happens only if rcutree_migrate_callbacks() races with grace-period
initialization, so it is not worth the added mental load. This commit
therefore makes rcutree_migrate_callbacks() start with the leaf rcu_node
structures, as is done elsewhere.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit is a preparatory patch for offloaded callbacks using the
same ->cblist structure used by non-offloaded callbacks. It therefore
adds rcu_segcblist_is_offloaded() calls where they will be needed when
!rcu_segcblist_is_enabled() no longer flags the offloaded case. It also
adds checks in rcu_do_batch() to ensure that there are no missed checks:
Currently, it should not be possible for offloaded execution to reach
rcu_do_batch(), though this will change later in this series.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
RCU callback processing currently uses rcu_is_nocb_cpu() to determine
whether or not the current CPU's callbacks are to be offloaded.
This works, but it is not so good for cache locality. Plus use of
->cblist for offloaded callbacks will greatly increase the frequency
of these checks. This commit therefore adds a ->offloaded flag to the
rcu_segcblist structure to provide a more flexible and cache-friendly
means of checking for callback offloading.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
NULLing the RCU_NEXT_TAIL pointer was a clever way to save a byte, but
forward-progress considerations would require that this pointer be both
NULL and non-NULL, which, absent a quantum-computer port of the Linux
kernel, simply won't happen. This commit therefore creates as separate
->enabled flag to replace the current NULL checks.
[ paulmck: Add include files per 0day test robot and -next. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit causes the no-CBs grace-period/callback hierarchy to be
printed to the console when the dump_tree kernel boot parameter is set.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit changes the name of the rcu_nocb_leader_stride kernel
boot parameter to rcu_nocb_gp_stride in order to account for the new
distinction between callback and grace-period no-CBs kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The nocb_cb_wait() function traces a "FollowerSleep" trace_rcu_nocb_wake()
event, which never was documented and is now misleading. This commit
therefore changes "FollowerSleep" to "CBSleep", documents this, and
updates the documentation for "Sleep" as well.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit renames rdp_leader to rdp_gp in order to account for the
new distinction between callback and grace-period no-CBs kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adjusts naming to account for the new distinction between
callback and grace-period no-CBs kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adjusts naming to account for the new distinction between
callback and grace-period no-CBs kthreads. While in the area, it also
updates local variables.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adjusts naming to account for the new distinction between
callback and grace-period no-CBs kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit adjusts naming to account for the new distinction between
callback and grace-period no-CBs kthreads.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Currently, there is one no-CBs rcuo kthread per CPU, and these kthreads
are divided into groups. The first rcuo kthread to come online in a
given group is that group's leader, and the leader both waits for grace
periods and invokes its CPU's callbacks. The non-leader rcuo kthreads
only invoke callbacks.
This works well in the real-time/embedded environments for which it was
intended because such environments tend not to generate all that many
callbacks. However, given huge floods of callbacks, it is possible for
the leader kthread to be stuck invoking callbacks while its followers
wait helplessly while their callbacks pile up. This is a good recipe
for an OOM, and rcutorture's new callback-flood capability does generate
such OOMs.
One strategy would be to wait until such OOMs start happening in
production, but similar OOMs have in fact happened starting in 2018.
It would therefore be wise to take a more proactive approach.
This commit therefore features per-CPU rcuo kthreads that do nothing
but invoke callbacks. Instead of having one of these kthreads act as
leader, each group has a separate rcog kthread that handles grace periods
for its group. Because these rcuog kthreads do not invoke callbacks,
callback floods on one CPU no longer block callbacks from reaching the
rcuc callback-invocation kthreads on other CPUs.
This change does introduce additional kthreads, however:
1. The number of additional kthreads is about the square root of
the number of CPUs, so that a 4096-CPU system would have only
about 64 additional kthreads. Note that recent changes
decreased the number of rcuo kthreads by a factor of two
(CONFIG_PREEMPT=n) or even three (CONFIG_PREEMPT=y), so
this still represents a significant improvement on most systems.
2. The leading "rcuo" of the rcuog kthreads should allow existing
scripting to affinity these additional kthreads as needed, the
same as for the rcuop and rcuos kthreads. (There are no longer
any rcuob kthreads.)
3. A state-machine approach was considered and rejected. Although
this would allow the rcuo kthreads to continue their dual
leader/follower roles, it complicates callback invocation
and makes it more difficult to consolidate rcuo callback
invocation with existing softirq callback invocation.
The introduction of rcuog kthreads should thus be acceptable.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit simply rewords comments to prepare for leader nocb kthreads
doing only grace-period work and callback shuffling. This will mean
the addition of replacement kthreads to invoke callbacks. The "leader"
and "follower" thus become less meaningful, so the commit changes no-CB
comments with these strings to "GP" and "CB", respectively. (Give or
take the usual grammatical transformations.)
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
This commit simply renames rcu_data fields to prepare for leader
nocb kthreads doing only grace-period work and callback shuffling.
This will mean the addition of replacement kthreads to invoke callbacks.
The "leader" and "follower" thus become less meaningful, so the commit
changes no-CB fields with these strings to "gp" and "cb", respectively.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Expose kernel's BTF under the name vmlinux to be more uniform with using
kernel module names as file names in the future.
Fixes: 341dfcf8d7 ("btf: expose BTF info through sysfs")
Suggested-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Make .BTF section allocated and expose its contents through sysfs.
/sys/kernel/btf directory is created to contain all the BTFs present
inside kernel. Currently there is only kernel's main BTF, represented as
/sys/kernel/btf/kernel file. Once kernel modules' BTFs are supported,
each module will expose its BTF as /sys/kernel/btf/<module-name> file.
Current approach relies on a few pieces coming together:
1. pahole is used to take almost final vmlinux image (modulo .BTF and
kallsyms) and generate .BTF section by converting DWARF info into
BTF. This section is not allocated and not mapped to any segment,
though, so is not yet accessible from inside kernel at runtime.
2. objcopy dumps .BTF contents into binary file and subsequently
convert binary file into linkable object file with automatically
generated symbols _binary__btf_kernel_bin_start and
_binary__btf_kernel_bin_end, pointing to start and end, respectively,
of BTF raw data.
3. final vmlinux image is generated by linking this object file (and
kallsyms, if necessary). sysfs_btf.c then creates
/sys/kernel/btf/kernel file and exposes embedded BTF contents through
it. This allows, e.g., libbpf and bpftool access BTF info at
well-known location, without resorting to searching for vmlinux image
on disk (location of which is not standardized and vmlinux image
might not be even available in some scenarios, e.g., inside qemu
during testing).
Alternative approach using .incbin assembler directive to embed BTF
contents directly was attempted but didn't work, because sysfs_proc.o is
not re-compiled during link-vmlinux.sh stage. This is required, though,
to update embedded BTF data (initially empty data is embedded, then
pahole generates BTF info and we need to regenerate sysfs_btf.o with
updated contents, but it's too late at that point).
If BTF couldn't be generated due to missing or too old pahole,
sysfs_btf.c handles that gracefully by detecting that
_binary__btf_kernel_bin_start (weak symbol) is 0 and not creating
/sys/kernel/btf at all.
v2->v3:
- added Documentation/ABI/testing/sysfs-kernel-btf (Greg K-H);
- created proper kobject (btf_kobj) for btf directory (Greg K-H);
- undo v2 change of reusing vmlinux, as it causes extra kallsyms pass
due to initially missing __binary__btf_kernel_bin_{start/end} symbols;
v1->v2:
- allow kallsyms stage to re-use vmlinux generated by gen_btf();
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
This commit fixes a spelling mistake in file tree_exp.h.
Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because rcu_expedited_nesting is initialized to 1 and not decremented
until just before init is spawned, rcu_expedited_nesting is guaranteed
to be non-zero whenever rcu_scheduler_active == RCU_SCHEDULER_INIT.
This commit therefore removes this redundant "if" equality test.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Scheduling-clock interrupts can arrive late in the CPU-offline process,
after idle entry and the subsequent call to cpuhp_report_idle_dead().
Once execution passes the call to rcu_report_dead(), RCU is ignoring
the CPU, which results in lockdep complaints when the interrupt handler
uses RCU:
------------------------------------------------------------------------
=============================
WARNING: suspicious RCU usage
5.2.0-rc1+ #681 Not tainted
-----------------------------
kernel/sched/fair.c:9542 suspicious rcu_dereference_check() usage!
other info that might help us debug this:
RCU used illegally from offline CPU!
rcu_scheduler_active = 2, debug_locks = 1
no locks held by swapper/5/0.
stack backtrace:
CPU: 5 PID: 0 Comm: swapper/5 Not tainted 5.2.0-rc1+ #681
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Bochs 01/01/2011
Call Trace:
<IRQ>
dump_stack+0x5e/0x8b
trigger_load_balance+0xa8/0x390
? tick_sched_do_timer+0x60/0x60
update_process_times+0x3b/0x50
tick_sched_handle+0x2f/0x40
tick_sched_timer+0x32/0x70
__hrtimer_run_queues+0xd3/0x3b0
hrtimer_interrupt+0x11d/0x270
? sched_clock_local+0xc/0x74
smp_apic_timer_interrupt+0x79/0x200
apic_timer_interrupt+0xf/0x20
</IRQ>
RIP: 0010:delay_tsc+0x22/0x50
Code: ff 0f 1f 80 00 00 00 00 65 44 8b 05 18 a7 11 48 0f ae e8 0f 31 48 89 d6 48 c1 e6 20 48 09 c6 eb 0e f3 90 65 8b 05 fe a6 11 48 <41> 39 c0 75 18 0f ae e8 0f 31 48 c1 e2 20 48 09 c2 48 89 d0 48 29
RSP: 0000:ffff8f92c0157ed0 EFLAGS: 00000212 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000005 RBX: ffff8c861f356400 RCX: ffff8f92c0157e64
RDX: 000000321214c8cc RSI: 00000032120daa7f RDI: 0000000000260f15
RBP: 0000000000000005 R08: 0000000000000005 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000000000
R13: 0000000000000000 R14: ffff8c861ee18000 R15: ffff8c861ee18000
cpuhp_report_idle_dead+0x31/0x60
do_idle+0x1d5/0x200
? _raw_spin_unlock_irqrestore+0x2d/0x40
cpu_startup_entry+0x14/0x20
start_secondary+0x151/0x170
secondary_startup_64+0xa4/0xb0
------------------------------------------------------------------------
This happens rarely, but can be forced by happen more often by
placing delays in cpuhp_report_idle_dead() following the call to
rcu_report_dead(). With this in place, the following rcutorture
scenario reproduces the problem within a few minutes:
tools/testing/selftests/rcutorture/bin/kvm.sh --cpus 8 --duration 5 --kconfig "CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_PROVE_LOCKING=y" --configs "TREE04"
This commit uses the crude but effective expedient of moving the disabling
of interrupts within the idle loop to precede the cpu_is_offline()
check. It also invokes tick_nohz_idle_stop_tick() instead of
tick_nohz_idle_stop_tick_protected() to shut off the scheduling-clock
interrupt.
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
[ paulmck: Revert tick_nohz_idle_stop_tick_protected() removal, new callers. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
If CONFIG_ARCH_TASK_STRUCT_ALLOCATOR is set task_struct_whitelist is
never called, and thus generates a compiler warning.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lkml.kernel.org/r/20190812065524.19959-5-hch@lst.de
Signed-off-by: Tony Luck <tony.luck@intel.com>
Enabling WARN_DOUBLE_CLOCK in /sys/kernel/debug/sched_features causes
warning to fire in update_rq_clock. This seems to be caused by onlining
a new fair sched group not using the rq lock wrappers.
[] rq->clock_update_flags & RQCF_UPDATED
[] WARNING: CPU: 5 PID: 54385 at kernel/sched/core.c:210 update_rq_clock+0xec/0x150
[] Call Trace:
[] online_fair_sched_group+0x53/0x100
[] cpu_cgroup_css_online+0x16/0x20
[] online_css+0x1c/0x60
[] cgroup_apply_control_enable+0x231/0x3b0
[] cgroup_mkdir+0x41b/0x530
[] kernfs_iop_mkdir+0x61/0xa0
[] vfs_mkdir+0x108/0x1a0
[] do_mkdirat+0x77/0xe0
[] do_syscall_64+0x55/0x1d0
[] entry_SYSCALL_64_after_hwframe+0x44/0xa9
Using the wrappers in online_fair_sched_group instead of the raw locking
removes this warning.
[ tglx: Use rq_*lock_irq() ]
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20190801133749.11033-1-pauld@redhat.com
Pull scheduler fixes from Thomas Gleixner:
"Three fixlets for the scheduler:
- Avoid double bandwidth accounting in the push & pull code
- Use a sane FIFO priority for the Pressure Stall Information (PSI)
thread.
- Avoid permission checks when setting the scheduler params for the
PSI thread"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/psi: Do not require setsched permission from the trigger creator
sched/psi: Reduce psimon FIFO priority
sched/deadline: Fix double accounting of rq/running bw in push & pull
All the way back to introducing dma_common_mmap we've defaulted to mark
the pages as uncached. But this is wrong for DMA coherent devices.
Later on DMA_ATTR_WRITE_COMBINE also got incorrect treatment as that
flag is only treated special on the alloc side for non-coherent devices.
Introduce a new dma_pgprot helper that deals with the check for coherent
devices so that only the remapping cases ever reach arch_dma_mmap_pgprot
and we thus ensure no aliasing of page attributes happens, which makes
the powerpc version of arch_dma_mmap_pgprot obsolete and simplifies the
remaining ones.
Note that this means arch_dma_mmap_pgprot is a bit misnamed now, but
we'll phase it out soon.
Fixes: 64ccc9c033 ("common: dma-mapping: add support for generic dma_mmap_* calls")
Reported-by: Shawn Anastasio <shawn@anastas.io>
Reported-by: Gavin Li <git@thegavinli.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Catalin Marinas <catalin.marinas@arm.com> # arm64
The dma required_mask needs to reflect the actual addressing capabilities
needed to handle the whole system RAM. When truncated down to the bus
addressing capabilities dma_addressing_limited() will incorrectly signal
no limitations for devices which are restricted by the bus_dma_mask.
Fixes: b4ebe60632 (dma-direct: implement complete bus_dma_mask handling)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Tested-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The new DMA_ATTR_NO_KERNEL_MAPPING needs to actually assign
a dma_addr to work. Also skip it if the architecture needs
forced decryption handling, as that needs a kernel virtual
address.
Fixes: d98849aff8 (dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code)
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Lucas Stach <l.stach@pengutronix.de>
To avoid reducing the frequency of a CPU prematurely, we skip reducing
the frequency if the CPU had been busy recently.
This should not be done when the limits of the policy are changed, for
example due to thermal throttling. We should always get the frequency
within the new limits as soon as possible.
Trying to fix this by using only one flag, i.e. need_freq_update, can
lead to a race condition where the flag gets cleared without forcing us
to change the frequency at least once. And so this patch introduces
another flag to avoid that race condition.
Fixes: ecd2884291 ("cpufreq: schedutil: Don't set next_freq to UINT_MAX")
Cc: v4.18+ <stable@vger.kernel.org> # v4.18+
Reported-by: Doug Smythies <dsmythies@telus.net>
Tested-by: Doug Smythies <dsmythies@telus.net>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After commit ac9eafbe93 ("ACPI: PM: s2idle: Execute LPS0 _DSM
functions with suspended devices"), a NULL pointer may be dereferenced
if suspend-to-idle is attempted on a platform without "traditional"
suspend support due to invalid fall-through in
platform_suspend_prepare_noirq().
Fix that and while at it add missing braces in platform_resume_noirq().
Fixes: ac9eafbe93 ("ACPI: PM: s2idle: Execute LPS0 _DSM functions with suspended devices")
Reported-by: Marek Szyprowski <m.szyprowski@samsung.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
This commit adds RCU-reader checks to list_for_each_entry_rcu() and
hlist_for_each_entry_rcu(). These checks are optional, and are indicated
by a lockdep expression passed to a new optional argument to these two
macros. If this optional lockdep expression is omitted, these two macros
act as before, checking for an RCU read-side critical section.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Update to eliminate return within macro and update comment. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
sme_active() is an x86-specific function so it's better not to call it from
generic code. Christoph Hellwig mentioned that "There is no reason why we
should have a special debug printk just for one specific reason why there
is a requirement for a large DMA mask.", so just remove dma_check_mask().
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190806044919.10622-4-bauerman@linux.ibm.com
sme_active() is an x86-specific function so it's better not to call it from
generic code.
There's no need to mention which memory encryption feature is active, so
just use a more generic message. Besides, other architectures will have
different names for similar technology.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Tom Lendacky <thomas.lendacky@amd.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20190806044919.10622-3-bauerman@linux.ibm.com
Exercising CPU hotplug on a 5.2 kernel with recent padata fixes from
cryptodev-2.6.git in an 8-CPU kvm guest...
# modprobe tcrypt alg="pcrypt(rfc4106(gcm(aes)))" type=3
# echo 0 > /sys/devices/system/cpu/cpu1/online
# echo c > /sys/kernel/pcrypt/pencrypt/parallel_cpumask
# modprobe tcrypt mode=215
...caused the following crash:
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor read access in kernel mode
#PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
Oops: 0000 [#1] SMP PTI
CPU: 2 PID: 134 Comm: kworker/2:2 Not tainted 5.2.0-padata-base+ #7
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.12.0-<snip>
Workqueue: pencrypt padata_parallel_worker
RIP: 0010:padata_reorder+0xcb/0x180
...
Call Trace:
padata_do_serial+0x57/0x60
pcrypt_aead_enc+0x3a/0x50 [pcrypt]
padata_parallel_worker+0x9b/0xe0
process_one_work+0x1b5/0x3f0
worker_thread+0x4a/0x3c0
...
In padata_alloc_pd, pd->cpu is set using the user-supplied cpumask
instead of the effective cpumask, and in this case cpumask_first picked
an offline CPU.
The offline CPU's reorder->list.next is NULL in padata_reorder because
the list wasn't initialized in padata_init_pqueues, which only operates
on CPUs in the effective mask.
Fix by using the effective mask in padata_alloc_pd.
Fixes: 6fc4dbcf02 ("padata: Replace delayed timer with immediate workqueue in padata_reorder")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
According to Section 3.5 of the "Intel Low Power S0 Idle" document [1],
Function 5 of the LPS0 _DSM is expected to be invoked when the system
configuration matches the criteria for entering the target low-power
state of the platform. In particular, this means that all devices
should be suspended and in low-power states already when that function
is invoked.
This is not the case currently, however, because Function 5 of the
LPS0 _DSM is invoked by it before the "noirq" phase of device suspend,
which means that some devices may not have been put into low-power
states yet at that point. That is a consequence of the previous
design of the suspend-to-idle flow that allowed the "noirq" phase of
device suspend and the "noirq" phase of device resume to be carried
out for multiple times while "suspended" (if any spurious wakeup
events were detected) and the point of the LPS0 _DSM Function 5
invocation was chosen so as to call it (and LPS0 _DSM Function 6
analogously) once per suspend-resume cycle (regardless of how many
times the "noirq" phases of device suspend and resume were carried
out while "suspended").
Now that the suspend-to-idle flow has been redesigned to carry out
the "noirq" phases of device suspend and resume once in each cycle,
the code can be reordered to follow the specification that it is
based on more closely.
For this purpose, add ->prepare_late and ->restore_early platform
callbacks for suspend-to-idle, to be executed, respectively, after
the "noirq" phase of suspending devices and before the "noirq"
phase of resuming them and make ACPI use them for the invocation
of LPS0 _DSM functions as appropriate.
While at it, move the LPS0 entry requirements check to be made
before invoking Functions 3 and 5 of the LPS0 _DSM (also once
per cycle) as follows from the specification [1].
Link: https://uefi.org/sites/default/files/resources/Intel_ACPI_Low_Power_S0_Idle.pdf # [1]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
scale_irq_capacity() call in schedutil_cpu_util() does
util *= (max - irq)
util /= max
But the comment says
util *= (1 - irq)
util /= max
Fix the comment to match what the scaling function does.
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Acked-by: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "Rafael J . Wysocki" <rjw@rjwysocki.net>
Link: https://lkml.kernel.org/r/20190802104628.8410-1-qais.yousef@arm.com
Avoid the RETRY_TASK case in the pick_next_task() slow path.
By doing the put_prev_task() early, we get the rt/deadline pull done,
and by testing rq->nr_running we know if we need newidle_balance().
This then gives a stable state to pick a task from.
Since the fast-path is fair only; it means the other classes will
always have pick_next_task(.prev=NULL, .rf=NULL) and we can simplify.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Link: https://lkml.kernel.org/r/aa34d24b36547139248f32a30138791ac6c02bd6.1559129225.git.vpillai@digitalocean.com
Currently the pick_next_task() loop is convoluted and ugly because of
how it can drop the rq->lock and needs to restart the picking.
For the RT/Deadline classes, it is put_prev_task() where we do
balancing, and we could do this before the picking loop. Make this
possible.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Link: https://lkml.kernel.org/r/e4519f6850477ab7f3d257062796e6425ee4ba7c.1559129225.git.vpillai@digitalocean.com
For pick_next_task_fair() it is the newidle balance that requires
dropping the rq->lock; provided we do put_prev_task() early, we can
also detect the condition for doing newidle early.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Link: https://lkml.kernel.org/r/9e3eb1859b946f03d7e500453a885725b68957ba.1559129225.git.vpillai@digitalocean.com
In preparation of further separating pick_next_task() and
set_curr_task() we have to pass the actual task into it, while there,
rename the thing to better pair with put_prev_task().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Link: https://lkml.kernel.org/r/a96d1bcdd716db4a4c5da2fece647a1456c0ed78.1559129225.git.vpillai@digitalocean.com
The CPU hotplug task selection is the only place where we used
put_prev_task() on a task that is not current. While looking at that,
it occured to me that we can simplify all that by by using a custom
pick loop.
Since we don't need to put current, we can do away with the fake task
too.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Because pick_next_task() implies set_curr_task() and some of the
details haven't mattered too much, some of what _should_ be in
set_curr_task() ended up in pick_next_task, correct this.
This prepares the way for a pick_next_task() variant that does not
affect the current state; allowing remote picking.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Aaron Lu <aaron.lwe@gmail.com>
Cc: Valentin Schneider <valentin.schneider@arm.com>
Cc: mingo@kernel.org
Cc: Phil Auld <pauld@redhat.com>
Cc: Julien Desfossez <jdesfossez@digitalocean.com>
Cc: Nishanth Aravamudan <naravamudan@digitalocean.com>
Link: https://lkml.kernel.org/r/38c61d5240553e043c27c5e00b9dd0d184dd6081.1559129225.git.vpillai@digitalocean.com
It has been observed, that highly-threaded, non-cpu-bound applications
running under cpu.cfs_quota_us constraints can hit a high percentage of
periods throttled while simultaneously not consuming the allocated
amount of quota. This use case is typical of user-interactive non-cpu
bound applications, such as those running in kubernetes or mesos when
run on multiple cpu cores.
This has been root caused to cpu-local run queue being allocated per cpu
bandwidth slices, and then not fully using that slice within the period.
At which point the slice and quota expires. This expiration of unused
slice results in applications not being able to utilize the quota for
which they are allocated.
The non-expiration of per-cpu slices was recently fixed by
'commit 512ac999d2 ("sched/fair: Fix bandwidth timer clock drift
condition")'. Prior to that it appears that this had been broken since
at least 'commit 51f2176d74 ("sched/fair: Fix unlocked reads of some
cfs_b->quota/period")' which was introduced in v3.16-rc1 in 2014. That
added the following conditional which resulted in slices never being
expired.
if (cfs_rq->runtime_expires != cfs_b->runtime_expires) {
/* extend local deadline, drift is bounded above by 2 ticks */
cfs_rq->runtime_expires += TICK_NSEC;
Because this was broken for nearly 5 years, and has recently been fixed
and is now being noticed by many users running kubernetes
(https://github.com/kubernetes/kubernetes/issues/67577) it is my opinion
that the mechanisms around expiring runtime should be removed
altogether.
This allows quota already allocated to per-cpu run-queues to live longer
than the period boundary. This allows threads on runqueues that do not
use much CPU to continue to use their remaining slice over a longer
period of time than cpu.cfs_period_us. However, this helps prevent the
above condition of hitting throttling while also not fully utilizing
your cpu quota.
This theoretically allows a machine to use slightly more than its
allotted quota in some periods. This overflow would be bounded by the
remaining quota left on each per-cpu runqueueu. This is typically no
more than min_cfs_rq_runtime=1ms per cpu. For CPU bound tasks this will
change nothing, as they should theoretically fully utilize all of their
quota in each period. For user-interactive tasks as described above this
provides a much better user/application experience as their cpu
utilization will more closely match the amount they requested when they
hit throttling. This means that cpu limits no longer strictly apply per
period for non-cpu bound applications, but that they are still accurate
over longer timeframes.
This greatly improves performance of high-thread-count, non-cpu bound
applications with low cfs_quota_us allocation on high-core-count
machines. In the case of an artificial testcase (10ms/100ms of quota on
80 CPU machine), this commit resulted in almost 30x performance
improvement, while still maintaining correct cpu quota restrictions.
That testcase is available at https://github.com/indeedeng/fibtest.
Fixes: 512ac999d2 ("sched/fair: Fix bandwidth timer clock drift condition")
Signed-off-by: Dave Chiluk <chiluk+linux@indeed.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Phil Auld <pauld@redhat.com>
Reviewed-by: Ben Segall <bsegall@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Hammond <jhammond@indeed.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Kyle Anderson <kwa@yelp.com>
Cc: Gabriel Munos <gmunoz@netflix.com>
Cc: Peter Oskolkov <posk@posk.io>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Brendan Gregg <bgregg@netflix.com>
Link: https://lkml.kernel.org/r/1563900266-19734-2-git-send-email-chiluk+linux@indeed.com
The current active_mm reference counting is confusing and sub-optimal.
Rewrite the code to explicitly consider the 4 separate cases:
user -> user
When switching between two user tasks, all we need to consider
is switch_mm().
user -> kernel
When switching from a user task to a kernel task (which
doesn't have an associated mm) we retain the last mm in our
active_mm. Increment a reference count on active_mm.
kernel -> kernel
When switching between kernel threads, all we need to do is
pass along the active_mm reference.
kernel -> user
When switching between a kernel and user task, we must switch
from the last active_mm to the next mm, hoping of course that
these are the same. Decrement a reference on the active_mm.
The code keeps a different order, because as you'll note, both 'to
user' cases require switch_mm().
And where the old code would increment/decrement for the 'kernel ->
kernel' case, the new code observes this is a neutral operation and
avoids touching the reference count.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Rik van Riel <riel@surriel.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: luto@kernel.org
A rather embarrasing mistake had us call sched_setscheduler() before
initializing the parameters passed to it.
Fixes: 1a763fd7c6 ("rcu/tree: Call setschedule() gp ktread to SCHED_FIFO outside of atomic region")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
The patch moving bits into mutex.c was a little too much; by also
moving struct mutex_waiter a few less common CONFIGs would no longer
build.
Fixes: 5f35d5a66b ("locking/mutex: Make __mutex_owner static to mutex.c")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Since commit c66d4bd110 ("genirq/affinity: Add new callback for
(re)calculating interrupt sets"), irq_create_affinity_masks() returns
NULL in case of single vector. This change has caused regression on some
drivers, such as lpfc.
The problem is that single vector requests can happen in some generic cases:
1) kdump kernel
2) irq vectors resource is close to exhaustion.
If in that situation the affinity mask for a single vector is not created,
every caller has to handle the special case.
There is no reason why the mask cannot be created, so remove the check for
a single vector and create the mask.
Fixes: c66d4bd110 ("genirq/affinity: Add new callback for (re)calculating interrupt sets")
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190805011906.5020-1-ming.lei@redhat.com
Instead of using its own logic for k-/vmalloc rely on
kvmalloc which is actually doing quite the same.
Signed-off-by: Marc Koderer <marc@koderer.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Booting a large arm64 server (HiSi D05) leads to the following
shouting at boot time:
[ 20.722132] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
[ 20.730851] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
[ 20.739560] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
[ 20.748267] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
[ 20.756975] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
[ 20.765683] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
[ 20.774391] debugfs: File 'irqchip@(____ptrval____)-3' in directory 'domains' already present!
and many more... Evidently, we expect something a bit more informative
than ____ptrval____, and certainly we want all of our domains, not just
the first one.
For that, turn the %p used to generate the fwnode name into something
that won't be repainted (%pa). Given that we've now fixed all users to
pass a pointer to a PA, it will actually do the right thing.
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Pull networking fixes from David Miller:
"Yeah I should have sent a pull request last week, so there is a lot
more here than usual:
1) Fix memory leak in ebtables compat code, from Wenwen Wang.
2) Several kTLS bug fixes from Jakub Kicinski (circular close on
disconnect etc.)
3) Force slave speed check on link state recovery in bonding 802.3ad
mode, from Thomas Falcon.
4) Clear RX descriptor bits before assigning buffers to them in
stmmac, from Jose Abreu.
5) Several missing of_node_put() calls, mostly wrt. for_each_*() OF
loops, from Nishka Dasgupta.
6) Double kfree_skb() in peak_usb can driver, from Stephane Grosjean.
7) Need to hold sock across skb->destructor invocation, from Cong
Wang.
8) IP header length needs to be validated in ipip tunnel xmit, from
Haishuang Yan.
9) Use after free in ip6 tunnel driver, also from Haishuang Yan.
10) Do not use MSI interrupts on r8169 chips before RTL8168d, from
Heiner Kallweit.
11) Upon bridge device init failure, we need to delete the local fdb.
From Nikolay Aleksandrov.
12) Handle erros from of_get_mac_address() properly in stmmac, from
Martin Blumenstingl.
13) Handle concurrent rename vs. dump in netfilter ipset, from Jozsef
Kadlecsik.
14) Setting NETIF_F_LLTX on mac80211 causes complete breakage with
some devices, so revert. From Johannes Berg.
15) Fix deadlock in rxrpc, from David Howells.
16) Fix Kconfig deps of enetc driver, we must have PHYLIB. From Yue
Haibing.
17) Fix mvpp2 crash on module removal, from Matteo Croce.
18) Fix race in genphy_update_link, from Heiner Kallweit.
19) bpf_xdp_adjust_head() stopped working with generic XDP when we
fixes generic XDP to support stacked devices properly, fix from
Jesper Dangaard Brouer.
20) Unbalanced RCU locking in rt6_update_exception_stamp_rt(), from
David Ahern.
21) Several memory leaks in new sja1105 driver, from Vladimir Oltean"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (214 commits)
net: dsa: sja1105: Fix memory leak on meta state machine error path
net: dsa: sja1105: Fix memory leak on meta state machine normal path
net: dsa: sja1105: Really fix panic on unregistering PTP clock
net: dsa: sja1105: Use the LOCKEDS bit for SJA1105 E/T as well
net: dsa: sja1105: Fix broken learning with vlan_filtering disabled
net: dsa: qca8k: Add of_node_put() in qca8k_setup_mdio_bus()
net: sched: sample: allow accessing psample_group with rtnl
net: sched: police: allow accessing police->params with rtnl
net: hisilicon: Fix dma_map_single failed on arm64
net: hisilicon: fix hip04-xmit never return TX_BUSY
net: hisilicon: make hip04_tx_reclaim non-reentrant
tc-testing: updated vlan action tests with batch create/delete
net sched: update vlan action for batched events operations
net: stmmac: tc: Do not return a fragment entry
net: stmmac: Fix issues when number of Queues >= 4
net: stmmac: xgmac: Fix XGMAC selftests
be2net: disable bh with spin_lock in be_process_mcc
net: cxgb3_main: Fix a resource leak in a error path in 'init_one()'
net: ethernet: sun4i-emac: Support phy-handle property for finding PHYs
net: bridge: move default pvid init/deinit to NETDEV_REGISTER/UNREGISTER
...
It is not desirable to relax the ABI to allow tagged user addresses into
the kernel indiscriminately. This patch introduces a prctl() interface
for enabling or disabling the tagged ABI with a global sysctl control
for preventing applications from enabling the relaxed ABI (meant for
testing user-space prctl() return error checking without reconfiguring
the kernel). The ABI properties are inherited by threads of the same
application and fork()'ed children but cleared on execve(). A Kconfig
option allows the overall disabling of the relaxed ABI.
The PR_SET_TAGGED_ADDR_CTRL will be expanded in the future to handle
MTE-specific settings like imprecise vs precise exceptions.
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Signed-off-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Will Deacon <will@kernel.org>
When a process creates a new trigger by writing into /proc/pressure/*
files, permissions to write such a file should be used to determine whether
the process is allowed to do so or not. Current implementation would also
require such a process to have setsched capability. Setting of psi trigger
thread's scheduling policy is an implementation detail and should not be
exposed to the user level. Remove the permission check by using _nocheck
version of the function.
Suggested-by: Nick Kralevich <nnk@google.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: lizefan@huawei.com
Cc: mingo@redhat.com
Cc: akpm@linux-foundation.org
Cc: kernel-team@android.com
Cc: dennisszhou@gmail.com
Cc: dennis@kernel.org
Cc: hannes@cmpxchg.org
Cc: axboe@kernel.dk
Link: https://lkml.kernel.org/r/20190730013310.162367-1-surenb@google.com
PSI defaults to a FIFO-99 thread, reduce this to FIFO-1.
FIFO-99 is the very highest priority available to SCHED_FIFO and
it not a suitable default; it would indicate the psi work is the
most important work on the machine.
Since Real-Time tasks will have pre-allocated memory and locked it in
place, Real-Time tasks do not care about PSI. All it needs is to be
above OTHER.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Tested-by: Suren Baghdasaryan <surenb@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
__mutex_owner() should only be used by the mutex api's.
So, to put this restiction let's move the __mutex_owner()
function definition from linux/mutex.h to mutex.c file.
There exist functions that uses __mutex_owner() like
mutex_is_locked() and mutex_trylock_recursive(), So
to keep legacy thing intact move them as well and
export them.
Move mutex_waiter structure also to keep it private to the
file.
Signed-off-by: Mukesh Ojha <mojha@codeaurora.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: mingo@redhat.com
Cc: will@kernel.org
Link: https://lkml.kernel.org/r/1564585504-3543-1-git-send-email-mojha@codeaurora.org
Currently rwsems is the only locking primitive that lacks this
debug feature. Add it under CONFIG_DEBUG_RWSEMS and do the magic
checking in the locking fastpath (trylock) operation such that
we cover all cases. The unlocking part is pretty straightforward.
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: mingo@kernel.org
Cc: Davidlohr Bueso <dave@stgolabs.net>
Link: https://lkml.kernel.org/r/20190729044735.9632-1-dave@stgolabs.net
When the handoff bit is set by a writer, no other tasks other than
the setting writer itself is allowed to acquire the lock. If the
to-be-handoff'ed writer goes to sleep, there will be a wakeup latency
period where the lock is free, but no one can acquire it. That is less
than ideal.
To reduce that latency, the handoff writer will now optimistically spin
on the owner if it happens to be a on-cpu writer. It will spin until
it releases the lock and the to-be-handoff'ed writer can then acquire
the lock immediately without any delay. Of course, if the owner is not
a on-cpu writer, the to-be-handoff'ed writer will have to sleep anyway.
The optimistic spinning code is also modified to not stop spinning
when the handoff bit is set. This will prevent an occasional setting of
handoff bit from causing a bunch of optimistic spinners from entering
into the wait queue causing significant reduction in throughput.
On a 1-socket 22-core 44-thread Skylake system, the AIM7 shared_memory
workload was run with 7000 users. The throughput (jobs/min) of the
following kernels were as follows:
1) 5.2-rc6
- 8,092,486
2) 5.2-rc6 + tip's rwsem patches
- 7,567,568
3) 5.2-rc6 + tip's rwsem patches + this patch
- 7,954,545
Using perf-record(1), the %cpu time used by rwsem_down_write_slowpath(),
rwsem_down_write_failed() and their callees for the 3 kernels were 1.70%,
5.46% and 2.08% respectively.
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: x86@kernel.org
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: huang ying <huang.ying.caritas@gmail.com>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Link: https://lkml.kernel.org/r/20190625143913.24154-1-longman@redhat.com
IMA will use the module_signature format for append signatures, so export
the relevant definitions and factor out the code which verifies that the
appended signature trailer is valid.
Also, create a CONFIG_MODULE_SIG_FORMAT option so that IMA can select it
and be able to use mod_check_sig() without having to depend on either
CONFIG_MODULE_SIG or CONFIG_MODULES.
s390 duplicated the definition of struct module_signature so now they can
use the new <linux/module_signature.h> header instead.
Signed-off-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Acked-by: Jessica Yu <jeyu@kernel.org>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Userspace can get suspend stats from the suspend stats debugfs node.
Since debugfs doesn't have stable ABI, expose suspend stats in
sysfs under /sys/power/suspend_stats.
Signed-off-by: Kalesh Singh <kaleshsingh@google.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
memremap.c implements MM functionality for ZONE_DEVICE, so it really
should be in the mm/ directory, not the kernel/ one.
Link: http://lkml.kernel.org/r/20190722094143.18387-1-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The kernel-doc parser doesn't handle expressions with %foo*. Instead,
when an asterisk should be part of a constant, it uses an alternative
notation: `foo*`.
Link: http://lkml.kernel.org/r/7f18c2e0b5e39e6b7eb55ddeb043b8b260b49f2d.1563361575.git.mchehab+samsung@kernel.org
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This fixes a cascade of regressions that originally started with
the addition of the ia64 port, but only got fatal once we removed
most uses of block layer bounce buffering in Linux 4.18.
The reason is that while the original i386/PAE code that was the first
architecture that supported > 4GB of memory without an iommu decided to
leave bounce buffering to the subsystems, which in those days just mean
block and networking as no one else consumer arbitrary userspace memory.
Later with ia64, x86_64 and other ports we assumed that either an iommu
or something that fakes it up ("software IOTLB" in beautiful Intel
speak) is present and that subsystems can rely on that for dealing with
addressing limitations in devices. Except that the ARM LPAE scheme
that added larger physical address to 32-bit ARM did not follow that
scheme and thus only worked by chance and only for block and networking
I/O directly to highmem.
Long story, short fix - add swiotlb support to arm when build for LPAE
platforms, which actuallys turns out to be pretty trivial with the
modern dma-direct / swiotlb code to fix the Linux 4.18-ish regression.
-----BEGIN PGP SIGNATURE-----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=D6Uy
-----END PGP SIGNATURE-----
Merge tag 'arm-swiotlb-5.3' of git://git.infradead.org/users/hch/dma-mapping
Pull arm swiotlb support from Christoph Hellwig:
"This fixes a cascade of regressions that originally started with the
addition of the ia64 port, but only got fatal once we removed most
uses of block layer bounce buffering in Linux 4.18.
The reason is that while the original i386/PAE code that was the first
architecture that supported > 4GB of memory without an iommu decided
to leave bounce buffering to the subsystems, which in those days just
mean block and networking as no one else consumed arbitrary userspace
memory.
Later with ia64, x86_64 and other ports we assumed that either an
iommu or something that fakes it up ("software IOTLB" in beautiful
Intel speak) is present and that subsystems can rely on that for
dealing with addressing limitations in devices. Except that the ARM
LPAE scheme that added larger physical address to 32-bit ARM did not
follow that scheme and thus only worked by chance and only for block
and networking I/O directly to highmem.
Long story, short fix - add swiotlb support to arm when build for LPAE
platforms, which actuallys turns out to be pretty trivial with the
modern dma-direct / swiotlb code to fix the Linux 4.18-ish regression"
* tag 'arm-swiotlb-5.3' of git://git.infradead.org/users/hch/dma-mapping:
arm: use swiotlb for bounce buffering on LPAE configs
dma-mapping: check pfn validity in dma_common_{mmap,get_sgtable}
- fix alignment issues introduced in the CMA allocation rework
(Nicolin Chen)
-----BEGIN PGP SIGNATURE-----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=rM5q
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.3-3' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping regression fixes from Christoph Hellwig:
"Two related regression fixes for changes from this merge window to fix
alignment issues introduced in the CMA allocation rework (Nicolin
Chen)"
* tag 'dma-mapping-5.3-3' of git://git.infradead.org/users/hch/dma-mapping:
dma-contiguous: page-align the size in dma_free_contiguous()
dma-contiguous: do not overwrite align in dma_alloc_contiguous()
The more aggressive forward-progress tests can interfere with rcutorture
shutdown, resulting in false-positive diagnostics. This commit therefore
ends any such tests 30 seconds prior to shutdown.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
It is possible that the rcuperf kernel test runs concurrently with init
starting up. During this time, the system is running all grace periods
as expedited. However, rcuperf can also be run for normal GP tests.
Right now, it depends on a holdoff time before starting the test to
ensure grace periods start later. This works fine with the default
holdoff time however it is not robust in situations where init takes
greater than the holdoff time to finish running. Or, as in my case:
I modified the rcuperf test locally to also run a thread that did
preempt disable/enable in a loop. This had the effect of slowing down
init. The end result was that the "batches:" counter in rcuperf was 0
causing a division by 0 error in the results. This counter was 0 because
only expedited GPs seem to happen, not normal ones which led to the
rcu_state.gp_seq counter remaining constant across grace periods which
unexpectedly happen to be expedited. The system was running expedited
RCU all the time because rcu_unexpedited_gp() would not have run yet
from init. In other words, the test would concurrently with init
booting in expedited GP mode.
To fix this properly, this commit waits until system_state is set to
SYSTEM_RUNNING before starting the test. This change is made just
before kernel_init() invokes rcu_end_inkernel_boot(), and this latter
is what turns off boot-time expediting of RCU grace periods.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The functions torture_onoff_cleanup() and torture_shuffle_cleanup()
are declared static and marked EXPORT_SYMBOL_GPL(), which is at best an
odd combination. Because these functions are not used outside of the
kernel/torture.c file they are defined in, this commit removes their
EXPORT_SYMBOL_GPL() marking.
Fixes: cc47ae0830 ("rcutorture: Abstract torture-test cleanup")
Signed-off-by: Denis Efremov <efremov@linux.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
During an actual call_rcu() flood, there would be frequent trips to
userspace (in-kernel call_rcu() floods must be otherwise housebroken).
Userspace execution allows a great many things to interrupt execution,
and rcutorture needs to also allow such interruptions. This commit
therefore causes call_rcu() floods to occasionally invoke schedule(),
thus preventing spurious rcutorture failures due to other parts of the
kernel becoming irate at the call_rcu() flood events.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcu_bh rcuperf type was removed by commit 620d246065cd("rcuperf:
Remove the "rcu_bh" and "sched" torture types"), but it lives on in the
MODULE_PARM_DESC() of perf_type. This commit therefore changes that
module-parameter description to substitute srcu for rcu_bh.
Signed-off-by: Xiao Yang <ice_yangxiao@163.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The debug_locks flag can never be true at the end of
rcu_read_lock_sched_held() because it is already checked by the earlier
call todebug_lockdep_rcu_enabled(). This commit therefore removes this
redundant check.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The rcu_dereference_raw_notrace() API name is confusing. It is equivalent
to rcu_dereference_raw() except that it also does sparse pointer checking.
There are only a few users of rcu_dereference_raw_notrace(). This patches
renames all of them to be rcu_dereference_raw_check() with the "_check()"
indicating sparse checking.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
[ paulmck: Fix checkpatch warnings about parentheses. ]
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The return value of rcu_spawn_one_boost_kthread() is not used any longer.
This commit therefore changes its return type from int to void, and
removes the cast to void from its callers.
Signed-off-by: Byungchul Park <byungchul.park@lge.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because pointer output is now obfuscated, and because what you really
want to know is whether or not the callback lists are empty, this commit
replaces the srcu_data structure's head callback pointer printout with
a single character that is "." is the callback list is empty or "C"
otherwise.
This is the only remaining user of rcu_segcblist_head(), so this
commit also removes this function's definition. It also turns out that
rcu_segcblist_tail() no longer has any callers, so this commit removes
that function's definition while in the area. They were both marked
"Interim", and their end has come.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
The synchronize_rcu_expedited() function has an INIT_WORK_ONSTACK(),
but lacks the corresponding destroy_work_on_stack(). This commit
therefore adds destroy_work_on_stack().
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Andrea Arcangeli <aarcange@redhat.com>
This commit adds a rcu_cpu_stall_ftrace_dump kernel boot parameter, that,
when set, causes the trace buffer to be dumped after an RCU CPU stall
warning is printed. This kernel boot parameter is disabled by default,
maintaining compatibility with previous behavior.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Commit bb73c52bad ("rcu: Don't disable preemption for Tiny and Tree
RCU readers") removed the barrier() calls from rcu_read_lock() and
rcu_write_lock() in CONFIG_PREEMPT=n&&CONFIG_PREEMPT_COUNT=n kernels.
Within RCU, this commit was OK, but it failed to account for things like
get_user() that can pagefault and that can be reordered by the compiler.
Lack of the barrier() calls in rcu_read_lock() and rcu_read_unlock()
can cause these page faults to migrate into RCU read-side critical
sections, which in CONFIG_PREEMPT=n kernels could result in too-short
grace periods and arbitrary misbehavior. Please see commit 386afc9114
("spinlocks and preemption points need to be at least compiler barriers")
and Linus's commit 66be4e66a7 ("rcu: locking and unlocking need to
always be at least barriers"), this last of which restores the barrier()
call to both rcu_read_lock() and rcu_read_unlock().
This commit removes barrier() calls that are no longer needed given that
the addition of them in Linus's commit noted above. The combination of
this commit and Linus's commit effectively reverts commit bb73c52bad
("rcu: Don't disable preemption for Tiny and Tree RCU readers").
Reported-by: Herbert Xu <herbert@gondor.apana.org.au>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
[ paulmck: Fix embarrassing typo located by Alan Stern. ]
The TASKS03 and TREE04 rcutorture scenarios produce the following
lockdep complaint:
------------------------------------------------------------------------
================================
WARNING: inconsistent lock state
5.2.0-rc1+ #513 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
migration/1/14 [HC0[0]:SC0[0]:HE1:SE1] takes:
(____ptrval____) (tick_broadcast_lock){?...}, at: tick_broadcast_offline+0xf/0x70
{IN-HARDIRQ-W} state was registered at:
lock_acquire+0xb0/0x1c0
_raw_spin_lock_irqsave+0x3c/0x50
tick_broadcast_switch_to_oneshot+0xd/0x40
tick_switch_to_oneshot+0x4f/0xd0
hrtimer_run_queues+0xf3/0x130
run_local_timers+0x1c/0x50
update_process_times+0x1c/0x50
tick_periodic+0x26/0xc0
tick_handle_periodic+0x1a/0x60
smp_apic_timer_interrupt+0x80/0x2a0
apic_timer_interrupt+0xf/0x20
_raw_spin_unlock_irqrestore+0x4e/0x60
rcu_nocb_gp_kthread+0x15d/0x590
kthread+0xf3/0x130
ret_from_fork+0x3a/0x50
irq event stamp: 171
hardirqs last enabled at (171): [<ffffffff8a201a37>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (170): [<ffffffff8a201a53>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last enabled at (0): [<ffffffff8a264ee0>] copy_process.part.56+0x650/0x1cb0
softirqs last disabled at (0): [<0000000000000000>] 0x0
other info that might help us debug this:
Possible unsafe locking scenario:
CPU0
----
lock(tick_broadcast_lock);
<Interrupt>
lock(tick_broadcast_lock);
*** DEADLOCK ***
1 lock held by migration/1/14:
#0: (____ptrval____) (clockevents_lock){+.+.}, at: tick_offline_cpu+0xf/0x30
stack backtrace:
CPU: 1 PID: 14 Comm: migration/1 Not tainted 5.2.0-rc1+ #513
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS Bochs 01/01/2011
Call Trace:
dump_stack+0x5e/0x8b
print_usage_bug+0x1fc/0x216
? print_shortest_lock_dependencies+0x1b0/0x1b0
mark_lock+0x1f2/0x280
__lock_acquire+0x1e0/0x18f0
? __lock_acquire+0x21b/0x18f0
? _raw_spin_unlock_irqrestore+0x4e/0x60
lock_acquire+0xb0/0x1c0
? tick_broadcast_offline+0xf/0x70
_raw_spin_lock+0x33/0x40
? tick_broadcast_offline+0xf/0x70
tick_broadcast_offline+0xf/0x70
tick_offline_cpu+0x16/0x30
take_cpu_down+0x7d/0xa0
multi_cpu_stop+0xa2/0xe0
? cpu_stop_queue_work+0xc0/0xc0
cpu_stopper_thread+0x6d/0x100
smpboot_thread_fn+0x169/0x240
kthread+0xf3/0x130
? sort_range+0x20/0x20
? kthread_cancel_delayed_work_sync+0x10/0x10
ret_from_fork+0x3a/0x50
------------------------------------------------------------------------
To reproduce, run the following rcutorture test:
tools/testing/selftests/rcutorture/bin/kvm.sh --duration 5 --kconfig "CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_PROVE_LOCKING=y" --configs "TASKS03 TREE04"
It turns out that tick_broadcast_offline() was an innocent bystander.
After all, interrupts are supposed to be disabled throughout
take_cpu_down(), and therefore should have been disabled upon entry to
tick_offline_cpu() and thus to tick_broadcast_offline(). This suggests
that one of the CPU-hotplug notifiers was incorrectly enabling interrupts,
and leaving them enabled on return.
Some debugging code showed that the culprit was sched_cpu_dying().
It had irqs enabled after return from sched_tick_stop(). Which in turn
had irqs enabled after return from cancel_delayed_work_sync(). Which is a
wrapper around __cancel_work_timer(). Which can sleep in the case where
something else is concurrently trying to cancel the same delayed work,
and as Thomas Gleixner pointed out on IRC, sleeping is a decidedly bad
idea when you are invoked from take_cpu_down(), regardless of the state
you leave interrupts in upon return.
Code inspection located no reason why the delayed work absolutely
needed to be canceled from sched_tick_stop(): The work is not
bound to the outgoing CPU by design, given that the whole point is
to collect statistics without disturbing the outgoing CPU.
This commit therefore simply drops the cancel_delayed_work_sync() from
sched_tick_stop(). Instead, a new ->state field is added to the tick_work
structure so that the delayed-work handler function sched_tick_remote()
can avoid reposting itself. A cpu_is_offline() check is also added to
sched_tick_remote() to avoid mucking with the state of an offlined CPU
(though it does appear safe to do so). The sched_tick_start() and
sched_tick_stop() functions also update ->state, and sched_tick_start()
also schedules the delayed work if ->state indicates that it is not
already in flight.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
[ paulmck: Apply Peter Zijlstra and Frederic Weisbecker atomics feedback. ]
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Security is a wonderful thing, but so is the ability to debug based on
lockdep warnings. This commit therefore makes lockdep lock addresses
visible in the clear.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Because __rcu_read_unlock() can be preempted just before the call to
rcu_read_unlock_special(), it is possible for a task to be preempted just
before it would have fully exited its RCU read-side critical section.
This would result in a needless extension of that critical section until
that task was resumed, which might in turn result in a needlessly
long grace period, needless RCU priority boosting, and needless
force-quiescent-state actions. Therefore, rcu_note_context_switch()
invokes __rcu_read_unlock() followed by rcu_preempt_deferred_qs() when
it detects this situation. This action by rcu_note_context_switch()
ends the RCU read-side critical section immediately.
Of course, once the task resumes, it will invoke rcu_read_unlock_special()
redundantly. This is harmless because the fact that a preemption
happened means that interrupts, preemption, and softirqs cannot
have been disabled, so there would be no deferred quiescent state.
While ->rcu_read_lock_nesting remains less than zero, none of the
->rcu_read_unlock_special.b bits can be set, and they were all zeroed by
the call to rcu_note_context_switch() at task-preemption time. Therefore,
setting ->rcu_read_unlock_special.b.exp_hint to false has no effect.
Therefore, the extra call to rcu_preempt_deferred_qs_irqrestore()
would return immediately. With one possible exception, which is
if an expedited grace period started just as the task was being
resumed, which could leave ->exp_deferred_qs set. This will cause
rcu_preempt_deferred_qs_irqrestore() to invoke rcu_report_exp_rdp(),
reporting the quiescent state, just as it should. (Such an expedited
grace period won't affect the preemption code path due to interrupts
having already been disabled.)
But when rcu_note_context_switch() invokes __rcu_read_unlock(), it
is doing so with preemption disabled, hence __rcu_read_unlock() will
unconditionally defer the quiescent state, only to immediately invoke
rcu_preempt_deferred_qs(), thus immediately reporting the deferred
quiescent state. It turns out to be safe (and faster) to instead
just invoke rcu_preempt_deferred_qs() without the __rcu_read_unlock()
middleman.
Because this is the invocation during the preemption (as opposed to
the invocation just after the resume), at least one of the bits in
->rcu_read_unlock_special.b must be set and ->rcu_read_lock_nesting
must be negative. This means that rcu_preempt_need_deferred_qs() must
return true, avoiding the early exit from rcu_preempt_deferred_qs().
Thus, rcu_preempt_deferred_qs_irqrestore() will be invoked immediately,
as required.
This commit therefore simplifies the CONFIG_PREEMPT=y version of
rcu_note_context_switch() by removing the "else if" branch of its
"if" statement. This change means that all callers that would have
invoked rcu_read_unlock_special() followed by rcu_preempt_deferred_qs()
will now simply invoke rcu_preempt_deferred_qs(), thus avoiding the
rcu_read_unlock_special() middleman when __rcu_read_unlock() is preempted.
Cc: rcu@vger.kernel.org
Cc: kernel-team@android.com
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Threaded interrupts provide additional interesting interactions between
RCU and raise_softirq() that can result in self-deadlocks in v5.0-2 of
the Linux kernel. These self-deadlocks can be provoked in susceptible
kernels within a few minutes using the following rcutorture command on
an 8-CPU system:
tools/testing/selftests/rcutorture/bin/kvm.sh --duration 5 --configs "TREE03" --bootargs "threadirqs"
Although post-v5.2 RCU commits have at least greatly reduced the
probability of these self-deadlocks, this was entirely by accident.
Although this sort of accident should be rowdily celebrated on those
rare occasions when it does occur, such celebrations should be quickly
followed by a principled patch, which is what this patch purports to be.
The key point behind this patch is that when in_interrupt() returns
true, __raise_softirq_irqoff() will never attempt a wakeup. Therefore,
if in_interrupt(), calls to raise_softirq*() are both safe and
extremely cheap.
This commit therefore replaces the in_irq() calls in the "if" statement
in rcu_read_unlock_special() with in_interrupt() and simplifies the
"if" condition to the following:
if (irqs_were_disabled && use_softirq &&
(in_interrupt() ||
(exp && !t->rcu_read_unlock_special.b.deferred_qs))) {
raise_softirq_irqoff(RCU_SOFTIRQ);
} else {
/* Appeal to the scheduler. */
}
The rationale behind the "if" condition is as follows:
1. irqs_were_disabled: If interrupts are enabled, we should
instead appeal to the scheduler so as to let the upcoming
irq_enable()/local_bh_enable() do the rescheduling for us.
2. use_softirq: If this kernel isn't using softirq, then
raise_softirq_irqoff() will be unhelpful.
3. a. in_interrupt(): If this returns true, the subsequent
call to raise_softirq_irqoff() is guaranteed not to
do a wakeup, so that call will be both very cheap and
quite safe.
b. Otherwise, if !in_interrupt() the raise_softirq_irqoff()
might do a wakeup, which is expensive and, in some
contexts, unsafe.
i. The "exp" (an expedited RCU grace period is being
blocked) says that the wakeup is worthwhile, and:
ii. The !.deferred_qs says that scheduler locks
cannot be held, so the wakeup will be safe.
Backporting this requires considerable care, so no auto-backport, please!
Fixes: 05f415715c ("rcu: Speed up expedited GPs when interrupting RCU reader")
Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
In !use_softirq runs, we clearly cannot rely on raise_softirq() and
its lightweight bit setting, so we must instead do some form of wakeup.
In the absence of a self-IPI when interrupts are disabled, these wakeups
can be delayed until the next interrupt occurs. This means that calling
invoke_rcu_core() doesn't actually do any expediting.
In this case, it is better to take the "else" clause, which sets the
current CPU's resched bits and, if there is an expedited grace period
in flight, uses IRQ-work to force the needed self-IPI. This commit
therefore removes the "else if" clause that calls invoke_rcu_core().
Reported-by: Scott Wood <swood@redhat.com>
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
Since we always allocate memory, allocate just a little bit more
for the BPF program in case it need to override user input with
bigger value. The canonical example is TCP_CONGESTION where
input string might be too small to override (nv -> bbr or cubic).
16 bytes are chosen to match the size of TCP_CA_NAME_MAX and can
be extended in the future if needed.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
This adds the P_PIDFD type to waitid().
One of the last remaining bits for the pidfd api is to make it possible
to wait on pidfds. With P_PIDFD added to waitid() the parts of userspace
that want to use the pidfd api to exclusively manage processes can do so
now.
One of the things this will unblock in the future is the ability to make
it possible to retrieve the exit status via waitid(P_PIDFD) for
non-parent processes if handed a _suitable_ pidfd that has this feature
set. This is similar to what you can do on FreeBSD with kqueue(). It
might even end up being possible to wait on a process as a non-parent if
an appropriate property is enabled on the pidfd.
With P_PIDFD no scoping of the process identified by the pidfd is
possible, i.e. it explicitly blocks things such as wait4(-1), wait4(0),
waitid(P_ALL), waitid(P_PGID) etc. It only allows for semantics
equivalent to wait4(pid), waitid(P_PID). Users that need scoping should
rely on pid-based wait*() syscalls for now.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: David Howells <dhowells@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Link: https://lore.kernel.org/r/20190727222229.6516-2-christian@brauner.io
Timer deletion on PREEMPT_RT is prone to priority inversion and live
locks. The hrtimer code has a synchronization mechanism for this. Posix CPU
timers will grow one.
But that mechanism cannot be invoked while holding the k_itimer lock
because that can deadlock against the running timer callback. So the lock
must be dropped which allows the timer to be freed.
The timer free can be prevented by taking RCU readlock before dropping the
lock, but because the rcu_head is part of the 'it' union a concurrent free
will overwrite the hrtimer on which the task is trying to synchronize.
Move the rcu_head out of the union to prevent this.
[ tglx: Fixed up kernel-doc. Rewrote changelog ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.965541887@linutronix.de
As a preparatory step for adding the PREEMPT RT specific synchronization
mechanism to wait for a running timer callback, rework the timer cancel
retry loops so they call a common function. This allows trivial
substitution in one place.
Originally-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.874901027@linutronix.de
do_timer_settime() has a 'flags' argument and uses 'flag' for the interrupt
flags, which is confusing at best.
Rename the argument so 'flags' can be used for interrupt flags as usual.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.782664411@linutronix.de
Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.
As a benefit the retry loop gains the missing cpu_relax() on !RT.
[ tglx: Split out of combo patch ]
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.690771827@linutronix.de
Use the hrtimer_cancel_wait_running() synchronization mechanism to prevent
priority inversion and live locks on PREEMPT_RT.
[ tglx: Split out of combo patch ]
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190730223828.508744705@linutronix.de
SCHED_DEADLINE inactive timer needs to run in hardirq context (as
dl_task_timer already does) on PREEMPT_RT
Change the mode to HRTIMER_MODE_REL_HARD.
[ tglx: Fixed up the start site, so mode debugging works ]
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190731103715.4047-1-juri.lelli@redhat.com
When PREEMPT_RT is enabled, the soft interrupt thread can be preempted. If
the soft interrupt thread is preempted in the middle of a timer callback,
then calling del_timer_sync() can lead to two issues:
- If the caller is on a remote CPU then it has to spin wait for the timer
handler to complete. This can result in unbound priority inversion.
- If the caller originates from the task which preempted the timer
handler on the same CPU, then spin waiting for the timer handler to
complete is never going to end.
To avoid these issues, add a new lock to the timer base which is held
around the execution of the timer callbacks. If del_timer_sync() detects
that the timer callback is currently running, it blocks on the expiry
lock. When the callback is finished, the expiry lock is dropped by the
softirq thread which wakes up the waiter and the system makes progress.
This addresses both the priority inversion and the life lock issues.
This mechanism is not used for timers which are marked IRQSAFE as for those
preemption is disabled accross the callback and therefore this situation
cannot happen. The callbacks for such timers need to be individually
audited for RT compliance.
The same issue can happen in virtual machines when the vCPU which runs a
timer callback is scheduled out. If a second vCPU of the same guest calls
del_timer_sync() it will spin wait for the other vCPU to be scheduled back
in. The expiry lock mechanism would avoid that. It'd be trivial to enable
this when paravirt spinlocks are enabled in a guest, but it's not clear
whether this is an actual problem in the wild, so for now it's an RT only
mechanism.
As the softirq thread can be preempted with PREEMPT_RT=y, the SMP variant
of del_timer_sync() needs to be used on UP as well.
[ tglx: Refactored it for mainline ]
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.832418500@linutronix.de
When PREEMPT_RT is enabled, the soft interrupt thread can be preempted. If
the soft interrupt thread is preempted in the middle of a timer callback,
then calling hrtimer_cancel() can lead to two issues:
- If the caller is on a remote CPU then it has to spin wait for the timer
handler to complete. This can result in unbound priority inversion.
- If the caller originates from the task which preempted the timer
handler on the same CPU, then spin waiting for the timer handler to
complete is never going to end.
To avoid these issues, add a new lock to the timer base which is held
around the execution of the timer callbacks. If hrtimer_cancel() detects
that the timer callback is currently running, it blocks on the expiry
lock. When the callback is finished, the expiry lock is dropped by the
softirq thread which wakes up the waiter and the system makes progress.
This addresses both the priority inversion and the life lock issues.
The same issue can happen in virtual machines when the vCPU which runs a
timer callback is scheduled out. If a second vCPU of the same guest calls
hrtimer_cancel() it will spin wait for the other vCPU to be scheduled back
in. The expiry lock mechanism would avoid that. It'd be trivial to enable
this when paravirt spinlocks are enabled in a guest, but it's not clear
whether this is an actual problem in the wild, so for now it's an RT only
mechanism.
[ tglx: Refactored it for mainline ]
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.737767218@linutronix.de
On PREEMPT_RT enabled kernels hrtimers which are not explicitely marked for
hard interrupt expiry mode are moved into soft interrupt context either for
latency reasons or because the hrtimer callback takes regular spinlocks or
invokes other functions which are not suitable for hard interrupt context
on PREEMPT_RT.
The hrtimer_sleeper callback is RT compatible in hard interrupt context,
but there is a latency concern: Untrusted userspace can spawn many threads
which arm timers for the same expiry time on the same CPU. On expiry that
causes a latency spike due to the wakeup of a gazillion threads.
OTOH, priviledged real-time user space applications rely on the low latency
of hard interrupt wakeups. These syscall related wakeups are all based on
hrtimer sleepers.
If the current task is in a real-time scheduling class, mark the mode for
hard interrupt expiry.
[ tglx: Split out of a larger combo patch. Added changelog ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.645792403@linutronix.de
On PREEMPT_RT not all hrtimers can be expired in hard interrupt context
even if that is perfectly fine on a PREEMPT_RT=n kernel, e.g. because they
take regular spinlocks. Also for latency reasons PREEMPT_RT tries to defer
most hrtimers' expiry into softirq context.
hrtimers marked with HRTIMER_MODE_HARD must be kept in hard interrupt
context expiry mode. Add the required logic.
No functional change for PREEMPT_RT=n kernels.
[ tglx: Split out of a larger combo patch. Added changelog ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.551967692@linutronix.de
The tick related hrtimers, which drive the scheduler tick and hrtimer based
broadcasting are required to expire in hard interrupt context for obvious
reasons.
Mark them so PREEMPT_RT kernels wont move them to soft interrupt expiry.
Make the horribly formatted RCU_NONIDLE bracket maze readable while at it.
No functional change,
[ tglx: Split out from larger combo patch. Add changelog ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.459144407@linutronix.de
The watchdog hrtimer must expire in hard interrupt context even on
PREEMPT_RT=y kernels as otherwise the hard/softlockup detection logic would
not work.
No functional change.
[ tglx: Split out from larger combo patch. Added changelog ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.262895510@linutronix.de
To guarantee that the multiplexing mechanism and the hrtimer driven events
work on PREEMPT_RT enabled kernels it's required that the related hrtimers
expire in hard interrupt context. Mark them so PREEMPT_RT kernels wont
defer them to soft interrupt context.
No functional change.
[ tglx: Split out of larger combo patch. Added changelog ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.169509224@linutronix.de
The scheduler related hrtimers need to expire in hard interrupt context
even on PREEMPT_RT enabled kernels. Mark then as such.
No functional change.
[ tglx: Split out from larger combo patch. Add changelog. ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185753.077004842@linutronix.de
hrtimer_start_range_ns() has a WARN_ONCE() which verifies that a timer
which is marker for softirq expiry is not queued in the hard interrupt base
and vice versa.
When PREEMPT_RT is enabled, timers which are not explicitely marked to
expire in hard interrupt context are deferrred to the soft interrupt. So
the regular check would trigger.
Change the check, so when PREEMPT_RT is enabled, it is verified that the
timers marked for hard interrupt expiry are not tried to be queued for soft
interrupt expiry or any of the unmarked and softirq marked is tried to be
expired in hard interrupt context.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hrtimer_sleepers will gain a scheduling class dependent treatment on
PREEMPT_RT. Use the new hrtimer_sleeper_start_expires() function to make
that possible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hrtimer_sleepers will gain a scheduling class dependent treatment on
PREEMPT_RT. Create a wrapper around hrtimer_start_expires() to make that
possible.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
hrtimer_init_sleeper() calls require prior initialisation of the hrtimer
object which is embedded into the hrtimer_sleeper.
Combine the initialization and spare a function call. Fixup all call sites.
This is also a preparatory change for PREEMPT_RT to do hrtimer sleeper
specific initializations of the embedded hrtimer without modifying any of
the call sites.
No functional change.
[ anna-maria: Minor cleanups ]
[ tglx: Adopted to the removal of the task argument of
hrtimer_init_sleeper() and trivial polishing.
Folded a fix from Stephen Rothwell for the vsoc code ]
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185752.887468908@linutronix.de
- Fix trace event header include guards, as several did not match
the #define to the #ifdef
- Remove a redundant test to ftrace_graph_notrace_addr() that
was accidentally added.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXUFythQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qsjjAP41jDPQogZMaQZrPW1qyp69DHhuZXI2
j/d7A2LG76mCggD/WHPBk8P98IHk7pO5Ndl4yLKS3plMCYqTcgylpJLMXQI=
=yEpO
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"Two minor fixes:
- Fix trace event header include guards, as several did not match the
#define to the #ifdef
- Remove a redundant test to ftrace_graph_notrace_addr() that was
accidentally added"
* tag 'trace-v5.3-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
fgraph: Remove redundant ftrace_graph_notrace_addr() test
tracing: Fix header include guards in trace event headers
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.
Switch kprobes conditional over to CONFIG_PREEMPTION.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.516286187@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.
Switch the conditionals in the tracer over to CONFIG_PREEMPTION.
This is the first step to make the tracer work on RT. The other small
tweaks are submitted separately.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.409766323@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.
Switch the conditionals in RCU to use CONFIG_PREEMPTION.
That's the first step towards RCU on RT. The further tweaks are work in
progress. This neither touches the selftest bits which need a closer look
by Paul.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.210156346@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
CONFIG_PREEMPTION is selected by CONFIG_PREEMPT and by
CONFIG_PREEMPT_RT. Both PREEMPT and PREEMPT_RT require the same
functionality which today depends on CONFIG_PREEMPT.
Switch the preemption code, scheduler and init task over to use
CONFIG_PREEMPTION.
That's the first step towards RT in that area. The more complex changes are
coming separately.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: http://lkml.kernel.org/r/20190726212124.117528401@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We already have tested it before. The second one should be removed.
With this change, the performance should have little improvement.
Link: http://lkml.kernel.org/r/20190730140850.7927-1-changbin.du@gmail.com
Cc: stable@vger.kernel.org
Fixes: 9cd2992f2d ("fgraph: Have set_graph_notrace only affect function_graph tracer")
Signed-off-by: Changbin Du <changbin.du@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
All callers hand in 'current' and that's the only task pointer which
actually makes sense. Remove the task argument and set current in the
function.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190726185752.791885290@linutronix.de
Since commit b191d6491b ("pidfd: fix a poll race when setting exit_state")
we unconditionally set exit_state to EXIT_ZOMBIE before calling into
do_notify_parent(). This was done to eliminate a race when querying
exit_state in do_notify_pidfd().
Back then we decided to do the absolute minimal thing to fix this and
not touch the rest of the exit_notify() function where exit_state is
set.
Since this fix has not caused any issues change the setting of
exit_state to EXIT_DEAD in the autoreap case to account for the fact hat
exit_state is set to EXIT_ZOMBIE unconditionally. This fix was planned
but also explicitly requested in [1] and makes the whole code more
consistent.
/* References */
[1]: https://lore.kernel.org/lkml/CAHk-=wigcxGFR2szue4wavJtH5cYTTeNES=toUBVGsmX0rzX+g@mail.gmail.com
Signed-off-by: Christian Brauner <christian@brauner.io>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
The FSF does not reside in "675 Mass Ave, Cambridge" anymore...
let's replace the old GPL boilerplate code with a proper SPDX
identifier instead.
Signed-off-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Some arches (e.g., arm64, x86) have moved towards non-executable
module_alloc() allocations for security hardening reasons. That means
that the module loader will need to set the text section of a module to
executable, regardless of whether or not CONFIG_STRICT_MODULE_RWX is set.
When CONFIG_STRICT_MODULE_RWX=y, module section allocations are always
page-aligned to handle memory rwx permissions. On some arches with
CONFIG_STRICT_MODULE_RWX=n however, when setting the module text to
executable, the BUG_ON() in frob_text() gets triggered since module
section allocations are not page-aligned when CONFIG_STRICT_MODULE_RWX=n.
Since the set_memory_* API works with pages, and since we need to call
set_memory_x() regardless of whether CONFIG_STRICT_MODULE_RWX is set, we
might as well page-align all module section allocations for ease of
managing rwx permissions of module sections (text, rodata, etc).
Fixes: 2eef1399a8 ("modules: fix BUG when load module with rodata=n")
Reported-by: Martin Kaiser <lists@kaiser.cx>
Reported-by: Bartosz Golaszewski <brgl@bgdev.pl>
Tested-by: David Lechner <david@lechnology.com>
Tested-by: Martin Kaiser <martin@kaiser.cx>
Tested-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
A common pattern when using xdp_redirect_map() is to create a device map
where the lookup key is simply ifindex. Because device maps are arrays,
this leaves holes in the map, and the map has to be sized to fit the
largest ifindex, regardless of how many devices actually are actually
needed in the map.
This patch adds a second type of device map where the key is looked up
using a hashmap, instead of being used as an array index. This allows maps
to be densely packed, so they can be smaller.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
The subsequent patch to add a new devmap sub-type can re-use much of the
initialisation and allocation code, so refactor it into separate functions.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Previously a condition got missed where the pidfd waiters are awakened
before the exit_state gets set. This can result in a missed notification
[1] and the polling thread waiting forever.
It is fixed now, however it would be nice to avoid this kind of issue
going unnoticed in the future. So just add a warning to catch it in the
future.
/* References */
[1]: https://lore.kernel.org/lkml/20190717172100.261204-1-joel@joelfernandes.org/
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lore.kernel.org/r/20190724164816.201099-1-joel@joelfernandes.org
Signed-off-by: Christian Brauner <christian@brauner.io>
According to the original dma_direct_alloc_pages() code:
{
unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
if (!dma_release_from_contiguous(dev, page, count))
__free_pages(page, get_order(size));
}
The count parameter for dma_release_from_contiguous() was page
aligned before the right-shifting operation, while the new API
dma_free_contiguous() forgets to have PAGE_ALIGN() at the size.
So this patch simply adds it to prevent any corner case.
Fixes: fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The dma_alloc_contiguous() limits align at CONFIG_CMA_ALIGNMENT for
cma_alloc() however it does not restore it for the fallback routine.
This will result in a size mismatch between the allocation and free
when running into the fallback routines after cma_alloc() fails, if
the align is larger than CONFIG_CMA_ALIGNMENT.
This patch adds a cma_align to take care of cma_alloc() and prevent
the align from being overwritten.
Fixes: fdaeec198ada ("dma-contiguous: add dma_{alloc,free}_contiguous() helpers")
Reported-by: Dafna Hirschfeld <dafna.hirschfeld@collabora.com>
Signed-off-by: Nicolin Chen <nicoleotsuka@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Pull scheduler fixes from Thomas Gleixner:
"Two fixes for the fair scheduling class:
- Prevent freeing memory which is accessible by concurrent readers
- Make the RCU annotations for numa groups consistent"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Use RCU accessors consistently for ->numa_group
sched/fair: Don't free p->numa_faults with concurrent readers
Pull perf fixes from Thomas Gleixner:
"A pile of perf related fixes:
Kernel:
- Fix SLOTS PEBS event constraints for Icelake CPUs
- Add the missing mask bit to allow counting hardware generated
prefetches on L3 for Icelake CPUs
- Make the test for hypervisor platforms more accurate (as far as
possible)
- Handle PMUs correctly which override event->cpu
- Yet another missing fallthrough annotation
Tools:
perf.data:
- Fix loading of compressed data split across adjacent records
- Fix buffer size setting for processing CPU topology perf.data
header.
perf stat:
- Fix segfault for event group in repeat mode
- Always separate "stalled cycles per insn" line, it was being
appended to the "instructions" line.
perf script:
- Fix --max-blocks man page description.
- Improve man page description of metrics.
- Fix off by one in brstackinsn IPC computation.
perf probe:
- Avoid calling freeing routine multiple times for same pointer.
perf build:
- Do not use -Wshadow on gcc < 4.8, avoiding too strict warnings
treated as errors, breaking the build"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Mark expected switch fall-throughs
perf/core: Fix creating kernel counters for PMUs that override event->cpu
perf/x86: Apply more accurate check on hypervisor platform
perf/x86/intel: Fix invalid Bit 13 for Icelake MSR_OFFCORE_RSP_x register
perf/x86/intel: Fix SLOTS PEBS event constraint
perf build: Do not use -Wshadow on gcc < 4.8
perf probe: Avoid calling freeing routine multiple times for same pointer
perf probe: Set pev->nargs to zero after freeing pev->args entries
perf session: Fix loading of compressed data split across adjacent records
perf stat: Always separate stalled cycles per insn
perf stat: Fix segfault for event group in repeat mode
perf tools: Fix proper buffer size for feature processing
perf script: Fix off by one in brstackinsn IPC computation
perf script: Improve man page description of metrics
perf script: Fix --max-blocks man page description
Pull locking fixes from Thomas Gleixner:
"A set of locking fixes:
- Address the fallout of the rwsem rework. Missing ACQUIREs and a
sanity check to prevent a use-after-free
- Add missing checks for unitialized mutexes when mutex debugging is
enabled.
- Remove the bogus code in the generic SMP variant of
arch_futex_atomic_op_inuser()
- Fixup the #ifdeffery in lockdep to prevent compile warnings"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/mutex: Test for initialized mutex
locking/lockdep: Clean up #ifdef checks
locking/lockdep: Hide unused 'class' variable
locking/rwsem: Add ACQUIRE comments
tty/ldsem, locking/rwsem: Add missing ACQUIRE to read_failed sleep loop
lcoking/rwsem: Add missing ACQUIRE to read_slowpath sleep loop
locking/rwsem: Add missing ACQUIRE to read_slowpath exit when queue is empty
locking/rwsem: Don't call owner_on_cpu() on read-owner
futex: Cleanup generic SMP variant of arch_futex_atomic_op_inuser()
With the removal of the padata timer, padata_do_serial no longer
needs special CPU handling, so remove it.
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
The function padata_reorder will use a timer when it cannot progress
while completed jobs are outstanding (pd->reorder_objects > 0). This
is suboptimal as if we do end up using the timer then it would have
introduced a gratuitous delay of one second.
In fact we can easily distinguish between whether completed jobs
are outstanding and whether we can make progress. All we have to
do is look at the next pqueue list.
This patch does that by replacing pd->processed with pd->cpu so
that the next pqueue is more accessible.
A work queue is used instead of the original try_again to avoid
hogging the CPU.
Note that we don't bother removing the work queue in
padata_flush_queues because the whole premise is broken. You
cannot flush async crypto requests so it makes no sense to even
try. A subsequent patch will fix it by replacing it with a ref
counting scheme.
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Alexei Starovoitov says:
====================
pull-request: bpf 2019-07-25
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) fix segfault in libbpf, from Andrii.
2) fix gso_segs access, from Eric.
3) tls/sockmap fixes, from Jakub and John.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The access() (and faccessat()) credentials change can cause an
unnecessary load on the RCU machinery because every access() call ends
up freeing the temporary access credential using RCU.
This isn't really noticeable on small machines, but if you have hundreds
of cores you can cause huge slowdowns due to RCU storms.
It's easy to avoid: the temporary access crededntials aren't actually
normally accessed using RCU at all, so we can avoid the whole issue by
just marking them as such.
* access-creds:
access: avoid the RCU grace period for the temporary subjective credentials
Compiling a kernel with both FAIR_GROUP_SCHED=n and RT_GROUP_SCHED=n
will generate a compiler warning:
kernel/sched/core.c: In function 'sched_init':
kernel/sched/core.c:5906:32: warning: variable 'ptr' set but not used
It is unnecessary to have both "alloc_size" and "ptr", so just combine
them.
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: valentin.schneider@arm.com
Link: https://lkml.kernel.org/r/20190720012319.884-1-cai@lca.pw
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On !CONFIG_RT_GROUP_SCHED configurations it is currently not possible to
move RT tasks between cgroups to which CPU controller has been attached;
but it is oddly possible to first move tasks around and then make them
RT (setschedule to FIFO/RR).
E.g.:
# mkdir /sys/fs/cgroup/cpu,cpuacct/group1
# chrt -fp 10 $$
# echo $$ > /sys/fs/cgroup/cpu,cpuacct/group1/tasks
bash: echo: write error: Invalid argument
# chrt -op 0 $$
# echo $$ > /sys/fs/cgroup/cpu,cpuacct/group1/tasks
# chrt -fp 10 $$
# cat /sys/fs/cgroup/cpu,cpuacct/group1/tasks
2345
2598
# chrt -p 2345
pid 2345's current scheduling policy: SCHED_FIFO
pid 2345's current scheduling priority: 10
Also, as Michal noted, it is currently not possible to enable CPU
controller on unified hierarchy with !CONFIG_RT_GROUP_SCHED (if there
are any kernel RT threads in root cgroup, they can't be migrated to the
newly created CPU controller's root in cgroup_update_dfl_csses()).
Existing code comes with a comment saying the "we don't support RT-tasks
being in separate groups". Such comment is however stale and belongs to
pre-RT_GROUP_SCHED times. Also, it doesn't make much sense for
!RT_GROUP_ SCHED configurations, since checks related to RT bandwidth
are not performed at all in these cases.
Make moving RT tasks between CPU controller groups viable by removing
special case check for RT (and DEADLINE) tasks.
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: rostedt@goodmis.org
Link: https://lkml.kernel.org/r/20190719063455.27328-1-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
No synchronisation mechanism exists between the cpuset subsystem and
calls to function __sched_setscheduler(). As such, it is possible that
new root domains are created on the cpuset side while a deadline
acceptance test is carried out in __sched_setscheduler(), leading to a
potential oversell of CPU bandwidth.
Grab cpuset_rwsem read lock from core scheduler, so to prevent
situations such as the one described above from happening.
The only exception is normalize_rt_tasks() which needs to work under
tasklist_lock and can't therefore grab cpuset_rwsem. We are fine with
this, as this function is only called by sysrq and, if that gets
triggered, DEADLINE guarantees are already gone out of the window
anyway.
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: mathieu.poirier@linaro.org
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-9-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
cpuset_rwsem is going to be acquired from sched_setscheduler() with a
following patch. There are however paths (e.g., spawn_ksoftirqd) in
which sched_scheduler() is eventually called while holding hotplug lock;
this creates a dependecy between hotplug lock (to be always acquired
first) and cpuset_rwsem (to be always acquired after hotplug lock).
Fix paths which currently take the two locks in the wrong order (after
a following patch is applied).
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: mathieu.poirier@linaro.org
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-7-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Holding cpuset_mutex means that cpusets are stable (only the holder can
make changes) and this is required for fixing a synchronization issue
between cpusets and scheduler core. However, grabbing cpuset_mutex from
setscheduler() hotpath (as implemented in a later patch) is a no-go, as
it would create a bottleneck for tasks concurrently calling
setscheduler().
Convert cpuset_mutex to be a percpu_rwsem (cpuset_rwsem), so that
setscheduler() will then be able to read lock it and avoid concurrency
issues.
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: mathieu.poirier@linaro.org
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-6-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When the topology of root domains is modified by CPUset or CPUhotplug
operations information about the current deadline bandwidth held in the
root domain is lost.
This patch addresses the issue by recalculating the lost deadline
bandwidth information by circling through the deadline tasks held in
CPUsets and adding their current load to the root domain they are
associated with.
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Juri Lelli <juri.lelli@redhat.com>
[ Various additional modifications. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: rostedt@goodmis.org
Cc: tj@kernel.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-4-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Calls to task_rq_unlock() are done several times in the
__sched_setscheduler() function. This is fine when only the rq lock needs to be
handled but not so much when other locks come into play.
This patch streamlines the release of the rq lock so that only one
location need to be modified when dealing with more than one lock.
No change of functionality is introduced by this patch.
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-3-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Introduce the partition_sched_domains_locked() function by taking
the mutex locking code out of the original function. That way
the work done by partition_sched_domains_locked() can be reused
without dropping the mutex lock.
No change of functionality is introduced by this patch.
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: bristot@redhat.com
Cc: claudio@evidence.eu.com
Cc: lizefan@huawei.com
Cc: longman@redhat.com
Cc: luca.abeni@santannapisa.it
Cc: rostedt@goodmis.org
Cc: tommaso.cucinotta@santannapisa.it
Link: https://lkml.kernel.org/r/20190719140000.31694-2-juri.lelli@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The same formula to check utilization against capacity (after
considering capacity_margin) is already used at 5 different locations.
This patch creates a new macro, fits_capacity(), which can be used from
all these locations without exposing the details of it and hence
simplify code.
All the 5 code locations are updated as well to use it..
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/b477ac75a2b163048bdaeb37f57b4c3f04f75a31.1559631700.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In real product setup, there will be houseeking CPUs in each nodes, it
is prefer to do housekeeping from local node, fallback to global online
cpumask if failed to find houseeking CPU from local node.
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1561711901-4755-2-git-send-email-wanpengli@tencent.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
sched_info_on() is called with unlikely hint, however, the test
is to be a constant(1) on which compiler will do nothing when
make defconfig, so remove the hint.
Also, fix a lack of {}.
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: up2wing@gmail.com
Cc: wang.liang82@zte.com.cn
Cc: xue.zhihong@zte.com.cn
Link: https://lkml.kernel.org/r/1562301307-43002-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Returning the pointer that was passed in allows us to write
slightly more idiomatic code. Convert a few users.
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190704221323.24290-1-willy@infradead.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We try to find an idle CPU to run the next task, but in case we don't
find an idle CPU it is better to pick a CPU which will run the task the
soonest, for performance reason.
A CPU which isn't idle but has only SCHED_IDLE activity queued on it
should be a good target based on this criteria as any normal fair task
will most likely preempt the currently running SCHED_IDLE task
immediately. In fact, choosing a SCHED_IDLE CPU over a fully idle one
shall give better results as it should be able to run the task sooner
than an idle CPU (which requires to be woken up from an idle state).
This patch updates both fast and slow paths with this optimization.
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Daniel Lezcano <daniel.lezcano@linaro.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: chris.redpath@arm.com
Cc: quentin.perret@linaro.org
Cc: songliubraving@fb.com
Cc: steven.sistare@oracle.com
Cc: subhra.mazumdar@oracle.com
Cc: tkjos@google.com
Link: https://lkml.kernel.org/r/eeafa25fdeb6f6edd5b2da716bc8f0ba7708cbcf.1561523542.git.viresh.kumar@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
time/tick-broadcast: Fix tick_broadcast_offline() lockdep complaint
The TASKS03 and TREE04 rcutorture scenarios produce the following
lockdep complaint:
WARNING: inconsistent lock state
5.2.0-rc1+ #513 Not tainted
--------------------------------
inconsistent {IN-HARDIRQ-W} -> {HARDIRQ-ON-W} usage.
migration/1/14 [HC0[0]:SC0[0]:HE1:SE1] takes:
(____ptrval____) (tick_broadcast_lock){?...}, at: tick_broadcast_offline+0xf/0x70
{IN-HARDIRQ-W} state was registered at:
lock_acquire+0xb0/0x1c0
_raw_spin_lock_irqsave+0x3c/0x50
tick_broadcast_switch_to_oneshot+0xd/0x40
tick_switch_to_oneshot+0x4f/0xd0
hrtimer_run_queues+0xf3/0x130
run_local_timers+0x1c/0x50
update_process_times+0x1c/0x50
tick_periodic+0x26/0xc0
tick_handle_periodic+0x1a/0x60
smp_apic_timer_interrupt+0x80/0x2a0
apic_timer_interrupt+0xf/0x20
_raw_spin_unlock_irqrestore+0x4e/0x60
rcu_nocb_gp_kthread+0x15d/0x590
kthread+0xf3/0x130
ret_from_fork+0x3a/0x50
irq event stamp: 171
hardirqs last enabled at (171): [<ffffffff8a201a37>] trace_hardirqs_on_thunk+0x1a/0x1c
hardirqs last disabled at (170): [<ffffffff8a201a53>] trace_hardirqs_off_thunk+0x1a/0x1c
softirqs last enabled at (0): [<ffffffff8a264ee0>] copy_process.part.56+0x650/0x1cb0
softirqs last disabled at (0): [<0000000000000000>] 0x0
[...]
To reproduce, run the following rcutorture test:
$ tools/testing/selftests/rcutorture/bin/kvm.sh --duration 5 --kconfig "CONFIG_DEBUG_LOCK_ALLOC=y CONFIG_PROVE_LOCKING=y" --configs "TASKS03 TREE04"
It turns out that tick_broadcast_offline() was an innocent bystander.
After all, interrupts are supposed to be disabled throughout
take_cpu_down(), and therefore should have been disabled upon entry to
tick_offline_cpu() and thus to tick_broadcast_offline(). This suggests
that one of the CPU-hotplug notifiers was incorrectly enabling interrupts,
and leaving them enabled on return.
Some debugging code showed that the culprit was sched_cpu_dying().
It had irqs enabled after return from sched_tick_stop(). Which in turn
had irqs enabled after return from cancel_delayed_work_sync(). Which is a
wrapper around __cancel_work_timer(). Which can sleep in the case where
something else is concurrently trying to cancel the same delayed work,
and as Thomas Gleixner pointed out on IRC, sleeping is a decidedly bad
idea when you are invoked from take_cpu_down(), regardless of the state
you leave interrupts in upon return.
Code inspection located no reason why the delayed work absolutely
needed to be canceled from sched_tick_stop(): The work is not
bound to the outgoing CPU by design, given that the whole point is
to collect statistics without disturbing the outgoing CPU.
This commit therefore simply drops the cancel_delayed_work_sync() from
sched_tick_stop(). Instead, a new ->state field is added to the tick_work
structure so that the delayed-work handler function sched_tick_remote()
can avoid reposting itself. A cpu_is_offline() check is also added to
sched_tick_remote() to avoid mucking with the state of an offlined CPU
(though it does appear safe to do so). The sched_tick_start() and
sched_tick_stop() functions also update ->state, and sched_tick_start()
also schedules the delayed work if ->state indicates that it is not
already in flight.
Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>
[ paulmck: Apply Peter Zijlstra and Frederic Weisbecker atomics feedback. ]
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190625165238.GJ26519@linux.ibm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The load_balance() has a dedicated mecanism to detect when an imbalance
is due to CPU affinity and must be handled at parent level. In this case,
the imbalance field of the parent's sched_group is set.
The description of sg_imbalanced() gives a typical example of two groups
of 4 CPUs each and 4 tasks each with a cpumask covering 1 CPU of the first
group and 3 CPUs of the second group. Something like:
{ 0 1 2 3 } { 4 5 6 7 }
* * * *
But the load_balance fails to fix this UC on my octo cores system
made of 2 clusters of quad cores.
Whereas the load_balance is able to detect that the imbalanced is due to
CPU affinity, it fails to fix it because the imbalance field is cleared
before letting parent level a chance to run. In fact, when the imbalance is
detected, the load_balance reruns without the CPU with pinned tasks. But
there is no other running tasks in the situation described above and
everything looks balanced this time so the imbalance field is immediately
cleared.
The imbalance field should not be cleared if there is no other task to move
when the imbalance is detected.
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1561996022-28829-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
We only need to set the callback_head worker function once, do it
during sched_fork().
While at it, move the comment regarding double task_work addition to
init_numa_balancing(), since the double add sentinel is first set there.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: mgorman@suse.de
Cc: riel@surriel.com
Link: https://lkml.kernel.org/r/20190715102508.32434-3-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
To reference task_numa_work() from within init_numa_balancing(), we
need the former to be declared before the latter. Do just that.
This is a pure code movement.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: mgorman@suse.de
Cc: riel@surriel.com
Link: https://lkml.kernel.org/r/20190715102508.32434-2-valentin.schneider@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Re-evaluating the bitmap wheight of the online cpus bitmap in every
invocation of num_online_cpus() over and over is a pretty useless
exercise. Especially when num_online_cpus() is used in code paths
like the IPI delivery of x86 or the membarrier code.
Cache the number of online CPUs in the core and just return the cached
variable. The accessor function provides only a snapshot when used without
protection against concurrent CPU hotplug.
The storage needs to use an atomic_t because the kexec and reboot code
(ab)use set_cpu_online() in their 'shutdown' handlers without any form of
serialization as pointed out by Mathieu. Regular CPU hotplug usage is
properly serialized.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1907091622590.1634@nanos.tec.linutronix.de
The booted once information which is required to deal with the MCE
broadcast issue on X86 correctly is stored in the per cpu hotplug state,
which is perfectly fine for the intended purpose.
X86 needs that information for supporting NMI broadcasting via shortcuts,
but retrieving it from per cpu data is cumbersome.
Move it to a cpumask so the information can be checked against the
cpu_present_mask quickly.
No functional change intended.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20190722105219.818822855@linutronix.de
Report the number of stack traces and the number of stack trace hash
chains. These two numbers are useful because these allow to estimate
the number of stack trace hash collisions.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20190722182443.216015-5-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Although commit 669de8bda8 ("kernel/workqueue: Use dynamic lockdep keys
for workqueues") unregisters dynamic lockdep keys when a workqueue is
destroyed, a side effect of that commit is that all stack traces
associated with the lockdep key are leaked when a workqueue is destroyed.
Fix this by storing each unique stack trace once. Other changes in this
patch are:
- Use NULL instead of { .nr_entries = 0 } to represent 'no trace'.
- Store a pointer to a stack trace in struct lock_class and struct
lock_list instead of storing 'nr_entries' and 'offset'.
This patch avoids that the following program triggers the "BUG:
MAX_STACK_TRACE_ENTRIES too low!" complaint:
#include <fcntl.h>
#include <unistd.h>
int main()
{
for (;;) {
int fd = open("/dev/infiniband/rdma_cm", O_RDWR);
close(fd);
}
}
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Reported-by: Eric Biggers <ebiggers@kernel.org>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Yuyang Du <duyuyang@gmail.com>
Link: https://lkml.kernel.org/r/20190722182443.216015-4-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Make it clear to humans and to the compiler that the stack trace
('entries') arguments are not modified.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20190722182443.216015-3-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch does not change the behavior of the lockdep code.
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Link: https://lkml.kernel.org/r/20190722182443.216015-2-bvanassche@acm.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Some hardware PMU drivers will override perf_event.cpu inside their
event_init callback. This causes a lockdep splat when initialized through
the kernel API:
WARNING: CPU: 0 PID: 250 at kernel/events/core.c:2917 ctx_sched_out+0x78/0x208
pc : ctx_sched_out+0x78/0x208
Call trace:
ctx_sched_out+0x78/0x208
__perf_install_in_context+0x160/0x248
remote_function+0x58/0x68
generic_exec_single+0x100/0x180
smp_call_function_single+0x174/0x1b8
perf_install_in_context+0x178/0x188
perf_event_create_kernel_counter+0x118/0x160
Fix this by calling perf_install_in_context with event->cpu, just like
perf_event_open
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Frank Li <Frank.li@nxp.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Link: https://lkml.kernel.org/r/c4ebe0503623066896d7046def4d6b1e06e0eb2e.1563972056.git.leonard.crestez@nxp.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
An uninitialized/ zeroed mutex will go unnoticed because there is no
check for it. There is a magic check in the unlock's slowpath path which
might go unnoticed if the unlock happens in the fastpath.
Add a ->magic check early in the mutex_lock() and mutex_trylock() path.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190703092125.lsdf4gpsh2plhavb@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
As Will Deacon points out, CONFIG_PROVE_LOCKING implies TRACE_IRQFLAGS,
so the conditions I added in the previous patch, and some others in the
same file can be simplified by only checking for the former.
No functional change.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Frederic Weisbecker <frederic@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Yuyang Du <duyuyang@gmail.com>
Fixes: 886532aee3 ("locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING")
Link: https://lkml.kernel.org/r/20190628102919.2345242-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The usage is now hidden in an #ifdef, so we need to move
the variable itself in there as well to avoid this warning:
kernel/locking/lockdep_proc.c:203:21: error: unused variable 'class' [-Werror,-Wunused-variable]
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Bart Van Assche <bvanassche@acm.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Qian Cai <cai@lca.pw>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <longman@redhat.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Yuyang Du <duyuyang@gmail.com>
Cc: frederic@kernel.org
Fixes: 68d41d8c94 ("locking/lockdep: Fix lock used or unused stats error")
Link: https://lkml.kernel.org/r/20190715092809.736834-1-arnd@arndb.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Since we just reviewed read_slowpath for ACQUIRE correctness, add a
few coments to retain our findings.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
While reviewing another read_slowpath patch, both Will and I noticed
another missing ACQUIRE, namely:
X = 0;
CPU0 CPU1
rwsem_down_read()
for (;;) {
set_current_state(TASK_UNINTERRUPTIBLE);
X = 1;
rwsem_up_write();
rwsem_mark_wake()
atomic_long_add(adjustment, &sem->count);
smp_store_release(&waiter->task, NULL);
if (!waiter.task)
break;
...
}
r = X;
Allows 'r == 0'.
Reported-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Will Deacon <will@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Will Deacon <will@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
LTP mtest06 has been observed to occasionally hit "still mapped when
deleted" and following BUG_ON on arm64.
The extra mapcount originated from pagefault handler, which handled
pagefault for vma that has already been detached. vma is detached
under mmap_sem write lock by detach_vmas_to_be_unmapped(), which
also invalidates vmacache.
When the pagefault handler (under mmap_sem read lock) calls
find_vma(), vmacache_valid() wrongly reports vmacache as valid.
After rwsem down_read() returns via 'queue empty' path (as of v5.2),
it does so without an ACQUIRE on sem->count:
down_read()
__down_read()
rwsem_down_read_failed()
__rwsem_down_read_failed_common()
raw_spin_lock_irq(&sem->wait_lock);
if (list_empty(&sem->wait_list)) {
if (atomic_long_read(&sem->count) >= 0) {
raw_spin_unlock_irq(&sem->wait_lock);
return sem;
The problem can be reproduced by running LTP mtest06 in a loop and
building the kernel (-j $NCPUS) in parallel. It does reproduces since
v4.20 on arm64 HPE Apollo 70 (224 CPUs, 256GB RAM, 2 nodes). It
triggers reliably in about an hour.
The patched kernel ran fine for 10+ hours.
Signed-off-by: Jan Stancek <jstancek@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Will Deacon <will@kernel.org>
Acked-by: Waiman Long <longman@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dbueso@suse.de
Fixes: 4b486b535c ("locking/rwsem: Exit read lock slowpath if queue empty & no writer")
Link: https://lkml.kernel.org/r/50b8914e20d1d62bb2dee42d342836c2c16ebee7.1563438048.git.jstancek@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
For writer, the owner value is cleared on unlock. For reader, it is
left intact on unlock for providing better debugging aid on crash dump
and the unlock of one reader may not mean the lock is free.
As a result, the owner_on_cpu() shouldn't be used on read-owner
as the task pointer value may not be valid and it might have
been freed. That is the case in rwsem_spin_on_owner(), but not in
rwsem_can_spin_on_owner(). This can lead to use-after-free error from
KASAN. For example,
BUG: KASAN: use-after-free in rwsem_down_write_slowpath
(/home/miguel/kernel/linux/kernel/locking/rwsem.c:669
/home/miguel/kernel/linux/kernel/locking/rwsem.c:1125)
Fix this by checking for RWSEM_READER_OWNED flag before calling
owner_on_cpu().
Reported-by: Luis Henriques <lhenriques@suse.com>
Tested-by: Luis Henriques <lhenriques@suse.com>
Signed-off-by: Waiman Long <longman@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: huang ying <huang.ying.caritas@gmail.com>
Fixes: 94a9717b3c ("locking/rwsem: Make rwsem->owner an atomic_long_t")
Link: https://lkml.kernel.org/r/81e82d5b-5074-77e8-7204-28479bbe0df0@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The old code used RCU annotations and accessors inconsistently for
->numa_group, which can lead to use-after-frees and NULL dereferences.
Let all accesses to ->numa_group use proper RCU helpers to prevent such
issues.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Fixes: 8c8a743c50 ("sched/numa: Use {cpu, pid} to create task groups for shared faults")
Link: https://lkml.kernel.org/r/20190716152047.14424-3-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When going through execve(), zero out the NUMA fault statistics instead of
freeing them.
During execve, the task is reachable through procfs and the scheduler. A
concurrent /proc/*/sched reader can read data from a freed ->numa_faults
allocation (confirmed by KASAN) and write it back to userspace.
I believe that it would also be possible for a use-after-free read to occur
through a race between a NUMA fault and execve(): task_numa_fault() can
lead to task_numa_compare(), which invokes task_weight() on the currently
running task of a different CPU.
Another way to fix this would be to make ->numa_faults RCU-managed or add
extra locking, but it seems easier to wipe the NUMA fault statistics on
execve.
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will@kernel.org>
Fixes: 82727018b0 ("sched/numa: Call task_numa_free() from do_execve()")
Link: https://lkml.kernel.org/r/20190716152047.14424-1-jannh@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
It turns out that 'access()' (and 'faccessat()') can cause a lot of RCU
work because it installs a temporary credential that gets allocated and
freed for each system call.
The allocation and freeing overhead is mostly benign, but because
credentials can be accessed under the RCU read lock, the freeing
involves a RCU grace period.
Which is not a huge deal normally, but if you have a lot of access()
calls, this causes a fair amount of seconday damage: instead of having a
nice alloc/free patterns that hits in hot per-CPU slab caches, you have
all those delayed free's, and on big machines with hundreds of cores,
the RCU overhead can end up being enormous.
But it turns out that all of this is entirely unnecessary. Exactly
because access() only installs the credential as the thread-local
subjective credential, the temporary cred pointer doesn't actually need
to be RCU free'd at all. Once we're done using it, we can just free it
synchronously and avoid all the RCU overhead.
So add a 'non_rcu' flag to 'struct cred', which can be set by users that
know they only use it in non-RCU context (there are other potential
users for this). We can make it a union with the rcu freeing list head
that we need for the RCU case, so this doesn't need any extra storage.
Note that this also makes 'get_current_cred()' clear the new non_rcu
flag, in case we have filesystems that take a long-term reference to the
cred and then expect the RCU delayed freeing afterwards. It's not
entirely clear that this is required, but it makes for clear semantics:
the subjective cred remains non-RCU as long as you only access it
synchronously using the thread-local accessors, but you _can_ use it as
a generic cred if you want to.
It is possible that we should just remove the whole RCU markings for
->cred entirely. Only ->real_cred is really supposed to be accessed
through RCU, and the long-term cred copies that nfs uses might want to
explicitly re-enable RCU freeing if required, rather than have
get_current_cred() do it implicitly.
But this is a "minimal semantic changes" change for the immediate
problem.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Eric Dumazet <edumazet@google.com>
Acked-by: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jan Glauber <jglauber@marvell.com>
Cc: Jiri Kosina <jikos@kernel.org>
Cc: Jayachandran Chandrasekharan Nair <jnair@marvell.com>
Cc: Greg KH <greg@kroah.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Check that the pfn returned from arch_dma_coherent_to_pfn refers to
a valid page and reject the mmap / get_sgtable requests otherwise.
Based on the arm implementation of the mmap and get_sgtable methods.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Vignesh Raghavendra <vigneshr@ti.com>
We could only handle the case that css exists
and css_try_get_online() fails.
Signed-off-by: Peng Wang <rocking@whu.edu.cn>
Signed-off-by: Tejun Heo <tj@kernel.org>
A string which did not contain a data format specification should be put
into a sequence. Thus use the corresponding function “seq_puts”.
This issue was detected by using the Coccinelle software.
Signed-off-by: Markus Elfring <elfring@users.sourceforge.net>
Signed-off-by: Tejun Heo <tj@kernel.org>
The very first check in test_pkt_md_access is failing on s390, which
happens because loading a part of a struct __sk_buff field produces
an incorrect result.
The preprocessed code of the check is:
{
__u8 tmp = *((volatile __u8 *)&skb->len +
((sizeof(skb->len) - sizeof(__u8)) / sizeof(__u8)));
if (tmp != ((*(volatile __u32 *)&skb->len) & 0xFF)) return 2;
};
clang generates the following code for it:
0: 71 21 00 03 00 00 00 00 r2 = *(u8 *)(r1 + 3)
1: 61 31 00 00 00 00 00 00 r3 = *(u32 *)(r1 + 0)
2: 57 30 00 00 00 00 00 ff r3 &= 255
3: 5d 23 00 1d 00 00 00 00 if r2 != r3 goto +29 <LBB0_10>
Finally, verifier transforms it to:
0: (61) r2 = *(u32 *)(r1 +104)
1: (bc) w2 = w2
2: (74) w2 >>= 24
3: (bc) w2 = w2
4: (54) w2 &= 255
5: (bc) w2 = w2
The problem is that when verifier emits the code to replace a partial
load of a struct __sk_buff field (*(u8 *)(r1 + 3)) with a full load of
struct sk_buff field (*(u32 *)(r1 + 104)), an optional shift and a
bitwise AND, it assumes that the machine is little endian and
incorrectly decides to use a shift.
Adjust shift count calculation to account for endianness.
Fixes: 31fd85816d ("bpf: permits narrower load from bpf program context fields")
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
After previous changes the suspend-to-idle code flow can be
integrated more tightly with the generic system suspend code flow
by making suspend_enter() call s2idle_loop() later and removing
the direct invocations of dpm_noirq_begin(),
dpm_noirq_suspend_devices(), dpm_noirq_end(), and
dpm_noirq_resume_devices() from the latter, so do that.
This change is not expected to alter functionality.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
After commit 33e4f80ee6 ("ACPI / PM: Ignore spurious SCI wakeups
from suspend-to-idle") the "noirq" phases of device suspend and
resume may run for multiple times during suspend-to-idle, if there
are spurious system wakeup events while suspended. However, this
is complicated and fragile and actually unnecessary.
The main reason for doing this is that on some systems the EC may
signal system wakeup events (power button events, for example) as
well as events that should not cause the system to resume (spurious
system wakeup events). Thus, in order to determine whether or not
a given event signaled by the EC while suspended is a proper system
wakeup one, the EC GPE needs to be dispatched and to start with that
was achieved by allowing the ACPI SCI action handler to run, which
was only possible after calling resume_device_irqs().
However, dispatching the EC GPE this way turned out to take too much
time in some cases and some EC events might be missed due to that, so
commit 68e2201185 ("ACPI: EC: Dispatch the EC GPE directly on
s2idle wake") started to dispatch the EC GPE right after a wakeup
event has been detected, so in fact the full ACPI SCI action handler
doesn't need to run any more to deal with the wakeups coming from the
EC.
Use this observation to simplify the suspend-to-idle control flow
so that the "noirq" phases of device suspend and resume are each
run only once in every suspend-to-idle cycle, which is reported to
significantly reduce power drawn by some systems when suspended to
idle (by allowing them to reach a deep platform-wide low-power state
through the suspend-to-idle flow). [What appears to happen is that
the "noirq" resume of devices after a spurious EC wakeup brings some
devices into a state in which they prevent the platform from reaching
the deep low-power state going forward, even after a subsequent
"noirq" suspend phase, and on some systems the EC triggers such
wakeups already when the "noirq" suspend of devices is running for
the first time in the given suspend/resume cycle, so the platform
cannot reach the deep low-power state at all.]
First, make acpi_s2idle_wake() use the acpi_ec_dispatch_gpe() return
value to determine whether or not the wakeup may have been triggered
by the EC (in which case the system wakeup is canceled and ACPI
events are processed in order to determine whether or not the event
is a proper system wakeup one) and use rearm_wake_irq() (introduced
by a previous change) in it to rearm the ACPI SCI for system wakeup
detection in case the system will remain suspended.
Second, drop acpi_s2idle_sync(), which is not needed any more, and
the corresponding global platform suspend-to-idle callback.
Next, drop the pm_wakeup_pending() check (which is an optimization
only) from __device_suspend_noirq() to prevent it from returning
errors on system wakeups occurring before the "noirq" phase of
device suspend is complete (as in the case of suspend-to-idle it is
not known whether or not these wakeups are suprious at that point),
in order to avoid having to carry out a "noirq" resume of devices
on a spurious system wakeup.
Finally, change the code flow in s2idle_loop() to (1) run the
"noirq" suspend of devices once before starting the loop, (2) check
for spurious EC wakeups (via the platform ->wake callback) for the
first time before calling s2idle_enter(), and (3) run the "noirq"
resume of devices once after leaving the loop.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Introduce a new function, rearm_wake_irq(), allowing a wakeup IRQ
to be armed for systen wakeup detection again without running any
action handlers associated with it after it has been armed for
wakeup detection and triggered.
That is useful for IRQs, like ACPI SCI, that may deliver wakeup
as well as non-wakeup interrupts when armed for systen wakeup
detection. In those cases, it may be possible to determine whether
or not the delivered interrupt is a systen wakeup one without
running the entire action handler (or handlers, if the IRQ is
shared) for the IRQ, and if the interrupt turns out to be a
non-wakeup one, the IRQ can be rearmed with the help of the
new function.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Pull preemption Kconfig fix from Thomas Gleixner:
"The PREEMPT_RT stub config renamed PREEMPT to PREEMPT_LL and defined
PREEMPT outside of the menu and made it selectable by both PREEMPT_LL
and PREEMPT_RT.
Stupid me missed that 114 defconfigs select CONFIG_PREEMPT which
obviously can't work anymore. oldconfig builds are affected as well,
but it's more obvious as the user gets asked. [old]defconfig silently
fixes it up and selects PREEMPT_NONE.
Unbreak it by undoing the rename and adding a intermediate config
symbol which is selected by both PREEMPT and PREEMPT_RT. That requires
to chase down a few #ifdefs, but it's better than tweaking 114
defconfigs and annoying users"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/rt, Kconfig: Unbreak def/oldconfig with CONFIG_PREEMPT=y
The merge of the CONFIG_PREEMPT_RT stub renamed CONFIG_PREEMPT to
CONFIG_PREEMPT_LL which causes all defconfigs which have CONFIG_PREEMPT=y
set to fall back to CONFIG_PREEMPT_NONE because CONFIG_PREEMPT depends on
the preemption mode choice wich defaults to NONE. This also affects
oldconfig builds.
So rather than changing 114 defconfig files and being an annoyance to
users, revert the rename and select a new config symbol PREEMPTION. That
keeps everything working smoothly and the revelant ifdef's are going to be
fixed up step by step.
Reported-by: Mark Rutland <mark.rutland@arm.com>
Fixes: a50a3f4b6a ("sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
There is a race between reading task->exit_state in pidfd_poll and
writing it after do_notify_parent calls do_notify_pidfd. Expected
sequence of events is:
CPU 0 CPU 1
------------------------------------------------
exit_notify
do_notify_parent
do_notify_pidfd
tsk->exit_state = EXIT_DEAD
pidfd_poll
if (tsk->exit_state)
However nothing prevents the following sequence:
CPU 0 CPU 1
------------------------------------------------
exit_notify
do_notify_parent
do_notify_pidfd
pidfd_poll
if (tsk->exit_state)
tsk->exit_state = EXIT_DEAD
This causes a polling task to wait forever, since poll blocks because
exit_state is 0 and the waiting task is not notified again. A stress
test continuously doing pidfd poll and process exits uncovered this bug.
To fix it, we make sure that the task's exit_state is always set before
calling do_notify_pidfd.
Fixes: b53b0b9d9a ("pidfd: add polling support")
Cc: kernel-team@android.com
Cc: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lore.kernel.org/r/20190717172100.261204-1-joel@joelfernandes.org
[christian@brauner.io: adapt commit message and drop unneeded changes from wait_task_zombie]
Signed-off-by: Christian Brauner <christian@brauner.io>
MPX is being removed from the kernel due to a lack of support in the
toolchain going forward (gcc).
The first step is to remove the userspace-visible ABIs so that applications
will stop using it. The most visible one are the enable/disable prctl()s.
Remove them first.
This is the most minimal and least invasive change needed to ensure that
apps stop using MPX with new kernels.
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190705175321.DB42F0AD@viggo.jf.intel.com
Fix various regressions:
- force unencrypted dma-coherent buffers if encryption bit can't fit
into the dma coherent mask (Tom Lendacky)
- avoid limiting request size if swiotlb is not used (me)
- fix swiotlb handling in dma_direct_sync_sg_for_cpu/device
(Fugang Duan)
-----BEGIN PGP SIGNATURE-----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=Bv+Q
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
"Fix various regressions:
- force unencrypted dma-coherent buffers if encryption bit can't fit
into the dma coherent mask (Tom Lendacky)
- avoid limiting request size if swiotlb is not used (me)
- fix swiotlb handling in dma_direct_sync_sg_for_cpu/device (Fugang
Duan)"
* tag 'dma-mapping-5.3-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-direct: correct the physical addr in dma_direct_sync_sg_for_cpu/device
dma-direct: only limit the mapping size if swiotlb could be used
dma-mapping: add a dma_addressing_limited helper
dma-direct: Force unencrypted DMA under SME for certain DMA masks
Pull core fixes from Thomas Gleixner:
- A collection of objtool fixes which address recent fallout partially
exposed by newer toolchains, clang, BPF and general code changes.
- Force USER_DS for user stack traces
[ Note: the "objtool fixes" are not all to objtool itself, but for
kernel code that triggers objtool warnings.
Things like missing function size annotations, or code that confuses
the unwinder etc. - Linus]
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (27 commits)
objtool: Support conditional retpolines
objtool: Convert insn type to enum
objtool: Fix seg fault on bad switch table entry
objtool: Support repeated uses of the same C jump table
objtool: Refactor jump table code
objtool: Refactor sibling call detection logic
objtool: Do frame pointer check before dead end check
objtool: Change dead_end_function() to return boolean
objtool: Warn on zero-length functions
objtool: Refactor function alias logic
objtool: Track original function across branches
objtool: Add mcsafe_handle_tail() to the uaccess safe list
bpf: Disable GCC -fgcse optimization for ___bpf_prog_run()
x86/uaccess: Remove redundant CLACs in getuser/putuser error paths
x86/uaccess: Don't leak AC flag into fentry from mcsafe_handle_tail()
x86/uaccess: Remove ELF function annotation from copy_user_handle_tail()
x86/head/64: Annotate start_cpu0() as non-callable
x86/entry: Fix thunk function ELF sizes
x86/kvm: Don't call kvm_spurious_fault() from .fixup
x86/kvm: Replace vmx_vmenter()'s call to kvm_spurious_fault() with UD2
...
Pull smp fix from Thomas Gleixner:
"Add warnings to the smp function calls so callers from wrong contexts
get detected"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp: Warn on function calls from softirq context
Pull CONFIG_PREEMPT_RT stub config from Thomas Gleixner:
"The real-time preemption patch set exists for almost 15 years now and
while the vast majority of infrastructure and enhancements have found
their way into the mainline kernel, the final integration of RT is
still missing.
Over the course of the last few years, we have worked on reducing the
intrusivenness of the RT patches by refactoring kernel infrastructure
to be more real-time friendly. Almost all of these changes were
benefitial to the mainline kernel on their own, so there was no
objection to integrate them.
Though except for the still ongoing printk refactoring, the remaining
changes which are required to make RT a first class mainline citizen
are not longer arguable as immediately beneficial for the mainline
kernel. Most of them are either reordering code flows or adding RT
specific functionality.
But this now has hit a wall and turned into a classic hen and egg
problem:
Maintainers are rightfully wary vs. these changes as they make only
sense if the final integration of RT into the mainline kernel takes
place.
Adding CONFIG_PREEMPT_RT aims to solve this as a clear sign that RT
will be fully integrated into the mainline kernel. The final
integration of the missing bits and pieces will be of course done with
the same careful approach as we have used in the past.
While I'm aware that you are not entirely enthusiastic about that, I
think that RT should receive the same treatment as any other widely
used out of tree functionality, which we have accepted into mainline
over the years.
RT has become the de-facto standard real-time enhancement and is
shipped by enterprise, embedded and community distros. It's in use
throughout a wide range of industries: telecommunications, industrial
automation, professional audio, medical devices, data acquisition,
automotive - just to name a few major use cases.
RT development is backed by a Linuxfoundation project which is
supported by major stakeholders of this technology. The funding will
continue over the actual inclusion into mainline to make sure that the
functionality is neither introducing regressions, regressing itself,
nor becomes subject to bitrot. There is also a lifely user community
around RT as well, so contrary to the grim situation 5 years ago, it's
a healthy project.
As RT is still a good vehicle to exercise rarely used code paths and
to detect hard to trigger issues, you could at least view it as a QA
tool if nothing else"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/rt, Kconfig: Introduce CONFIG_PREEMPT_RT
- s390 support for KVM selftests
- LAPIC timer offloading to housekeeping CPUs
- Extend an s390 optimization for overcommitted hosts to all architectures
- Debugging cleanups and improvements
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
iQEcBAABAgAGBQJdMr1FAAoJEL/70l94x66DvIkH/iVuUX9jO1NoQ7qhxeo04MnT
GP9mX3XnWoI/iN0zAIRfQSP2/9a6+KblgdiziABhju58j5dCfAZGb5793TQppweb
3ubl11vy7YkzaXJ0b35K7CFhOU9oSlHHGyi5Uh+yyje5qWNxwmHpizxjynbFTKb6
+/S7O2Ua1VrAVvx0i0IRtwanIK/jF4dStVButgVaVdUva3zLaQmeI71iaJl9ddXY
bh50xoYua5Ek6+ENi+nwCNVy4OF152AwDbXlxrU0QbeA1B888Qio7nIqb3bwwPpZ
/8wMVvPzQgL7RmgtY5E5Z4cCYuu7mK8wgGxhuk3oszlVwZJ5rmnaYwGEl4x1s7o=
=giag
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull more KVM updates from Paolo Bonzini:
"Mostly bugfixes, but also:
- s390 support for KVM selftests
- LAPIC timer offloading to housekeeping CPUs
- Extend an s390 optimization for overcommitted hosts to all
architectures
- Debugging cleanups and improvements"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (25 commits)
KVM: x86: Add fixed counters to PMU filter
KVM: nVMX: do not use dangling shadow VMCS after guest reset
KVM: VMX: dump VMCS on failed entry
KVM: x86/vPMU: refine kvm_pmu err msg when event creation failed
KVM: s390: Use kvm_vcpu_wake_up in kvm_s390_vcpu_wakeup
KVM: Boost vCPUs that are delivering interrupts
KVM: selftests: Remove superfluous define from vmx.c
KVM: SVM: Fix detection of AMD Errata 1096
KVM: LAPIC: Inject timer interrupt via posted interrupt
KVM: LAPIC: Make lapic timer unpinned
KVM: x86/vPMU: reset pmc->counter to 0 for pmu fixed_counters
KVM: nVMX: Ignore segment base for VMX memory operand when segment not FS or GS
kvm: x86: ioapic and apic debug macros cleanup
kvm: x86: some tsc debug cleanup
kvm: vmx: fix coccinelle warnings
x86: kvm: avoid constant-conversion warning
x86: kvm: avoid -Wsometimes-uninitized warning
KVM: x86: expose AVX512_BF16 feature to guest
KVM: selftests: enable pgste option for the linker on s390
KVM: selftests: Move kvm_create_max_vcpus test to generic code
...
It's clearly documented that smp function calls cannot be invoked from
softirq handling context. Unfortunately nothing enforces that or emits a
warning.
A single function call can be invoked from softirq context only via
smp_call_function_single_async().
The only legit context is task context, so add a warning to that effect.
Reported-by: luferry <luferry@163.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20190718160601.GP3402@hirez.programming.kicks-ass.net
Dedicated instances are currently disturbed by unnecessary jitter due
to the emulated lapic timers firing on the same pCPUs where the
vCPUs reside. There is no hardware virtual timer on Intel for guest
like ARM, so both programming timer in guest and the emulated timer fires
incur vmexits. This patch tries to avoid vmexit when the emulated timer
fires, at least in dedicated instance scenario when nohz_full is enabled.
In that case, the emulated timers can be offload to the nearest busy
housekeeping cpus since APICv has been found for several years in server
processors. The guest timer interrupt can then be injected via posted interrupts,
which are delivered by the housekeeping cpu once the emulated timer fires.
The host should tuned so that vCPUs are placed on isolated physical
processors, and with several pCPUs surplus for busy housekeeping.
If disabled mwait/hlt/pause vmexits keep the vCPUs in non-root mode,
~3% redis performance benefit can be observed on Skylake server, and the
number of external interrupt vmexits drops substantially. Without patch
VM-EXIT Samples Samples% Time% Min Time Max Time Avg time
EXTERNAL_INTERRUPT 42916 49.43% 39.30% 0.47us 106.09us 0.71us ( +- 1.09% )
While with patch:
VM-EXIT Samples Samples% Time% Min Time Max Time Avg time
EXTERNAL_INTERRUPT 6871 9.29% 2.96% 0.44us 57.88us 0.72us ( +- 4.02% )
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krčmář <rkrcmar@redhat.com>
Cc: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Wanpeng Li <wanpengli@tencent.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Pull crypto fixes from Herbert Xu:
- Fix missed wake-up race in padata
- Use crypto_memneq in ccp
- Fix version check in ccp
- Fix fuzz test failure in ccp
- Fix potential double free in crypto4xx
- Fix compile warning in stm32
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
padata: use smp_mb in padata_reorder to avoid orphaned padata jobs
crypto: ccp - Fix SEV_VERSION_GREATER_OR_EQUAL
crypto: ccp/gcm - use const time tag comparison.
crypto: ccp - memset structure fields to zero before reuse
crypto: crypto4xx - fix a potential double free in ppc4xx_trng_probe
crypto: stm32/hash - Fix incorrect printk modifier for size_t
Removing ULONG_MAX as the marker for the user stack trace end,
made the tracing code not know where the end is. The end is now
marked with a zero (NULL) pointer. Eiichi fixed this in the tracing
code.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXTHsuRQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qgETAQDqRtu1KhJM6ujNlPY1aw6e9ncDAqWn
6GaumMgAdBqEcAEAxJSjr5UlzXuJsCjUjwE0txLfTscyNwljKW77h4/WNwA=
=bwtH
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fix from Steven Rostedt:
"Eiichi Tsukata found a small bug from the fixup of the stack code
Removing ULONG_MAX as the marker for the user stack trace end, made
the tracing code not know where the end is. The end is now marked with
a zero (NULL) pointer. Eiichi fixed this in the tracing code"
* tag 'trace-v5.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
tracing: Fix user stack trace "??" output
Pull vfs mount updates from Al Viro:
"The first part of mount updates.
Convert filesystems to use the new mount API"
* 'work.mount0' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
mnt_init(): call shmem_init() unconditionally
constify ksys_mount() string arguments
don't bother with registering rootfs
init_rootfs(): don't bother with init_ramfs_fs()
vfs: Convert smackfs to use the new mount API
vfs: Convert selinuxfs to use the new mount API
vfs: Convert securityfs to use the new mount API
vfs: Convert apparmorfs to use the new mount API
vfs: Convert openpromfs to use the new mount API
vfs: Convert xenfs to use the new mount API
vfs: Convert gadgetfs to use the new mount API
vfs: Convert oprofilefs to use the new mount API
vfs: Convert ibmasmfs to use the new mount API
vfs: Convert qib_fs/ipathfs to use the new mount API
vfs: Convert efivarfs to use the new mount API
vfs: Convert configfs to use the new mount API
vfs: Convert binfmt_misc to use the new mount API
convenience helper: get_tree_single()
convenience helper get_tree_nodev()
vfs: Kill sget_userns()
...
Pull networking fixes from David Miller:
1) Fix AF_XDP cq entry leak, from Ilya Maximets.
2) Fix handling of PHY power-down on RTL8411B, from Heiner Kallweit.
3) Add some new PCI IDs to iwlwifi, from Ihab Zhaika.
4) Fix handling of neigh timers wrt. entries added by userspace, from
Lorenzo Bianconi.
5) Various cases of missing of_node_put(), from Nishka Dasgupta.
6) The new NET_ACT_CT needs to depend upon NF_NAT, from Yue Haibing.
7) Various RDS layer fixes, from Gerd Rausch.
8) Fix some more fallout from TCQ_F_CAN_BYPASS generalization, from
Cong Wang.
9) Fix FIB source validation checks over loopback, also from Cong Wang.
10) Use promisc for unsupported number of filters, from Justin Chen.
11) Missing sibling route unlink on failure in ipv6, from Ido Schimmel.
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (90 commits)
tcp: fix tcp_set_congestion_control() use from bpf hook
ag71xx: fix return value check in ag71xx_probe()
ag71xx: fix error return code in ag71xx_probe()
usb: qmi_wwan: add D-Link DWM-222 A2 device ID
bnxt_en: Fix VNIC accounting when enabling aRFS on 57500 chips.
net: dsa: sja1105: Fix missing unlock on error in sk_buff()
gve: replace kfree with kvfree
selftests/bpf: fix test_xdp_noinline on s390
selftests/bpf: fix "valid read map access into a read-only array 1" on s390
net/mlx5: Replace kfree with kvfree
MAINTAINERS: update netsec driver
ipv6: Unlink sibling route in case of failure
liquidio: Replace vmalloc + memset with vzalloc
udp: Fix typo in net/ipv4/udp.c
net: bcmgenet: use promisc for unsupported filters
ipv6: rt6_check should return NULL if 'from' is NULL
tipc: initialize 'validated' field of received packets
selftests: add a test case for rp_filter
fib: relax source validation check for loopback packets
mlxsw: spectrum: Do not process learned records with a dummy FID
...
Merge yet more updates from Andrew Morton:
"The rest of MM and a kernel-wide procfs cleanup.
Summary of the more significant patches:
- Patch series "mm/memory_hotplug: Factor out memory block
devicehandling", v3. David Hildenbrand.
Some spring-cleaning of the memory hotplug code, notably in
drivers/base/memory.c
- "mm: thp: fix false negative of shmem vma's THP eligibility". Yang
Shi.
Fix /proc/pid/smaps output for THP pages used in shmem.
- "resource: fix locking in find_next_iomem_res()" + 1. Nadav Amit.
Bugfix and speedup for kernel/resource.c
- Patch series "mm: Further memory block device cleanups", David
Hildenbrand.
More spring-cleaning of the memory hotplug code.
- Patch series "mm: Sub-section memory hotplug support". Dan
Williams.
Generalise the memory hotplug code so that pmem can use it more
completely. Then remove the hacks from the libnvdimm code which
were there to work around the memory-hotplug code's constraints.
- "proc/sysctl: add shared variables for range check", Matteo Croce.
We have about 250 instances of
int zero;
...
.extra1 = &zero,
in the tree. This is a tree-wide sweep to make all those private
"zero"s and "one"s use global variables.
Alas, it isn't practical to make those two global integers const"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (38 commits)
proc/sysctl: add shared variables for range check
mm: migrate: remove unused mode argument
mm/sparsemem: cleanup 'section number' data types
libnvdimm/pfn: stop padding pmem namespaces to section alignment
libnvdimm/pfn: fix fsdax-mode namespace info-block zero-fields
mm/devm_memremap_pages: enable sub-section remap
mm: document ZONE_DEVICE memory-model implications
mm/sparsemem: support sub-section hotplug
mm/sparsemem: prepare for sub-section ranges
mm: kill is_dev_zone() helper
mm/hotplug: kill is_dev_zone() usage in __remove_pages()
mm/sparsemem: convert kmalloc_section_memmap() to populate_section_memmap()
mm/hotplug: prepare shrink_{zone, pgdat}_span for sub-section removal
mm/sparsemem: add helpers track active portions of a section at boot
mm/sparsemem: introduce a SECTION_IS_EARLY flag
mm/sparsemem: introduce struct mem_section_usage
drivers/base/memory.c: get rid of find_memory_block_hinted()
mm/memory_hotplug: move and simplify walk_memory_blocks()
mm/memory_hotplug: rename walk_memory_range() and pass start+size instead of pfns
mm: make register_mem_sect_under_node() static
...
Commit c5c27a0a58 ("x86/stacktrace: Remove the pointless ULONG_MAX
marker") removes ULONG_MAX marker from user stack trace entries but
trace_user_stack_print() still uses the marker and it outputs unnecessary
"??".
For example:
less-1911 [001] d..2 34.758944: <user stack trace>
=> <00007f16f2295910>
=> ??
=> ??
=> ??
=> ??
=> ??
=> ??
=> ??
The user stack trace code zeroes the storage before saving the stack, so if
the trace is shorter than the maximum number of entries it can terminate
the print loop if a zero entry is detected.
Link: http://lkml.kernel.org/r/20190630085438.25545-1-devel@etsukata.com
Cc: stable@vger.kernel.org
Fixes: 4285f2fcef ("tracing: Remove the ULONG_MAX stack trace hackery")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
dma_map_sg() may use swiotlb buffer when the kernel command line includes
"swiotlb=force" or the dma_addr is out of dev->dma_mask range. After
DMA complete the memory moving from device to memory, then user call
dma_sync_sg_for_cpu() to sync with DMA buffer, and copy the original
virtual buffer to other space.
So dma_direct_sync_sg_for_cpu() should use swiotlb physical addr, not
the original physical addr from sg_phys(sg).
dma_direct_sync_sg_for_device() also has the same issue, correct it as
well.
Fixes: 55897af63091("dma-direct: merge swiotlb_dma_ops into the dma_direct code")
Signed-off-by: Fugang Duan <fugang.duan@nxp.com>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
In the sysctl code the proc_dointvec_minmax() function is often used to
validate the user supplied value between an allowed range. This
function uses the extra1 and extra2 members from struct ctl_table as
minimum and maximum allowed value.
On sysctl handler declaration, in every source file there are some
readonly variables containing just an integer which address is assigned
to the extra1 and extra2 members, so the sysctl range is enforced.
The special values 0, 1 and INT_MAX are very often used as range
boundary, leading duplication of variables like zero=0, one=1,
int_max=INT_MAX in different source files:
$ git grep -E '\.extra[12].*&(zero|one|int_max)' |wc -l
248
Add a const int array containing the most commonly used values, some
macros to refer more easily to the correct array member, and use them
instead of creating a local one for every object file.
This is the bloat-o-meter output comparing the old and new binary
compiled with the default Fedora config:
# scripts/bloat-o-meter -d vmlinux.o.old vmlinux.o
add/remove: 2/2 grow/shrink: 0/2 up/down: 24/-188 (-164)
Data old new delta
sysctl_vals - 12 +12
__kstrtab_sysctl_vals - 12 +12
max 14 10 -4
int_max 16 - -16
one 68 - -68
zero 128 28 -100
Total: Before=20583249, After=20583085, chg -0.00%
[mcroce@redhat.com: tipc: remove two unused variables]
Link: http://lkml.kernel.org/r/20190530091952.4108-1-mcroce@redhat.com
[akpm@linux-foundation.org: fix net/ipv6/sysctl_net_ipv6.c]
[arnd@arndb.de: proc/sysctl: make firmware loader table conditional]
Link: http://lkml.kernel.org/r/20190617130014.1713870-1-arnd@arndb.de
[akpm@linux-foundation.org: fix fs/eventpoll.c]
Link: http://lkml.kernel.org/r/20190430180111.10688-1-mcroce@redhat.com
Signed-off-by: Matteo Croce <mcroce@redhat.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Aaron Tomlin <atomlin@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Teach devm_memremap_pages() about the new sub-section capabilities of
arch_{add,remove}_memory(). Effectively, just replace all usage of
align_start, align_end, and align_size with res->start, res->end, and
resource_size(res). The existing sanity check will still make sure that
the two separate remap attempts do not collide within a sub-section (2MB
on x86).
Link: http://lkml.kernel.org/r/156092355542.979959.10060071713397030576.stgit@dwillia2-desk3.amr.corp.intel.com
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com> [ppc64]
Cc: Michal Hocko <mhocko@suse.com>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Jérôme Glisse <jglisse@redhat.com>
Cc: Logan Gunthorpe <logang@deltatee.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Pavel Tatashin <pasha.tatashin@soleen.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Jane Chu <jane.chu@oracle.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Wei Yang <richardw.yang@linux.intel.com>
Cc: Jason Gunthorpe <jgg@mellanox.com>
Cc: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
find_next_iomem_res() shows up to be a source for overhead in dax
benchmarks.
Improve performance by not considering children of the tree if the top
level does not match. Since the range of the parents should include the
range of the children such check is redundant.
Running sysbench on dax (pmem emulation, with write_cache disabled):
sysbench fileio --file-total-size=3G --file-test-mode=rndwr \
--file-io-mode=mmap --threads=4 --file-fsync-mode=fdatasync run
Provides the following results:
events (avg/stddev)
-------------------
5.2-rc3: 1247669.0000/16075.39
w/patch: 1286320.5000/16402.72 (+3%)
Link: http://lkml.kernel.org/r/20190613045903.4922-3-namit@vmware.com
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since resources can be removed, locking should ensure that the resource
is not removed while accessing it. However, find_next_iomem_res() does
not hold the lock while copying the data of the resource.
Keep holding the lock while the data is copied. While at it, change the
return value to a more informative value. It is disregarded by the
callers.
[akpm@linux-foundation.org: fix find_next_iomem_res() documentation]
Link: http://lkml.kernel.org/r/20190613045903.4922-2-namit@vmware.com
Fixes: ff3cc952d3 ("resource: Add remove_resource interface")
Signed-off-by: Nadav Amit <namit@vmware.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Toshi Kani <toshi.kani@hpe.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a new entry to the preemption menu which enables the real-time support
for the kernel. The choice is only enabled when an architecture supports
it.
It selects PREEMPT as the RT features depend on it. To achieve that the
existing PREEMPT choice is renamed to PREEMPT_LL which select PREEMPT as
well.
No functional change.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Paul E. McKenney <paulmck@linux.ibm.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Clark Williams <williams@redhat.com>
Acked-by: Daniel Bristot de Oliveira <bristot@redhat.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Marc Zyngier <marc.zyngier@arm.com>
Acked-by: Daniel Wagner <wagi@monom.org>
Acked-by: Luis Claudio R. Goncalves <lgoncalv@redhat.com>
Acked-by: Julia Cartwright <julia@ni.com>
Acked-by: Tom Zanussi <tom.zanussi@linux.intel.com>
Acked-by: Gratian Crisan <gratian.crisan@ni.com>
Acked-by: Sebastian Siewior <bigeasy@linutronix.de>
Cc: Andrew Morton <akpm@linuxfoundation.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Lukas Bulwahn <lukas.bulwahn@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/alpine.DEB.2.21.1907172200190.1778@nanos.tec.linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Alexei Starovoitov says:
====================
pull-request: bpf 2019-07-18
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) verifier precision propagation fix, from Andrii.
2) BTF size fix for typedefs, from Andrii.
3) a bunch of big endian fixes, from Ilya.
4) wide load from bpf_sock_addr fixes, from Stanislav.
5) a bunch of misc fixes from a number of developers.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Summary of modules changes for the 5.3 merge window:
- Code fixes and cleanups
- Fix bug where set_memory_x() wasn't being called when rodata=n
- Fix bug where -EEXIST was being returned for going modules
- Allow arches to override module_exit_section()
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-----BEGIN PGP SIGNATURE-----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=/sk3
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"Summary of modules changes for the 5.3 merge window:
- Code fixes and cleanups
- Fix bug where set_memory_x() wasn't being called when rodata=n
- Fix bug where -EEXIST was being returned for going modules
- Allow arches to override module_exit_section()"
* tag 'modules-for-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
modules: fix compile error if don't have strict module rwx
ARM: module: recognize unwind exit sections
module: allow arch overrides for .exit section names
modules: fix BUG when load module with rodata=n
kernel/module: Fix mem leak in module_add_modinfo_attrs
kernel: module: Use struct_size() helper
kernel/module.c: Only return -EEXIST for modules that have finished loading
On x86-64, with CONFIG_RETPOLINE=n, GCC's "global common subexpression
elimination" optimization results in ___bpf_prog_run()'s jumptable code
changing from this:
select_insn:
jmp *jumptable(, %rax, 8)
...
ALU64_ADD_X:
...
jmp *jumptable(, %rax, 8)
ALU_ADD_X:
...
jmp *jumptable(, %rax, 8)
to this:
select_insn:
mov jumptable, %r12
jmp *(%r12, %rax, 8)
...
ALU64_ADD_X:
...
jmp *(%r12, %rax, 8)
ALU_ADD_X:
...
jmp *(%r12, %rax, 8)
The jumptable address is placed in a register once, at the beginning of
the function. The function execution can then go through multiple
indirect jumps which rely on that same register value. This has a few
issues:
1) Objtool isn't smart enough to be able to track such a register value
across multiple recursive indirect jumps through the jump table.
2) With CONFIG_RETPOLINE enabled, this optimization actually results in
a small slowdown. I measured a ~4.7% slowdown in the test_bpf
"tcpdump port 22" selftest.
This slowdown is actually predicted by the GCC manual:
Note: When compiling a program using computed gotos, a GCC
extension, you may get better run-time performance if you
disable the global common subexpression elimination pass by
adding -fno-gcse to the command line.
So just disable the optimization for this function.
Fixes: e55a73251d ("bpf: Fix ORC unwinding in non-JIT BPF code")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/30c3ca29ba037afcbd860a8672eef0021addf9fe.1563413318.git.jpoimboe@redhat.com
- Add user space specific memory reading for kprobes
- Allow kprobes to be executed earlier in boot
The rest are mostly just various clean ups and small fixes.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXS88txQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qhaPAQDHaAmu6wXtZjZE6GU4ZP61UNgDECmZ
4wlGrNc1AAlqAQD/QC8339p37aDCp9n27VY1wmJwF3nca+jAHfQLqWkkYgw=
=n/tz
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
"The main changes in this release include:
- Add user space specific memory reading for kprobes
- Allow kprobes to be executed earlier in boot
The rest are mostly just various clean ups and small fixes"
* tag 'trace-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (33 commits)
tracing: Make trace_get_fields() global
tracing: Let filter_assign_type() detect FILTER_PTR_STRING
tracing: Pass type into tracing_generic_entry_update()
ftrace/selftest: Test if set_event/ftrace_pid exists before writing
ftrace/selftests: Return the skip code when tracing directory not configured in kernel
tracing/kprobe: Check registered state using kprobe
tracing/probe: Add trace_event_call accesses APIs
tracing/probe: Add probe event name and group name accesses APIs
tracing/probe: Add trace flag access APIs for trace_probe
tracing/probe: Add trace_event_file access APIs for trace_probe
tracing/probe: Add trace_event_call register API for trace_probe
tracing/probe: Add trace_probe init and free functions
tracing/uprobe: Set print format when parsing command
tracing/kprobe: Set print format right after parsed command
kprobes: Fix to init kprobes in subsys_initcall
tracepoint: Use struct_size() in kmalloc()
ring-buffer: Remove HAVE_64BIT_ALIGNED_ACCESS
ftrace: Enable trampoline when rec count returns back to one
tracing/kprobe: Do not run kprobe boot tests if kprobe_event is on cmdline
tracing: Make a separate config for trace event self tests
...
Pull swiotlb updates from Konrad Rzeszutek Wilk:
"One compiler fix, and a bug-fix in swiotlb_nr_tbl() and
swiotlb_max_segment() to check also for no_iotlb_memory"
* 'for-linus-5.2' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb:
swiotlb: fix phys_addr_t overflow warning
swiotlb: Return consistent SWIOTLB segments/nr_tbl
swiotlb: Group identical cleanup in swiotlb_cleanup()
When walking userspace stacks, USER_DS needs to be set, otherwise
access_ok() will not function as expected.
Reported-by: Vegard Nossum <vegard.nossum@oracle.com>
Reported-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Vegard Nossum <vegard.nossum@oracle.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Link: https://lkml.kernel.org/r/20190718085754.GM3402@hirez.programming.kicks-ass.net
Testing padata with the tcrypt module on a 5.2 kernel...
# modprobe tcrypt alg="pcrypt(rfc4106(gcm(aes)))" type=3
# modprobe tcrypt mode=211 sec=1
...produces this splat:
INFO: task modprobe:10075 blocked for more than 120 seconds.
Not tainted 5.2.0-base+ #16
modprobe D 0 10075 10064 0x80004080
Call Trace:
? __schedule+0x4dd/0x610
? ring_buffer_unlock_commit+0x23/0x100
schedule+0x6c/0x90
schedule_timeout+0x3b/0x320
? trace_buffer_unlock_commit_regs+0x4f/0x1f0
wait_for_common+0x160/0x1a0
? wake_up_q+0x80/0x80
{ crypto_wait_req } # entries in braces added by hand
{ do_one_aead_op }
{ test_aead_jiffies }
test_aead_speed.constprop.17+0x681/0xf30 [tcrypt]
do_test+0x4053/0x6a2b [tcrypt]
? 0xffffffffa00f4000
tcrypt_mod_init+0x50/0x1000 [tcrypt]
...
The second modprobe command never finishes because in padata_reorder,
CPU0's load of reorder_objects is executed before the unlocking store in
spin_unlock_bh(pd->lock), causing CPU0 to miss CPU1's increment:
CPU0 CPU1
padata_reorder padata_do_serial
LOAD reorder_objects // 0
INC reorder_objects // 1
padata_reorder
TRYLOCK pd->lock // failed
UNLOCK pd->lock
CPU0 deletes the timer before returning from padata_reorder and since no
other job is submitted to padata, modprobe waits indefinitely.
Add a pair of full barriers to guarantee proper ordering:
CPU0 CPU1
padata_reorder padata_do_serial
UNLOCK pd->lock
smp_mb()
LOAD reorder_objects
INC reorder_objects
smp_mb__after_atomic()
padata_reorder
TRYLOCK pd->lock
smp_mb__after_atomic is needed so the read part of the trylock operation
comes after the INC, as Andrea points out. Thanks also to Andrea for
help with writing a litmus test.
Fixes: 16295bec63 ("padata: Generic parallelization/serialization interface")
Signed-off-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: <stable@vger.kernel.org>
Cc: Andrea Parri <andrea.parri@amarulasolutions.com>
Cc: Boqun Feng <boqun.feng@gmail.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Paul E. McKenney <paulmck@linux.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: linux-arch@vger.kernel.org
Cc: linux-crypto@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Merge more updates from Andrew Morton:
"VM:
- z3fold fixes and enhancements by Henry Burns and Vitaly Wool
- more accurate reclaimed slab caches calculations by Yafang Shao
- fix MAP_UNINITIALIZED UAPI symbol to not depend on config, by
Christoph Hellwig
- !CONFIG_MMU fixes by Christoph Hellwig
- new novmcoredd parameter to omit device dumps from vmcore, by
Kairui Song
- new test_meminit module for testing heap and pagealloc
initialization, by Alexander Potapenko
- ioremap improvements for huge mappings, by Anshuman Khandual
- generalize kprobe page fault handling, by Anshuman Khandual
- device-dax hotplug fixes and improvements, by Pavel Tatashin
- enable synchronous DAX fault on powerpc, by Aneesh Kumar K.V
- add pte_devmap() support for arm64, by Robin Murphy
- unify locked_vm accounting with a helper, by Daniel Jordan
- several misc fixes
core/lib:
- new typeof_member() macro including some users, by Alexey Dobriyan
- make BIT() and GENMASK() available in asm, by Masahiro Yamada
- changed LIST_POISON2 on x86_64 to 0xdead000000000122 for better
code generation, by Alexey Dobriyan
- rbtree code size optimizations, by Michel Lespinasse
- convert struct pid count to refcount_t, by Joel Fernandes
get_maintainer.pl:
- add --no-moderated switch to skip moderated ML's, by Joe Perches
misc:
- ptrace PTRACE_GET_SYSCALL_INFO interface
- coda updates
- gdb scripts, various"
[ Using merge message suggestion from Vlastimil Babka, with some editing - Linus ]
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (100 commits)
fs/select.c: use struct_size() in kmalloc()
mm: add account_locked_vm utility function
arm64: mm: implement pte_devmap support
mm: introduce ARCH_HAS_PTE_DEVMAP
mm: clean up is_device_*_page() definitions
mm/mmap: move common defines to mman-common.h
mm: move MAP_SYNC to asm-generic/mman-common.h
device-dax: "Hotremove" persistent memory that is used like normal RAM
mm/hotplug: make remove_memory() interface usable
device-dax: fix memory and resource leak if hotplug fails
include/linux/lz4.h: fix spelling and copy-paste errors in documentation
ipc/mqueue.c: only perform resource calculation if user valid
include/asm-generic/bug.h: fix "cut here" for WARN_ON for __WARN_TAINT architectures
scripts/gdb: add helpers to find and list devices
scripts/gdb: add lx-genpd-summary command
drivers/pps/pps.c: clear offset flags in PPS_SETPARAMS ioctl
kernel/pid.c: convert struct pid count to refcount_t
drivers/rapidio/devices/rio_mport_cdev.c: NUL terminate some strings
select: shift restore_saved_sigmask_unless() into poll_select_copy_remaining()
select: change do_poll() to return -ERESTARTNOHAND rather than -EINTR
...
Don't just check for a swiotlb buffer, but also if buffering might
be required for this particular device.
Fixes: 133d624b1c ("dma: Introduce dma_max_mapping_size()")
Reported-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
struct pid's count is an atomic_t field used as a refcount. Use
refcount_t for it which is basically atomic_t but does additional
checking to prevent use-after-free bugs.
For memory ordering, the only change is with the following:
- if ((atomic_read(&pid->count) == 1) ||
- atomic_dec_and_test(&pid->count)) {
+ if (refcount_dec_and_test(&pid->count)) {
kmem_cache_free(ns->pid_cachep, pid);
Here the change is from: Fully ordered --> RELEASE + ACQUIRE (as per
refcount-vs-atomic.rst) This ACQUIRE should take care of making sure the
free happens after the refcount_dec_and_test().
The above hunk also removes atomic_read() since it is not needed for the
code to work and it is unclear how beneficial it is. The removal lets
refcount_dec_and_test() check for cases where get_pid() happened before
the object was freed.
Link: http://lkml.kernel.org/r/20190701183826.191936-1-joel@joelfernandes.org
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: Andrea Parri <andrea.parri@amarulasolutions.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Elena Reshetova <elena.reshetova@intel.com>
Cc: Jann Horn <jannh@google.com>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: KJ Tsanaktsidis <ktsanaktsidis@zendesk.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
task->saved_sigmask and ->restore_sigmask are only used in the ret-from-
syscall paths. This means that set_user_sigmask() can save ->blocked in
->saved_sigmask and do set_restore_sigmask() to indicate that ->blocked
was modified.
This way the callers do not need 2 sigset_t's passed to set/restore and
restore_user_sigmask() renamed to restore_saved_sigmask_unless() turns
into the trivial helper which just calls restore_saved_sigmask().
Link: http://lkml.kernel.org/r/20190606113206.GA9464@redhat.com
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Eric Wong <e@80x24.org>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: Eric W. Biederman <ebiederm@xmission.com>
Cc: David Laight <David.Laight@aculab.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
PTRACE_GET_SYSCALL_INFO is a generic ptrace API that lets ptracer obtain
details of the syscall the tracee is blocked in.
There are two reasons for a special syscall-related ptrace request.
Firstly, with the current ptrace API there are cases when ptracer cannot
retrieve necessary information about syscalls. Some examples include:
* The notorious int-0x80-from-64-bit-task issue. See [1] for details.
In short, if a 64-bit task performs a syscall through int 0x80, its
tracer has no reliable means to find out that the syscall was, in
fact, a compat syscall, and misidentifies it.
* Syscall-enter-stop and syscall-exit-stop look the same for the
tracer. Common practice is to keep track of the sequence of
ptrace-stops in order not to mix the two syscall-stops up. But it is
not as simple as it looks; for example, strace had a (just recently
fixed) long-standing bug where attaching strace to a tracee that is
performing the execve system call led to the tracer identifying the
following syscall-exit-stop as syscall-enter-stop, which messed up
all the state tracking.
* Since the introduction of commit 84d77d3f06 ("ptrace: Don't allow
accessing an undumpable mm"), both PTRACE_PEEKDATA and
process_vm_readv become unavailable when the process dumpable flag is
cleared. On such architectures as ia64 this results in all syscall
arguments being unavailable for the tracer.
Secondly, ptracers also have to support a lot of arch-specific code for
obtaining information about the tracee. For some architectures, this
requires a ptrace(PTRACE_PEEKUSER, ...) invocation for every syscall
argument and return value.
ptrace(2) man page:
long ptrace(enum __ptrace_request request, pid_t pid,
void *addr, void *data);
...
PTRACE_GET_SYSCALL_INFO
Retrieve information about the syscall that caused the stop.
The information is placed into the buffer pointed by "data"
argument, which should be a pointer to a buffer of type
"struct ptrace_syscall_info".
The "addr" argument contains the size of the buffer pointed to
by "data" argument (i.e., sizeof(struct ptrace_syscall_info)).
The return value contains the number of bytes available
to be written by the kernel.
If the size of data to be written by the kernel exceeds the size
specified by "addr" argument, the output is truncated.
[ldv@altlinux.org: selftests/seccomp/seccomp_bpf: update for PTRACE_GET_SYSCALL_INFO]
Link: http://lkml.kernel.org/r/20190708182904.GA12332@altlinux.org
Link: http://lkml.kernel.org/r/20190510152842.GF28558@altlinux.org
Signed-off-by: Elvira Khabirova <lineprinter@altlinux.org>
Co-developed-by: Dmitry V. Levin <ldv@altlinux.org>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Andy Lutomirski <luto@kernel.org>
Cc: Eugene Syromyatnikov <esyr@redhat.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greentime Hu <greentime@andestech.com>
Cc: Helge Deller <deller@gmx.de> [parisc]
Cc: James E.J. Bottomley <jejb@parisc-linux.org>
Cc: James Hogan <jhogan@kernel.org>
Cc: kbuild test robot <lkp@intel.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Burton <paul.burton@mips.com>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Richard Kuo <rkuo@codeaurora.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Vincent Chen <deanbo422@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
If a device doesn't support DMA to a physical address that includes the
encryption bit (currently bit 47, so 48-bit DMA), then the DMA must
occur to unencrypted memory. SWIOTLB is used to satisfy that requirement
if an IOMMU is not active (enabled or configured in passthrough mode).
However, commit fafadcd165 ("swiotlb: don't dip into swiotlb pool for
coherent allocations") modified the coherent allocation support in
SWIOTLB to use the DMA direct coherent allocation support. When an IOMMU
is not active, this resulted in dma_alloc_coherent() failing for devices
that didn't support DMA addresses that included the encryption bit.
Addressing this requires changes to the force_dma_unencrypted() function
in kernel/dma/direct.c. Since the function is now non-trivial and
SME/SEV specific, update the DMA direct support to add an arch override
for the force_dma_unencrypted() function. The arch override is selected
when CONFIG_AMD_MEM_ENCRYPT is set. The arch override function resides in
the arch/x86/mm/mem_encrypt.c file and forces unencrypted DMA when either
SEV is active or SME is active and the device does not support DMA to
physical addresses that include the encryption bit.
Fixes: fafadcd165 ("swiotlb: don't dip into swiotlb pool for coherent allocations")
Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tom Lendacky <thomas.lendacky@amd.com>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
[hch: moved the force_dma_unencrypted declaration to dma-mapping.h,
fold the s390 fix from Halil Pasic]
Signed-off-by: Christoph Hellwig <hch@lst.de>
-----BEGIN PGP SIGNATURE-----
iQIzBAABCAAdFiEE+QmuaPwR3wnBdVwACF8+vY7k4RUFAl0tpocACgkQCF8+vY7k
4RWoxA//b/fmDXP3WPzrjjSmpyB9ml0/epKzPbT5S2j0lftqKBmet29k+PCjVrTx
Nq2QauehY9ug5h8UMVUCmzPr95F0tSIGRoqk1vrn7z0K3q6k1SHrtvqbY1Bgb2Uk
Qvh2YFU4fQLJg8WAbExCjxCdbdmBKQVGKTwCtM+tP5OMxwAFOmQrjGaUaKCKIIA2
7Wzrx8CpSji+bJ3uK/d36c+4M9oDly5eaxBhoboL3BI0y+GqwiSASGwTO7BxrPOg
0wq5IZHnqS8+bprT9xQdDOqf+UOY9U1cxE/+sqsHxblfUEx9gfLy/R+FLmJn+SS9
Z3yLy4SqVHQMpWBjEAGodohikF60PAuTdymSC11jqFaKCUxWrIZg5xO+0blMrxPF
7vYIexutCkaBMHBlNaNsHIqB7B/2FGGKoN7QW64hwvwJCGvF7OmJcV+R4bROGvh4
nFuis9/Nm66Fq7I3aw37ThyZ0aWZdaQ0QJTH9ksxU/ZCz2hhMNYu/rXggrDvkS4U
nr77ZT5Gd7nj4b110zf8+99uiGiinY6hTfzPAuTCLBhaxwrv4/xDHAhpwdEB5T4j
8gOkxV8c0XWtL7sKqhGJvs/RRe2za0Y9XH6fyxsYfWcfuLjEvug8ouXMad9gxFWH
DL3WnKJEMGLScei2wux4kGOwEbkR1bUf2cHJfh3GpCB/y8vgLOc=
=smxY
-----END PGP SIGNATURE-----
Merge tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media
Pull rst conversion of docs from Mauro Carvalho Chehab:
"As agreed with Jon, I'm sending this big series directly to you, c/c
him, as this series required a special care, in order to avoid
conflicts with other trees"
* tag 'docs/v5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (77 commits)
docs: kbuild: fix build with pdf and fix some minor issues
docs: block: fix pdf output
docs: arm: fix a breakage with pdf output
docs: don't use nested tables
docs: gpio: add sysfs interface to the admin-guide
docs: locking: add it to the main index
docs: add some directories to the main documentation index
docs: add SPDX tags to new index files
docs: add a memory-devices subdir to driver-api
docs: phy: place documentation under driver-api
docs: serial: move it to the driver-api
docs: driver-api: add remaining converted dirs to it
docs: driver-api: add xilinx driver API documentation
docs: driver-api: add a series of orphaned documents
docs: admin-guide: add a series of orphaned documents
docs: cgroup-v1: add it to the admin-guide book
docs: aoe: add it to the driver-api book
docs: add some documentation dirs to the driver-api book
docs: driver-model: move it to the driver-api book
docs: lp855x-driver.rst: add it to the driver-api book
...
trace_get_fields() is the only way to read tracepoint fields at
run time, as their fields are defined at compile-time with macros.
Make this function visible to all users and it will be used by
trace event injection code to calculate the size of a tracepoint
entry.
Link: http://lkml.kernel.org/r/20190525165802.25944-4-xiyou.wangcong@gmail.com
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
filter_assign_type() could detect dynamic string and static
string, but not string pointers. Teach filter_assign_type()
to detect string pointers, and this will be needed by trace
event injection code.
BTW, trace event hist uses FILTER_PTR_STRING too.
Link: http://lkml.kernel.org/r/20190525165802.25944-3-xiyou.wangcong@gmail.com
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
All callers of tracing_generic_entry_update() have to initialize
entry->type, so let's just simply move it inside.
Link: http://lkml.kernel.org/r/20190525165802.25944-2-xiyou.wangcong@gmail.com
Cc: Ingo Molnar <mingo@redhat.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Change registered check only by trace_kprobe and remove
TP_FLAG_REGISTERED from trace_probe, since this feature
is only used for trace_kprobe.
Link: http://lkml.kernel.org/r/155931588704.28323.4952266828256245833.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add trace_event_call access APIs for trace_probe.
Instead of accessing trace_probe.call directly, use those
accesses by trace_probe_event_call() method. This hides
the relationship of trace_event_call and trace_probe from
trace_kprobe and trace_uprobe.
Link: http://lkml.kernel.org/r/155931587711.28323.8335129014686133120.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add trace_probe_name() and trace_probe_group_name() functions
for accessing probe name and group name of trace_probe.
Link: http://lkml.kernel.org/r/155931586717.28323.8738615064952254761.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add trace_probe_test/set/clear_flag() functions for accessing
trace_probe.flag field.
This flags field should not be accessed directly.
Link: http://lkml.kernel.org/r/155931585683.28323.314290023236905988.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add trace_event_file access APIs for trace_probe data structure.
This simplifies enabling/disabling operations in uprobe and kprobe
events so that those don't touch deep inside the trace_probe.
This also removing a redundant synchronization when the
kprobe event is used from perf, since the perf itself uses
tracepoint_synchronize_unregister() after disabling (ftrace-
defined) event, thus we don't have to synchronize in that
path. Also we don't need to identify local trace_kprobe too
anymore.
Link: http://lkml.kernel.org/r/155931584587.28323.372301976283354629.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since trace_event_call is a field of trace_probe, these
operations should be done in trace_probe.c. trace_kprobe
and trace_uprobe use new functions to register/unregister
trace_event_call.
Link: http://lkml.kernel.org/r/155931583643.28323.14828411185591538876.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Add common trace_probe init and cleanup function in
trace_probe.c, and use it from trace_kprobe.c and trace_uprobe.c
Link: http://lkml.kernel.org/r/155931582664.28323.5934870189034740822.stgit@devnote2
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Since arm64 kernel initializes breakpoint trap vector in arch_initcall(),
initializing kprobe (and run smoke test) in postcore_initcall() causes
a kernel panic.
To fix this issue, move the kprobe initialization in subsys_initcall()
(which is called right afer the arch_initcall).
In-kernel kprobe users (ftrace and bpf) are using fs_initcall() which is
called after subsys_initcall(), so this shouldn't cause more problem.
Link: http://lkml.kernel.org/r/155956708268.12228.10363800793132214198.stgit@devnote2
Link: http://lkml.kernel.org/r/20190709153755.GB10123@lakrids.cambridge.arm.com
Reported-by: Anders Roxell <anders.roxell@linaro.org>
Fixes: b5f8b32c93 ("kprobes: Initialize kprobes at postcore_initcall")
Tested-by: Anders Roxell <anders.roxell@linaro.org>
Tested-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXSxgkQAKCRCRxhvAZXjc
opJ3AP9TWIWhEC0dzbNmzh0STj/Vyl5KYEpdMbi7HNeAmIEAfQD6A3HI4bVJbN08
jH44U7DLzHJyHefKlB8jHEKEVYJWqgo=
=74Bg
-----END PGP SIGNATURE-----
Merge tag 'for-linus-20190715' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd and clone3 fixes from Christian Brauner:
"This contains a bugfix for CLONE_PIDFD when used with the legacy clone
syscall, two fixes to ensure that syscall numbering and clone3
entrypoint implementations will stay consistent, and an update for the
maintainers file:
- The addition of clone3 broke CLONE_PIDFD for legacy clone on all
architectures that use do_fork() directly instead of calling the
clone syscall itself. (Fwiw, cleaning do_fork() up is on my todo.)
The reason this happened was that during conversion of _do_fork()
to use struct kernel_clone_args we missed that do_fork() is called
directly by various architectures. This is fixed by making sure
that the pidfd argument in struct kernel_clone_args is correctly
initialized with the parent_tidptr argument passed down from
do_fork(). Additionally, do_fork() missed a check to make
CLONE_PIDFD and CLONE_PARENT_SETTID mutually exclusive just a
clone() does. This is now fixed too.
- When clone3() was introduced we skipped architectures that require
special handling for fork-like syscalls. Their syscall tables did
not contain any mention of clone3().
To make sure that Arnd's work to make syscall numbers on all
architectures identical (minus alpha) was not for naught we are
placing a comment in all syscall tables that do not yet implement
clone3(). The comment makes it clear that 435 is reserved for
clone3 and should not be used.
- Also, this contains a patch to make the clone3() syscall definition
in asm-generic/unist.h conditional on __ARCH_WANT_SYS_CLONE3. This
lets us catch new architectures that implicitly make use of clone3
without setting __ARCH_WANT_SYS_CLONE3 which is a good indicator
that they did not check whether it needs special treatment or not.
- Finally, this contains a patch to add me as maintainer for pidfd
stuff so people can start blaming me (more)"
* tag 'for-linus-20190715' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
MAINTAINERS: add new entry for pidfd api
unistd: protect clone3 via __ARCH_WANT_SYS_CLONE3
arch: mark syscall number 435 reserved for clone3
clone: fix CLONE_PIDFD support
BTF verifier has a size resolution bug which in some circumstances leads to
invalid size resolution for, e.g., TYPEDEF modifier. This happens if we have
[1] PTR -> [2] TYPEDEF -> [3] ARRAY, in which case due to being in pointer
context ARRAY size won't be resolved (because for pointer it doesn't matter, so
it's a sink in pointer context), but it will be permanently remembered as zero
for TYPEDEF and TYPEDEF will be marked as RESOLVED. Eventually ARRAY size will
be resolved correctly, but TYPEDEF resolved_size won't be updated anymore.
This, subsequently, will lead to erroneous map creation failure, if that
TYPEDEF is specified as either key or value, as key_size/value_size won't
correspond to resolved size of TYPEDEF (kernel will believe it's zero).
Note, that if BTF was ordered as [1] ARRAY <- [2] TYPEDEF <- [3] PTR, this
won't be a problem, as by the time we get to TYPEDEF, ARRAY's size is already
calculated and stored.
This bug manifests itself in rejecting BTF-defined maps that use array
typedef as a value type:
typedef int array_t[16];
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(value, array_t); /* i.e., array_t *value; */
} test_map SEC(".maps");
The fix consists on not relying on modifier's resolved_size and instead using
modifier's resolved_id (type ID for "concrete" type to which modifier
eventually resolves) and doing size determination for that resolved type. This
allow to preserve existing "early DFS termination" logic for PTR or
STRUCT_OR_ARRAY contexts, but still do correct size determination for modifier
types.
Fixes: eb3f595dab ("bpf: btf: Validate type reference")
Cc: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The stuff under sysctl describes /sys interface from userspace
point of view. So, add it to the admin-guide and remove the
:orphan: from its index file.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Rename the /proc/sys/ documentation files to ReST, using the
README file as a template for an index.rst, adding the other
files there via TOC markup.
Despite being written on different times with different
styles, try to make them somewhat coherent with a similar
look and feel, ensuring that they'll look nice as both
raw text file and as via the html output produced by the
Sphinx build system.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Convert the locking documents to ReST and add them to the
kernel development book where it belongs.
Most of the stuff here is just to make Sphinx to properly
parse the text file, as they're already in good shape,
not requiring massive changes in order to be parsed.
The conversion is actually:
- add blank lines and identation in order to identify paragraphs;
- fix tables markups;
- add some lists markups;
- mark literal blocks;
- adjust title markups.
At its new index.rst, let's add a :orphan: while this is not linked to
the main index.rst file, in order to avoid build warnings.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Acked-by: Federico Vaga <federico.vaga@vaga.pv.it>
Improvements and bug fixes for the hmm interface in the kernel:
- Improve clarity, locking and APIs related to the 'hmm mirror' feature
merged last cycle. In linux-next we now see AMDGPU and nouveau to be
using this API.
- Remove old or transitional hmm APIs. These are hold overs from the past
with no users, or APIs that existed only to manage cross tree conflicts.
There are still a few more of these cleanups that didn't make the merge
window cut off.
- Improve some core mm APIs:
* export alloc_pages_vma() for driver use
* refactor into devm_request_free_mem_region() to manage
DEVICE_PRIVATE resource reservations
* refactor duplicative driver code into the core dev_pagemap
struct
- Remove hmm wrappers of improved core mm APIs, instead have drivers use
the simplified API directly
- Remove DEVICE_PUBLIC
- Simplify the kconfig flow for the hmm users and core code
-----BEGIN PGP SIGNATURE-----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=wKvp
-----END PGP SIGNATURE-----
Merge tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma
Pull HMM updates from Jason Gunthorpe:
"Improvements and bug fixes for the hmm interface in the kernel:
- Improve clarity, locking and APIs related to the 'hmm mirror'
feature merged last cycle. In linux-next we now see AMDGPU and
nouveau to be using this API.
- Remove old or transitional hmm APIs. These are hold overs from the
past with no users, or APIs that existed only to manage cross tree
conflicts. There are still a few more of these cleanups that didn't
make the merge window cut off.
- Improve some core mm APIs:
- export alloc_pages_vma() for driver use
- refactor into devm_request_free_mem_region() to manage
DEVICE_PRIVATE resource reservations
- refactor duplicative driver code into the core dev_pagemap
struct
- Remove hmm wrappers of improved core mm APIs, instead have drivers
use the simplified API directly
- Remove DEVICE_PUBLIC
- Simplify the kconfig flow for the hmm users and core code"
* tag 'for-linus-hmm' of git://git.kernel.org/pub/scm/linux/kernel/git/rdma/rdma: (42 commits)
mm: don't select MIGRATE_VMA_HELPER from HMM_MIRROR
mm: remove the HMM config option
mm: sort out the DEVICE_PRIVATE Kconfig mess
mm: simplify ZONE_DEVICE page private data
mm: remove hmm_devmem_add
mm: remove hmm_vma_alloc_locked_page
nouveau: use devm_memremap_pages directly
nouveau: use alloc_page_vma directly
PCI/P2PDMA: use the dev_pagemap internal refcount
device-dax: use the dev_pagemap internal refcount
memremap: provide an optional internal refcount in struct dev_pagemap
memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag
memremap: remove the data field in struct dev_pagemap
memremap: add a migrate_to_ram method to struct dev_pagemap_ops
memremap: lift the devmap_enable manipulation into devm_memremap_pages
memremap: pass a struct dev_pagemap to ->kill and ->cleanup
memremap: move dev_pagemap callbacks into a separate structure
memremap: validate the pagemap type passed to devm_memremap_pages
mm: factor out a devm_request_free_mem_region helper
mm: export alloc_pages_vma
...
Pull perf fixes from Ingo Molnar:
"A number of PMU driver corner case fixes, a race fix, an event
grouping fix, plus a bunch of tooling fixes/updates"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (30 commits)
perf/x86/intel: Fix spurious NMI on fixed counter
perf/core: Fix exclusive events' grouping
perf/x86/amd/uncore: Set the thread mask for F17h L3 PMCs
perf/x86/amd/uncore: Do not set 'ThreadMask' and 'SliceMask' for non-L3 PMCs
perf/core: Fix race between close() and fork()
perf intel-pt: Fix potential NULL pointer dereference found by the smatch tool
perf intel-bts: Fix potential NULL pointer dereference found by the smatch tool
perf script: Assume native_arch for pipe mode
perf scripts python: export-to-sqlite.py: Fix DROP VIEW power_events_view
perf scripts python: export-to-postgresql.py: Fix DROP VIEW power_events_view
perf hists browser: Fix potential NULL pointer dereference found by the smatch tool
perf cs-etm: Fix potential NULL pointer dereference found by the smatch tool
perf parse-events: Remove unused variable: error
perf parse-events: Remove unused variable 'i'
perf metricgroup: Add missing list_del_init() when flushing egroups list
perf tools: Use list_del_init() more thorougly
perf tools: Use zfree() where applicable
tools lib: Adopt zalloc()/zfree() from tools/perf
perf tools: Move get_current_dir_name() cond prototype out of util.h
perf namespaces: Move the conditional setns() prototype to namespaces.h
...
Pull locking fix from Ingo Molnar:
"A single fix for a locking statistics bug"
* 'locking-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/lockdep: Fix lock used or unused stats error
The introduction of clone3 syscall accidentally broke CLONE_PIDFD
support in traditional clone syscall on compat x86 and those
architectures that use do_fork to implement clone syscall.
This bug was found by strace test suite.
Link: https://strace.io/logs/strace/2019-07-12
Fixes: 7f192e3cd3 ("fork: add clone3")
Bisected-and-tested-by: Anatoly Pugachev <matorola@gmail.com>
Signed-off-by: Dmitry V. Levin <ldv@altlinux.org>
Link: https://lore.kernel.org/r/20190714162047.GB10389@altlinux.org
Signed-off-by: Christian Brauner <christian@brauner.io>
Pull scheduler fix from Ingo Molnar:
"Fix a sched statistics related bug that would trigger a kernel warning
on certain configs"
* 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/core: Fix preempt warning in ttwu
The stats variable nr_unused_locks is incremented every time a new lock
class is register and decremented when the lock is first used in
__lock_acquire(). And after all, it is shown and checked in lockdep_stats.
However, under configurations that either CONFIG_TRACE_IRQFLAGS or
CONFIG_PROVE_LOCKING is not defined:
The commit:
0918065151 ("locking/lockdep: Consolidate lock usage bit initialization")
missed marking the LOCK_USED flag at IRQ usage initialization because
as mark_usage() is not called. And the commit:
886532aee3 ("locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING")
further made mark_lock() not defined such that the LOCK_USED cannot be
marked at all when the lock is first acquired.
As a result, we fix this by not showing and checking the stats under such
configurations for lockdep_stats.
Reported-by: Qian Cai <cai@lca.pw>
Signed-off-by: Yuyang Du <duyuyang@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: arnd@arndb.de
Cc: frederic@kernel.org
Link: https://lkml.kernel.org/r/20190709101522.9117-1-duyuyang@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
John reported a DEBUG_PREEMPT warning caused by commit:
aacedf26fb ("sched/core: Optimize try_to_wake_up() for local wakeups")
I overlooked that ttwu_stat() requires preemption disabled.
Reported-by: John Stultz <john.stultz@linaro.org>
Tested-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Fixes: aacedf26fb ("sched/core: Optimize try_to_wake_up() for local wakeups")
Link: https://lkml.kernel.org/r/20190710105736.GK3402@hirez.programming.kicks-ass.net
Signed-off-by: Ingo Molnar <mingo@kernel.org>
So far, we tried to disallow grouping exclusive events for the fear of
complications they would cause with moving between contexts. Specifically,
moving a software group to a hardware context would violate the exclusivity
rules if both groups contain matching exclusive events.
This attempt was, however, unsuccessful: the check that we have in the
perf_event_open() syscall is both wrong (looks at wrong PMU) and
insufficient (group leader may still be exclusive), as can be illustrated
by running:
$ perf record -e '{intel_pt//,cycles}' uname
$ perf record -e '{cycles,intel_pt//}' uname
ultimately successfully.
Furthermore, we are completely free to trigger the exclusivity violation
by:
perf -e '{cycles,intel_pt//}' -e '{intel_pt//,instructions}'
even though the helpful perf record will not allow that, the ABI will.
The warning later in the perf_event_open() path will also not trigger, because
it's also wrong.
Fix all this by validating the original group before moving, getting rid
of broken safeguards and placing a useful one to perf_install_in_context().
Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: mathieu.poirier@linaro.org
Cc: will.deacon@arm.com
Fixes: bed5b25ad9 ("perf: Add a pmu capability for "exclusive" events")
Link: https://lkml.kernel.org/r/20190701110755.24646-1-alexander.shishkin@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Syzcaller reported the following Use-after-Free bug:
close() clone()
copy_process()
perf_event_init_task()
perf_event_init_context()
mutex_lock(parent_ctx->mutex)
inherit_task_group()
inherit_group()
inherit_event()
mutex_lock(event->child_mutex)
// expose event on child list
list_add_tail()
mutex_unlock(event->child_mutex)
mutex_unlock(parent_ctx->mutex)
...
goto bad_fork_*
bad_fork_cleanup_perf:
perf_event_free_task()
perf_release()
perf_event_release_kernel()
list_for_each_entry()
mutex_lock(ctx->mutex)
mutex_lock(event->child_mutex)
// event is from the failing inherit
// on the other CPU
perf_remove_from_context()
list_move()
mutex_unlock(event->child_mutex)
mutex_unlock(ctx->mutex)
mutex_lock(ctx->mutex)
list_for_each_entry_safe()
// event already stolen
mutex_unlock(ctx->mutex)
delayed_free_task()
free_task()
list_for_each_entry_safe()
list_del()
free_event()
_free_event()
// and so event->hw.target
// is the already freed failed clone()
if (event->hw.target)
put_task_struct(event->hw.target)
// WHOOPSIE, already quite dead
Which puts the lie to the the comment on perf_event_free_task():
'unexposed, unused context' not so much.
Which is a 'fun' confluence of fail; copy_process() doing an
unconditional free_task() and not respecting refcounts, and perf having
creative locking. In particular:
82d94856fa ("perf/core: Fix lock inversion between perf,trace,cpuhp")
seems to have overlooked this 'fun' parade.
Solve it by using the fact that detached events still have a reference
count on their (previous) context. With this perf_event_free_task()
can detect when events have escaped and wait for their destruction.
Debugged-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reported-by: syzbot+a24c397a29ad22d86c98@syzkaller.appspotmail.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: 82d94856fa ("perf/core: Fix lock inversion between perf,trace,cpuhp")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
- remove headers_{install,check}_all targets
- remove unreasonable 'depends on !UML' from CONFIG_SAMPLES
- re-implement 'make headers_install' more cleanly
- add new header-test-y syntax to compile-test headers
- compile-test exported headers to ensure they are compilable in
user-space
- compile-test headers under include/ to ensure they are self-contained
- remove -Waggregate-return, -Wno-uninitialized, -Wno-unused-value flags
- add -Werror=unknown-warning-option for Clang
- add 128-bit built-in types support to genksyms
- fix missed rebuild of modules.builtin
- propagate 'No space left on device' error in fixdep to Make
- allow Clang to use its integrated assembler
- improve some coccinelle scripts
- add a new flag KBUILD_ABS_SRCTREE to request Kbuild to use absolute
path for $(srctree).
- do not ignore errors when compression utility is missing
- misc cleanups
-----BEGIN PGP SIGNATURE-----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=E2Rz
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- remove headers_{install,check}_all targets
- remove unreasonable 'depends on !UML' from CONFIG_SAMPLES
- re-implement 'make headers_install' more cleanly
- add new header-test-y syntax to compile-test headers
- compile-test exported headers to ensure they are compilable in
user-space
- compile-test headers under include/ to ensure they are self-contained
- remove -Waggregate-return, -Wno-uninitialized, -Wno-unused-value
flags
- add -Werror=unknown-warning-option for Clang
- add 128-bit built-in types support to genksyms
- fix missed rebuild of modules.builtin
- propagate 'No space left on device' error in fixdep to Make
- allow Clang to use its integrated assembler
- improve some coccinelle scripts
- add a new flag KBUILD_ABS_SRCTREE to request Kbuild to use absolute
path for $(srctree).
- do not ignore errors when compression utility is missing
- misc cleanups
* tag 'kbuild-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (49 commits)
kbuild: use -- separater intead of $(filter-out ...) for cc-cross-prefix
kbuild: Inform user to pass ARCH= for make mrproper
kbuild: fix compression errors getting ignored
kbuild: add a flag to force absolute path for srctree
kbuild: replace KBUILD_SRCTREE with boolean building_out_of_srctree
kbuild: remove src and obj from the top Makefile
scripts/tags.sh: remove unused environment variables from comments
scripts/tags.sh: drop SUBARCH support for ARM
kbuild: compile-test kernel headers to ensure they are self-contained
kheaders: include only headers into kheaders_data.tar.xz
kheaders: remove meaningless -R option of 'ls'
kbuild: support header-test-pattern-y
kbuild: do not create wrappers for header-test-y
kbuild: compile-test exported headers to ensure they are self-contained
init/Kconfig: add CONFIG_CC_CAN_LINK
kallsyms: exclude kasan local symbols on s390
kbuild: add more hints about SUBDIRS replacement
coccinelle: api/stream_open: treat all wait_.*() calls as blocking
coccinelle: put_device: Add a cast to an expression for an assignment
coccinelle: put_device: Adjust a message construction
...
- move the USB special case that bounced DMA through a device
bar into the USB code instead of handling it in the common
DMA code (Laurentiu Tudor and Fredrik Noring)
- don't dip into the global CMA pool for single page allocations
(Nicolin Chen)
- fix a crash when allocating memory for the atomic pool failed
during boot (Florian Fainelli)
- move support for MIPS-style uncached segments to the common
code and use that for MIPS and nios2 (me)
- make support for DMA_ATTR_NON_CONSISTENT and
DMA_ATTR_NO_KERNEL_MAPPING generic (me)
- convert nds32 to the generic remapping allocator (me)
-----BEGIN PGP SIGNATURE-----
iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAl0nPqgLHGhjaEBsc3Qu
ZGUACgkQD55TZVIEUYNj2hAAxIv2O3wv6V5xhzWwOVo8e/xW1ZLlGAF0/z92u0do
32Tm8jkdAGjZDnyxam7qisMSIjCNykpauQzVVxyUNBRSsn1V5t7KSaH3/OXCOVcr
x2VWBirxGO2BbRseaCBjIcA/2qna+VIDGFcNXCtf6rM00YUK6qaJzkMwBKQAeYcM
uJMJkaf8qaW4hygLJP8axXiGFdIJyFNLAlJ+ok6kYsJHHJNceOp0bo3CDa2mJBK9
IhraK2zVkyE5EQkQM5cE/Kw1ppPelUKUkHwjgM4wpz2b18WbLu11nKP0hmUcvKRQ
heY8xWiKxN0QTgS03ou7EVylyrSAE4dIKgzuA4VO32QCGsWypcAg4iU6s5TX6p9g
tZEW2ckE6wbmRdQPyKoDpZg299/eQjRHc4MAA1yinT8tFMokw2tk8Fq1FWyltwL1
8EiP5oNs2qUNvNgqUresl6/f6YOacFi1Q6IhgBVj6d6lyhMhlsHfW4w1XA1siv/I
6l4qJbLohYab6hY7i+mBOd8iG/KrAlr4P6admnv2jDchswbb5t2j+ABE9xv++PFi
u1HFqMlxqdWQaXGca2UeCUxUjkwO9N+kHpP+VRz+6D2b64dtCWSu8CN23sYXm2tO
ubWIlrQQZPhhMkoFg7XqKSTacd+ut+SXN9Nxsyv548ETV0l1xbiLRHIbhyoIESD5
RAI=
=01Fr
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- move the USB special case that bounced DMA through a device bar into
the USB code instead of handling it in the common DMA code (Laurentiu
Tudor and Fredrik Noring)
- don't dip into the global CMA pool for single page allocations
(Nicolin Chen)
- fix a crash when allocating memory for the atomic pool failed during
boot (Florian Fainelli)
- move support for MIPS-style uncached segments to the common code and
use that for MIPS and nios2 (me)
- make support for DMA_ATTR_NON_CONSISTENT and
DMA_ATTR_NO_KERNEL_MAPPING generic (me)
- convert nds32 to the generic remapping allocator (me)
* tag 'dma-mapping-5.3' of git://git.infradead.org/users/hch/dma-mapping: (29 commits)
dma-mapping: mark dma_alloc_need_uncached as __always_inline
MIPS: only select ARCH_HAS_UNCACHED_SEGMENT for non-coherent platforms
usb: host: Fix excessive alignment restriction for local memory allocations
lib/genalloc.c: Add algorithm, align and zeroed family of DMA allocators
nios2: use the generic uncached segment support in dma-direct
nds32: use the generic remapping allocator for coherent DMA allocations
arc: use the generic remapping allocator for coherent DMA allocations
dma-direct: handle DMA_ATTR_NO_KERNEL_MAPPING in common code
dma-direct: handle DMA_ATTR_NON_CONSISTENT in common code
dma-mapping: add a dma_alloc_need_uncached helper
openrisc: remove the partial DMA_ATTR_NON_CONSISTENT support
arc: remove the partial DMA_ATTR_NON_CONSISTENT support
arm-nommu: remove the partial DMA_ATTR_NON_CONSISTENT support
ARM: dma-mapping: allow larger DMA mask than supported
dma-mapping: truncate dma masks to what dma_addr_t can hold
iommu/dma: Apply dma_{alloc,free}_contiguous functions
dma-remap: Avoid de-referencing NULL atomic_pool
MIPS: use the generic uncached segment support in dma-direct
dma-direct: provide generic support for uncached kernel segments
au1100fb: fix DMA API abuse
...
Here is the "big" driver core and debugfs changes for 5.3-rc1
It's a lot of different patches, all across the tree due to some api
changes and lots of debugfs cleanups. Because of this, there is going
to be some merge issues with your tree at the moment, I'll follow up
with the expected resolutions to make it easier for you.
Other than the debugfs cleanups, in this set of changes we have:
- bus iteration function cleanups (will cause build warnings
with s390 and coresight drivers in your tree)
- scripts/get_abi.pl tool to display and parse Documentation/ABI
entries in a simple way
- cleanups to Documenatation/ABI/ entries to make them parse
easier due to typos and other minor things
- default_attrs use for some ktype users
- driver model documentation file conversions to .rst
- compressed firmware file loading
- deferred probe fixes
All of these have been in linux-next for a while, with a bunch of merge
issues that Stephen has been patient with me for. Other than the merge
issues, functionality is working properly in linux-next :)
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXSgpnQ8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ykcwgCfS30OR4JmwZydWGJ7zK/cHqk+KjsAnjOxjC1K
LpRyb3zX29oChFaZkc5a
=XrEZ
-----END PGP SIGNATURE-----
Merge tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core
Pull driver core and debugfs updates from Greg KH:
"Here is the "big" driver core and debugfs changes for 5.3-rc1
It's a lot of different patches, all across the tree due to some api
changes and lots of debugfs cleanups.
Other than the debugfs cleanups, in this set of changes we have:
- bus iteration function cleanups
- scripts/get_abi.pl tool to display and parse Documentation/ABI
entries in a simple way
- cleanups to Documenatation/ABI/ entries to make them parse easier
due to typos and other minor things
- default_attrs use for some ktype users
- driver model documentation file conversions to .rst
- compressed firmware file loading
- deferred probe fixes
All of these have been in linux-next for a while, with a bunch of
merge issues that Stephen has been patient with me for"
* tag 'driver-core-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (102 commits)
debugfs: make error message a bit more verbose
orangefs: fix build warning from debugfs cleanup patch
ubifs: fix build warning after debugfs cleanup patch
driver: core: Allow subsystems to continue deferring probe
drivers: base: cacheinfo: Ensure cpu hotplug work is done before Intel RDT
arch_topology: Remove error messages on out-of-memory conditions
lib: notifier-error-inject: no need to check return value of debugfs_create functions
swiotlb: no need to check return value of debugfs_create functions
ceph: no need to check return value of debugfs_create functions
sunrpc: no need to check return value of debugfs_create functions
ubifs: no need to check return value of debugfs_create functions
orangefs: no need to check return value of debugfs_create functions
nfsd: no need to check return value of debugfs_create functions
lib: 842: no need to check return value of debugfs_create functions
debugfs: provide pr_fmt() macro
debugfs: log errors when something goes wrong
drivers: s390/cio: Fix compilation warning about const qualifiers
drivers: Add generic helper to match by of_node
driver_find_device: Unify the match function with class_find_device()
bus_find_device: Unify the match callback with class_find_device
...
Merge updates from Andrew Morton:
"Am experimenting with splitting MM up into identifiable subsystems
perhaps with a view to gitifying it in complex ways. Also with more
verbose "incoming" emails.
Most of MM is here and a few other trees.
Subsystems affected by this patch series:
- hotfixes
- iommu
- scripts
- arch/sh
- ocfs2
- mm:slab-generic
- mm:slub
- mm:kmemleak
- mm:kasan
- mm:cleanups
- mm:debug
- mm:pagecache
- mm:swap
- mm:memcg
- mm:gup
- mm:pagemap
- mm:infrastructure
- mm:vmalloc
- mm:initialization
- mm:pagealloc
- mm:vmscan
- mm:tools
- mm:proc
- mm:ras
- mm:oom-kill
hotfixes:
mm: vmscan: scan anonymous pages on file refaults
mm/nvdimm: add is_ioremap_addr and use that to check ioremap address
mm/memcontrol: fix wrong statistics in memory.stat
mm/z3fold.c: lock z3fold page before __SetPageMovable()
nilfs2: do not use unexported cpu_to_le32()/le32_to_cpu() in uapi header
MAINTAINERS: nilfs2: update email address
iommu:
include/linux/dmar.h: replace single-char identifiers in macros
scripts:
scripts/decode_stacktrace: match basepath using shell prefix operator, not regex
scripts/decode_stacktrace: look for modules with .ko.debug extension
scripts/spelling.txt: drop "sepc" from the misspelling list
scripts/spelling.txt: add spelling fix for prohibited
scripts/decode_stacktrace: Accept dash/underscore in modules
scripts/spelling.txt: add more spellings to spelling.txt
arch/sh:
arch/sh/configs/sdk7786_defconfig: remove CONFIG_LOGFS
sh: config: remove left-over BACKLIGHT_LCD_SUPPORT
sh: prevent warnings when using iounmap
ocfs2:
fs: ocfs: fix spelling mistake "hearbeating" -> "heartbeat"
ocfs2/dlm: use struct_size() helper
ocfs2: add last unlock times in locking_state
ocfs2: add locking filter debugfs file
ocfs2: add first lock wait time in locking_state
ocfs: no need to check return value of debugfs_create functions
fs/ocfs2/dlmglue.c: unneeded variable: "status"
ocfs2: use kmemdup rather than duplicating its implementation
mm:slab-generic:
Patch series "mm/slab: Improved sanity checking":
mm/slab: validate cache membership under freelist hardening
mm/slab: sanity-check page type when looking up cache
lkdtm/heap: add tests for freelist hardening
mm:slub:
mm/slub.c: avoid double string traverse in kmem_cache_flags()
slub: don't panic for memcg kmem cache creation failure
mm:kmemleak:
mm/kmemleak.c: fix check for softirq context
mm/kmemleak.c: change error at _write when kmemleak is disabled
docs: kmemleak: add more documentation details
mm:kasan:
mm/kasan: print frame description for stack bugs
Patch series "Bitops instrumentation for KASAN", v5:
lib/test_kasan: add bitops tests
x86: use static_cpu_has in uaccess region to avoid instrumentation
asm-generic, x86: add bitops instrumentation for KASAN
Patch series "mm/kasan: Add object validation in ksize()", v3:
mm/kasan: introduce __kasan_check_{read,write}
mm/kasan: change kasan_check_{read,write} to return boolean
lib/test_kasan: Add test for double-kzfree detection
mm/slab: refactor common ksize KASAN logic into slab_common.c
mm/kasan: add object validation in ksize()
mm:cleanups:
include/linux/pfn_t.h: remove pfn_t_to_virt()
Patch series "remove ARCH_SELECT_MEMORY_MODEL where it has no effect":
arm: remove ARCH_SELECT_MEMORY_MODEL
s390: remove ARCH_SELECT_MEMORY_MODEL
sparc: remove ARCH_SELECT_MEMORY_MODEL
mm/gup.c: make follow_page_mask() static
mm/memory.c: trivial clean up in insert_page()
mm: make !CONFIG_HUGE_PAGE wrappers into static inlines
include/linux/mm_types.h: ifdef struct vm_area_struct::swap_readahead_info
mm: remove the account_page_dirtied export
mm/page_isolation.c: change the prototype of undo_isolate_page_range()
include/linux/vmpressure.h: use spinlock_t instead of struct spinlock
mm: remove the exporting of totalram_pages
include/linux/pagemap.h: document trylock_page() return value
mm:debug:
mm/failslab.c: by default, do not fail allocations with direct reclaim only
Patch series "debug_pagealloc improvements":
mm, debug_pagelloc: use static keys to enable debugging
mm, page_alloc: more extensive free page checking with debug_pagealloc
mm, debug_pagealloc: use a page type instead of page_ext flag
mm:pagecache:
Patch series "fix filler_t callback type mismatches", v2:
mm/filemap.c: fix an overly long line in read_cache_page
mm/filemap: don't cast ->readpage to filler_t for do_read_cache_page
jffs2: pass the correct prototype to read_cache_page
9p: pass the correct prototype to read_cache_page
mm/filemap.c: correct the comment about VM_FAULT_RETRY
mm:swap:
mm, swap: fix race between swapoff and some swap operations
mm/swap_state.c: simplify total_swapcache_pages() with get_swap_device()
mm, swap: use rbtree for swap_extent
mm/mincore.c: fix race between swapoff and mincore
mm:memcg:
memcg, oom: no oom-kill for __GFP_RETRY_MAYFAIL
memcg, fsnotify: no oom-kill for remote memcg charging
mm, memcg: introduce memory.events.local
mm: memcontrol: dump memory.stat during cgroup OOM
Patch series "mm: reparent slab memory on cgroup removal", v7:
mm: memcg/slab: postpone kmem_cache memcg pointer initialization to memcg_link_cache()
mm: memcg/slab: rename slab delayed deactivation functions and fields
mm: memcg/slab: generalize postponed non-root kmem_cache deactivation
mm: memcg/slab: introduce __memcg_kmem_uncharge_memcg()
mm: memcg/slab: unify SLAB and SLUB page accounting
mm: memcg/slab: don't check the dying flag on kmem_cache creation
mm: memcg/slab: synchronize access to kmem_cache dying flag using a spinlock
mm: memcg/slab: rework non-root kmem_cache lifecycle management
mm: memcg/slab: stop setting page->mem_cgroup pointer for slab pages
mm: memcg/slab: reparent memcg kmem_caches on cgroup removal
mm, memcg: add a memcg_slabinfo debugfs file
mm:gup:
Patch series "switch the remaining architectures to use generic GUP", v4:
mm: use untagged_addr() for get_user_pages_fast addresses
mm: simplify gup_fast_permitted
mm: lift the x86_32 PAE version of gup_get_pte to common code
MIPS: use the generic get_user_pages_fast code
sh: add the missing pud_page definition
sh: use the generic get_user_pages_fast code
sparc64: add the missing pgd_page definition
sparc64: define untagged_addr()
sparc64: use the generic get_user_pages_fast code
mm: rename CONFIG_HAVE_GENERIC_GUP to CONFIG_HAVE_FAST_GUP
mm: reorder code blocks in gup.c
mm: consolidate the get_user_pages* implementations
mm: validate get_user_pages_fast flags
mm: move the powerpc hugepd code to mm/gup.c
mm: switch gup_hugepte to use try_get_compound_head
mm: mark the page referenced in gup_hugepte
mm/gup: speed up check_and_migrate_cma_pages() on huge page
mm/gup.c: remove some BUG_ONs from get_gate_page()
mm/gup.c: mark undo_dev_pagemap as __maybe_unused
mm:pagemap:
asm-generic, x86: introduce generic pte_{alloc,free}_one[_kernel]
alpha: switch to generic version of pte allocation
arm: switch to generic version of pte allocation
arm64: switch to generic version of pte allocation
csky: switch to generic version of pte allocation
m68k: sun3: switch to generic version of pte allocation
mips: switch to generic version of pte allocation
nds32: switch to generic version of pte allocation
nios2: switch to generic version of pte allocation
parisc: switch to generic version of pte allocation
riscv: switch to generic version of pte allocation
um: switch to generic version of pte allocation
unicore32: switch to generic version of pte allocation
mm/pgtable: drop pgtable_t variable from pte_fn_t functions
mm/memory.c: fail when offset == num in first check of __vm_map_pages()
mm:infrastructure:
mm/mmu_notifier: use hlist_add_head_rcu()
mm:vmalloc:
Patch series "Some cleanups for the KVA/vmalloc", v5:
mm/vmalloc.c: remove "node" argument
mm/vmalloc.c: preload a CPU with one object for split purpose
mm/vmalloc.c: get rid of one single unlink_va() when merge
mm/vmalloc.c: switch to WARN_ON() and move it under unlink_va()
mm/vmalloc.c: spelling> s/informaion/information/
mm:initialization:
mm/large system hash: use vmalloc for size > MAX_ORDER when !hashdist
mm/large system hash: clear hashdist when only one node with memory is booted
mm:pagealloc:
arm64: move jump_label_init() before parse_early_param()
Patch series "add init_on_alloc/init_on_free boot options", v10:
mm: security: introduce init_on_alloc=1 and init_on_free=1 boot options
mm: init: report memory auto-initialization features at boot time
mm:vmscan:
mm: vmscan: remove double slab pressure by inc'ing sc->nr_scanned
mm: vmscan: correct some vmscan counters for THP swapout
mm:tools:
tools/vm/slabinfo: order command line options
tools/vm/slabinfo: add partial slab listing to -X
tools/vm/slabinfo: add option to sort by partial slabs
tools/vm/slabinfo: add sorting info to help menu
mm:proc:
proc: use down_read_killable mmap_sem for /proc/pid/maps
proc: use down_read_killable mmap_sem for /proc/pid/smaps_rollup
proc: use down_read_killable mmap_sem for /proc/pid/pagemap
proc: use down_read_killable mmap_sem for /proc/pid/clear_refs
proc: use down_read_killable mmap_sem for /proc/pid/map_files
mm: use down_read_killable for locking mmap_sem in access_remote_vm
mm: smaps: split PSS into components
mm: vmalloc: show number of vmalloc pages in /proc/meminfo
mm:ras:
mm/memory-failure.c: clarify error message
mm:oom-kill:
mm: memcontrol: use CSS_TASK_ITER_PROCS at mem_cgroup_scan_tasks()
mm, oom: refactor dump_tasks for memcg OOMs
mm, oom: remove redundant task_in_mem_cgroup() check
oom: decouple mems_allowed from oom_unkillable_task
mm/oom_kill.c: remove redundant OOM score normalization in select_bad_process()"
* akpm: (147 commits)
mm/oom_kill.c: remove redundant OOM score normalization in select_bad_process()
oom: decouple mems_allowed from oom_unkillable_task
mm, oom: remove redundant task_in_mem_cgroup() check
mm, oom: refactor dump_tasks for memcg OOMs
mm: memcontrol: use CSS_TASK_ITER_PROCS at mem_cgroup_scan_tasks()
mm/memory-failure.c: clarify error message
mm: vmalloc: show number of vmalloc pages in /proc/meminfo
mm: smaps: split PSS into components
mm: use down_read_killable for locking mmap_sem in access_remote_vm
proc: use down_read_killable mmap_sem for /proc/pid/map_files
proc: use down_read_killable mmap_sem for /proc/pid/clear_refs
proc: use down_read_killable mmap_sem for /proc/pid/pagemap
proc: use down_read_killable mmap_sem for /proc/pid/smaps_rollup
proc: use down_read_killable mmap_sem for /proc/pid/maps
tools/vm/slabinfo: add sorting info to help menu
tools/vm/slabinfo: add option to sort by partial slabs
tools/vm/slabinfo: add partial slab listing to -X
tools/vm/slabinfo: order command line options
mm: vmscan: correct some vmscan counters for THP swapout
mm: vmscan: remove double slab pressure by inc'ing sc->nr_scanned
...
Architectures like powerpc use different address range to map ioremap
and vmalloc range. The memunmap() check used by the nvdimm layer was
wrongly using is_vmalloc_addr() to check for ioremap range which fails
for ppc64. This result in ppc64 not freeing the ioremap mapping. The
side effect of this is an unbind failure during module unload with
papr_scm nvdimm driver
Link: http://lkml.kernel.org/r/20190701134038.14165-1-aneesh.kumar@linux.ibm.com
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Fixes: b5beae5e22 ("powerpc/pseries: Add driver for PAPR SCM regions")
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In preparation to enabling -Wimplicit-fallthrough, this patch silences
the following warning:
kernel/bpf/verifier.c: In function ‘check_return_code’:
kernel/bpf/verifier.c:6106:6: warning: this statement may fall through [-Wimplicit-fallthrough=]
if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG ||
^
kernel/bpf/verifier.c:6109:2: note: here
case BPF_PROG_TYPE_CGROUP_SKB:
^~~~
Warning level 3 was used: -Wimplicit-fallthrough=3
Notice that is much clearer to explicitly add breaks in each case
statement (that actually contains some code), rather than letting
the code to fall through.
This patch is part of the ongoing efforts to enable
-Wimplicit-fallthrough.
Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
When backtracking instructions to propagate precision bit for registers
and stack slots, one class of instructions (BPF_ST) weren't handled
causing extra stack slots to be propagated into parent state. Parent
state might not have that much stack allocated, though, which causes
warning on invalid stack slot usage.
This patch adds handling of BPF_ST instructions:
BPF_MEM | <size> | BPF_ST: *(size *) (dst_reg + off) = imm32
Reported-by: syzbot+4da3ff23081bafe74fc2@syzkaller.appspotmail.com
Fixes: b5dc0163d8 ("bpf: precise scalar_value tracking")
Cc: Alexei Starovoitov <ast@fb.com>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
kmsg_dump_get_buffer() is supposed to select all the youngest log
messages which fit into the provided buffer. It determines the correct
start index by using msg_print_text() with a NULL buffer to calculate
the size of each entry. However, when performing the actual writes,
msg_print_text() only writes the entry to the buffer if the written len
is lesser than the size of the buffer. So if the lengths of the
selected youngest log messages happen to precisely fill up the provided
buffer, the last log message is not included.
We don't want to modify msg_print_text() to fill up the buffer and start
returning a length which is equal to the size of the buffer, since
callers of its other users, such as kmsg_dump_get_line(), depend upon
the current behaviour.
Instead, fix kmsg_dump_get_buffer() to compensate for this.
For example, with the following two final prints:
[ 6.427502] AAAAAAAAAAAAA
[ 6.427769] BBBBBBBB12345
A dump of a 64-byte buffer filled by kmsg_dump_get_buffer(), before this
patch:
00000000: 3c 30 3e 5b 20 20 20 20 36 2e 35 32 32 31 39 37 <0>[ 6.522197
00000010: 5d 20 41 41 41 41 41 41 41 41 41 41 41 41 41 0a ] AAAAAAAAAAAAA.
00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
After this patch:
00000000: 3c 30 3e 5b 20 20 20 20 36 2e 34 35 36 36 37 38 <0>[ 6.456678
00000010: 5d 20 42 42 42 42 42 42 42 42 31 32 33 34 35 0a ] BBBBBBBB12345.
00000020: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
00000030: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................
Link: http://lkml.kernel.org/r/20190711142937.4083-1-vincent.whitchurch@axis.com
Fixes: e2ae715d66 ("kmsg - kmsg_dump() use iterator to receive log buffer content")
To: rostedt@goodmis.org
Cc: linux-kernel@vger.kernel.org
Cc: <stable@vger.kernel.org> # v3.5+
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Pull livepatching updates from Jiri Kosina:
- stacktrace handling improvements from Miroslav benes
- debug output improvements from Petr Mladek
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
livepatch: Remove duplicate warning about missing reliable stacktrace support
Revert "livepatch: Remove reliable stacktrace check in klp_try_switch_task()"
stacktrace: Remove weak version of save_stack_trace_tsk_reliable()
livepatch: Use static buffer for debugging messages under rq lock
livepatch: Remove stale kobj_added entries from kernel-doc descriptions
Pull timer fixes from Thomas Gleixner:
"Two small fixes from the timer departement:
- Prevent the compiler from converting the nanoseconds adjustment
loop in the VDSO update function to a division (__udivdi3) by using
the __iter_div_u64_rem() inline function which exists to prevent
exactly that problem.
- Fix the wrong argument order of the GENMASK macro in the NPCM timer
driver"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timekeeping/vsyscall: Use __iter_div_u64_rem()
clocksource/drivers/npcm: Fix misuse of GENMASK macro
Pull stacktrace fix from Thomas Gleixner:
"Fix yet another instance of kernel thread check which ignores that
kernel threads can call use_mm()"
* 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
stacktrace: Use PF_KTHREAD to check for kernel threads
Pull networking updates from David Miller:
"Some highlights from this development cycle:
1) Big refactoring of ipv6 route and neigh handling to support
nexthop objects configurable as units from userspace. From David
Ahern.
2) Convert explored_states in BPF verifier into a hash table,
significantly decreased state held for programs with bpf2bpf
calls, from Alexei Starovoitov.
3) Implement bpf_send_signal() helper, from Yonghong Song.
4) Various classifier enhancements to mvpp2 driver, from Maxime
Chevallier.
5) Add aRFS support to hns3 driver, from Jian Shen.
6) Fix use after free in inet frags by allocating fqdirs dynamically
and reworking how rhashtable dismantle occurs, from Eric Dumazet.
7) Add act_ctinfo packet classifier action, from Kevin
Darbyshire-Bryant.
8) Add TFO key backup infrastructure, from Jason Baron.
9) Remove several old and unused ISDN drivers, from Arnd Bergmann.
10) Add devlink notifications for flash update status to mlxsw driver,
from Jiri Pirko.
11) Lots of kTLS offload infrastructure fixes, from Jakub Kicinski.
12) Add support for mv88e6250 DSA chips, from Rasmus Villemoes.
13) Various enhancements to ipv6 flow label handling, from Eric
Dumazet and Willem de Bruijn.
14) Support TLS offload in nfp driver, from Jakub Kicinski, Dirk van
der Merwe, and others.
15) Various improvements to axienet driver including converting it to
phylink, from Robert Hancock.
16) Add PTP support to sja1105 DSA driver, from Vladimir Oltean.
17) Add mqprio qdisc offload support to dpaa2-eth, from Ioana
Radulescu.
18) Add devlink health reporting to mlx5, from Moshe Shemesh.
19) Convert stmmac over to phylink, from Jose Abreu.
20) Add PTP PHC (Physical Hardware Clock) support to mlxsw, from
Shalom Toledo.
21) Add nftables SYNPROXY support, from Fernando Fernandez Mancera.
22) Convert tcp_fastopen over to use SipHash, from Ard Biesheuvel.
23) Track spill/fill of constants in BPF verifier, from Alexei
Starovoitov.
24) Support bounded loops in BPF, from Alexei Starovoitov.
25) Various page_pool API fixes and improvements, from Jesper Dangaard
Brouer.
26) Just like ipv4, support ref-countless ipv6 route handling. From
Wei Wang.
27) Support VLAN offloading in aquantia driver, from Igor Russkikh.
28) Add AF_XDP zero-copy support to mlx5, from Maxim Mikityanskiy.
29) Add flower GRE encap/decap support to nfp driver, from Pieter
Jansen van Vuuren.
30) Protect against stack overflow when using act_mirred, from John
Hurley.
31) Allow devmap map lookups from eBPF, from Toke Høiland-Jørgensen.
32) Use page_pool API in netsec driver, Ilias Apalodimas.
33) Add Google gve network driver, from Catherine Sullivan.
34) More indirect call avoidance, from Paolo Abeni.
35) Add kTLS TX HW offload support to mlx5, from Tariq Toukan.
36) Add XDP_REDIRECT support to bnxt_en, from Andy Gospodarek.
37) Add MPLS manipulation actions to TC, from John Hurley.
38) Add sending a packet to connection tracking from TC actions, and
then allow flower classifier matching on conntrack state. From
Paul Blakey.
39) Netfilter hw offload support, from Pablo Neira Ayuso"
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (2080 commits)
net/mlx5e: Return in default case statement in tx_post_resync_params
mlx5: Return -EINVAL when WARN_ON_ONCE triggers in mlx5e_tls_resync().
net: dsa: add support for BRIDGE_MROUTER attribute
pkt_sched: Include const.h
net: netsec: remove static declaration for netsec_set_tx_de()
net: netsec: remove superfluous if statement
netfilter: nf_tables: add hardware offload support
net: flow_offload: rename tc_cls_flower_offload to flow_cls_offload
net: flow_offload: add flow_block_cb_is_busy() and use it
net: sched: remove tcf block API
drivers: net: use flow block API
net: sched: use flow block API
net: flow_offload: add flow_block_cb_{priv, incref, decref}()
net: flow_offload: add list handling functions
net: flow_offload: add flow_block_cb_alloc() and flow_block_cb_free()
net: flow_offload: rename TCF_BLOCK_BINDER_TYPE_* to FLOW_BLOCK_BINDER_TYPE_*
net: flow_offload: rename TC_BLOCK_{UN}BIND to FLOW_BLOCK_{UN}BIND
net: flow_offload: add flow_block_cb_setup_simple()
net: hisilicon: Add an tx_desc to adapt HI13X1_GMAC
net: hisilicon: Add an rx_desc to adapt HI13X1_GMAC
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXSMhhgAKCRCRxhvAZXjc
or7kAP9VzDcQaK/WoDd2ezh2C7Wh5hNy9z/qJVCa6Tb+N+g1UgEAxbhFUg55uGOA
JNf7fGar5JF5hBMIXR+NqOi1/sb4swg=
=ELWo
-----END PGP SIGNATURE-----
Merge tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull clone3 system call from Christian Brauner:
"This adds the clone3 syscall which is an extensible successor to clone
after we snagged the last flag with CLONE_PIDFD during the 5.2 merge
window for clone(). It cleanly supports all of the flags from clone()
and thus all legacy workloads.
There are few user visible differences between clone3 and clone.
First, CLONE_DETACHED will cause EINVAL with clone3 so we can reuse
this flag. Second, the CSIGNAL flag is deprecated and will cause
EINVAL to be reported. It is superseeded by a dedicated "exit_signal"
argument in struct clone_args thus freeing up even more flags. And
third, clone3 gives CLONE_PIDFD a dedicated return argument in struct
clone_args instead of abusing CLONE_PARENT_SETTID's parent_tidptr
argument.
The clone3 uapi is designed to be easy to handle on 32- and 64 bit:
/* uapi */
struct clone_args {
__aligned_u64 flags;
__aligned_u64 pidfd;
__aligned_u64 child_tid;
__aligned_u64 parent_tid;
__aligned_u64 exit_signal;
__aligned_u64 stack;
__aligned_u64 stack_size;
__aligned_u64 tls;
};
and a separate kernel struct is used that uses proper kernel typing:
/* kernel internal */
struct kernel_clone_args {
u64 flags;
int __user *pidfd;
int __user *child_tid;
int __user *parent_tid;
int exit_signal;
unsigned long stack;
unsigned long stack_size;
unsigned long tls;
};
The system call comes with a size argument which enables the kernel to
detect what version of clone_args userspace is passing in. clone3
validates that any additional bytes a given kernel does not know about
are set to zero and that the size never exceeds a page.
A nice feature is that this patchset allowed us to cleanup and
simplify various core kernel codepaths in kernel/fork.c by making the
internal _do_fork() function take struct kernel_clone_args even for
legacy clone().
This patch also unblocks the time namespace patchset which wants to
introduce a new CLONE_TIMENS flag.
Note, that clone3 has only been wired up for x86{_32,64}, arm{64}, and
xtensa. These were the architectures that did not require special
massaging.
Other architectures treat fork-like system calls individually and
after some back and forth neither Arnd nor I felt confident that we
dared to add clone3 unconditionally to all architectures. We agreed to
leave this up to individual architecture maintainers. This is why
there's an additional patch that introduces __ARCH_WANT_SYS_CLONE3
which any architecture can set once it has implemented support for
clone3. The patch also adds a cond_syscall(clone3) for architectures
such as nios2 or h8300 that generate their syscall table by simply
including asm-generic/unistd.h. The hope is to get rid of
__ARCH_WANT_SYS_CLONE3 and cond_syscall() rather soon"
* tag 'clone3-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
arch: handle arches who do not yet define clone3
arch: wire-up clone3() syscall
fork: add clone3
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXSMhUgAKCRCRxhvAZXjc
okkiAQC3Hlg/O2JoIb4PqgEvBkpHSdVxyuWagn0ksjACW9ANKQEAl5OadMhvOq16
UHGhKlpE/M8HflknIffoEGlIAWHrdwU=
=7kP5
-----END PGP SIGNATURE-----
Merge tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull pidfd updates from Christian Brauner:
"This adds two main features.
- First, it adds polling support for pidfds. This allows process
managers to know when a (non-parent) process dies in a race-free
way.
The notification mechanism used follows the same logic that is
currently used when the parent of a task is notified of a child's
death. With this patchset it is possible to put pidfds in an
{e}poll loop and get reliable notifications for process (i.e.
thread-group) exit.
- The second feature compliments the first one by making it possible
to retrieve pollable pidfds for processes that were not created
using CLONE_PIDFD.
A lot of processes get created with traditional PID-based calls
such as fork() or clone() (without CLONE_PIDFD). For these
processes a caller can currently not create a pollable pidfd. This
is a problem for Android's low memory killer (LMK) and service
managers such as systemd.
Both patchsets are accompanied by selftests.
It's perhaps worth noting that the work done so far and the work done
in this branch for pidfd_open() and polling support do already see
some adoption:
- Android is in the process of backporting this work to all their LTS
kernels [1]
- Service managers make use of pidfd_send_signal but will need to
wait until we enable waiting on pidfds for full adoption.
- And projects I maintain make use of both pidfd_send_signal and
CLONE_PIDFD [2] and will use polling support and pidfd_open() too"
[1] https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.9+backport%22https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.14+backport%22https://android-review.googlesource.com/q/topic:%22pidfd+polling+support+4.19+backport%22
[2] aab6e3eb73/src/lxc/start.c (L1753)
* tag 'pidfd-updates-v5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
tests: add pidfd_open() tests
arch: wire-up pidfd_open()
pid: add pidfd_open()
pidfd: add polling selftests
pidfd: add polling support
On 32-bit x86 when building with clang-9, the 'division' loop gets turned
back into an inefficient division that causes a link error:
kernel/time/vsyscall.o: In function `update_vsyscall':
vsyscall.c:(.text+0xe3): undefined reference to `__udivdi3'
Use the existing __iter_div_u64_rem() function which is used to address the
same issue in other places.
Fixes: 44f57d788e ("timekeeping: Provide a generic update_vsyscall() implementation")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Link: https://lkml.kernel.org/r/20190710130206.1670830-1-arnd@arndb.de
- A fair pile of RST conversions, many from Mauro. These create more
than the usual number of simple but annoying merge conflicts with other
trees, unfortunately. He has a lot more of these waiting on the wings
that, I think, will go to you directly later on.
- A new document on how to use merges and rebases in kernel repos, and one
on Spectre vulnerabilities.
- Various improvements to the build system, including automatic markup of
function() references because some people, for reasons I will never
understand, were of the opinion that :c:func:``function()`` is
unattractive and not fun to type.
- We now recommend using sphinx 1.7, but still support back to 1.4.
- Lots of smaller improvements, warning fixes, typo fixes, etc.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl0krAEPHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5Yg98H/AuLqO9LpOgUjF4LhyjxGPdzJkY9RExSJ7km
gznyreLCZgFaJR+AY6YDsd4Jw6OJlPbu1YM/Qo3C3WrZVFVhgL/s2ebvBgCo50A8
raAFd8jTf4/mGCHnAqRotAPQ3mETJUk315B66lBJ6Oc+YdpRhwXWq8ZW2bJxInFF
3HDvoFgMf0KhLuMHUkkL0u3fxH1iA+KvDu8diPbJYFjOdOWENz/CV8wqdVkXRSEW
DJxIq89h/7d+hIG3d1I7Nw+gibGsAdjSjKv4eRKauZs4Aoxd1Gpl62z0JNk6aT3m
dtq4joLdwScydonXROD/Twn2jsu4xYTrPwVzChomElMowW/ZBBY=
=D0eO
-----END PGP SIGNATURE-----
Merge tag 'docs-5.3' of git://git.lwn.net/linux
Pull Documentation updates from Jonathan Corbet:
"It's been a relatively busy cycle for docs:
- A fair pile of RST conversions, many from Mauro. These create more
than the usual number of simple but annoying merge conflicts with
other trees, unfortunately. He has a lot more of these waiting on
the wings that, I think, will go to you directly later on.
- A new document on how to use merges and rebases in kernel repos,
and one on Spectre vulnerabilities.
- Various improvements to the build system, including automatic
markup of function() references because some people, for reasons I
will never understand, were of the opinion that
:c:func:``function()`` is unattractive and not fun to type.
- We now recommend using sphinx 1.7, but still support back to 1.4.
- Lots of smaller improvements, warning fixes, typo fixes, etc"
* tag 'docs-5.3' of git://git.lwn.net/linux: (129 commits)
docs: automarkup.py: ignore exceptions when seeking for xrefs
docs: Move binderfs to admin-guide
Disable Sphinx SmartyPants in HTML output
doc: RCU callback locks need only _bh, not necessarily _irq
docs: format kernel-parameters -- as code
Doc : doc-guide : Fix a typo
platform: x86: get rid of a non-existent document
Add the RCU docs to the core-api manual
Documentation: RCU: Add TOC tree hooks
Documentation: RCU: Rename txt files to rst
Documentation: RCU: Convert RCU UP systems to reST
Documentation: RCU: Convert RCU linked list to reST
Documentation: RCU: Convert RCU basic concepts to reST
docs: filesystems: Remove uneeded .rst extension on toctables
scripts/sphinx-pre-install: fix out-of-tree build
docs: zh_CN: submitting-drivers.rst: Remove a duplicated Documentation/
Documentation: PGP: update for newer HW devices
Documentation: Add section about CPU vulnerabilities for Spectre
Documentation: platform: Delete x86-laptop-drivers.txt
docs: Note that :c:func: should no longer be used
...
Pull perf updates from Ingo Molnar:
"The main changes in this cycle on the kernel side were:
- CPU PMU and uncore driver updates to Intel Snow Ridge, IceLake,
KabyLake, AmberLake and WhiskeyLake CPUs.
- Rework the MSR probing infrastructure to make it more robust, make
it work better on virtualized systems and to better expose it on
sysfs.
- Rework PMU attributes group support based on the feedback from
Greg. The core sysfs patch that adds sysfs_update_groups() was
acked by Greg.
There's a lot of perf tooling changes as well, all around the place:
- vendor updates to Intel, cs-etm (ARM), ARM64, s390,
- various enhancements to Intel PT tooling support:
- Improve CBR (Core to Bus Ratio) packets support.
- Export power and ptwrite events to sqlite and postgresql.
- Add support for decoding PEBS via PT packets.
- Add support for samples to contain IPC ratio, collecting cycles
information from CYC packets, showing the IPC info periodically
- Allow using time ranges
- lots of updates to perf pmu, perf stat, perf trace, eBPF support,
perf record, perf diff, etc. - please see the shortlog and Git log
for details"
* 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (252 commits)
tools arch x86: Sync asm/cpufeatures.h with the with the kernel
tools build: Check if gettid() is available before providing helper
perf jvmti: Address gcc string overflow warning for strncpy()
perf python: Remove -fstack-protector-strong if clang doesn't have it
perf annotate TUI browser: Do not use member from variable within its own initialization
perf tests: Fix record+probe_libc_inet_pton.sh for powerpc64
perf evsel: Do not rely on errno values for precise_ip fallback
perf thread: Allow references to thread objects after machine__exit()
perf header: Assign proper ff->ph in perf_event__synthesize_features()
tools arch kvm: Sync kvm headers with the kernel sources
perf script: Allow specifying the files to process guest samples
perf tools metric: Don't include duration_time in group
perf list: Avoid extra : for --raw metrics
perf vendor events intel: Metric fixes for SKX/CLX
perf tools: Fix typos / broken sentences
perf jevents: Add support for Hisi hip08 L3C PMU aliasing
perf jevents: Add support for Hisi hip08 HHA PMU aliasing
perf jevents: Add support for Hisi hip08 DDRC PMU aliasing
perf pmu: Support more complex PMU event aliasing
perf diff: Documentation -c cycles option
...
-----BEGIN PGP SIGNATURE-----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=VSYT
-----END PGP SIGNATURE-----
Merge tag 'for-5.3/block-20190708' of git://git.kernel.dk/linux-block
Pull block updates from Jens Axboe:
"This is the main block updates for 5.3. Nothing earth shattering or
major in here, just fixes, additions, and improvements all over the
map. This contains:
- Series of documentation fixes (Bart)
- Optimization of the blk-mq ctx get/put (Bart)
- null_blk removal race condition fix (Bob)
- req/bio_op() cleanups (Chaitanya)
- Series cleaning up the segment accounting, and request/bio mapping
(Christoph)
- Series cleaning up the page getting/putting for bios (Christoph)
- block cgroup cleanups and moving it to where it is used (Christoph)
- block cgroup fixes (Tejun)
- Series of fixes and improvements to bcache, most notably a write
deadlock fix (Coly)
- blk-iolatency STS_AGAIN and accounting fixes (Dennis)
- Series of improvements and fixes to BFQ (Douglas, Paolo)
- debugfs_create() return value check removal for drbd (Greg)
- Use struct_size(), where appropriate (Gustavo)
- Two lighnvm fixes (Heiner, Geert)
- MD fixes, including a read balance and corruption fix (Guoqing,
Marcos, Xiao, Yufen)
- block opal shadow mbr additions (Jonas, Revanth)
- sbitmap compare-and-exhange improvemnts (Pavel)
- Fix for potential bio->bi_size overflow (Ming)
- NVMe pull requests:
- improved PCIe suspent support (Keith Busch)
- error injection support for the admin queue (Akinobu Mita)
- Fibre Channel discovery improvements (James Smart)
- tracing improvements including nvmetc tracing support (Minwoo Im)
- misc fixes and cleanups (Anton Eidelman, Minwoo Im, Chaitanya
Kulkarni)"
- Various little fixes and improvements to drivers and core"
* tag 'for-5.3/block-20190708' of git://git.kernel.dk/linux-block: (153 commits)
blk-iolatency: fix STS_AGAIN handling
block: nr_phys_segments needs to be zero for REQ_OP_WRITE_ZEROES
blk-mq: simplify blk_mq_make_request()
blk-mq: remove blk_mq_put_ctx()
sbitmap: Replace cmpxchg with xchg
block: fix .bi_size overflow
block: sed-opal: check size of shadow mbr
block: sed-opal: ioctl for writing to shadow mbr
block: sed-opal: add ioctl for done-mark of shadow mbr
block: never take page references for ITER_BVEC
direct-io: use bio_release_pages in dio_bio_complete
block_dev: use bio_release_pages in bio_unmap_user
block_dev: use bio_release_pages in blkdev_bio_end_io
iomap: use bio_release_pages in iomap_dio_bio_end_io
block: use bio_release_pages in bio_map_user_iov
block: use bio_release_pages in bio_unmap_user
block: optionally mark pages dirty in bio_release_pages
block: move the BIO_NO_PAGE_REF check into bio_release_pages
block: skd_main.c: Remove call to memset after dma_alloc_coherent
block: mtip32xx: Remove call to memset after dma_alloc_coherent
...
- Improve the handling of shared ACPI power resources in the PCI
bus type layer (Mika Westerberg).
- Make the PCI layer take link delays required by the PCIe spec
into account as appropriate and avoid polling devices in D3cold
for PME (Mika Westerberg).
- Fix some corner case issues in ACPI device power management and
in the PCI bus type layer, optimiza and clean up the handling of
runtime-suspended PCI devices during system-wide transitions to
sleep states (Rafael Wysocki).
- Rework hibernation handling in the ACPI core and the PCI bus type
to resume runtime-suspended devices before hibernation (which
allows some functional problems to be avoided) and fix some ACPI
power management issues related to hiberation (Rafael Wysocki).
- Extend the operating performance points (OPP) framework to support
a wider range of devices (Rajendra Nayak, Stehpen Boyd).
- Fix issues related to genpd_virt_devs and issues with platforms
using the set_opp() callback in the OPP framework (Viresh Kumar,
Dmitry Osipenko).
- Add new cpufreq driver for Raspberry Pi (Nicolas Saenz Julienne).
- Add new cpufreq driver for imx8m and imx7d chips (Leonard Crestez).
- Fix and clean up the pcc-cpufreq, brcmstb-avs-cpufreq, s5pv210,
and armada-37xx cpufreq drivers (David Arcari, Florian Fainelli,
Paweł Chmiel, YueHaibing).
- Clean up and fix the cpufreq core (Viresh Kumar, Daniel Lezcano).
- Fix minor issue in the ACPI system sleep support code and export
one function from it (Lenny Szubowicz, Dexuan Cui).
- Clean up assorted pieces of PM code and documentation (Kefeng Wang,
Andy Shevchenko, Bart Van Assche, Greg Kroah-Hartman, Fuqian Huang,
Geert Uytterhoeven, Mathieu Malaterre, Rafael Wysocki).
- Update the pm-graph utility to v5.4 (Todd Brandt).
- Fix and clean up the cpupower utility (Abhishek Goel, Nick Black).
-----BEGIN PGP SIGNATURE-----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=aBN3
-----END PGP SIGNATURE-----
Merge tag 'pm-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"These update PCI and ACPI power management (improved handling of ACPI
power resources and PCIe link delays, fixes related to corner cases,
hibernation handling rework), fix and extend the operating performance
points (OPP) framework, add new cpufreq drivers for Raspberry Pi and
imx8m chips, update some other cpufreq drivers, clean up assorted
pieces of PM code and documentation and update tools.
Specifics:
- Improve the handling of shared ACPI power resources in the PCI bus
type layer (Mika Westerberg).
- Make the PCI layer take link delays required by the PCIe spec into
account as appropriate and avoid polling devices in D3cold for PME
(Mika Westerberg).
- Fix some corner case issues in ACPI device power management and in
the PCI bus type layer, optimiza and clean up the handling of
runtime-suspended PCI devices during system-wide transitions to
sleep states (Rafael Wysocki).
- Rework hibernation handling in the ACPI core and the PCI bus type
to resume runtime-suspended devices before hibernation (which
allows some functional problems to be avoided) and fix some ACPI
power management issues related to hiberation (Rafael Wysocki).
- Extend the operating performance points (OPP) framework to support
a wider range of devices (Rajendra Nayak, Stehpen Boyd).
- Fix issues related to genpd_virt_devs and issues with platforms
using the set_opp() callback in the OPP framework (Viresh Kumar,
Dmitry Osipenko).
- Add new cpufreq driver for Raspberry Pi (Nicolas Saenz Julienne).
- Add new cpufreq driver for imx8m and imx7d chips (Leonard Crestez).
- Fix and clean up the pcc-cpufreq, brcmstb-avs-cpufreq, s5pv210, and
armada-37xx cpufreq drivers (David Arcari, Florian Fainelli, Paweł
Chmiel, YueHaibing).
- Clean up and fix the cpufreq core (Viresh Kumar, Daniel Lezcano).
- Fix minor issue in the ACPI system sleep support code and export
one function from it (Lenny Szubowicz, Dexuan Cui).
- Clean up assorted pieces of PM code and documentation (Kefeng Wang,
Andy Shevchenko, Bart Van Assche, Greg Kroah-Hartman, Fuqian Huang,
Geert Uytterhoeven, Mathieu Malaterre, Rafael Wysocki).
- Update the pm-graph utility to v5.4 (Todd Brandt).
- Fix and clean up the cpupower utility (Abhishek Goel, Nick Black)"
* tag 'pm-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (57 commits)
ACPI: PM: Make acpi_sleep_state_supported() non-static
PM: sleep: Drop dev_pm_skip_next_resume_phases()
ACPI: PM: Unexport acpi_device_get_power()
Documentation: ABI: power: Add missing newline at end of file
ACPI: PM: Drop unused function and function header
ACPI: PM: Introduce "poweroff" callbacks for ACPI PM domain and LPSS
ACPI: PM: Simplify and fix PM domain hibernation callbacks
PCI: PM: Simplify bus-level hibernation callbacks
PM: ACPI/PCI: Resume all devices during hibernation
cpufreq: Avoid calling cpufreq_verify_current_freq() from handle_update()
cpufreq: Consolidate cpufreq_update_current_freq() and __cpufreq_get()
kernel: power: swap: use kzalloc() instead of kmalloc() followed by memset()
cpufreq: Don't skip frequency validation for has_target() drivers
PCI: PM/ACPI: Refresh all stale power state data in pci_pm_complete()
PCI / ACPI: Add _PR0 dependent devices
ACPI / PM: Introduce concept of a _PR0 dependent device
PCI / ACPI: Use cached ACPI device state to get PCI device power state
ACPI: PM: Allow transitions to D0 to occur in special cases
ACPI: PM: Avoid evaluating _PS3 on transitions from D3hot to D3cold
cpufreq: Use has_target() instead of !setpolicy
...
Objtool previously ignored ___bpf_prog_run() because it didn't understand
the jump table. This resulted in the ORC unwinder not being able to unwind
through non-JIT BPF code.
Now that objtool knows how to read jump tables, remove the whitelist and
annotate the jump table so objtool can recognize it.
Also add an additional "const" to the jump table definition to clarify that
the text pointers are constant. Otherwise GCC sets the section writable
flag and the assembler spits out warnings.
Fixes: d15d356887 ("perf/x86: Make perf callchains work without CONFIG_FRAME_POINTER")
Reported-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Kairui Song <kasong@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lkml.kernel.org/r/881939122b88f32be4c374d248c09d7527a87e35.1561685471.git.jpoimboe@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull force_sig() argument change from Eric Biederman:
"A source of error over the years has been that force_sig has taken a
task parameter when it is only safe to use force_sig with the current
task.
The force_sig function is built for delivering synchronous signals
such as SIGSEGV where the userspace application caused a synchronous
fault (such as a page fault) and the kernel responded with a signal.
Because the name force_sig does not make this clear, and because the
force_sig takes a task parameter the function force_sig has been
abused for sending other kinds of signals over the years. Slowly those
have been fixed when the oopses have been tracked down.
This set of changes fixes the remaining abusers of force_sig and
carefully rips out the task parameter from force_sig and friends
making this kind of error almost impossible in the future"
* 'siginfo-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (27 commits)
signal/x86: Move tsk inside of CONFIG_MEMORY_FAILURE in do_sigbus
signal: Remove the signal number and task parameters from force_sig_info
signal: Factor force_sig_info_to_task out of force_sig_info
signal: Generate the siginfo in force_sig
signal: Move the computation of force into send_signal and correct it.
signal: Properly set TRACE_SIGNAL_LOSE_INFO in __send_signal
signal: Remove the task parameter from force_sig_fault
signal: Use force_sig_fault_to_task for the two calls that don't deliver to current
signal: Explicitly call force_sig_fault on current
signal/unicore32: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from __do_user_fault
signal/arm: Remove tsk parameter from ptrace_break
signal/nds32: Remove tsk parameter from send_sigtrap
signal/riscv: Remove tsk parameter from do_trap
signal/sh: Remove tsk parameter from force_sig_info_fault
signal/um: Remove task parameter from send_sigtrap
signal/x86: Remove task parameter from send_sigtrap
signal: Remove task parameter from force_sig_mceerr
signal: Remove task parameter from force_sig
signal: Remove task parameter from force_sigsegv
...
Pull cgroup updates from Tejun Heo:
"Documentation updates and the addition of cgroup_parse_float() which
will be used by new controllers including blk-iocost"
* 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
docs: cgroup-v1: convert docs to ReST and rename to *.rst
cgroup: Move cgroup_parse_float() implementation out of CONFIG_SYSFS
cgroup: add cgroup_parse_float()
Pull workqueue updates from Tejun Heo:
"Just a couple cleanup patches. No functional changes."
* 'for-5.3' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Remove GPF argument from alloc_workqueue_attrs()
workqueue: Make alloc/apply/free_workqueue_attrs() static
Pull integrity updates from Mimi Zohar:
"Bug fixes, code clean up, and new features:
- IMA policy rules can be defined in terms of LSM labels, making the
IMA policy dependent on LSM policy label changes, in particular LSM
label deletions. The new environment, in which IMA-appraisal is
being used, frequently updates the LSM policy and permits LSM label
deletions.
- Prevent an mmap'ed shared file opened for write from also being
mmap'ed execute. In the long term, making this and other similar
changes at the VFS layer would be preferable.
- The IMA per policy rule template format support is needed for a
couple of new/proposed features (eg. kexec boot command line
measurement, appended signatures, and VFS provided file hashes).
- Other than the "boot-aggregate" record in the IMA measuremeent
list, all other measurements are of file data. Measuring and
storing the kexec boot command line in the IMA measurement list is
the first buffer based measurement included in the measurement
list"
* 'next-integrity' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
integrity: Introduce struct evm_xattr
ima: Update MAX_TEMPLATE_NAME_LEN to fit largest reasonable definition
KEXEC: Call ima_kexec_cmdline to measure the boot command line args
IMA: Define a new template field buf
IMA: Define a new hook to measure the kexec boot command line arguments
IMA: support for per policy rule template formats
integrity: Fix __integrity_init_keyring() section mismatch
ima: Use designated initializers for struct ima_event_data
ima: use the lsm policy update notifier
LSM: switch to blocking policy update notifiers
x86/ima: fix the Kconfig dependency for IMA_ARCH_POLICY
ima: Make arch_policy_entry static
ima: prevent a file already mmap'ed write to be mmap'ed execute
x86/ima: check EFI SetupMode too
-----BEGIN PGP SIGNATURE-----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=Push
-----END PGP SIGNATURE-----
Merge tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull keyring namespacing from David Howells:
"These patches help make keys and keyrings more namespace aware.
Firstly some miscellaneous patches to make the process easier:
- Simplify key index_key handling so that the word-sized chunks
assoc_array requires don't have to be shifted about, making it
easier to add more bits into the key.
- Cache the hash value in the key so that we don't have to calculate
on every key we examine during a search (it involves a bunch of
multiplications).
- Allow keying_search() to search non-recursively.
Then the main patches:
- Make it so that keyring names are per-user_namespace from the point
of view of KEYCTL_JOIN_SESSION_KEYRING so that they're not
accessible cross-user_namespace.
keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEYRING_NAME for this.
- Move the user and user-session keyrings to the user_namespace
rather than the user_struct. This prevents them propagating
directly across user_namespaces boundaries (ie. the KEY_SPEC_*
flags will only pick from the current user_namespace).
- Make it possible to include the target namespace in which the key
shall operate in the index_key. This will allow the possibility of
multiple keys with the same description, but different target
domains to be held in the same keyring.
keyctl_capabilities() shows KEYCTL_CAPS1_NS_KEY_TAG for this.
- Make it so that keys are implicitly invalidated by removal of a
domain tag, causing them to be garbage collected.
- Institute a network namespace domain tag that allows keys to be
differentiated by the network namespace in which they operate. New
keys that are of a type marked 'KEY_TYPE_NET_DOMAIN' are assigned
the network domain in force when they are created.
- Make it so that the desired network namespace can be handed down
into the request_key() mechanism. This allows AFS, NFS, etc. to
request keys specific to the network namespace of the superblock.
This also means that the keys in the DNS record cache are
thenceforth namespaced, provided network filesystems pass the
appropriate network namespace down into dns_query().
For DNS, AFS and NFS are good, whilst CIFS and Ceph are not. Other
cache keyrings, such as idmapper keyrings, also need to set the
domain tag - for which they need access to the network namespace of
the superblock"
* tag 'keys-namespace-20190627' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
keys: Pass the network namespace into request_key mechanism
keys: Network namespace domain tag
keys: Garbage collect keys for which the domain has been removed
keys: Include target namespace in match criteria
keys: Move the user and user-session keyrings to the user_namespace
keys: Namespace keyring names
keys: Add a 'recurse' flag for keyring searches
keys: Cache the hash value to avoid lots of recalculation
keys: Simplify key description management
-----BEGIN PGP SIGNATURE-----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=c2FO
-----END PGP SIGNATURE-----
Merge tag 'keys-request-20190626' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull request_key improvements from David Howells:
"These are all request_key()-related, including a fix and some improvements:
- Fix the lack of a Link permission check on a key found by
request_key(), thereby enabling request_key() to link keys that
don't grant this permission to the target keyring (which must still
grant Write permission).
Note that the key must be in the caller's keyrings already to be
found.
- Invalidate used request_key authentication keys rather than
revoking them, so that they get cleaned up immediately rather than
hanging around till the expiry time is passed.
- Move the RCU locks outwards from the keyring search functions so
that a request_key_rcu() can be provided. This can be called in RCU
mode, so it can't sleep and can't upcall - but it can be called
from LOOKUP_RCU pathwalk mode.
- Cache the latest positive result of request_key*() temporarily in
task_struct so that filesystems that make a lot of request_key()
calls during pathwalk can take advantage of it to avoid having to
redo the searching. This requires CONFIG_KEYS_REQUEST_CACHE=y.
It is assumed that the key just found is likely to be used multiple
times in each step in an RCU pathwalk, and is likely to be reused
for the next step too.
Note that the cleanup of the cache is done on TIF_NOTIFY_RESUME,
just before userspace resumes, and on exit"
* tag 'keys-request-20190626' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
keys: Kill off request_key_async{,_with_auxdata}
keys: Cache result of request_key*() temporarily in task_struct
keys: Provide request_key_rcu()
keys: Move the RCU locks outwards from the keyring search functions
keys: Invalidate used request_key authentication keys
keys: Fix request_key() lack of Link perm check on found key
-----BEGIN PGP SIGNATURE-----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=Oy7N
-----END PGP SIGNATURE-----
Merge tag 'keys-misc-20190619' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs
Pull misc keyring updates from David Howells:
"These are some miscellaneous keyrings fixes and improvements:
- Fix a bunch of warnings from sparse, including missing RCU bits and
kdoc-function argument mismatches
- Implement a keyctl to allow a key to be moved from one keyring to
another, with the option of prohibiting key replacement in the
destination keyring.
- Grant Link permission to possessors of request_key_auth tokens so
that upcall servicing daemons can more easily arrange things such
that only the necessary auth key is passed to the actual service
program, and not all the auth keys a daemon might possesss.
- Improvement in lookup_user_key().
- Implement a keyctl to allow keyrings subsystem capabilities to be
queried.
The keyutils next branch has commits to make available, document and
test the move-key and capabilities code:
https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/log
They're currently on the 'next' branch"
* tag 'keys-misc-20190619' of git://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs:
keys: Add capability-checking keyctl function
keys: Reuse keyring_index_key::desc_len in lookup_user_key()
keys: Grant Link permission to possessers of request_key auth keys
keys: Add a keyctl to move a key between keyrings
keys: Hoist locking out of __key_link_begin()
keys: Break bits out of key_unlink()
keys: Change keyring_serialise_link_sem to a mutex
keys: sparse: Fix kdoc mismatches
keys: sparse: Fix incorrect RCU accesses
keys: sparse: Fix key_fs[ug]id_changed()
-----BEGIN PGP SIGNATURE-----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=8HBN
-----END PGP SIGNATURE-----
Merge tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"This pull request is a bit early, but with some vacation time coming
up I wanted to send this out now just in case the remote Internet Gods
decide not to smile on me once the merge window opens. The patchset
for v5.3 is pretty minor this time, the highlights include:
- When the audit daemon is sent a signal, ensure we deliver
information about the sender even when syscall auditing is not
enabled/supported.
- Add the ability to filter audit records based on network address
family.
- Tighten the audit field filtering restrictions on string based
fields.
- Cleanup the audit field filtering verification code.
- Remove a few BUG() calls from the audit code"
* tag 'audit-pr-20190702' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: remove the BUG() calls in the audit rule comparison functions
audit: enforce op for string fields
audit: add saddr_fam filter field
audit: re-structure audit field valid checks
audit: deliver signal_info regarless of syscall
Currently, kheaders_data.tar.xz contains some build scripts as well as
headers. None of them is needed in the header archive.
For ARCH=x86, this commit excludes the following from the archive:
arch/x86/include/asm/Kbuild
arch/x86/include/uapi/asm/Kbuild
include/asm-generic/Kbuild
include/config/auto.conf
include/config/kernel.release
include/config/tristate.conf
include/uapi/asm-generic/Kbuild
include/uapi/Kbuild
kernel/gen_kheaders.sh
This change is actually motivated for the planned header compile-testing
because it will generate more build artifacts, which should not be
included in the archive.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
The -R option of 'ls' is supposed to be used for directories.
-R, --recursive
list subdirectories recursively
Since 'find ... -type f' only matches to regular files, we do not
expect directories passed to the 'ls' command here.
Giving -R is harmless at least, but unneeded.
Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Pull scheduler updates from Ingo Molnar:
- Remove the unused per rq load array and all its infrastructure, by
Dietmar Eggemann.
- Add utilization clamping support by Patrick Bellasi. This is a
refinement of the energy aware scheduling framework with support for
boosting of interactive and capping of background workloads: to make
sure critical GUI threads get maximum frequency ASAP, and to make
sure background processing doesn't unnecessarily move to cpufreq
governor to higher frequencies and less energy efficient CPU modes.
- Add the bare minimum of tracepoints required for LISA EAS regression
testing, by Qais Yousef - which allows automated testing of various
power management features, including energy aware scheduling.
- Restructure the former tsk_nr_cpus_allowed() facility that the -rt
kernel used to modify the scheduler's CPU affinity logic such as
migrate_disable() - introduce the task->cpus_ptr value instead of
taking the address of &task->cpus_allowed directly - by Sebastian
Andrzej Siewior.
- Misc optimizations, fixes, cleanups and small enhancements - see the
Git log for details.
* 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (33 commits)
sched/uclamp: Add uclamp support to energy_compute()
sched/uclamp: Add uclamp_util_with()
sched/cpufreq, sched/uclamp: Add clamps for FAIR and RT tasks
sched/uclamp: Set default clamps for RT tasks
sched/uclamp: Reset uclamp values on RESET_ON_FORK
sched/uclamp: Extend sched_setattr() to support utilization clamping
sched/core: Allow sched_setattr() to use the current policy
sched/uclamp: Add system default clamps
sched/uclamp: Enforce last task's UCLAMP_MAX
sched/uclamp: Add bucket local max tracking
sched/uclamp: Add CPU's clamp buckets refcounting
sched/fair: Rename weighted_cpuload() to cpu_runnable_load()
sched/debug: Export the newly added tracepoints
sched/debug: Add sched_overutilized tracepoint
sched/debug: Add new tracepoint to track PELT at se level
sched/debug: Add new tracepoints to track PELT at rq level
sched/debug: Add a new sched_trace_*() helper functions
sched/autogroup: Make autogroup_path() always available
sched/wait: Deduplicate code with do-while
sched/topology: Remove unused 'sd' parameter from arch_scale_cpu_capacity()
...
Pull locking updates from Ingo Molnar:
"The main changes in this cycle are:
- rwsem scalability improvements, phase #2, by Waiman Long, which are
rather impressive:
"On a 2-socket 40-core 80-thread Skylake system with 40 reader
and writer locking threads, the min/mean/max locking operations
done in a 5-second testing window before the patchset were:
40 readers, Iterations Min/Mean/Max = 1,807/1,808/1,810
40 writers, Iterations Min/Mean/Max = 1,807/50,344/151,255
After the patchset, they became:
40 readers, Iterations Min/Mean/Max = 30,057/31,359/32,741
40 writers, Iterations Min/Mean/Max = 94,466/95,845/97,098"
There's a lot of changes to the locking implementation that makes
it similar to qrwlock, including owner handoff for more fair
locking.
Another microbenchmark shows how across the spectrum the
improvements are:
"With a locking microbenchmark running on 5.1 based kernel, the
total locking rates (in kops/s) on a 2-socket Skylake system
with equal numbers of readers and writers (mixed) before and
after this patchset were:
# of Threads Before Patch After Patch
------------ ------------ -----------
2 2,618 4,193
4 1,202 3,726
8 802 3,622
16 729 3,359
32 319 2,826
64 102 2,744"
The changes are extensive and the patch-set has been through
several iterations addressing various locking workloads. There
might be more regressions, but unless they are pathological I
believe we want to use this new implementation as the baseline
going forward.
- jump-label optimizations by Daniel Bristot de Oliveira: the primary
motivation was to remove IPI disturbance of isolated RT-workload
CPUs, which resulted in the implementation of batched jump-label
updates. Beyond the improvement of the real-time characteristics
kernel, in one test this patchset improved static key update
overhead from 57 msecs to just 1.4 msecs - which is a nice speedup
as well.
- atomic64_t cross-arch type cleanups by Mark Rutland: over the last
~10 years of atomic64_t existence the various types used by the
APIs only had to be self-consistent within each architecture -
which means they became wildly inconsistent across architectures.
Mark puts and end to this by reworking all the atomic64
implementations to use 's64' as the base type for atomic64_t, and
to ensure that this type is consistently used for parameters and
return values in the API, avoiding further problems in this area.
- A large set of small improvements to lockdep by Yuyang Du: type
cleanups, output cleanups, function return type and othr cleanups
all around the place.
- A set of percpu ops cleanups and fixes by Peter Zijlstra.
- Misc other changes - please see the Git log for more details"
* 'locking-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (82 commits)
locking/lockdep: increase size of counters for lockdep statistics
locking/atomics: Use sed(1) instead of non-standard head(1) option
locking/lockdep: Move mark_lock() inside CONFIG_TRACE_IRQFLAGS && CONFIG_PROVE_LOCKING
x86/jump_label: Make tp_vec_nr static
x86/percpu: Optimize raw_cpu_xchg()
x86/percpu, sched/fair: Avoid local_clock()
x86/percpu, x86/irq: Relax {set,get}_irq_regs()
x86/percpu: Relax smp_processor_id()
x86/percpu: Differentiate this_cpu_{}() and __this_cpu_{}()
locking/rwsem: Guard against making count negative
locking/rwsem: Adaptive disabling of reader optimistic spinning
locking/rwsem: Enable time-based spinning on reader-owned rwsem
locking/rwsem: Make rwsem->owner an atomic_long_t
locking/rwsem: Enable readers spinning on writer
locking/rwsem: Clarify usage of owner's nonspinaable bit
locking/rwsem: Wake up almost all readers in wait queue
locking/rwsem: More optimal RT task handling of null owner
locking/rwsem: Always release wait_lock before waking up tasks
locking/rwsem: Implement lock handoff to prevent lock starvation
locking/rwsem: Make rwsem_spin_on_owner() return owner state
...
Pull RCU updates from Ingo Molnar:
"The changes in this cycle are:
- RCU flavor consolidation cleanups and optmizations
- Documentation updates
- Miscellaneous fixes
- SRCU updates
- RCU-sync flavor consolidation
- Torture-test updates
- Linux-kernel memory-consistency-model updates, most notably the
addition of plain C-language accesses"
* 'core-rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (61 commits)
tools/memory-model: Improve data-race detection
tools/memory-model: Change definition of rcu-fence
tools/memory-model: Expand definition of barrier
tools/memory-model: Do not use "herd" to refer to "herd7"
tools/memory-model: Fix comment in MP+poonceonces.litmus
Documentation: atomic_t.txt: Explain ordering provided by smp_mb__{before,after}_atomic()
rcu: Don't return a value from rcu_assign_pointer()
rcu: Force inlining of rcu_read_lock()
rcu: Fix irritating whitespace error in rcu_assign_pointer()
rcu: Upgrade sync_exp_work_done() to smp_mb()
rcutorture: Upper case solves the case of the vanishing NULL pointer
torture: Suppress propagating trace_printk() warning
rcutorture: Dump trace buffer for callback pipe drain failures
torture: Add --trust-make to suppress "make clean"
torture: Make --cpus override idleness calculations
torture: Run kernel build in source directory
torture: Add function graph-tracing cheat sheet
torture: Capture qemu output
rcutorture: Tweak kvm options
rcutorture: Add trivial RCU implementation
...
Pull x96 apic updates from Thomas Gleixner:
"Updates for the x86 APIC interrupt handling and APIC timer:
- Fix a long standing issue with spurious interrupts which was caused
by the big vector management rework a few years ago. Robert Hodaszi
provided finally enough debug data and an excellent initial failure
analysis which allowed to understand the underlying issues.
This contains a change to the core interrupt management code which
is required to handle this correctly for the APIC/IO_APIC. The core
changes are NOOPs for most architectures except ARM64. ARM64 is not
impacted by the change as confirmed by Marc Zyngier.
- Newer systems allow to disable the PIT clock for power saving
causing panic in the timer interrupt delivery check of the IO/APIC
when the HPET timer is not enabled either. While the clock could be
turned on this would cause an endless whack a mole game to chase
the proper register in each affected chipset.
These systems provide the relevant frequencies for TSC, CPU and the
local APIC timer via CPUID and/or MSRs, which allows to avoid the
PIT/HPET based calibration. As the calibration code is the only
usage of the legacy timers on modern systems and is skipped anyway
when the frequencies are known already, there is no point in
setting up the PIT and actually checking for the interrupt delivery
via IO/APIC.
To achieve this on a wide variety of platforms, the CPUID/MSR based
frequency readout has been made more robust, which also allowed to
remove quite some workarounds which turned out to be not longer
required. Thanks to Daniel Drake for analysis, patches and
verification"
* 'x86-apic-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/irq: Seperate unused system vectors from spurious entry again
x86/irq: Handle spurious interrupt after shutdown gracefully
x86/ioapic: Implement irq_get_irqchip_state() callback
genirq: Add optional hardware synchronization for shutdown
genirq: Fix misleading synchronize_irq() documentation
genirq: Delay deactivation in free_irq()
x86/timer: Skip PIT initialization on modern chipsets
x86/apic: Use non-atomic operations when possible
x86/apic: Make apic_bsp_setup() static
x86/tsc: Set LAPIC timer period to crystal clock frequency
x86/apic: Rename 'lapic_timer_frequency' to 'lapic_timer_period'
x86/tsc: Use CPUID.0x16 to calculate missing crystal frequency
Pull timer updates from Thomas Gleixner:
"The timer and timekeeping departement delivers:
Core:
- The consolidation of the VDSO code into a generic library including
the conversion of x86 and ARM64. Conversion of ARM and MIPS are en
route through the relevant maintainer trees and should end up in
5.4.
This gets rid of the unnecessary different copies of the same code
and brings all architectures on the same level of VDSO
functionality.
- Make the NTP user space interface more robust by restricting the
TAI offset to prevent undefined behaviour. Includes a selftest.
- Validate user input in the compat settimeofday() syscall to catch
invalid values which would be turned into valid values by a
multiplication overflow
- Consolidate the time accessors
- Small fixes, improvements and cleanups all over the place
Drivers:
- Support for the NXP system counter, TI davinci timer
- Move the Microsoft HyperV clocksource/events code into the
drivers/clocksource directory so it can be shared between x86 and
ARM64.
- Overhaul of the Tegra driver
- Delay timer support for IXP4xx
- Small fixes, improvements and cleanups as usual"
* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (71 commits)
time: Validate user input in compat_settimeofday()
timer: Document TIMER_PINNED
clocksource/drivers: Continue making Hyper-V clocksource ISA agnostic
clocksource/drivers: Make Hyper-V clocksource ISA agnostic
MAINTAINERS: Fix Andy's surname and the directory entries of VDSO
hrtimer: Use a bullet for the returns bullet list
arm64: vdso: Fix compilation with clang older than 8
arm64: compat: Fix __arch_get_hw_counter() implementation
arm64: Fix __arch_get_hw_counter() implementation
lib/vdso: Make delta calculation work correctly
MAINTAINERS: Add entry for the generic VDSO library
arm64: compat: No need for pre-ARMv7 barriers on an ARMv8 system
arm64: vdso: Remove unnecessary asm-offsets.c definitions
vdso: Remove superfluous #ifdef __KERNEL__ in vdso/datapage.h
clocksource/drivers/davinci: Add support for clocksource
clocksource/drivers/davinci: Add support for clockevents
clocksource/drivers/tegra: Set up maximum-ticks limit properly
clocksource/drivers/tegra: Cycles can't be 0
clocksource/drivers/tegra: Restore base address before cleanup
clocksource/drivers/tegra: Add verbose definition for 1MHz constant
...
Pull irq updates from Thomas Gleixner:
"The irq departement provides the usual mixed bag:
Core:
- Further improvements to the irq timings code which aims to predict
the next interrupt for power state selection to achieve better
latency/power balance
- Add interrupt statistics to the core NMI handlers
- The usual small fixes and cleanups
Drivers:
- Support for Renesas RZ/A1, Annapurna Labs FIC, Meson-G12A SoC and
Amazon Gravition AMR/GIC interrupt controllers.
- Rework of the Renesas INTC controller driver
- ACPI support for Socionext SoCs
- Enhancements to the CSKY interrupt controller
- The usual small fixes and cleanups"
* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (39 commits)
irq/irqdomain: Fix comment typo
genirq: Update irq stats from NMI handlers
irqchip/gic-pm: Remove PM_CLK dependency
irqchip/al-fic: Introduce Amazon's Annapurna Labs Fabric Interrupt Controller Driver
dt-bindings: interrupt-controller: Add Amazon's Annapurna Labs FIC
softirq: Use __this_cpu_write() in takeover_tasklets()
irqchip/mbigen: Stop printing kernel addresses
irqchip/gic: Add dependency for ARM_GIC_MAX_NR
genirq/affinity: Remove unused argument from [__]irq_build_affinity_masks()
genirq/timings: Add selftest for next event computation
genirq/timings: Add selftest for irqs circular buffer
genirq/timings: Add selftest for circular array
genirq/timings: Encapsulate storing function
genirq/timings: Encapsulate timings push
genirq/timings: Optimize the period detection speed
genirq/timings: Fix timings buffer inspection
genirq/timings: Fix next event index function
irqchip/qcom: Use struct_size() in devm_kzalloc()
irqchip/irq-csky-mpintc: Remove unnecessary loop in interrupt handler
dt-bindings: interrupt-controller: Update csky mpintc
...
Pull SMP/hotplug updates from Thomas Gleixner:
"A small set of updates for SMP and CPU hotplug:
- Abort disabling secondary CPUs in the freezer when a wakeup is
pending instead of evaluating it only after all CPUs have been
offlined.
- Remove the shared annotation for the strict per CPU cfd_data in the
smp function call core code.
- Remove the return values of smp_call_function() and on_each_cpu()
as they are unconditionally 0. Fixup the few callers which actually
bothered to check the return value"
* 'smp-hotplug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
smp: Remove smp_call_function() and on_each_cpu() return values
smp: Do not mark call_function_data as shared
cpu/hotplug: Abort disabling secondary CPUs if wakeup is pending
cpu/hotplug: Fix notify_cpu_starting() reference in bringup_wait_for_ap()
- Improve stop_machine wait logic: replace cpu_relax_yield call in generic
stop_machine function with a weak stop_machine_yield function. This is
overridden on s390, which yields the current cpu to the neighbouring cpu
after a couple of retries, instead of blindly giving up the cpu to the
hipervisor. This significantly improves stop_machine performance on s390 in
overcommitted scenarios.
This includes common code changes which have been Acked by Peter Zijlstra
and Thomas Gleixner.
- Improve jump label transformation speed: transform jump labels without
using stop_machine.
- Refactoring of the vfio-ccw cp handling, simplifying the code and
avoiding unneeded allocating/copying.
- Various vfio-ccw fixes (ccw translation, state machine).
- Add support for vfio-ap queue interrupt control in the guest.
This includes s390 kvm changes which have been Acked by Christian
Borntraeger.
- Add protected virtualization support for virtio-ccw.
- Enforce both CONFIG_SMP and CONFIG_HOTPLUG_CPU, which allows to remove some
code which most likely isn't working at all, besides that s390 didn't even
compile for !CONFIG_SMP.
- Support for special flagged EP11 CPRBs for zcrypt.
- Handle PCI devices with no support for new MIO instructions.
- Avoid KASAN false positives in reworked stack unwinder.
- Couple of fixes for the QDIO layer.
- Convert s390 specific documentation to ReST format.
- Let s390 crypto modules return -ENODEV instead of -EOPNOTSUPP if hardware is
missing. This way our modules behave like most other modules and which is
also what systemd's systemd-modules-load.service expects.
- Replace defconfig with performance_defconfig, so there is one config file
less to maintain.
- Remove the SCLP call home device driver, which was never useful.
- Cleanups all over the place.
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEE3QHqV+H2a8xAv27vjYWKoQLXFBgFAl0iEpcACgkQjYWKoQLX
FBgtZwf8DOJ6COUG91jKP0RSDlc2YvIMBxopQ38ql1lIsTj5t6DvJ2z3X5uct1wy
6mMiF01VuyD4V4UXbTJQrihzNx7D4dUh47s2sS+diGHxJyXacVxlmjS5k+6pLIUO
AyLvtCcoqDPPiThqnSTZFRm/TcfO/25fCG/IdjrFGj1MD09wHpUCh16tmRPTGFlC
BWZeilDT77fVXnh7Ggn3JB0mQay5PAw2ODOxELHTUBaLmYF8RJPPVKBPmXGl9P1W
84ESm2p+iALGGWDiTOUad9eu8wyQci/V/R+hFgs0Bz/HRcjznNH5EVvfQNCD4VNF
g/PET10nIQYZv2BNdi0cwRjR9jCFbw==
=jp0i
-----END PGP SIGNATURE-----
Merge tag 's390-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Vasily Gorbik:
- Improve stop_machine wait logic: replace cpu_relax_yield call in
generic stop_machine function with a weak stop_machine_yield
function. This is overridden on s390, which yields the current cpu to
the neighbouring cpu after a couple of retries, instead of blindly
giving up the cpu to the hipervisor. This significantly improves
stop_machine performance on s390 in overcommitted scenarios.
This includes common code changes which have been Acked by Peter
Zijlstra and Thomas Gleixner.
- Improve jump label transformation speed: transform jump labels
without using stop_machine.
- Refactoring of the vfio-ccw cp handling, simplifying the code and
avoiding unneeded allocating/copying.
- Various vfio-ccw fixes (ccw translation, state machine).
- Add support for vfio-ap queue interrupt control in the guest. This
includes s390 kvm changes which have been Acked by Christian
Borntraeger.
- Add protected virtualization support for virtio-ccw.
- Enforce both CONFIG_SMP and CONFIG_HOTPLUG_CPU, which allows to
remove some code which most likely isn't working at all, besides that
s390 didn't even compile for !CONFIG_SMP.
- Support for special flagged EP11 CPRBs for zcrypt.
- Handle PCI devices with no support for new MIO instructions.
- Avoid KASAN false positives in reworked stack unwinder.
- Couple of fixes for the QDIO layer.
- Convert s390 specific documentation to ReST format.
- Let s390 crypto modules return -ENODEV instead of -EOPNOTSUPP if
hardware is missing. This way our modules behave like most other
modules and which is also what systemd's systemd-modules-load.service
expects.
- Replace defconfig with performance_defconfig, so there is one config
file less to maintain.
- Remove the SCLP call home device driver, which was never useful.
- Cleanups all over the place.
* tag 's390-5.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (83 commits)
docs: s390: s390dbf: typos and formatting, update crash command
docs: s390: unify and update s390dbf kdocs at debug.c
docs: s390: restore important non-kdoc parts of s390dbf.rst
vfio-ccw: Fix the conversion of Format-0 CCWs to Format-1
s390/pci: correctly handle MIO opt-out
s390/pci: deal with devices that have no support for MIO instructions
s390: ap: kvm: Enable PQAP/AQIC facility for the guest
s390: ap: implement PAPQ AQIC interception in kernel
vfio: ap: register IOMMU VFIO notifier
s390: ap: kvm: add PQAP interception for AQIC
s390/unwind: cleanup unused READ_ONCE_TASK_STACK
s390/kasan: avoid false positives during stack unwind
s390/qdio: don't touch the dsci in tiqdio_add_input_queues()
s390/qdio: (re-)initialize tiqdio list entries
s390/dasd: Fix a precision vs width bug in dasd_feature_list()
s390/cio: introduce driver_override on the css bus
vfio-ccw: make convert_ccw0_to_ccw1 static
vfio-ccw: Remove copy_ccw_from_iova()
vfio-ccw: Factor out the ccw0-to-ccw1 transition
vfio-ccw: Copy CCW data outside length calculation
...
- arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}
- Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
manage the permissions of executable vmalloc regions more strictly
- Slight performance improvement by keeping softirqs enabled while
touching the FPSIMD/SVE state (kernel_neon_begin/end)
- Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new XAFLAG
and AXFLAG instructions for floating point comparison flags
manipulation) and FRINT (rounding floating point numbers to integers)
- Re-instate ARM64_PSEUDO_NMI support which was previously marked as
BROKEN due to some bugs (now fixed)
- Improve parking of stopped CPUs and implement an arm64-specific
panic_smp_self_stop() to avoid warning on not being able to stop
secondary CPUs during panic
- perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
platforms
- perf: DDR performance monitor support for iMX8QXP
- cache_line_size() can now be set from DT or ACPI/PPTT if provided to
cope with a system cache info not exposed via the CPUID registers
- Avoid warning on hardware cache line size greater than
ARCH_DMA_MINALIGN if the system is fully coherent
- arm64 do_page_fault() and hugetlb cleanups
- Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)
- Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the 'arm_boot_flags'
introduced in 5.1)
- CONFIG_RANDOMIZE_BASE now enabled in defconfig
- Allow the selection of ARM64_MODULE_PLTS, currently only done via
RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
over into the vmalloc area
- Make ZONE_DMA32 configurable
-----BEGIN PGP SIGNATURE-----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=0TDT
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 updates from Catalin Marinas:
- arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}
- Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
manage the permissions of executable vmalloc regions more strictly
- Slight performance improvement by keeping softirqs enabled while
touching the FPSIMD/SVE state (kernel_neon_begin/end)
- Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new
XAFLAG and AXFLAG instructions for floating point comparison flags
manipulation) and FRINT (rounding floating point numbers to integers)
- Re-instate ARM64_PSEUDO_NMI support which was previously marked as
BROKEN due to some bugs (now fixed)
- Improve parking of stopped CPUs and implement an arm64-specific
panic_smp_self_stop() to avoid warning on not being able to stop
secondary CPUs during panic
- perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
platforms
- perf: DDR performance monitor support for iMX8QXP
- cache_line_size() can now be set from DT or ACPI/PPTT if provided to
cope with a system cache info not exposed via the CPUID registers
- Avoid warning on hardware cache line size greater than
ARCH_DMA_MINALIGN if the system is fully coherent
- arm64 do_page_fault() and hugetlb cleanups
- Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)
- Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the
'arm_boot_flags' introduced in 5.1)
- CONFIG_RANDOMIZE_BASE now enabled in defconfig
- Allow the selection of ARM64_MODULE_PLTS, currently only done via
RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
over into the vmalloc area
- Make ZONE_DMA32 configurable
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits)
perf: arm_spe: Enable ACPI/Platform automatic module loading
arm_pmu: acpi: spe: Add initial MADT/SPE probing
ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens
ACPI/PPTT: Modify node flag detection to find last IDENTICAL
x86/entry: Simplify _TIF_SYSCALL_EMU handling
arm64: rename dump_instr as dump_kernel_instr
arm64/mm: Drop [PTE|PMD]_TYPE_FAULT
arm64: Implement panic_smp_self_stop()
arm64: Improve parking of stopped CPUs
arm64: Expose FRINT capabilities to userspace
arm64: Expose ARMv8.5 CondM capability to userspace
arm64: defconfig: enable CONFIG_RANDOMIZE_BASE
arm64: ARM64_MODULES_PLTS must depend on MODULES
arm64: bpf: do not allocate executable memory
arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages
arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP
arm64: module: create module allocations without exec permissions
arm64: Allow user selection of ARM64_MODULE_PLTS
acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
arm64: Allow selecting Pseudo-NMI again
...
If CONFIG_NET is not set and CONFIG_CGROUP_BPF=y,
gcc building fails:
kernel/bpf/cgroup.o: In function `cg_sockopt_func_proto':
cgroup.c:(.text+0x237e): undefined reference to `bpf_sk_storage_get_proto'
cgroup.c:(.text+0x2394): undefined reference to `bpf_sk_storage_delete_proto'
kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_getsockopt':
(.text+0x2a1f): undefined reference to `lock_sock_nested'
(.text+0x2ca2): undefined reference to `release_sock'
kernel/bpf/cgroup.o: In function `__cgroup_bpf_run_filter_setsockopt':
(.text+0x3006): undefined reference to `lock_sock_nested'
(.text+0x32bb): undefined reference to `release_sock'
Reported-by: Hulk Robot <hulkci@huawei.com>
Suggested-by: Stanislav Fomichev <sdf@fomichev.me>
Fixes: 0d01da6afc ("bpf: implement getsockopt and setsockopt hooks")
Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Acked-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
* pm-sleep:
PM: sleep: Drop dev_pm_skip_next_resume_phases()
ACPI: PM: Drop unused function and function header
ACPI: PM: Introduce "poweroff" callbacks for ACPI PM domain and LPSS
ACPI: PM: Simplify and fix PM domain hibernation callbacks
PCI: PM: Simplify bus-level hibernation callbacks
PM: ACPI/PCI: Resume all devices during hibernation
kernel: power: swap: use kzalloc() instead of kmalloc() followed by memset()
PM: sleep: Update struct wakeup_source documentation
drivers: base: power: remove wakeup_sources_stats_dentry variable
PM: suspend: Rename pm_suspend_via_s2idle()
PM: sleep: Show how long dpm_suspend_start() and dpm_suspend_end() take
PM: hibernate: powerpc: Expose pfn_is_nosave() prototype
The user value is validated after converting the timeval to a timespec, but
for a wide range of negative tv_usec values the multiplication overflow turns
them in positive numbers. So the 'validated later' is not catching the
invalid input.
Signed-off-by: zhengbin <zhengbin13@huawei.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1562460701-113301-1-git-send-email-zhengbin13@huawei.com
The NMI handlers handle_percpu_devid_fasteoi_nmi() and handle_fasteoi_nmi()
do not update the interrupt counts. Due to that the NMI interrupt count
does not show up correctly in /proc/interrupts.
Add the statistics and treat the NMI handlers in the same way as per cpu
interrupts and prevent them from updating irq_desc::tot_count as this might
be corrupted due to concurrency.
[ tglx: Massaged changelog ]
Fixes: 2dcf1fbcad ("genirq: Provide NMI handlers")
Signed-off-by: Shijith Thotton <sthotton@marvell.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/1562313336-11888-1-git-send-email-sthotton@marvell.com
Daniel Borkmann says:
====================
pull-request: bpf-next 2019-07-03
The following pull-request contains BPF updates for your *net-next* tree.
There is a minor merge conflict in mlx5 due to 8960b38932 ("linux/dim:
Rename externally used net_dim members") which has been pulled into your
tree in the meantime, but resolution seems not that bad ... getting current
bpf-next out now before there's coming more on mlx5. ;) I'm Cc'ing Saeed
just so he's aware of the resolution below:
** First conflict in drivers/net/ethernet/mellanox/mlx5/core/en_main.c:
<<<<<<< HEAD
static int mlx5e_open_cq(struct mlx5e_channel *c,
struct dim_cq_moder moder,
struct mlx5e_cq_param *param,
struct mlx5e_cq *cq)
=======
int mlx5e_open_cq(struct mlx5e_channel *c, struct net_dim_cq_moder moder,
struct mlx5e_cq_param *param, struct mlx5e_cq *cq)
>>>>>>> e5a3e259ef
Resolution is to take the second chunk and rename net_dim_cq_moder into
dim_cq_moder. Also the signature for mlx5e_open_cq() in ...
drivers/net/ethernet/mellanox/mlx5/core/en.h +977
... and in mlx5e_open_xsk() ...
drivers/net/ethernet/mellanox/mlx5/core/en/xsk/setup.c +64
... needs the same rename from net_dim_cq_moder into dim_cq_moder.
** Second conflict in drivers/net/ethernet/mellanox/mlx5/core/en_main.c:
<<<<<<< HEAD
int cpu = cpumask_first(mlx5_comp_irq_get_affinity_mask(priv->mdev, ix));
struct dim_cq_moder icocq_moder = {0, 0};
struct net_device *netdev = priv->netdev;
struct mlx5e_channel *c;
unsigned int irq;
=======
struct net_dim_cq_moder icocq_moder = {0, 0};
>>>>>>> e5a3e259ef
Take the second chunk and rename net_dim_cq_moder into dim_cq_moder
as well.
Let me know if you run into any issues. Anyway, the main changes are:
1) Long-awaited AF_XDP support for mlx5e driver, from Maxim.
2) Addition of two new per-cgroup BPF hooks for getsockopt and
setsockopt along with a new sockopt program type which allows more
fine-grained pass/reject settings for containers. Also add a sock_ops
callback that can be selectively enabled on a per-socket basis and is
executed for every RTT to help tracking TCP statistics, both features
from Stanislav.
3) Follow-up fix from loops in precision tracking which was not propagating
precision marks and as a result verifier assumed that some branches were
not taken and therefore wrongly removed as dead code, from Alexei.
4) Fix BPF cgroup release synchronization race which could lead to a
double-free if a leaf's cgroup_bpf object is released and a new BPF
program is attached to the one of ancestor cgroups in parallel, from Roman.
5) Support for bulking XDP_TX on veth devices which improves performance
in some cases by around 9%, from Toshiaki.
6) Allow for lookups into BPF devmap and improve feedback when calling into
bpf_redirect_map() as lookup is now performed right away in the helper
itself, from Toke.
7) Add support for fq's Earliest Departure Time to the Host Bandwidth
Manager (HBM) sample BPF program, from Lawrence.
8) Various cleanups and minor fixes all over the place from many others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Fix two issues:
When called for PTRACE_TRACEME, ptrace_link() would obtain an RCU
reference to the parent's objective credentials, then give that pointer
to get_cred(). However, the object lifetime rules for things like
struct cred do not permit unconditionally turning an RCU reference into
a stable reference.
PTRACE_TRACEME records the parent's credentials as if the parent was
acting as the subject, but that's not the case. If a malicious
unprivileged child uses PTRACE_TRACEME and the parent is privileged, and
at a later point, the parent process becomes attacker-controlled
(because it drops privileges and calls execve()), the attacker ends up
with control over two processes with a privileged ptrace relationship,
which can be abused to ptrace a suid binary and obtain root privileges.
Fix both of these by always recording the credentials of the process
that is requesting the creation of the ptrace relationship:
current_cred() can't change under us, and current is the proper subject
for access control.
This change is theoretically userspace-visible, but I am not aware of
any code that it will actually break.
Fixes: 64b875f7ac ("ptrace: Capture the ptracer's creds not PT_PTRACE_CAP")
Signed-off-by: Jann Horn <jannh@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Fixes a deadlock from a previous fix to keep module loading
and function tracing text modifications from stepping on each other.
(this has a few patches to help document the issue in comments)
- Fix a crash when the snapshot buffer gets out of sync with the
main ring buffer.
- Fix a memory leak when reading the memory logs
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXRzBCBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qnDaAP9qTFBOFtgIGCT5wVP8xjQeESxh1b8R
tbaT7/U2oPpeiwEAvp1mYo5UYcc8KauBqVaLSLJVN4pv07xiZF5Qgh9C1QE=
=m2IT
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing fixes from Steven Rostedt:
"This includes three fixes:
- Fix a deadlock from a previous fix to keep module loading and
function tracing text modifications from stepping on each other
(this has a few patches to help document the issue in comments)
- Fix a crash when the snapshot buffer gets out of sync with the main
ring buffer
- Fix a memory leak when reading the memory logs"
* tag 'trace-v5.2-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace:
ftrace/x86: Anotate text_mutex split between ftrace_arch_code_modify_post_process() and ftrace_arch_code_modify_prepare()
tracing/snapshot: Resize spare buffer if size changed
tracing: Fix memory leak in tracing_err_log_open()
ftrace/x86: Add a comment to why we take text_mutex in ftrace_arch_code_modify_prepare()
ftrace/x86: Remove possible deadlock between register_kprobe() and ftrace_run_update_code()
Daniel Borkmann says:
====================
pull-request: bpf 2019-07-03
The following pull-request contains BPF updates for your *net* tree.
The main changes are:
1) Fix the interpreter to properly handle BPF_ALU32 | BPF_ARSH
on BE architectures, from Jiong.
2) Fix several bugs in the x32 BPF JIT for handling shifts by 0,
from Luke and Xi.
3) Fix NULL pointer deref in btf_type_is_resolve_source_only(),
from Stanislav.
4) Properly handle the check that forwarding is enabled on the device
in bpf_ipv6_fib_lookup() helper code, from Anton.
5) Fix UAPI bpf_prog_info fields alignment for archs that have 16 bit
alignment such as m68k, from Baruch.
6) Fix kernel hanging in unregister_netdevice loop while unregistering
device bound to XDP socket, from Ilya.
7) Properly terminate tail update in xskq_produce_flush_desc(), from Nathan.
8) Fix broken always_inline handling in test_lwt_seg6local, from Jiri.
9) Fix bpftool to use correct argument in cgroup errors, from Jakub.
10) Fix detaching dummy prog in XDP redirect sample code, from Prashant.
11) Add Jonathan to AF_XDP reviewers, from Björn.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
When calling debugfs functions, there is no need to ever check the
return value. The function can work or not, but the code logic should
never do something different based on this.
Cc: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Marek Szyprowski <m.szyprowski@samsung.com>
Cc: Robin Murphy <robin.murphy@arm.com>
Cc: iommu@lists.linux-foundation.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lore.kernel.org/r/20190612144314.GA16803@kroah.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
When equivalent state is found the current state needs to propagate precision marks.
Otherwise the verifier will prune the search incorrectly.
There is a price for correctness:
before before broken fixed
cnst spill precise precise
bpf_lb-DLB_L3.o 1923 8128 1863 1898
bpf_lb-DLB_L4.o 3077 6707 2468 2666
bpf_lb-DUNKNOWN.o 1062 1062 544 544
bpf_lxc-DDROP_ALL.o 166729 380712 22629 36823
bpf_lxc-DUNKNOWN.o 174607 440652 28805 45325
bpf_netdev.o 8407 31904 6801 7002
bpf_overlay.o 5420 23569 4754 4858
bpf_lxc_jit.o 39389 359445 50925 69631
Overall precision tracking is still very effective.
Fixes: b5dc0163d8 ("bpf: precise scalar_value tracking")
Reported-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Tested-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
free_irq() ensures that no hardware interrupt handler is executing on a
different CPU before actually releasing resources and deactivating the
interrupt completely in a domain hierarchy.
But that does not catch the case where the interrupt is on flight at the
hardware level but not yet serviced by the target CPU. That creates an
interesing race condition:
CPU 0 CPU 1 IRQ CHIP
interrupt is raised
sent to CPU1
Unable to handle
immediately
(interrupts off,
deep idle delay)
mask()
...
free()
shutdown()
synchronize_irq()
release_resources()
do_IRQ()
-> resources are not available
That might be harmless and just trigger a spurious interrupt warning, but
some interrupt chips might get into a wedged state.
Utilize the existing irq_get_irqchip_state() callback for the
synchronization in free_irq().
synchronize_hardirq() is not using this mechanism as it might actually
deadlock unter certain conditions, e.g. when called with interrupts
disabled and the target CPU is the one on which the synchronization is
invoked. synchronize_irq() uses it because that function cannot be called
from non preemtible contexts as it might sleep.
No functional change intended and according to Marc the existing GIC
implementations where the driver supports the callback should be able
to cope with that core change. Famous last words.
Fixes: 464d12309e ("x86/vector: Switch IOAPIC to global reservation mode")
Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Tested-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190628111440.279463375@linutronix.de
When interrupts are shutdown, they are immediately deactivated in the
irqdomain hierarchy. While this looks obviously correct there is a subtle
issue:
There might be an interrupt in flight when free_irq() is invoking the
shutdown. This is properly handled at the irq descriptor / primary handler
level, but the deactivation might completely disable resources which are
required to acknowledge the interrupt.
Split the shutdown code and deactivate the interrupt after synchronization
in free_irq(). Fixup all other usage sites where this is not an issue to
invoke the combined shutdown_and_deactivate() function instead.
This still might be an issue if the interrupt in flight servicing is
delayed on a remote CPU beyond the invocation of synchronize_irq(), but
that cannot be handled at that level and needs to be handled in the
synchronize_irq() context.
Fixes: f8264e3496 ("irqdomain: Introduce new interfaces to support hierarchy irqdomains")
Reported-by: Robert Hodaszi <Robert.Hodaszi@digi.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Marc Zyngier <marc.zyngier@arm.com>
Link: https://lkml.kernel.org/r/20190628111440.098196390@linutronix.de
!current->mm is not a reliable indicator for kernel threads as they might
temporarily use a user mm. Check for PF_KTHREAD instead.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1907021750100.1802@nanos.tec.linutronix.de
Christoph Hellwig says:
====================
Below is a series that cleans up the dev_pagemap interface so that it is
more easily usable, which removes the need to wrap it in hmm and thus
allowing to kill a lot of code
Changes since v3:
- pull in "mm/swap: Fix release_pages() when releasing devmap pages" and
rebase the other patches on top of that
- fold the hmm_devmem_add_resource into the DEVICE_PUBLIC memory removal
patch
- remove _vm_normal_page as it isn't needed without DEVICE_PUBLIC memory
- pick up various ACKs
Changes since v2:
- fix nvdimm kunit build
- add a new memory type for device dax
- fix a few issues in intermediate patches that didn't show up in the end
result
- incorporate feedback from Michal Hocko, including killing of
the DEVICE_PUBLIC memory type entirely
Changes since v1:
- rebase
- also switch p2pdma to the internal refcount
- add type checking for pgmap->type
- rename the migrate method to migrate_to_ram
- cleanup the altmap_valid flag
- various tidbits from the reviews
====================
Conflicts resolved by:
- Keeping Ira's version of the code in swap.c
- Using the delete for the section in hmm.rst
- Using the delete for the devmap code in hmm.c and .h
* branch 'hmm-devmem-cleanup.4': (24 commits)
mm: don't select MIGRATE_VMA_HELPER from HMM_MIRROR
mm: remove the HMM config option
mm: sort out the DEVICE_PRIVATE Kconfig mess
mm: simplify ZONE_DEVICE page private data
mm: remove hmm_devmem_add
mm: remove hmm_vma_alloc_locked_page
nouveau: use devm_memremap_pages directly
nouveau: use alloc_page_vma directly
PCI/P2PDMA: use the dev_pagemap internal refcount
device-dax: use the dev_pagemap internal refcount
memremap: provide an optional internal refcount in struct dev_pagemap
memremap: replace the altmap_valid field with a PGMAP_ALTMAP_VALID flag
memremap: remove the data field in struct dev_pagemap
memremap: add a migrate_to_ram method to struct dev_pagemap_ops
memremap: lift the devmap_enable manipulation into devm_memremap_pages
memremap: pass a struct dev_pagemap to ->kill and ->cleanup
memremap: move dev_pagemap callbacks into a separate structure
memremap: validate the pagemap type passed to devm_memremap_pages
mm: factor out a devm_request_free_mem_region helper
mm: export alloc_pages_vma
...
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl0YK7ceHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGWfcH/36ep8GZHY9H1ARV
RJJoGoMnwENoq2o4eKhH3iZgUIGPq2uonazequhePwnIsrOdFGT7AeMHWSW7W0o4
wNlNFdUrTe0bvU00m+YtDwNIqgNCnFEoUbqn9H+VhAAWpSydKvhh2mlebTFO50KN
hb9+jh59Q8tbxrQdCuNF6yJATdf4hcj1V/ZZMGgF34kx+dFY4wOooSfu/eaIxXIl
fBDKN9K4Mmw8HWJvebV+ocOMZ7Zqknt1lbjx69OxpJmgxhb2Ks7heqSZanLTBPBB
oZxOlEdNPSyOjBQUlsDC2S8VJ7g5gINZk1JcFjByzE7cIPOQ2UXE72R++wwANngm
SR054NQ=
=WlA8
-----END PGP SIGNATURE-----
Merge tag 'v5.2-rc7' into rdma.git hmm
Required for dependencies in the next patches.
Provide an internal refcounting logic if no ->ref field is provided
in the pagemap passed into devm_memremap_pages so that callers don't
have to reinvent it poorly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Add a flags field to struct dev_pagemap to replace the altmap_valid
boolean to be a little more extensible. Also add a pgmap_altmap() helper
to find the optional altmap and clean up the code using the altmap using
it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
struct dev_pagemap is always embedded into a containing structure, so
there is no need to an additional private data field.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
This replaces the hacky ->fault callback, which is currently directly
called from common code through a hmm specific data structure as an
exercise in layering violations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ralph Campbell <rcampbell@nvidia.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Just check if there is a ->page_free operation set and take care of the
static key enable, as well as the put using device managed resources.
Also check that a ->page_free is provided for the pgmaps types that
require it, and check for a valid type as well while we are at it.
Note that this also fixes the fact that hmm never called
dev_pagemap_put_ops and thus would leave the slow path enabled forever,
even after a device driver unload or disable.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Passing the actual typed structure leads to more understandable code
vs just passing the ref member.
Reported-by: Logan Gunthorpe <logang@deltatee.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
The dev_pagemap is a growing too many callbacks. Move them into a
separate ops structure so that they are not duplicated for multiple
instances, and an attacker can't easily overwrite them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Most pgmap types are only supported when certain config options are
enabled. Check for a type that is valid for the current configuration
before setting up the pagemap. For this the usage of the 0 type for
device dax gets replaced with an explicit MEMORY_DEVICE_DEVDAX type.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Tested-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
Keep the physical address allocation that hmm_add_device does with the
rest of the resource code, and allow future reuse of it without the hmm
wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
-----BEGIN PGP SIGNATURE-----
iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAl0Os1seHHRvcnZhbGRz
QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGtx4H/j6i482XzcGFKTBm
A7mBoQpy+kLtoUov4EtBAR62OuwI8rsahW9di37QKndPoQrczWaKBmr3De6LCdPe
v3pl3O6wBbvH5ru+qBPFX9PdNbDvimEChh7LHxmMxNQq3M+AjZAZVJyfpoiFnx35
Fbge+LZaH/k8HMwZmkMr5t9Mpkip715qKg2o9Bua6dkH0AqlcpLlC8d9a+HIVw/z
aAsyGSU8jRwhoAOJsE9bJf0acQ/pZSqmFp0rDKqeFTSDMsbDRKLGq/dgv4nW0RiW
s7xqsjb/rdcvirRj3rv9+lcTVkOtEqwk0PVdL9WOf7g4iYrb3SOIZh8ZyViaDSeH
VTS5zps=
=huBY
-----END PGP SIGNATURE-----
Merge tag 'v5.2-rc6' into for-5.3/block
Merge 5.2-rc6 into for-5.3/block, so we get the same page merge leak
fix. Otherwise we end up having conflicts with future patches between
for-5.3/block and master that touch this area. In particular, it makes
the bio_full() fix hard to backport to stable.
* tag 'v5.2-rc6': (482 commits)
Linux 5.2-rc6
Revert "iommu/vt-d: Fix lock inversion between iommu->lock and device_domain_lock"
Bluetooth: Fix regression with minimum encryption key size alignment
tcp: refine memory limit test in tcp_fragment()
x86/vdso: Prevent segfaults due to hoisted vclock reads
SUNRPC: Fix a credential refcount leak
Revert "SUNRPC: Declare RPC timers as TIMER_DEFERRABLE"
net :sunrpc :clnt :Fix xps refcount imbalance on the error path
NFS4: Only set creation opendata if O_CREAT
ARM: 8867/1: vdso: pass --be8 to linker if necessary
KVM: nVMX: reorganize initial steps of vmx_set_nested_state
KVM: PPC: Book3S HV: Invalidate ERAT when flushing guest TLB entries
habanalabs: use u64_to_user_ptr() for reading user pointers
nfsd: replace Jeff by Chuck as nfsd co-maintainer
inet: clear num_timeout reqsk_alloc()
PCI/P2PDMA: Ignore root complex whitelist when an IOMMU is present
net: mvpp2: debugfs: Add pmap to fs dump
ipv6: Default fib6_type to RTN_UNICAST when not set
net: hns3: Fix inconsistent indenting
net/af_iucv: always register net_device notifier
...
During soft reboot(kexec_file_load) boot command line
arguments are not measured.
Call ima hook ima_kexec_cmdline to measure the boot command line
arguments into IMA measurement list.
- call ima_kexec_cmdline from kexec_file_load.
- move the call ima_add_kexec_buffer after the cmdline
args have been measured.
Signed-off-by: Prakhar Srivastava <prsriva02@gmail.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
Pull SMP fixes from Thomas Gleixner:
"Two small changes for the cpu hotplug code:
- Prevent out of bounds access which actually might crash the machine
caused by a missing bounds check in the fail injection code
- Warn about unsupported migitation mode command line arguments to
make people aware that they typoed the paramater. Not necessarily a
fix but quite some people tripped over that"
* 'smp-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
cpu/hotplug: Fix out-of-bounds read when setting fail state
cpu/speculation: Warn on unsupported mitigations= parameter
Pull perf fixes from Ingo Molnar:
"Various fixes, most of them related to bugs perf fuzzing found in the
x86 code"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/regs: Use PERF_REG_EXTENDED_MASK
perf/x86: Remove pmu->pebs_no_xmm_regs
perf/x86: Clean up PEBS_XMM_REGS
perf/x86/regs: Check reserved bits
perf/x86: Disable extended registers for non-supported PMUs
perf/ioctl: Add check for the sample_period value
perf/core: Fix perf_sample_regs_user() mm check
Avoid skipping bus-level PCI power management during system
resume for PCIe ports left in D0 during the preceding suspend
transition on platforms where the power states of those ports
can change out of the PCI layer's control.
-----BEGIN PGP SIGNATURE-----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=eGQi
-----END PGP SIGNATURE-----
Merge tag 'pm-5.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management fix from Rafael Wysocki:
"Avoid skipping bus-level PCI power management during system resume for
PCIe ports left in D0 during the preceding suspend transition on
platforms where the power states of those ports can change out of the
PCI layer's control"
* tag 'pm-5.2-rc7' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm:
PCI: PM: Avoid skipping bus-level PM on platforms without ACPI
Commit 5eed6f1dff ("fork,memcg: fix crash in free_thread_stack on
memcg charge fail") corrected two instances, but there was a third
instance of this bug.
Without setting tsk->stack, if memcg_charge_kernel_stack fails, it'll
execute free_thread_stack() on a dangling pointer.
Enterprise kernels are compiled with VMAP_STACK=y so this isn't
critical, but custom VMAP_STACK=n builds should have some performance
advantage, with the drawback of risking to fail fork because compaction
didn't succeed. So as long as VMAP_STACK=n is a supported option it's
worth fixing it upstream.
Link: http://lkml.kernel.org/r/20190619011450.28048-1-aarcange@redhat.com
Fixes: 9b6f7e163c ("mm: rework memcg kernel stack accounting")
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Rik van Riel <riel@surriel.com>
Acked-by: Roman Gushchin <guro@fb.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This is the minimal fix for stable, I'll send cleanups later.
Commit 854a6ed568 ("signal: Add restore_user_sigmask()") introduced
the visible change which breaks user-space: a signal temporary unblocked
by set_user_sigmask() can be delivered even if the caller returns
success or timeout.
Change restore_user_sigmask() to accept the additional "interrupted"
argument which should be used instead of signal_pending() check, and
update the callers.
Eric said:
: For clarity. I don't think this is required by posix, or fundamentally to
: remove the races in select. It is what linux has always done and we have
: applications who care so I agree this fix is needed.
:
: Further in any case where the semantic change that this patch rolls back
: (aka where allowing a signal to be delivered and the select like call to
: complete) would be advantage we can do as well if not better by using
: signalfd.
:
: Michael is there any chance we can get this guarantee of the linux
: implementation of pselect and friends clearly documented. The guarantee
: that if the system call completes successfully we are guaranteed that no
: signal that is unblocked by using sigmask will be delivered?
Link: http://lkml.kernel.org/r/20190604134117.GA29963@redhat.com
Fixes: 854a6ed568 ("signal: Add restore_user_sigmask()")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Reported-by: Eric Wong <e@80x24.org>
Tested-by: Eric Wong <e@80x24.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Deepa Dinamani <deepa.kernel@gmail.com>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jason Baron <jbaron@akamai.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Al Viro <viro@ZenIV.linux.org.uk>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: <stable@vger.kernel.org> [5.0+]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
We don't currently allow lookups into a devmap from eBPF, because the map
lookup returns a pointer directly to the dev->ifindex, which shouldn't be
modifiable from eBPF.
However, being able to do lookups in devmaps is useful to know (e.g.)
whether forwarding to a specific interface is enabled. Currently, programs
work around this by keeping a shadow map of another type which indicates
whether a map index is valid.
Since we now have a flag to make maps read-only from the eBPF side, we can
simply lift the lookup restriction if we make sure this flag is always set.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The socket map uses a linked list instead of a bitmap to keep track of
which entries to flush. Do the same for devmap and cpumap, as this means we
don't have to care about the map index when enqueueing things into the
map (and so we can cache the map lookup).
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Acked-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Add a helper in list.h for the non-standard way of clearing a list that is
used in xskmap. This makes it easier to reuse it in the other map types,
and also makes sure this usage is not forgotten in any list refactorings in
the future.
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
The commit 9f255b632b ("module: Fix livepatch/ftrace module text
permissions race") causes a possible deadlock between register_kprobe()
and ftrace_run_update_code() when ftrace is using stop_machine().
The existing dependency chain (in reverse order) is:
-> #1 (text_mutex){+.+.}:
validate_chain.isra.21+0xb32/0xd70
__lock_acquire+0x4b8/0x928
lock_acquire+0x102/0x230
__mutex_lock+0x88/0x908
mutex_lock_nested+0x32/0x40
register_kprobe+0x254/0x658
init_kprobes+0x11a/0x168
do_one_initcall+0x70/0x318
kernel_init_freeable+0x456/0x508
kernel_init+0x22/0x150
ret_from_fork+0x30/0x34
kernel_thread_starter+0x0/0xc
-> #0 (cpu_hotplug_lock.rw_sem){++++}:
check_prev_add+0x90c/0xde0
validate_chain.isra.21+0xb32/0xd70
__lock_acquire+0x4b8/0x928
lock_acquire+0x102/0x230
cpus_read_lock+0x62/0xd0
stop_machine+0x2e/0x60
arch_ftrace_update_code+0x2e/0x40
ftrace_run_update_code+0x40/0xa0
ftrace_startup+0xb2/0x168
register_ftrace_function+0x64/0x88
klp_patch_object+0x1a2/0x290
klp_enable_patch+0x554/0x980
do_one_initcall+0x70/0x318
do_init_module+0x6e/0x250
load_module+0x1782/0x1990
__s390x_sys_finit_module+0xaa/0xf0
system_call+0xd8/0x2d0
Possible unsafe locking scenario:
CPU0 CPU1
---- ----
lock(text_mutex);
lock(cpu_hotplug_lock.rw_sem);
lock(text_mutex);
lock(cpu_hotplug_lock.rw_sem);
It is similar problem that has been solved by the commit 2d1e38f566
("kprobes: Cure hotplug lock ordering issues"). Many locks are involved.
To be on the safe side, text_mutex must become a low level lock taken
after cpu_hotplug_lock.rw_sem.
This can't be achieved easily with the current ftrace design.
For example, arm calls set_all_modules_text_rw() already in
ftrace_arch_code_modify_prepare(), see arch/arm/kernel/ftrace.c.
This functions is called:
+ outside stop_machine() from ftrace_run_update_code()
+ without stop_machine() from ftrace_module_enable()
Fortunately, the problematic fix is needed only on x86_64. It is
the only architecture that calls set_all_modules_text_rw()
in ftrace path and supports livepatching at the same time.
Therefore it is enough to move text_mutex handling from the generic
kernel/trace/ftrace.c into arch/x86/kernel/ftrace.c:
ftrace_arch_code_modify_prepare()
ftrace_arch_code_modify_post_process()
This patch basically reverts the ftrace part of the problematic
commit 9f255b632b ("module: Fix livepatch/ftrace module
text permissions race"). And provides x86_64 specific-fix.
Some refactoring of the ftrace code will be needed when livepatching
is implemented for arm or nds32. These architectures call
set_all_modules_text_rw() and use stop_machine() at the same time.
Link: http://lkml.kernel.org/r/20190627081334.12793-1-pmladek@suse.com
Fixes: 9f255b632b ("module: Fix livepatch/ftrace module text permissions race")
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Reported-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Miroslav Benes <mbenes@suse.cz>
Reviewed-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
[
As reviewed by Miroslav Benes <mbenes@suse.cz>, removed return value of
ftrace_run_update_code() as it is a void function.
]
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This adds the pidfd_open() syscall. It allows a caller to retrieve pollable
pidfds for a process which did not get created via CLONE_PIDFD, i.e. for a
process that is created via traditional fork()/clone() calls that is only
referenced by a PID:
int pidfd = pidfd_open(1234, 0);
ret = pidfd_send_signal(pidfd, SIGSTOP, NULL, 0);
With the introduction of pidfds through CLONE_PIDFD it is possible to
created pidfds at process creation time.
However, a lot of processes get created with traditional PID-based calls
such as fork() or clone() (without CLONE_PIDFD). For these processes a
caller can currently not create a pollable pidfd. This is a problem for
Android's low memory killer (LMK) and service managers such as systemd.
Both are examples of tools that want to make use of pidfds to get reliable
notification of process exit for non-parents (pidfd polling) and race-free
signal sending (pidfd_send_signal()). They intend to switch to this API for
process supervision/management as soon as possible. Having no way to get
pollable pidfds from PID-only processes is one of the biggest blockers for
them in adopting this api. With pidfd_open() making it possible to retrieve
pidfds for PID-based processes we enable them to adopt this api.
In line with Arnd's recent changes to consolidate syscall numbers across
architectures, I have added the pidfd_open() syscall to all architectures
at the same time.
Signed-off-by: Christian Brauner <christian@brauner.io>
Reviewed-by: David Howells <dhowells@redhat.com>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jann Horn <jannh@google.com>
Cc: Andy Lutomirsky <luto@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-api@vger.kernel.org
This patch adds polling support to pidfd.
Android low memory killer (LMK) needs to know when a process dies once
it is sent the kill signal. It does so by checking for the existence of
/proc/pid which is both racy and slow. For example, if a PID is reused
between when LMK sends a kill signal and checks for existence of the
PID, since the wrong PID is now possibly checked for existence.
Using the polling support, LMK will be able to get notified when a process
exists in race-free and fast way, and allows the LMK to do other things
(such as by polling on other fds) while awaiting the process being killed
to die.
For notification to polling processes, we follow the same existing
mechanism in the kernel used when the parent of the task group is to be
notified of a child's death (do_notify_parent). This is precisely when the
tasks waiting on a poll of pidfd are also awakened in this patch.
We have decided to include the waitqueue in struct pid for the following
reasons:
1. The wait queue has to survive for the lifetime of the poll. Including
it in task_struct would not be option in this case because the task can
be reaped and destroyed before the poll returns.
2. By including the struct pid for the waitqueue means that during
de_thread(), the new thread group leader automatically gets the new
waitqueue/pid even though its task_struct is different.
Appropriate test cases are added in the second patch to provide coverage of
all the cases the patch is handling.
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Daniel Colascione <dancol@google.com>
Cc: Jann Horn <jannh@google.com>
Cc: Tim Murray <timmurray@google.com>
Cc: Jonathan Kowalski <bl0pbl33p@gmail.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: David Howells <dhowells@redhat.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: kernel-team@android.com
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Co-developed-by: Daniel Colascione <dancol@google.com>
Signed-off-by: Daniel Colascione <dancol@google.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Christian Brauner <christian@brauner.io>
Use zeroing allocator instead of using allocator
followed with memset with 0
Signed-off-by: Fuqian Huang <huangfq.daxian@gmail.com>
Acked-by: Pavel Machek <pavel@ucw.cz>
[ rjw: Subject ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
The new route handling in ip_mc_finish_output() from 'net' overlapped
with the new support for returning congestion notifications from BPF
programs.
In order to handle this I had to take the dev_loopback_xmit() calls
out of the switch statement.
The aquantia driver conflicts were simple overlapping changes.
Signed-off-by: David S. Miller <davem@davemloft.net>
Implement new BPF_PROG_TYPE_CGROUP_SOCKOPT program type and
BPF_CGROUP_{G,S}ETSOCKOPT cgroup hooks.
BPF_CGROUP_SETSOCKOPT can modify user setsockopt arguments before
passing them down to the kernel or bypass kernel completely.
BPF_CGROUP_GETSOCKOPT can can inspect/modify getsockopt arguments that
kernel returns.
Both hooks reuse existing PTR_TO_PACKET{,_END} infrastructure.
The buffer memory is pre-allocated (because I don't think there is
a precedent for working with __user memory from bpf). This might be
slow to do for each {s,g}etsockopt call, that's why I've added
__cgroup_bpf_prog_array_is_empty that exits early if there is nothing
attached to a cgroup. Note, however, that there is a race between
__cgroup_bpf_prog_array_is_empty and BPF_PROG_RUN_ARRAY where cgroup
program layout might have changed; this should not be a problem
because in general there is a race between multiple calls to
{s,g}etsocktop and user adding/removing bpf progs from a cgroup.
The return code of the BPF program is handled as follows:
* 0: EPERM
* 1: success, continue with next BPF program in the cgroup chain
v9:
* allow overwriting setsockopt arguments (Alexei Starovoitov):
* use set_fs (same as kernel_setsockopt)
* buffer is always kzalloc'd (no small on-stack buffer)
v8:
* use s32 for optlen (Andrii Nakryiko)
v7:
* return only 0 or 1 (Alexei Starovoitov)
* always run all progs (Alexei Starovoitov)
* use optval=0 as kernel bypass in setsockopt (Alexei Starovoitov)
(decided to use optval=-1 instead, optval=0 might be a valid input)
* call getsockopt hook after kernel handlers (Alexei Starovoitov)
v6:
* rework cgroup chaining; stop as soon as bpf program returns
0 or 2; see patch with the documentation for the details
* drop Andrii's and Martin's Acked-by (not sure they are comfortable
with the new state of things)
v5:
* skip copy_to_user() and put_user() when ret == 0 (Martin Lau)
v4:
* don't export bpf_sk_fullsock helper (Martin Lau)
* size != sizeof(__u64) for uapi pointers (Martin Lau)
* offsetof instead of bpf_ctx_range when checking ctx access (Martin Lau)
v3:
* typos in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY comments (Andrii Nakryiko)
* reverse christmas tree in BPF_PROG_CGROUP_SOCKOPT_RUN_ARRAY (Andrii
Nakryiko)
* use __bpf_md_ptr instead of __u32 for optval{,_end} (Martin Lau)
* use BPF_FIELD_SIZEOF() for consistency (Martin Lau)
* new CG_SOCKOPT_ACCESS macro to wrap repeated parts
v2:
* moved bpf_sockopt_kern fields around to remove a hole (Martin Lau)
* aligned bpf_sockopt_kern->buf to 8 bytes (Martin Lau)
* bpf_prog_array_is_empty instead of bpf_prog_array_length (Martin Lau)
* added [0,2] return code check to verifier (Martin Lau)
* dropped unused buf[64] from the stack (Martin Lau)
* use PTR_TO_SOCKET for bpf_sockopt->sk (Martin Lau)
* dropped bpf_target_off from ctx rewrites (Martin Lau)
* use return code for kernel bypass (Martin Lau & Andrii Nakryiko)
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: Martin Lau <kafai@fb.com>
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
That gets rid of this warning:
./kernel/time/hrtimer.c:1119: WARNING: Block quote ends without a blank line; unexpected unindent.
and displays nicely both at the source code and at the produced
documentation.
Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Linux Doc Mailing List <linux-doc@vger.kernel.org>
Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Link: https://lkml.kernel.org/r/74ddad7dac331b4e5ce4a90e15c8a49e3a16d2ac.1561372382.git.mchehab+samsung@kernel.org
All callers use GFP_KERNEL. No point in having that argument.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
None of those functions have any users outside of workqueue.c. Confine
them.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Tejun Heo <tj@kernel.org>
Since commit 4bfc0bb2c6 ("bpf: decouple the lifetime of cgroup_bpf
from cgroup itself"), cgroup_bpf release occurs asynchronously
(from a worker context), and before the release of the cgroup itself.
This introduced a previously non-existing race between the release
and update paths. E.g. if a leaf's cgroup_bpf is released and a new
bpf program is attached to the one of ancestor cgroups at the same
time. The race may result in double-free and other memory corruptions.
To fix the problem, let's protect the body of cgroup_bpf_release()
with cgroup_mutex, as it was effectively previously, when all this
code was called from the cgroup release path with cgroup mutex held.
Also let's skip cgroups, which have no chances to invoke a bpf
program, on the update path. If the cgroup bpf refcnt reached 0,
it means that the cgroup is offline (no attached processes), and
there are no associated sockets left. It means there is no point
in updating effective progs array! And it can lead to a leak,
if it happens after the release. So, let's skip such cgroups.
Big thanks for Tejun Heo for discovering and debugging of this problem!
Fixes: 4bfc0bb2c6 ("bpf: decouple the lifetime of cgroup_bpf from cgroup itself")
Reported-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Roman Gushchin <guro@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
anon_inode_getfd() should be used *ONLY* in situations when we are
guaranteed to be past the last failure point (including copying the
descriptor number to userland, at that). And ksys_close() should
not be used for cleanups at all.
anon_inode_getfile() is there for all nontrivial cases like that.
Just use that...
Fixes: b3e5838252 ("clone: add CLONE_PIDFD")
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Reviewed-by: Jann Horn <jannh@google.com>
Signed-off-by: Christian Brauner <christian@brauner.io>
Setting invalid value to /sys/devices/system/cpu/cpuX/hotplug/fail
can control `struct cpuhp_step *sp` address, results in the following
global-out-of-bounds read.
Reproducer:
# echo -2 > /sys/devices/system/cpu/cpu0/hotplug/fail
KASAN report:
BUG: KASAN: global-out-of-bounds in write_cpuhp_fail+0x2cd/0x2e0
Read of size 8 at addr ffffffff89734438 by task bash/1941
CPU: 0 PID: 1941 Comm: bash Not tainted 5.2.0-rc6+ #31
Call Trace:
write_cpuhp_fail+0x2cd/0x2e0
dev_attr_store+0x58/0x80
sysfs_kf_write+0x13d/0x1a0
kernfs_fop_write+0x2bc/0x460
vfs_write+0x1e1/0x560
ksys_write+0x126/0x250
do_syscall_64+0xc1/0x390
entry_SYSCALL_64_after_hwframe+0x49/0xbe
RIP: 0033:0x7f05e4f4c970
The buggy address belongs to the variable:
cpu_hotplug_lock+0x98/0xa0
Memory state around the buggy address:
ffffffff89734300: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
ffffffff89734380: fa fa fa fa 00 00 00 00 00 00 00 00 00 00 00 00
>ffffffff89734400: 00 00 00 00 fa fa fa fa 00 00 00 00 fa fa fa fa
^
ffffffff89734480: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
ffffffff89734500: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
Add a sanity check for the value written from user space.
Fixes: 1db49484f2 ("smp/hotplug: Hotplug state fail injection")
Signed-off-by: Eiichi Tsukata <devel@etsukata.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: peterz@infradead.org
Link: https://lkml.kernel.org/r/20190627024732.31672-1-devel@etsukata.com
... since we immediately follow that with check that it *is* an
opened perf file, with O_PATH ones ending with with the same
-EBADF we'd get for descriptor that isn't opened at all.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
There are platforms that do not call pm_set_suspend_via_firmware(),
so pm_suspend_via_firmware() returns 'false' on them, but the power
states of PCI devices (PCIe ports in particular) are changed as a
result of powering down core platform components during system-wide
suspend. Thus the pm_suspend_via_firmware() checks in
pci_pm_suspend_noirq() and pci_pm_resume_noirq() introduced by
commit 3e26c5feed ("PCI: PM: Skip devices in D0 for suspend-to-
idle") are not sufficient to determine that devices left in D0
during suspend will remain in D0 during resume and so the bus-level
power management can be skipped for them.
For this reason, introduce a new global suspend flag,
PM_SUSPEND_FLAG_NO_PLATFORM, set it for suspend-to-idle only
and replace the pm_suspend_via_firmware() checks mentioned above
with checks against this flag.
Fixes: 3e26c5feed ("PCI: PM: Skip devices in D0 for suspend-to-idle")
Reported-by: Jon Hunter <jonathanh@nvidia.com>
Tested-by: Jon Hunter <jonathanh@nvidia.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Move the user and user-session keyrings to the user_namespace struct rather
than pinning them from the user_struct struct. This prevents these
keyrings from propagating across user-namespaces boundaries with regard to
the KEY_SPEC_* flags, thereby making them more useful in a containerised
environment.
The issue is that a single user_struct may be represent UIDs in several
different namespaces.
The way the patch does this is by attaching a 'register keyring' in each
user_namespace and then sticking the user and user-session keyrings into
that. It can then be searched to retrieve them.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Jann Horn <jannh@google.com>
Keyring names are held in a single global list that any process can pick
from by means of keyctl_join_session_keyring (provided the keyring grants
Search permission). This isn't very container friendly, however.
Make the following changes:
(1) Make default session, process and thread keyring names begin with a
'.' instead of '_'.
(2) Keyrings whose names begin with a '.' aren't added to the list. Such
keyrings are system specials.
(3) Replace the global list with per-user_namespace lists. A keyring adds
its name to the list for the user_namespace that it is currently in.
(4) When a user_namespace is deleted, it just removes itself from the
keyring name list.
The global keyring_name_lock is retained for accessing the name lists.
This allows (4) to work.
This can be tested by:
# keyctl newring foo @s
995906392
# unshare -U
$ keyctl show
...
995906392 --alswrv 65534 65534 \_ keyring: foo
...
$ keyctl session foo
Joined session keyring: 935622349
As can be seen, a new session keyring was created.
The capability bit KEYCTL_CAPS1_NS_KEYRING_NAME is set if the kernel is
employing this feature.
Signed-off-by: David Howells <dhowells@redhat.com>
cc: Eric W. Biederman <ebiederm@xmission.com>
If CONFIG_ARCH_HAS_STRICT_MODULE_RWX is not defined,
we need stub for module_enable_nx() and module_enable_x().
If CONFIG_ARCH_HAS_STRICT_MODULE_RWX is defined, but
CONFIG_STRICT_MODULE_RWX is disabled, we need stub for
module_enable_nx.
Move frob_text() outside of the CONFIG_STRICT_MODULE_RWX,
because it is needed anyway.
Fixes: 2eef1399a8 ("modules: fix BUG when load module with rodata=n")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
Currently, if the user specifies an unsupported mitigation strategy on the
kernel command line, it will be ignored silently. The code will fall back
to the default strategy, possibly leaving the system more vulnerable than
expected.
This may happen due to e.g. a simple typo, or, for a stable kernel release,
because not all mitigation strategies have been backported.
Inform the user by printing a message.
Fixes: 98af845294 ("cpu/speculation: Add 'mitigations=' cmdline option")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jiri Kosina <jkosina@suse.cz>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Ben Hutchings <ben@decadent.org.uk>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20190516070935.22546-1-geert@linux-m68k.org
Yauheni reported the following code do not work correctly on BE arches:
ALU_ARSH_X:
DST = (u64) (u32) ((*(s32 *) &DST) >> SRC);
CONT;
ALU_ARSH_K:
DST = (u64) (u32) ((*(s32 *) &DST) >> IMM);
CONT;
and are causing failure of test_verifier test 'arsh32 on imm 2' on BE
arches.
The code is taking address and interpreting memory directly, so is not
endianness neutral. We should instead perform standard C type casting on
the variable. A u64 to s32 conversion will drop the high 32-bit and reserve
the low 32-bit as signed integer, this is all we want.
Fixes: 2dc6b100f9 ("bpf: interpreter support BPF_ALU | BPF_ARSH")
Reported-by: Yauheni Kaliuta <yauheni.kaliuta@redhat.com>
Reviewed-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Quentin Monnet <quentin.monnet@netronome.com>
Signed-off-by: Jiong Wang <jiong.wang@netronome.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
With CONFIG_MODULES=n, the following compiler warning occurs:
/data/users/yhs/work/net-next/kernel/trace/bpf_trace.c:605:13: warning:
‘do_bpf_send_signal’ defined but not used [-Wunused-function]
static void do_bpf_send_signal(struct irq_work *entry)
The __init function send_signal_irq_work_init(), which calls
do_bpf_send_signal(), is defined under CONFIG_MODULES. Hence,
when CONFIG_MODULES=n, nobody calls static function do_bpf_send_signal(),
hence the warning.
The init function send_signal_irq_work_init() should work without
CONFIG_MODULES. Moving it out of CONFIG_MODULES
code section fixed the compiler warning, and also make bpf_send_signal()
helper work without CONFIG_MODULES.
Fixes: 8b401f9ed2 ("bpf: implement bpf_send_signal() helper")
Reported-By: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Yonghong Song <yhs@fb.com>
Acked-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
DMA_ATTR_NO_KERNEL_MAPPING is generally implemented by allocating
normal cacheable pages or CMA memory, and then returning the page
pointer as the opaque handle. Lift that code from the xtensa and
generic dma remapping implementations into the generic dma-direct
code so that we don't even call arch_dma_alloc for these allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Only call into arch_dma_alloc if we require an uncached mapping,
and remove the parisc code manually doing normal cached
DMA_ATTR_NON_CONSISTENT allocations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Helge Deller <deller@gmx.de> # parisc
