To add recursive read locks into the dependency graph, we need to store
the types of dependencies for the BFS later. There are four types of
dependencies:
* Exclusive -> Non-recursive dependencies: EN
e.g. write_lock(prev) held and try to acquire write_lock(next)
or non-recursive read_lock(next), which can be represented as
"prev -(EN)-> next"
* Shared -> Non-recursive dependencies: SN
e.g. read_lock(prev) held and try to acquire write_lock(next) or
non-recursive read_lock(next), which can be represented as
"prev -(SN)-> next"
* Exclusive -> Recursive dependencies: ER
e.g. write_lock(prev) held and try to acquire recursive
read_lock(next), which can be represented as "prev -(ER)-> next"
* Shared -> Recursive dependencies: SR
e.g. read_lock(prev) held and try to acquire recursive
read_lock(next), which can be represented as "prev -(SR)-> next"
So we use 4 bits for the presence of each type in lock_list::dep. Helper
functions and macros are also introduced to convert a pair of locks into
lock_list::dep bit and maintain the addition of different types of
dependencies.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-7-boqun.feng@gmail.com
lock_list::distance is always not greater than MAX_LOCK_DEPTH (which
is 48 right now), so a u16 will fit. This patch reduces the size of
lock_list::distance to save space, so that we can introduce other fields
to help detect recursive read lock deadlocks without increasing the size
of lock_list structure.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-6-boqun.feng@gmail.com
Currently, __bfs() will do a breadth-first search in the dependency
graph and visit each lock class in the graph exactly once, so for
example, in the following graph:
A ---------> B
| ^
| |
+----------> C
a __bfs() call starts at A, will visit B through dependency A -> B and
visit C through dependency A -> C and that's it, IOW, __bfs() will not
visit dependency C -> B.
This is OK for now, as we only have strong dependencies in the
dependency graph, so whenever there is a traverse path from A to B in
__bfs(), it means A has strong dependencies to B (IOW, B depends on A
strongly). So no need to visit all dependencies in the graph.
However, as we are going to add recursive-read lock into the dependency
graph, as a result, not all the paths mean strong dependencies, in the
same example above, dependency A -> B may be a weak dependency and
traverse A -> C -> B may be a strong dependency path. And with the old
way of __bfs() (i.e. visiting every lock class exactly once), we will
miss the strong dependency path, which will result into failing to find
a deadlock. To cure this for the future, we need to find a way for
__bfs() to visit each dependency, rather than each class, exactly once
in the search until we find a match.
The solution is simple:
We used to mark lock_class::lockdep_dependency_gen_id to indicate a
class has been visited in __bfs(), now we change the semantics a little
bit: we now mark lock_class::lockdep_dependency_gen_id to indicate _all
the dependencies_ in its lock_{after,before} have been visited in the
__bfs() (note we only take one direction in a __bfs() search). In this
way, every dependency is guaranteed to be visited until we find a match.
Note: the checks in mark_lock_accessed() and lock_accessed() are
removed, because after this modification, we may call these two
functions on @source_entry of __bfs(), which may not be the entry in
"list_entries"
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-5-boqun.feng@gmail.com
__bfs() could return four magic numbers:
1: search succeeds, but none match.
0: search succeeds, find one match.
-1: search fails because of the cq is full.
-2: search fails because a invalid node is found.
This patch cleans things up by using a enum type for the return value
of __bfs() and its friends, this improves the code readability of the
code, and further, could help if we want to extend the BFS.
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-4-boqun.feng@gmail.com
On the archs using QUEUED_RWLOCKS, read_lock() is not always a recursive
read lock, actually it's only recursive if in_interrupt() is true. So
change the annotation accordingly to catch more deadlocks.
Note we used to treat read_lock() as pure recursive read locks in
lib/locking-seftest.c, and this is useful, especially for the lockdep
development selftest, so we keep this via a variable to force switching
lock annotation for read_lock().
Signed-off-by: Boqun Feng <boqun.feng@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200807074238.1632519-2-boqun.feng@gmail.com
SD_DEGENERATE_GROUPS_MASK is only useful for sched/topology.c, but still
gets defined for anyone who imports topology.h, leading to a flurry of
unused variable warnings.
Move it out of the header and place it next to the SD degeneration
functions in sched/topology.c.
Fixes: 4ee4ea443a ("sched/topology: Introduce SD metaflag for flags needing > 1 groups")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.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/20200825133216.9163-2-valentin.schneider@arm.com
Defining an array in a header imported all over the place clearly is a daft
idea, that still didn't stop me from doing it.
Leave a declaration of sd_flag_debug in topology.h and move its definition
to sched/debug.c.
Fixes: b6e862f386 ("sched/topology: Define and assign sched_domain flag metadata")
Reported-by: Andy Shevchenko <andriy.shevchenko@linux.intel.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/20200825133216.9163-1-valentin.schneider@arm.com
sched_submit_work() is considered to be a hot path. The preempt_disable()
instruction is a compiler barrier and forces the compiler to load
task_struct::flags for the second comparison.
By using a local variable, the compiler can load the value once and keep it in
a register for the second comparison.
Verified on x86-64 with gcc-10.
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200819200025.lqvmyefqnbok5i4f@linutronix.de
The code in reweight_entity() can be simplified.
For a sched entity on the rq, the entity accounting can be replaced by
cfs_rq instantaneous load updates currently called from within the
entity accounting.
Even though an entity on the rq can't represent a task in
reweight_entity() (a task is always dequeued before calling this
function) and so the numa task accounting and the rq->cfs_tasks list
management of the entity accounting are never called, the redundant
cfs_rq->nr_running decrement/increment will be avoided.
Signed-off-by: Jiang Biao <benbjiang@tencent.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Reviewed-by: Vincent Guittot <vincent.guittot@linaro.org>
Link: https://lkml.kernel.org/r/20200811113209.34057-1-benbjiang@tencent.com
In find_energy_efficient_cpu() 'cpu_cap' could be less that 'util'.
It might be because of RT, DL (so higher sched class than CFS), irq or
thermal pressure signal, which reduce the capacity value.
In such situation the result of 'cpu_cap - util' might be negative but
stored in the unsigned long. Then it might be compared with other unsigned
long when uclamp_rq_util_with() reduced the 'util' such that is passes the
fits_capacity() check.
Prevent this situation and make the arithmetic more safe.
Fixes: 1d42509e47 ("sched/fair: Make EAS wakeup placement consider uclamp restrictions")
Signed-off-by: Lukasz Luba <lukasz.luba@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Link: https://lkml.kernel.org/r/20200810083004.26420-1-lukasz.luba@arm.com
SMT siblings share caches, so cache hotness should be irrelevant for
cross-sibling migration.
Signed-off-by: Josh Don <joshdon@google.com>
Proposed-by: Venkatesh Pallipadi <venki@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200804193413.510651-1-joshdon@google.com
The lockdep tracepoints are under the lockdep recursion counter, this
has a bunch of nasty side effects:
- TRACE_IRQFLAGS doesn't work across the entire tracepoint
- RCU-lockdep doesn't see the tracepoints either, hiding numerous
"suspicious RCU usage" warnings.
Pull the trace_lock_*() tracepoints completely out from under the
lockdep recursion handling and completely rely on the trace level
recusion handling -- also, tracing *SHOULD* not be taking locks in any
case.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.782688941@infradead.org
Remove trace_cpu_idle() from the arch_cpu_idle() implementations and
put it in the generic code, right before disabling RCU. Gets rid of
more trace_*_rcuidle() users.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.428433395@infradead.org
Lots of things take locks, due to a wee bug, rcu_lockdep didn't notice
that the locking tracepoints were using RCU.
Push rcu_idle_{enter,exit}() as deep as possible into the idle paths,
this also resolves a lot of _rcuidle()/RCU_NONIDLE() usage.
Specifically, sched_clock_idle_wakeup_event() will use ktime which
will use seqlocks which will tickle lockdep, and
stop_critical_timings() uses lock.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Link: https://lkml.kernel.org/r/20200821085348.310943801@infradead.org
Sven reported that commit a21ee6055c ("lockdep: Change
hardirq{s_enabled,_context} to per-cpu variables") caused trouble on
s390 because their this_cpu_*() primitives disable preemption which
then lands back tracing.
On the one hand, per-cpu ops should use preempt_*able_notrace() and
raw_local_irq_*(), on the other hand, we can trivialy use raw_cpu_*()
ops for this.
Fixes: a21ee6055c ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables")
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Tested-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200821085348.192346882@infradead.org
Adding d_path helper function that returns full path for
given 'struct path' object, which needs to be the kernel
BTF 'path' object. The path is returned in buffer provided
'buf' of size 'sz' and is zero terminated.
bpf_d_path(&file->f_path, buf, size);
The helper calls directly d_path function, so there's only
limited set of function it can be called from. Adding just
very modest set for the start.
Updating also bpf.h tools uapi header and adding 'path' to
bpf_helpers_doc.py script.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: KP Singh <kpsingh@google.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-11-jolsa@kernel.org
Adding support to define sorted set of BTF ID values.
Following defines sorted set of BTF ID values:
BTF_SET_START(btf_allowlist_d_path)
BTF_ID(func, vfs_truncate)
BTF_ID(func, vfs_fallocate)
BTF_ID(func, dentry_open)
BTF_ID(func, vfs_getattr)
BTF_ID(func, filp_close)
BTF_SET_END(btf_allowlist_d_path)
It defines following 'struct btf_id_set' variable to access
values and count:
struct btf_id_set btf_allowlist_d_path;
Adding 'allowed' callback to struct bpf_func_proto, to allow
verifier the check on allowed callers.
Adding btf_id_set_contains function, which will be used by
allowed callbacks to verify the caller's BTF ID value is
within allowed set.
Also removing extra '\' in __BTF_ID_LIST macro.
Added BTF_SET_START_GLOBAL macro for global sets.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-10-jolsa@kernel.org
Adding btf_struct_ids_match function to check if given address provided
by BTF object + offset is also address of another nested BTF object.
This allows to pass an argument to helper, which is defined via parent
BTF object + offset, like for bpf_d_path (added in following changes):
SEC("fentry/filp_close")
int BPF_PROG(prog_close, struct file *file, void *id)
{
...
ret = bpf_d_path(&file->f_path, ...
The first bpf_d_path argument is hold by verifier as BTF file object
plus offset of f_path member.
The btf_struct_ids_match function will walk the struct file object and
check if there's nested struct path object on the given offset.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-9-jolsa@kernel.org
Adding btf_struct_walk function that walks through the
struct type + given offset and returns following values:
enum bpf_struct_walk_result {
/* < 0 error */
WALK_SCALAR = 0,
WALK_PTR,
WALK_STRUCT,
};
WALK_SCALAR - when SCALAR_VALUE is found
WALK_PTR - when pointer value is found, its ID is stored
in 'next_btf_id' output param
WALK_STRUCT - when nested struct object is found, its ID is stored
in 'next_btf_id' output param
It will be used in following patches to get all nested
struct objects for given type and offset.
The btf_struct_access now calls btf_struct_walk function,
as long as it gets nested structs as return value.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-8-jolsa@kernel.org
Andrii suggested we can simply jump to again label
instead of making recursion call.
Suggested-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-7-jolsa@kernel.org
Adding type_id pointer as argument to __btf_resolve_size
to return also BTF ID of the resolved type. It will be
used in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-6-jolsa@kernel.org
If the resolved type is array, make btf_resolve_size return also
ID of the elem type. It will be needed in following changes.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-5-jolsa@kernel.org
Moving btf_resolve_size into __btf_resolve_size and
keeping btf_resolve_size public with just first 3
arguments, because the rest of the arguments are not
used by outside callers.
Following changes are adding more arguments, which
are not useful to outside callers. They will be added
to the __btf_resolve_size function.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200825192124.710397-4-jolsa@kernel.org
The CC_CAN_LINK checks that the host compiler can link, but bpf_preload
relies on libbpf which in turn needs libelf to be present during linking.
allmodconfig runs in odd setups with cross compilers and missing host
libraries like libelf. Instead of extending kconfig with every possible
library that bpf_preload might need disallow building BPF_PRELOAD in
such build-only configurations.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Adds support for both bpf_{sk, inode}_storage_{get, delete} to be used
in LSM programs. These helpers are not used for tracing programs
(currently) as their usage is tied to the life-cycle of the object and
should only be used where the owning object won't be freed (when the
owning object is passed as an argument to the LSM hook). Thus, they
are safer to use in LSM hooks than tracing. Usage of local storage in
tracing programs will probably follow a per function based whitelist
approach.
Since the UAPI helper signature for bpf_sk_storage expect a bpf_sock,
it, leads to a compilation warning for LSM programs, it's also updated
to accept a void * pointer instead.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200825182919.1118197-7-kpsingh@chromium.org
Similar to bpf_local_storage for sockets, add local storage for inodes.
The life-cycle of storage is managed with the life-cycle of the inode.
i.e. the storage is destroyed along with the owning inode.
The BPF LSM allocates an __rcu pointer to the bpf_local_storage in the
security blob which are now stackable and can co-exist with other LSMs.
Signed-off-by: KP Singh <kpsingh@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200825182919.1118197-6-kpsingh@chromium.org
Replace a comma between expression statements by a semicolon.
Signed-off-by: Xu Wang <vulab@iscas.ac.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Link: https://lore.kernel.org/r/20200818062651.21680-1-vulab@iscas.ac.cn
Commit f2e10bff16 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link")
added link query for raw_tp. One of fields in link_info is to
fill a user buffer with tp_name. The Scurrent checking only
declares "ulen && !ubuf" as invalid. So "!ulen && ubuf" will be
valid. Later on, we do "copy_to_user(ubuf, tp_name, ulen - 1)" which
may overwrite user memory incorrectly.
This patch fixed the problem by disallowing "!ulen && ubuf" case as well.
Fixes: f2e10bff16 ("bpf: Add support for BPF_OBJ_GET_INFO_BY_FD for bpf_link")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200821191054.714731-1-yhs@fb.com
This commit adds an rcutorture.leakpointer module parameter that
intentionally leaks an RCU-protected pointer out of the RCU read-side
critical section and checks to see if the corresponding grace period
has elapsed, emitting a WARN_ON_ONCE() if so. This module parameter can
be used to test facilities like CONFIG_RCU_STRICT_GRACE_PERIOD that end
grace periods quickly.
While in the area, also document rcutorture.irqreader, which was
previously left out.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, registering and unregistering the OOM notifier is done
right before and after the test, respectively. This will not work
well for multi-threaded tests, so this commit hoists this registering
and unregistering up into the rcu_torture_fwd_prog_init() and
rcu_torture_fwd_prog_cleanup() functions.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently in the unlikely event that buf fails to be allocated it
is dereferenced a few times. Use the errexit flag to determine if
buf should be written to to avoid the null pointer dereferences.
Addresses-Coverity: ("Dereference after null check")
Fixes: f518f154ec ("refperf: Dynamically allocate experiment-summary output buffer")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The current rcutorture forward-progress code assumes that it is the
only cause of out-of-memory (OOM) events. For script-based rcutorture
testing, this assumption is in fact correct. However, testing based
on modprobe/rmmod might well encounter external OOM events, which could
happen at any time.
This commit therefore properly synchronizes the interaction between
rcutorture's forward-progress testing and its OOM notifier by adding a
global mutex.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The conversion of rcu_fwds to dynamic allocation failed to actually
allocate the required structure. This commit therefore allocates it,
frees it, and updates rcu_fwds accordingly. While in the area, it
abstracts the cleanup actions into rcu_torture_fwd_prog_cleanup().
Fixes: 5155be9994 ("rcutorture: Dynamically allocate rcu_fwds structure")
Reported-by: kernel test robot <rong.a.chen@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The sparse tool complains as follows:
kernel/locking/locktorture.c:569:6: warning:
symbol 'torture_percpu_rwsem_init' was not declared. Should it be static?
And this function is not used outside of locktorture.c,
so this commit marks it static.
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds code to print the grace-period number at the start
of the test along with both the grace-period number and the number of
elapsed grace periods at the end of the test. Note that variants of
RCU)without the notion of a grace-period number (for example, Tiny RCU)
just print zeroes.
[ paulmck: Adjust commit log. ]
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
KCSAN is now in mainline, so this commit removes the stubs for the
data_race(), ASSERT_EXCLUSIVE_WRITER(), and ASSERT_EXCLUSIVE_ACCESS()
macros.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The "cpu" parameter to rcu_report_qs_rdp() is not used, with rdp->cpu
being used instead. Furtheremore, every call to rcu_report_qs_rdp()
invokes it on rdp->cpu. This commit therefore removes this unused "cpu"
parameter and converts a check of rdp->cpu against smp_processor_id()
to a WARN_ON_ONCE().
Reported-by: Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The CONFIG_PREEMPT=n instance of rcu_read_unlock is even more
aggressively than that of CONFIG_PREEMPT=y in deferring reporting
quiescent states to the RCU core. This is just what is wanted in normal
use because it reduces overhead, but the resulting delay is not what
is wanted for kernels built with CONFIG_RCU_STRICT_GRACE_PERIOD=y.
This commit therefore adds an rcu_read_unlock_strict() function that
checks for exceptional conditions, and reports the newly started
quiescent state if it is safe to do so, also doing a spin-delay if
requested via rcutree.rcu_unlock_delay. This commit also adds a call
to rcu_read_unlock_strict() from the CONFIG_PREEMPT=n instance of
__rcu_read_unlock().
[ paulmck: Fixed bug located by kernel test robot <lkp@intel.com> ]
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
A kernel built with CONFIG_RCU_STRICT_GRACE_PERIOD=y needs a quiescent
state to appear very shortly after a CPU has noticed a new grace period.
Placing an RCU reader immediately after this point is ineffective because
this normally happens in softirq context, which acts as a big RCU reader.
This commit therefore introduces a new per-CPU work_struct, which is
used at the end of rcu_core() processing to schedule an RCU read-side
critical section from within a clean environment.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The goal of this series is to increase the probability of tools like
KASAN detecting that an RCU-protected pointer was used outside of its
RCU read-side critical section. Thus far, the approach has been to make
grace periods and callback processing happen faster. Another approach
is to delay the pointer leaker. This commit therefore allows a delay
to be applied to exit from RCU read-side critical sections.
This slowdown is specified by a new rcutree.rcu_unlock_delay kernel boot
parameter that specifies this delay in microseconds, defaulting to zero.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, each CPU discovers the end of a given grace period on its
own time, which is again good for efficiency but bad for fast grace
periods, given that it is things like kfree() within the RCU callbacks
that will cause trouble for pointers leaked from RCU read-side critical
sections. This commit therefore uses on_each_cpu() to IPI each CPU
after grace-period cleanup in order to inform each CPU of the end of
the old grace period in a timely manner, but only in kernels build with
CONFIG_RCU_STRICT_GRACE_PERIOD=y.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, each CPU discovers the beginning of a given grace period
on its own time, which is again good for efficiency but bad for fast
grace periods. This commit therefore uses on_each_cpu() to IPI each
CPU after grace-period initialization in order to inform each CPU of
the new grace period in a timely manner, but only in kernels build with
CONFIG_RCU_STRICT_GRACE_PERIOD=y.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
A given CPU normally notes a new grace period during one RCU_SOFTIRQ,
but avoids reporting the corresponding quiescent state until some later
RCU_SOFTIRQ. This leisurly approach improves efficiency by increasing
the number of update requests served by each grace period, but is not
what is needed for kernels built with CONFIG_RCU_STRICT_GRACE_PERIOD=y.
This commit therefore adds a new rcu_strict_gp_check_qs() function
which, in CONFIG_RCU_STRICT_GRACE_PERIOD=y kernels, simply enters and
immediately exist an RCU read-side critical section. If the CPU is
in a quiescent state, the rcu_read_unlock() will attempt to report an
immediate quiescent state. This rcu_strict_gp_check_qs() function is
invoked from note_gp_changes(), so that a CPU just noticing a new grace
period might immediately report a quiescent state for that grace period.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_preempt_deferred_qs_irqrestore() function is invoked at
the end of an RCU read-side critical section (for example, directly
from rcu_read_unlock()) and, if .need_qs is set, invokes rcu_qs() to
report the new quiescent state. This works, except that rcu_qs() only
updates per-CPU state, leaving reporting of the actual quiescent state
to a later call to rcu_report_qs_rdp(), for example from within a later
RCU_SOFTIRQ instance. Although this approach is exactly what you want if
you are more concerned about efficiency than about short grace periods,
in CONFIG_RCU_STRICT_GRACE_PERIOD=y kernels, short grace periods are
the name of the game.
This commit therefore makes rcu_preempt_deferred_qs_irqrestore() directly
invoke rcu_report_qs_rdp() in CONFIG_RCU_STRICT_GRACE_PERIOD=y, thus
shortening grace periods.
Historical note: To the best of my knowledge, causing rcu_read_unlock()
to directly report a quiescent state first appeared in Jim Houston's
and Joe Korty's JRCU. This is the second instance of a Linux-kernel RCU
feature being inspired by JRCU, the first being RCU callback offloading
(as in the RCU_NOCB_CPU Kconfig option).
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The ->rcu_read_unlock_special.b.need_qs field in the task_struct
structure indicates that the RCU core needs a quiscent state from the
corresponding task. The __rcu_read_unlock() function checks this (via
an eventual call to rcu_preempt_deferred_qs_irqrestore()), and if set
reports a quiscent state immediately upon exit from the outermost RCU
read-side critical section.
Currently, this flag is only set when the scheduling-clock interrupt
decides that the current RCU grace period is too old, as in about
one full second too old. But if the kernel has been built with
CONFIG_RCU_STRICT_GRACE_PERIOD=y, we clearly do not want to wait that
long. This commit therefore sets the .need_qs field immediately at the
start of the RCU read-side critical section from within __rcu_read_lock()
in order to unconditionally enlist help from __rcu_read_unlock().
But note the additional check for rcu_state.gp_kthread, which prevents
attempts to awaken RCU's grace-period kthread during early boot before
there is a scheduler. Leaving off this check results in early boot hangs.
So early that there is no console output. Thus, this additional check
fails until such time as RCU's grace-period kthread has been created,
avoiding these empty-console hangs.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The value of DEFAULT_RCU_BLIMIT is normally set to 10, the idea being to
avoid needless response-time degradation due to RCU callback invocation.
However, when CONFIG_RCU_STRICT_GRACE_PERIOD=y it is better to avoid
throttling callback execution in order to better detect pointer
leaks from RCU read-side critical sections. This commit therefore
sets the value of DEFAULT_RCU_BLIMIT to 1000 in kernels built with
CONFIG_RCU_STRICT_GRACE_PERIOD=y.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
If there are idle CPUs, RCU's grace-period kthread will wait several
jiffies before even thinking about polling them. This promotes
efficiency, which is normally a good thing, but when the kernel
has been built with CONFIG_RCU_STRICT_GRACE_PERIOD=y, we care more
about short grace periods. This commit therefore restricts the
default jiffies_till_first_fqs value to zero in kernels built with
CONFIG_RCU_STRICT_GRACE_PERIOD=y, which causes RCU's grace-period kthread
to poll for idle CPUs immediately after starting a grace period.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Because strict RCU grace periods will complete more quickly, they will
experience greater lock contention on each leaf rcu_node structure's
->lock. This commit therefore reduces the leaf fanout in order to reduce
this lock contention.
Note that this also has the effect of reducing the number of CPUs
supported to 16 in the case of CONFIG_RCU_FANOUT_LEAF=2 or 81 in the
case of CONFIG_RCU_FANOUT_LEAF=3. However, greater numbers of CPUs are
probably a bad idea when using CONFIG_RCU_STRICT_GRACE_PERIOD=y. Those
wishing to live dangerously are free to edit their kernel/rcu/Kconfig
files accordingly.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
People running automated tests have asked for a way to make RCU minimize
grace-period duration in order to increase the probability of KASAN
detecting a pointer being improperly leaked from an RCU read-side critical
section, for example, like this:
rcu_read_lock();
p = rcu_dereference(gp);
do_something_with(p); // OK
rcu_read_unlock();
do_something_else_with(p); // BUG!!!
The rcupdate.rcu_expedited boot parameter is a start in this direction,
given that it makes calls to synchronize_rcu() instead invoke the faster
(and more wasteful) synchronize_rcu_expedited(). However, this does
nothing to shorten RCU grace periods that are instead initiated by
call_rcu(), and RCU pointer-leak bugs can involve call_rcu() just as
surely as they can synchronize_rcu().
This commit therefore adds a RCU_STRICT_GRACE_PERIOD Kconfig option
that will be used to shorten normal (non-expedited) RCU grace periods.
This commit also dumps out a message when this option is in effect.
Later commits will actually shorten grace periods.
Reported-by Jann Horn <jannh@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit further avoids conflation of rcuperf with the kernel's perf
feature by renaming kernel/rcu/rcuperf.c to kernel/rcu/rcuscale.c, and
also by similarly renaming the functions and variables inside this file.
This has the side effect of changing the names of the kernel boot
parameters, so kernel-parameters.txt and ver_functions.sh are also
updated. The rcutorture --torture type was also updated from rcuperf
to rcuscale.
[ paulmck: Fix bugs located by Stephen Rothwell. ]
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Although the test loop does randomly delay, which would provide quiescent
states and so forth, it is possible for there to be a series of long
smp_call_function*() handler runtimes with no delays, which results in
softlockup and RCU CPU stall warning messages. This commit therefore
inserts a cond_resched() into the main test loop.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
On uniprocessor systems, smp_call_function() does nothing. This commit
therefore avoids complaining about the lack of handler accesses in the
single-CPU case where there is no handler.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, CPU-hotplug operations might result in all but two
of (say) 100 CPUs being offline, which in turn might result in
false-positive diagnostics due to overload. This commit therefore
causes scftorture_invoker() kthreads for offline CPUs to loop blocking
for 200 milliseconds at a time, thus continuously adjusting the number
of threads to match the number of online CPUs.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds a "default" case to the switch statement in
scftorture_invoke_one() which contains a WARN_ON_ONCE() and an assignment
to ->scfc_out to suppress knock-on warnings. These knock-on warnings
could otherwise cause the user to think that there was a memory-ordering
problem in smp_call_function() instead of a bug in scftorture.c itself.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The sparse tool complains as follows
kernel/scftorture.c:124:1: warning:
symbol '__pcpu_scope_scf_torture_rand' was not declared. Should it be static?
And this per-CPU variable is not used outside of scftorture.c,
so this commit marks it static.
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Detecting smp_call_function() memory misordering requires close timing,
so it is necessary to have the checks immediately before and after
the call to the smp_call_function*() function under test. This commit
therefore inserts barrier() calls to prevent the compiler from optimizing
memory-misordering detection down into the zone of extreme improbability.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit prints error counts on the statistics line and also adds a
"!!!" if any of the counters are non-zero. Allocation failures are
(somewhat) forgiven, but all other errors result in a "FAILURE" print
at the end of the test.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit hoists much of the initialization of the scf_check
structure out of the switch statement, thus saving a few lines of code.
The initialization of the ->scfc_in field remains in each leg of the
switch statement in order to more heavily stress memory ordering.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit moves checking of the ->scfc_out field and the freeing of
the scf_check structure down below the end of switch statement, thus
saving a few lines of code.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds checks for memory misordering across calls to and
returns from smp_call_function() in the case where the caller waits.
Misordering results in a splat.
Note that in contrast to smp_call_function_single(), this code does not
test memory ordering into the handler in the no-wait case because none
of the handlers would be able to free the scf_check structure without
introducing heavy synchronization to work out which was last.
[ paulmck: s/GFP_KERNEL/GFP_ATOMIC/ per kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds checks for memory misordering across calls to and
returns from smp_call_function_many() in the case where the caller waits.
Misordering results in a splat.
Note that in contrast to smp_call_function_single(), this code does not
test memory ordering into the handler in the no-wait case because none
of the handlers would be able to free the scf_check structure without
introducing heavy synchronization to work out which was last.
[ paulmck: s/GFP_KERNEL/GFP_ATOMIC/ per kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds checks for memory misordering across calls to
smp_call_function_single() and also across returns in the case where
the caller waits. Misordering results in a splat.
[ paulmck: s/GFP_KERNEL/GFP_ATOMIC/ per kernel test robot feedback. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit summarizes the per-thread statistics, providing counts of
the number of single, many, and all calls, both no-wait and wait, and,
for the single case, the number where the target CPU was offline.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, can_stop_idle_tick() prints "NOHZ: local_softirq_pending HH"
(where "HH" is the hexadecimal softirq vector number) when one or more
non-RCU softirq handlers are still enabled when checking to stop the
scheduler-tick interrupt. This message is not as enlightening as one
might hope, so this commit changes it to "NOHZ tick-stop error: Non-RCU
local softirq work is pending, handler #HH".
Reported-by: Andy Lutomirski <luto@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit uses the scftorture.weight* kernel parameters to randomly
chooses between smp_call_function_single(), smp_call_function_many(),
and smp_call_function(). For each variant, it also randomly chooses
whether to invoke it synchronously (wait=1) or asynchronously (wait=0).
The percentage weighting for each option are dumped to the console log
(search for "scf_sel_dump").
This accumulates statistics, which a later commit will dump out at the
end of the run.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds an smp_call_function() torture test that repeatedly
invokes this function and complains if things go badly awry.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The x86/entry work removed all uses of __rcu_is_watching(), therefore
this commit removes it entirely.
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: <x86@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The RCU grace-period kthread's force-quiescent state (FQS) loop should
never see an offline CPU that has not yet reported a quiescent state.
After all, the offline CPU should have reported a quiescent state
during the CPU-offline process, or, failing that, by rcu_gp_init()
if it ran concurrently with either the CPU going offline or the last
task on a leaf rcu_node structure exiting its RCU read-side critical
section while all CPUs corresponding to that structure are offline.
The FQS loop should therefore complain if it does see an offline CPU
that has not yet reported a quiescent state.
And it does, but only once the grace period has been in force for a
full second. This commit therefore makes this warning more aggressive,
so that it will trigger as soon as the condition makes its appearance.
Light testing with TREE03 and hotplug shows no warnings. This commit
also converts the warning to WARN_ON_ONCE() in order to stave off possible
log spam.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Since at least v4.19, the FQS loop no longer reports quiescent states
for offline CPUs except in emergency situations.
This commit therefore fixes the comment in rcu_gp_init() to match the
current code.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit increases RCU's ability to defend itself by emitting a warning
if one of the nocb CB kthreads invokes the GP kthread's wait function.
This warning augments a similar check that is carried out at the end
of rcutorture testing and when RCU CPU stall warnings are emitted.
The problem with those checks is that the miscreants have long since
departed and disposed of any and all evidence.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
When the rcu_cpu_started per-CPU variable was added by commit
f64c6013a2 ("rcu/x86: Provide early rcu_cpu_starting() callback"),
there were multiple sets of per-CPU rcu_data structures. Therefore, the
rcu_cpu_started flag was added as a separate per-CPU variable. But now
there is only one set of per-CPU rcu_data structures, so this commit
moves rcu_cpu_started to a new ->cpu_started field in that structure.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Given that sysfs can change the value of rcu_cpu_stall_ftrace_dump at any
time, this commit adds a READ_ONCE() to the accesses to that variable.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Given that sysfs can change the value of rcu_kick_kthreads at any time,
this commit adds a READ_ONCE() to the sole access to that variable.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Given that sysfs can change the value of rcu_resched_ns at any time,
this commit adds a READ_ONCE() to the sole access to that variable.
While in the area, this commit also adds bounds checking, clamping the
value to at least a millisecond, but no longer than a second.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Given that sysfs can change the value of rcu_divisor at any time, this
commit adds a READ_ONCE to the sole access to that variable. While in
the area, this commit also adds bounds checking, clamping the value to
a shift that makes sense for a signed long.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_data structure's ->nocb_timer field is used to defer wakeups of
the corresponding no-CBs CPU's grace-period kthread ("rcuog*"), and that
structure's ->nocb_defer_wakeup field is used to track such deferral.
This means that the show_rcu_nocb_state() printing an error when those
fields are set for a CPU not corresponding to a no-CBs grace-period
kthread is erroneous.
This commit therefore switches the check from ->nocb_timer to
->nocb_bypass_timer and removes the check of ->nocb_defer_wakeup.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Originally, the call to rcu_preempt_blocked_readers_cgp() from
force_qs_rnp() had to be conditioned on CONFIG_PREEMPT_RCU=y, as in
commit a77da14ce9 ("rcu: Yet another fix for preemption and CPU
hotplug"). However, there is now a CONFIG_PREEMPT_RCU=n definition of
rcu_preempt_blocked_readers_cgp() that unconditionally returns zero, so
invoking it is now safe. In addition, the CONFIG_PREEMPT_RCU=n definition
of rcu_initiate_boost() simply releases the rcu_node structure's ->lock,
which is what happens when the "if" condition evaluates to false.
This commit therefore drops the IS_ENABLED(CONFIG_PREEMPT_RCU) check,
so that rcu_initiate_boost() is called only in CONFIG_PREEMPT_RCU=y
kernels when there are readers blocking the current grace period.
This does not change the behavior, but reduces code-reader confusion by
eliminating non-CONFIG_PREEMPT_RCU=y calls to rcu_initiate_boost().
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
On callback overload, it is necessary to quickly detect idle CPUs,
and rcu_gp_fqs_check_wake() checks for this condition. Unfortunately,
the code following the call to this function does not repeat this check,
which means that in reality no actual quiescent-state forcing, instead
only a couple of quick and pointless wakeups at the beginning of the
grace period.
This commit therefore adds a check for the RCU_GP_FLAG_OVLD flag in
the post-wakeup "if" statement in rcu_gp_fqs_loop().
Fixes: 1fca4d12f4 ("rcu: Expedite first two FQS scans under callback-overload conditions")
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Neeraj Upadhyay <neeraju@codeaurora.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
A message of the form "rcu: !!! lDTs ." can be tracked down, but
doing so is not trivial. This commit therefore eases this process by
adding text so that this error message now reads as follows:
"rcu: nocb GP activity on CB-only CPU!!! lDTs ."
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
During acceleration of CB, the rsp's gp_seq is rcu_seq_snap'd. This is
the value used for acceleration - it is the value of gp_seq at which it
is safe the execute all callbacks in the callback list.
The rdp's gp_seq is not very useful for this scenario. Make
rcu_grace_period report the gp_seq_req instead as it allows one to
reason about how the acceleration works.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit moves the initialization of the CONFIG_PREEMPT=n version of
the rcu_exp_handler() function's rdp and rnp local variables into their
respective declarations to save a couple lines of code.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
KCSAN is now in mainline, so this commit removes the stubs for the
data_race(), ASSERT_EXCLUSIVE_WRITER(), and ASSERT_EXCLUSIVE_ACCESS()
macros.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
KCSAN is now in mainline, so this commit removes the stubs for the
data_race(), ASSERT_EXCLUSIVE_WRITER(), and ASSERT_EXCLUSIVE_ACCESS()
macros.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
KCSAN is now in mainline, so this commit removes the stubs for the
data_race(), ASSERT_EXCLUSIVE_WRITER(), and ASSERT_EXCLUSIVE_ACCESS()
macros.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Remove kcsan_counter_inc/dec() functions, as they perform no other
logic, and are no longer needed.
This avoids several calls in kcsan_setup_watchpoint() and
kcsan_found_watchpoint(), as well as lets the compiler warn us about
potential out-of-bounds accesses as the array's size is known at all
usage sites at compile-time.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Use the same pr_fmt throughout for consistency. [ The only exception is
report.c, where the format must be kept precisely as-is. ]
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Show a message in the kernel log if KCSAN was enabled early.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Remove the debugfs test command, as it is no longer needed now that we
have the KUnit+Torture based kcsan-test module. This is to avoid
confusion around how KCSAN should be tested, as only the kcsan-test
module is maintained.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Simplify checking prefixes and length calculation of constant strings.
For the former, the kernel provides str_has_prefix(), and the latter we
should just use strlen("..") because GCC and Clang have optimizations
that optimize these into constants.
No functional change intended.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Simplify counter ID to name mapping by using an array with designated
inits. This way, we can turn a run-time BUG() into a compile-time static
assertion failure if a counter name is missing.
No functional change intended.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Changes kcsan-test module to support checking reports that include
compound instrumentation. Since we should not fail the test if this
support is unavailable, we have to add a config variable that the test
can use to decide what to check for.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add missing CONFIG_KCSAN_IGNORE_ATOMICS checks for the builtin atomics
instrumentation.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
For compound instrumentation and assert accesses, skew the watchpoint
delay to be longer if randomized. This is useful to improve race
detection for such accesses.
For compound accesses we should increase the delay as we've aggregated
both read and write instrumentation. By giving up 1 call into the
runtime, we're less likely to set up a watchpoint and thus less likely
to detect a race. We can balance this by increasing the watchpoint
delay.
For assert accesses, we know these are of increased interest, and we
wish to increase our chances of detecting races for such checks.
Note that, kcsan_udelay_{task,interrupt} define the upper bound delays.
When randomized, delays are uniformly distributed between [0, delay].
Skewing the delay does not break this promise as long as the defined
upper bounds are still adhered to. The current skew results in delays
uniformly distributed between [delay/2, delay].
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add support for compounded read-write instrumentation if supported by
the compiler. Adds the necessary instrumentation functions, and a new
type which is used to generate a more descriptive report.
Furthermore, such compounded memory access instrumentation is excluded
from the "assume aligned writes up to word size are atomic" rule,
because we cannot assume that the compiler emits code that is atomic for
compound ops.
LLVM/Clang added support for the feature in:
785d41a261
The new instrumentation is emitted for sets of memory accesses in the
same basic block to the same address with at least one read appearing
before a write. These typically result from compound operations such as
++, --, +=, -=, |=, &=, etc. but also equivalent forms such as "var =
var + 1". Where the compiler determines that it is equivalent to emit a
call to a single __tsan_read_write instead of separate __tsan_read and
__tsan_write, we can then benefit from improved performance and better
reporting for such access patterns.
The new reports now show that the ops are both reads and writes, for
example:
read-write to 0xffffffff90548a38 of 8 bytes by task 143 on cpu 3:
test_kernel_rmw_array+0x45/0xa0
access_thread+0x71/0xb0
kthread+0x21e/0x240
ret_from_fork+0x22/0x30
read-write to 0xffffffff90548a38 of 8 bytes by task 144 on cpu 2:
test_kernel_rmw_array+0x45/0xa0
access_thread+0x71/0xb0
kthread+0x21e/0x240
ret_from_fork+0x22/0x30
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Adds test case to kcsan-test module, to test atomic builtin
instrumentation works.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Some architectures (currently e.g. s390 partially) implement atomics
using the compiler's atomic builtins (__atomic_*, __sync_*). To support
enabling KCSAN on such architectures in future, or support experimental
use of these builtins, implement support for them.
We should also avoid breaking KCSAN kernels due to use (accidental or
otherwise) of atomic builtins in drivers, as has happened in the past:
https://lkml.kernel.org/r/5231d2c0-41d9-6721-e15f-a7eedf3ce69e@infradead.org
The instrumentation is subtly different from regular reads/writes: TSAN
instrumentation replaces the use of atomic builtins with a call into the
runtime, and the runtime's job is to also execute the desired atomic
operation. We rely on the __atomic_* compiler builtins, available with
all KCSAN-supported compilers, to implement each TSAN atomic
instrumentation function.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
version messed up the reload of the syscall number from pt_regs after
ptrace and seccomp which breaks syscall number rewriting.
-----BEGIN PGP SIGNATURE-----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=2OhI
-----END PGP SIGNATURE-----
Merge tag 'core-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull entry fix from Thomas Gleixner:
"A single bug fix for the common entry code.
The transcription of the x86 version messed up the reload of the
syscall number from pt_regs after ptrace and seccomp which breaks
syscall number rewriting"
* tag 'core-urgent-2020-08-23' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
core/entry: Respect syscall number rewrites
Pull networking fixes from David Miller:
"Nothing earth shattering here, lots of small fixes (f.e. missing RCU
protection, bad ref counting, missing memset(), etc.) all over the
place:
1) Use get_file_rcu() in task_file iterator, from Yonghong Song.
2) There are two ways to set remote source MAC addresses in macvlan
driver, but only one of which validates things properly. Fix this.
From Alvin Šipraga.
3) Missing of_node_put() in gianfar probing, from Sumera
Priyadarsini.
4) Preserve device wanted feature bits across multiple netlink
ethtool requests, from Maxim Mikityanskiy.
5) Fix rcu_sched stall in task and task_file bpf iterators, from
Yonghong Song.
6) Avoid reset after device destroy in ena driver, from Shay
Agroskin.
7) Missing memset() in netlink policy export reallocation path, from
Johannes Berg.
8) Fix info leak in __smc_diag_dump(), from Peilin Ye.
9) Decapsulate ECN properly for ipv6 in ipv4 tunnels, from Mark
Tomlinson.
10) Fix number of data stream negotiation in SCTP, from David Laight.
11) Fix double free in connection tracker action module, from Alaa
Hleihel.
12) Don't allow empty NHA_GROUP attributes, from Nikolay Aleksandrov"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (46 commits)
net: nexthop: don't allow empty NHA_GROUP
bpf: Fix two typos in uapi/linux/bpf.h
net: dsa: b53: check for timeout
tipc: call rcu_read_lock() in tipc_aead_encrypt_done()
net/sched: act_ct: Fix skb double-free in tcf_ct_handle_fragments() error flow
net: sctp: Fix negotiation of the number of data streams.
dt-bindings: net: renesas, ether: Improve schema validation
gre6: Fix reception with IP6_TNL_F_RCV_DSCP_COPY
hv_netvsc: Fix the queue_mapping in netvsc_vf_xmit()
hv_netvsc: Remove "unlikely" from netvsc_select_queue
bpf: selftests: global_funcs: Check err_str before strstr
bpf: xdp: Fix XDP mode when no mode flags specified
selftests/bpf: Remove test_align leftovers
tools/resolve_btfids: Fix sections with wrong alignment
net/smc: Prevent kernel-infoleak in __smc_diag_dump()
sfc: fix build warnings on 32-bit
net: phy: mscc: Fix a couple of spelling mistakes "spcified" -> "specified"
libbpf: Fix map index used in error message
net: gemini: Fix missing free_netdev() in error path of gemini_ethernet_port_probe()
net: atlantic: Use readx_poll_timeout() for large timeout
...
printk wants to store various timestamps (MONOTONIC, REALTIME, BOOTTIME) to
make correlation of dmesg from several systems easier.
Provide an interface to retrieve all three timestamps in one go.
There are some caveats:
1) Boot time and late sleep time injection
Boot time is a racy access on 32bit systems if the sleep time injection
happens late during resume and not in timekeeping_resume(). That could be
avoided by expanding struct tk_read_base with boot offset for 32bit and
adding more overhead to the update. As this is a hard to observe once per
resume event which can be filtered with reasonable effort using the
accurate mono/real timestamps, it's probably not worth the trouble.
Aside of that it might be possible on 32 and 64 bit to observe the
following when the sleep time injection happens late:
CPU 0 CPU 1
timekeeping_resume()
ktime_get_fast_timestamps()
mono, real = __ktime_get_real_fast()
inject_sleep_time()
update boot offset
boot = mono + bootoffset;
That means that boot time already has the sleep time adjustment, but
real time does not. On the next readout both are in sync again.
Preventing this for 64bit is not really feasible without destroying the
careful cache layout of the timekeeper because the sequence count and
struct tk_read_base would then need two cache lines instead of one.
2) Suspend/resume timestamps
Access to the time keeper clock source is disabled accross the innermost
steps of suspend/resume. The accessors still work, but the timestamps
are frozen until time keeping is resumed which happens very early.
For regular suspend/resume there is no observable difference vs. sched
clock, but it might affect some of the nasty low level debug printks.
OTOH, access to sched clock is not guaranteed accross suspend/resume on
all systems either so it depends on the hardware in use.
If that turns out to be a real problem then this could be mitigated by
using sched clock in a similar way as during early boot. But it's not as
trivial as on early boot because it needs some careful protection
against the clock monotonic timestamp jumping backwards on resume.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200814115512.159981360@linutronix.de
During early boot the NMI safe timekeeper returns 0 until the first
clocksource becomes available.
This prevents it from being used for printk or other facilities which today
use sched clock. sched clock can be available way before timekeeping is
initialized.
The obvious workaround for this is to utilize the early sched clock in the
default dummy clock read function until a clocksource becomes available.
After switching to the clocksource clock MONOTONIC and BOOTTIME will not
jump because the timekeeping_init() bases clock MONOTONIC on sched clock
and the offset between clock MONOTONIC and BOOTTIME is zero during boot.
Clock REALTIME cannot provide useful timestamps during early boot up to
the point where a persistent clock becomes available, which is either in
timekeeping_init() or later when the RTC driver which might depend on I2C
or other subsystems is initialized.
There is a minor difference to sched_clock() vs. suspend/resume. As the
timekeeper clock source might not be accessible during suspend, after
timekeeping_suspend() timestamps freeze up to the point where
timekeeping_resume() is invoked. OTOH this is true for some sched clock
implementations as well.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200814115512.041422402@linutronix.de
Allow calling bpf_map_update_elem on sockmap and sockhash from a BPF
context. The synchronization required for this is a bit fiddly: we
need to prevent the socket from changing its state while we add it
to the sockmap, since we rely on getting a callback via
sk_prot->unhash. However, we can't just lock_sock like in
sock_map_sk_acquire because that might sleep. So instead we disable
softirq processing and use bh_lock_sock to prevent further
modification.
Yet, this is still not enough. BPF can be called in contexts where
the current CPU might have locked a socket. If the BPF can get
a hold of such a socket, inserting it into a sockmap would lead to
a deadlock. One straight forward example are sock_ops programs that
have ctx->sk, but the same problem exists for kprobes, etc.
We deal with this by allowing sockmap updates only from known safe
contexts. Improper usage is rejected by the verifier.
I've audited the enabled contexts to make sure they can't run in
a locked context. It's possible that CGROUP_SKB and others are
safe as well, but the auditing here is much more difficult. In
any case, we can extend the safe contexts when the need arises.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200821102948.21918-6-lmb@cloudflare.com
The verifier assumes that map values are simple blobs of memory, and
therefore treats ARG_PTR_TO_MAP_VALUE, etc. as such. However, there are
map types where this isn't true. For example, sockmap and sockhash store
sockets. In general this isn't a big problem: we can just
write helpers that explicitly requests PTR_TO_SOCKET instead of
ARG_PTR_TO_MAP_VALUE.
The one exception are the standard map helpers like map_update_elem,
map_lookup_elem, etc. Here it would be nice we could overload the
function prototype for different kinds of maps. Unfortunately, this
isn't entirely straight forward:
We only know the type of the map once we have resolved meta->map_ptr
in check_func_arg. This means we can't swap out the prototype
in check_helper_call until we're half way through the function.
Instead, modify check_func_arg to treat ARG_PTR_TO_MAP_VALUE to
mean "the native type for the map" instead of "pointer to memory"
for sockmap and sockhash. This means we don't have to modify the
function prototype at all
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200821102948.21918-5-lmb@cloudflare.com
Don't go via map->ops to call sock_map_update_elem, since we know
what function to call in bpf_map_update_value. Since we currently
don't allow calling map_update_elem from BPF context, we can remove
ops->map_update_elem and rename the function to sock_map_update_elem_sys.
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200821102948.21918-4-lmb@cloudflare.com
For bpf_map_elem and bpf_sk_local_storage bpf iterators,
additional map_id should be shown for fdinfo and
userspace query. For example, the following is for
a bpf_map_elem iterator.
$ cat /proc/1753/fdinfo/9
pos: 0
flags: 02000000
mnt_id: 14
link_type: iter
link_id: 34
prog_tag: 104be6d3fe45e6aa
prog_id: 173
target_name: bpf_map_elem
map_id: 127
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200821184419.574240-1-yhs@fb.com
This patch implemented bpf_link callback functions
show_fdinfo and fill_link_info to support link_query
interface.
The general interface for show_fdinfo and fill_link_info
will print/fill the target_name. Each targets can
register show_fdinfo and fill_link_info callbacks
to print/fill more target specific information.
For example, the below is a fdinfo result for a bpf
task iterator.
$ cat /proc/1749/fdinfo/7
pos: 0
flags: 02000000
mnt_id: 14
link_type: iter
link_id: 11
prog_tag: 990e1f8152f7e54f
prog_id: 59
target_name: task
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200821184418.574122-1-yhs@fb.com
Alexei Starovoitov says:
====================
pull-request: bpf 2020-08-21
The following pull-request contains BPF updates for your *net* tree.
We've added 11 non-merge commits during the last 5 day(s) which contain
a total of 12 files changed, 78 insertions(+), 24 deletions(-).
The main changes are:
1) three fixes in BPF task iterator logic, from Yonghong.
2) fix for compressed dwarf sections in vmlinux, from Jiri.
3) fix xdp attach regression, from Andrii.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
syzbot crashed on the VM_BUG_ON_PAGE(PageTail) in munlock_vma_page(), when
called from uprobes __replace_page(). Which of many ways to fix it?
Settled on not calling when PageCompound (since Head and Tail are equals
in this context, PageCompound the usual check in uprobes.c, and the prior
use of FOLL_SPLIT_PMD will have cleared PageMlocked already).
Fixes: 5a52c9df62 ("uprobe: use FOLL_SPLIT_PMD instead of FOLL_SPLIT")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: <stable@vger.kernel.org> [5.4+]
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2008161338360.20413@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The transcript of the x86 entry code to the generic version failed to
reload the syscall number from ptregs after ptrace and seccomp have run,
which both can modify the syscall number in ptregs. It returns the original
syscall number instead which is obviously not the right thing to do.
Reload the syscall number to fix that.
Fixes: 142781e108 ("entry: Provide generic syscall entry functionality")
Reported-by: Kyle Huey <me@kylehuey.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Kyle Huey <me@kylehuey.com>
Tested-by: Kees Cook <keescook@chromium.org>
Acked-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/87blj6ifo8.fsf@nanos.tec.linutronix.de
- fix out more fallout from the dma-pool changes
(Nicolas Saenz Julienne, me)
-----BEGIN PGP SIGNATURE-----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=RQ4K
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.9-1' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
"Fix more fallout from the dma-pool changes (Nicolas Saenz Julienne,
me)"
* tag 'dma-mapping-5.9-1' of git://git.infradead.org/users/hch/dma-mapping:
dma-pool: Only allocate from CMA when in same memory zone
dma-pool: fix coherent pool allocations for IOMMU mappings
Add kernel module with user mode driver that populates bpffs with
BPF iterators.
$ mount bpffs /my/bpffs/ -t bpf
$ ls -la /my/bpffs/
total 4
drwxrwxrwt 2 root root 0 Jul 2 00:27 .
drwxr-xr-x 19 root root 4096 Jul 2 00:09 ..
-rw------- 1 root root 0 Jul 2 00:27 maps.debug
-rw------- 1 root root 0 Jul 2 00:27 progs.debug
The user mode driver will load BPF Type Formats, create BPF maps, populate BPF
maps, load two BPF programs, attach them to BPF iterators, and finally send two
bpf_link IDs back to the kernel.
The kernel will pin two bpf_links into newly mounted bpffs instance under
names "progs.debug" and "maps.debug". These two files become human readable.
$ cat /my/bpffs/progs.debug
id name attached
11 dump_bpf_map bpf_iter_bpf_map
12 dump_bpf_prog bpf_iter_bpf_prog
27 test_pkt_access
32 test_main test_pkt_access test_pkt_access
33 test_subprog1 test_pkt_access_subprog1 test_pkt_access
34 test_subprog2 test_pkt_access_subprog2 test_pkt_access
35 test_subprog3 test_pkt_access_subprog3 test_pkt_access
36 new_get_skb_len get_skb_len test_pkt_access
37 new_get_skb_ifindex get_skb_ifindex test_pkt_access
38 new_get_constant get_constant test_pkt_access
The BPF program dump_bpf_prog() in iterators.bpf.c is printing this data about
all BPF programs currently loaded in the system. This information is unstable
and will change from kernel to kernel as ".debug" suffix conveys.
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200819042759.51280-4-alexei.starovoitov@gmail.com
The program and map iterators work similar to seq_file-s.
Once the program is pinned in bpffs it can be read with "cat" tool
to print human readable output. In this case about BPF programs and maps.
For example:
$ cat /sys/fs/bpf/progs.debug
id name attached
5 dump_bpf_map bpf_iter_bpf_map
6 dump_bpf_prog bpf_iter_bpf_prog
$ cat /sys/fs/bpf/maps.debug
id name max_entries
3 iterator.rodata 1
To avoid kernel build dependency on clang 10 separate bpf skeleton generation
into manual "make" step and instead check-in generated .skel.h into git.
Unlike 'bpftool prog show' in-kernel BTF name is used (when available)
to print full name of BPF program instead of 16-byte truncated name.
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/20200819042759.51280-3-alexei.starovoitov@gmail.com
Refactor the code a bit to extract bpf_link_by_id() helper.
It's similar to existing bpf_prog_by_id().
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/20200819042759.51280-2-alexei.starovoitov@gmail.com
The old _do_fork() helper doesn't follow naming conventions of in-kernel
helpers for syscalls. The process creation cleanup in [1] didn't change the
name to something more reasonable mainly because _do_fork() was used in quite a
few places. So sending this as a separate series seemed the better strategy.
This commit does two things:
1. renames _do_fork() to kernel_clone() but keeps _do_fork() as a simple static
inline wrapper around kernel_clone().
2. Changes the return type from long to pid_t. This aligns kernel_thread() and
kernel_clone(). Also, the return value from kernel_clone that is surfaced in
fork(), vfork(), clone(), and clone3() is taken from pid_vrn() which returns
a pid_t too.
Follow-up patches will switch each caller of _do_fork() and each place where it
is referenced over to kernel_clone(). After all these changes are done, we can
remove _do_fork() completely and will only be left with kernel_clone().
[1]: 9ba27414f2 ("Merge tag 'fork-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux")
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200819104655.436656-2-christian.brauner@ubuntu.com
SD_PREFER_SIBLING is currently considered in sd_parent_degenerate() but not
in sd_degenerate(). It too hinges on load balancing, and thus won't have
any effect when set on a domain with a single group. Add it to
SD_DEGENERATE_GROUPS_MASK.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200817113003.20802-12-valentin.schneider@arm.com
We currently set this flag *only* on domains whose topology level exactly
match the level where we detect asymmetry (as returned by
asym_cpu_capacity_level()). This is rather problematic.
Say there are two clusters in the system, one with a lone big CPU and the
other with a mix of big and LITTLE CPUs (as is allowed by DynamIQ):
DIE [ ]
MC [ ][ ]
0 1 2 3 4
L L B B B
asym_cpu_capacity_level() will figure out that the MC level is the one
where all CPUs can see a CPU of max capacity, and we will thus set
SD_ASYM_CPUCAPACITY at MC level for all CPUs.
That lone big CPU will degenerate its MC domain, since it would be alone in
there, and will end up with just a DIE domain. Since the flag was only set
at MC, this CPU ends up not seeing any SD with the flag set, which is
broken.
Rather than clearing dflags at every topology level, clear it before
entering the topology level loop. This will properly propagate upwards
flags that are set starting from a certain level.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Quentin Perret <qperret@google.com>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200817113003.20802-11-valentin.schneider@arm.com
If there is only a single NUMA node in the system, the only NUMA topology
level that will be generated will be NODE (identity distance), which
doesn't have SD_SERIALIZE.
This means we don't need this special case in sd_parent_degenerate(), as
having the NODE level "naturally" covers it. Thus, remove it.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
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>
Link: https://lore.kernel.org/r/20200817113003.20802-10-valentin.schneider@arm.com
Decoding the output of /proc/sys/kernel/sched_domain/cpu*/domain*/flags has
always been somewhat annoying, as one needs to go fetch the bit -> name
mapping from the source code itself. This encoding can be saved in a script
somewhere, but that isn't safe from flags being added, removed or even
shuffled around.
What matters for debugging purposes is to get *which* flags are set in a
given domain, their associated value is pretty much meaningless.
Make the sd flags debug file output flag names.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200817113003.20802-7-valentin.schneider@arm.com
Now that we have some description of what we expect the flags layout to
be, we can use that to assert at runtime that the actual layout is sane.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
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>
Link: https://lore.kernel.org/r/20200817113003.20802-6-valentin.schneider@arm.com
This flag was introduced in 2014 by commit:
d77b3ed5c9 ("sched: Add a new SD_SHARE_POWERDOMAIN for sched_domain")
but AFAIA it was never leveraged by the scheduler. The closest thing I can
think of is EAS caring about frequency domains, and it does that by
leveraging performance domains.
Remove the flag. No change in functionality is expected.
Suggested-by: Morten Rasmussen <morten.rasmussen@arm.com>
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
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>
Link: https://lore.kernel.org/r/20200817113003.20802-2-valentin.schneider@arm.com
Currently when traversing all tasks, the next tid
is always increased by one. This may result in
visiting the same task multiple times in a
pid namespace.
This patch fixed the issue by seting the next
tid as pid_nr_ns(pid, ns) + 1, similar to
funciton next_tgid().
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Rik van Riel <riel@surriel.com>
Link: https://lore.kernel.org/bpf/20200818222310.2181500-1-yhs@fb.com
In our production system, we observed rcu stalls when
'bpftool prog` is running.
rcu: INFO: rcu_sched self-detected stall on CPU
rcu: \x097-....: (20999 ticks this GP) idle=302/1/0x4000000000000000 softirq=1508852/1508852 fqs=4913
\x09(t=21031 jiffies g=2534773 q=179750)
NMI backtrace for cpu 7
CPU: 7 PID: 184195 Comm: bpftool Kdump: loaded Tainted: G W 5.8.0-00004-g68bfc7f8c1b4 #6
Hardware name: Quanta Twin Lakes MP/Twin Lakes Passive MP, BIOS F09_3A17 05/03/2019
Call Trace:
<IRQ>
dump_stack+0x57/0x70
nmi_cpu_backtrace.cold+0x14/0x53
? lapic_can_unplug_cpu.cold+0x39/0x39
nmi_trigger_cpumask_backtrace+0xb7/0xc7
rcu_dump_cpu_stacks+0xa2/0xd0
rcu_sched_clock_irq.cold+0x1ff/0x3d9
? tick_nohz_handler+0x100/0x100
update_process_times+0x5b/0x90
tick_sched_timer+0x5e/0xf0
__hrtimer_run_queues+0x12a/0x2a0
hrtimer_interrupt+0x10e/0x280
__sysvec_apic_timer_interrupt+0x51/0xe0
asm_call_on_stack+0xf/0x20
</IRQ>
sysvec_apic_timer_interrupt+0x6f/0x80
asm_sysvec_apic_timer_interrupt+0x12/0x20
RIP: 0010:task_file_seq_get_next+0x71/0x220
Code: 00 00 8b 53 1c 49 8b 7d 00 89 d6 48 8b 47 20 44 8b 18 41 39 d3 76 75 48 8b 4f 20 8b 01 39 d0 76 61 41 89 d1 49 39 c1 48 19 c0 <48> 8b 49 08 21 d0 48 8d 04 c1 4c 8b 08 4d 85 c9 74 46 49 8b 41 38
RSP: 0018:ffffc90006223e10 EFLAGS: 00000297
RAX: ffffffffffffffff RBX: ffff888f0d172388 RCX: ffff888c8c07c1c0
RDX: 00000000000f017b RSI: 00000000000f017b RDI: ffff888c254702c0
RBP: ffffc90006223e68 R08: ffff888be2a1c140 R09: 00000000000f017b
R10: 0000000000000002 R11: 0000000000100000 R12: ffff888f23c24118
R13: ffffc90006223e60 R14: ffffffff828509a0 R15: 00000000ffffffff
task_file_seq_next+0x52/0xa0
bpf_seq_read+0xb9/0x320
vfs_read+0x9d/0x180
ksys_read+0x5f/0xe0
do_syscall_64+0x38/0x60
entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f8815f4f76e
Code: c0 e9 f6 fe ff ff 55 48 8d 3d 76 70 0a 00 48 89 e5 e8 36 06 02 00 66 0f 1f 44 00 00 64 8b 04 25 18 00 00 00 85 c0 75 14 0f 05 <48> 3d 00 f0 ff ff 77 52 c3 66 0f 1f 84 00 00 00 00 00 55 48 89 e5
RSP: 002b:00007fff8f9df578 EFLAGS: 00000246 ORIG_RAX: 0000000000000000
RAX: ffffffffffffffda RBX: 000000000170b9c0 RCX: 00007f8815f4f76e
RDX: 0000000000001000 RSI: 00007fff8f9df5b0 RDI: 0000000000000007
RBP: 00007fff8f9e05f0 R08: 0000000000000049 R09: 0000000000000010
R10: 00007f881601fa40 R11: 0000000000000246 R12: 00007fff8f9e05a8
R13: 00007fff8f9e05a8 R14: 0000000001917f90 R15: 000000000000e22e
Note that `bpftool prog` actually calls a task_file bpf iterator
program to establish an association between prog/map/link/btf anon
files and processes.
In the case where the above rcu stall occured, we had a process
having 1587 tasks and each task having roughly 81305 files.
This implied 129 million bpf prog invocations. Unfortunwtely none of
these files are prog/map/link/btf files so bpf iterator/prog needs
to traverse all these files and not able to return to user space
since there are no seq_file buffer overflow.
This patch fixed the issue in bpf_seq_read() to limit the number
of visited objects. If the maximum number of visited objects is
reached, no more objects will be visited in the current syscall.
If there is nothing written in the seq_file buffer, -EAGAIN will
return to the user so user can try again.
The maximum number of visited objects is set at 1 million.
In our Intel Xeon D-2191 2.3GHZ 18-core server, bpf_seq_read()
visiting 1 million files takes around 0.18 seconds.
We did not use cond_resched() since for some iterators, e.g.,
netlink iterator, where rcu read_lock critical section spans between
consecutive seq_ops->next(), which makes impossible to do cond_resched()
in the key while loop of function bpf_seq_read().
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Cc: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/bpf/20200818222309.2181348-1-yhs@fb.com
Current perf assumes that events in a group are independent. Close an
event doesn't impact the value of the other events in the same group.
If the closed event is a member, after the event closure, other events
are still running like a group. If the closed event is a leader, other
events are running as singleton events.
Add PERF_EV_CAP_SIBLING to allow events to indicate they require being
part of a group, and when the leader dies they cannot exist
independently.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200723171117.9918-8-kan.liang@linux.intel.com
Checkpatch tool reports
"ERROR: do not initialise globals/statics to 0"
To fix this, audit_sig_sid is uninitialized
As this is stored in the .bss section,
the compiler can initialize the variable automatically.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Variables sig_pid, audit_sig_uid and audit_sig_sid
are only used in the audit.c file across the kernel
Hence it appears no reason for declaring them as globals
This patch removes their global declarations from the .h file
and change them into static in the .c file.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Pull networking fixes from David Miller:
"Another batch of fixes:
1) Remove nft_compat counter flush optimization, it generates warnings
from the refcount infrastructure. From Florian Westphal.
2) Fix BPF to search for build id more robustly, from Jiri Olsa.
3) Handle bogus getopt lengths in ebtables, from Florian Westphal.
4) Infoleak and other fixes to j1939 CAN driver, from Eric Dumazet and
Oleksij Rempel.
5) Reset iter properly on mptcp sendmsg() error, from Florian
Westphal.
6) Show a saner speed in bonding broadcast mode, from Jarod Wilson.
7) Various kerneldoc fixes in bonding and elsewhere, from Lee Jones.
8) Fix double unregister in bonding during namespace tear down, from
Cong Wang.
9) Disable RP filter during icmp_redirect selftest, from David Ahern"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (75 commits)
otx2_common: Use devm_kcalloc() in otx2_config_npa()
net: qrtr: fix usage of idr in port assignment to socket
selftests: disable rp_filter for icmp_redirect.sh
Revert "net: xdp: pull ethernet header off packet after computing skb->protocol"
phylink: <linux/phylink.h>: fix function prototype kernel-doc warning
mptcp: sendmsg: reset iter on error redux
net: devlink: Remove overzealous WARN_ON with snapshots
tipc: not enable tipc when ipv6 works as a module
tipc: fix uninit skb->data in tipc_nl_compat_dumpit()
net: Fix potential wrong skb->protocol in skb_vlan_untag()
net: xdp: pull ethernet header off packet after computing skb->protocol
ipvlan: fix device features
bonding: fix a potential double-unregister
can: j1939: add rxtimer for multipacket broadcast session
can: j1939: abort multipacket broadcast session when timeout occurs
can: j1939: cancel rxtimer on multipacket broadcast session complete
can: j1939: fix support for multipacket broadcast message
net: fddi: skfp: cfm: Remove seemingly unused variable 'ID_sccs'
net: fddi: skfp: cfm: Remove set but unused variable 'oldstate'
net: fddi: skfp: smt: Remove seemingly unused variable 'ID_sccs'
...
With latest `bpftool prog` command, we observed the following kernel
panic.
BUG: kernel NULL pointer dereference, address: 0000000000000000
#PF: supervisor instruction fetch in kernel mode
#PF: error_code(0x0010) - not-present page
PGD dfe894067 P4D dfe894067 PUD deb663067 PMD 0
Oops: 0010 [#1] SMP
CPU: 9 PID: 6023 ...
RIP: 0010:0x0
Code: Bad RIP value.
RSP: 0000:ffffc900002b8f18 EFLAGS: 00010286
RAX: ffff8883a405f400 RBX: ffff888e46a6bf00 RCX: 000000008020000c
RDX: 0000000000000000 RSI: 0000000000000001 RDI: ffff8883a405f400
RBP: ffff888e46a6bf50 R08: 0000000000000000 R09: ffffffff81129600
R10: ffff8883a405f300 R11: 0000160000000000 R12: 0000000000002710
R13: 000000e9494b690c R14: 0000000000000202 R15: 0000000000000009
FS: 00007fd9187fe700(0000) GS:ffff888e46a40000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffffffffffffffd6 CR3: 0000000de5d33002 CR4: 0000000000360ee0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
rcu_core+0x1a4/0x440
__do_softirq+0xd3/0x2c8
irq_exit+0x9d/0xa0
smp_apic_timer_interrupt+0x68/0x120
apic_timer_interrupt+0xf/0x20
</IRQ>
RIP: 0033:0x47ce80
Code: Bad RIP value.
RSP: 002b:00007fd9187fba40 EFLAGS: 00000206 ORIG_RAX: ffffffffffffff13
RAX: 0000000000000002 RBX: 00007fd931789160 RCX: 000000000000010c
RDX: 00007fd9308cdfb4 RSI: 00007fd9308cdfb4 RDI: 00007ffedd1ea0a8
RBP: 00007fd9187fbab0 R08: 000000000000000e R09: 000000000000002a
R10: 0000000000480210 R11: 00007fd9187fc570 R12: 00007fd9316cc400
R13: 0000000000000118 R14: 00007fd9308cdfb4 R15: 00007fd9317a9380
After further analysis, the bug is triggered by
Commit eaaacd2391 ("bpf: Add task and task/file iterator targets")
which introduced task_file bpf iterator, which traverses all open file
descriptors for all tasks in the current namespace.
The latest `bpftool prog` calls a task_file bpf program to traverse
all files in the system in order to associate processes with progs/maps, etc.
When traversing files for a given task, rcu read_lock is taken to
access all files in a file_struct. But it used get_file() to grab
a file, which is not right. It is possible file->f_count is 0 and
get_file() will unconditionally increase it.
Later put_file() may cause all kind of issues with the above
as one of sympotoms.
The failure can be reproduced with the following steps in a few seconds:
$ cat t.c
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#define N 10000
int fd[N];
int main() {
int i;
for (i = 0; i < N; i++) {
fd[i] = open("./note.txt", 'r');
if (fd[i] < 0) {
fprintf(stderr, "failed\n");
return -1;
}
}
for (i = 0; i < N; i++)
close(fd[i]);
return 0;
}
$ gcc -O2 t.c
$ cat run.sh
#/bin/bash
for i in {1..100}
do
while true; do ./a.out; done &
done
$ ./run.sh
$ while true; do bpftool prog >& /dev/null; done
This patch used get_file_rcu() which only grabs a file if the
file->f_count is not zero. This is to ensure the file pointer
is always valid. The above reproducer did not fail for more
than 30 minutes.
Fixes: eaaacd2391 ("bpf: Add task and task/file iterator targets")
Suggested-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Link: https://lore.kernel.org/bpf/20200817174214.252601-1-yhs@fb.com
Impose a limit on the number of watches that a user can hold so that
they can't use this mechanism to fill up all the available memory.
This is done by putting a counter in user_struct that's incremented when
a watch is allocated and decreased when it is released. If the number
exceeds the RLIMIT_NOFILE limit, the watch is rejected with EAGAIN.
This can be tested by the following means:
(1) Create a watch queue and attach it to fd 5 in the program given - in
this case, bash:
keyctl watch_session /tmp/nlog /tmp/gclog 5 bash
(2) In the shell, set the maximum number of files to, say, 99:
ulimit -n 99
(3) Add 200 keyrings:
for ((i=0; i<200; i++)); do keyctl newring a$i @s || break; done
(4) Try to watch all of the keyrings:
for ((i=0; i<200; i++)); do echo $i; keyctl watch_add 5 %:a$i || break; done
This should fail when the number of watches belonging to the user hits
99.
(5) Remove all the keyrings and all of those watches should go away:
for ((i=0; i<200; i++)); do keyctl unlink %:a$i; done
(6) Kill off the watch queue by exiting the shell spawned by
watch_session.
Fixes: c73be61ced ("pipe: Add general notification queue support")
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----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=T+fx
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.9-2020-08-15' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
"A few differerent things in here.
Seems like syzbot got some more io_uring bits wired up, and we got a
handful of reports and the associated fixes are in here.
General fixes too, and a lot of them marked for stable.
Lastly, a bit of fallout from the async buffered reads, where we now
more easily trigger short reads. Some applications don't really like
that, so the io_read() code now handles short reads internally, and
got a cleanup along the way so that it's now easier to read (and
documented). We're now passing tests that failed before"
* tag 'io_uring-5.9-2020-08-15' of git://git.kernel.dk/linux-block:
io_uring: short circuit -EAGAIN for blocking read attempt
io_uring: sanitize double poll handling
io_uring: internally retry short reads
io_uring: retain iov_iter state over io_read/io_write calls
task_work: only grab task signal lock when needed
io_uring: enable lookup of links holding inflight files
io_uring: fail poll arm on queue proc failure
io_uring: hold 'ctx' reference around task_work queue + execute
fs: RWF_NOWAIT should imply IOCB_NOIO
io_uring: defer file table grabbing request cleanup for locked requests
io_uring: add missing REQ_F_COMP_LOCKED for nested requests
io_uring: fix recursive completion locking on oveflow flush
io_uring: use TWA_SIGNAL for task_work uncondtionally
io_uring: account locked memory before potential error case
io_uring: set ctx sq/cq entry count earlier
io_uring: Fix NULL pointer dereference in loop_rw_iter()
io_uring: add comments on how the async buffered read retry works
io_uring: io_async_buf_func() need not test page bit
changes to arch/sh.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.4.12 (GNU/Linux)
iQEcBAABAgAGBQJfODUiAAoJELcQ+SIFb8Hau0wH/iPeZyv0EhIwL41OPrWhm5wb
26MNWPvPjYIpKVpr0HMXiffILv595ntvrH0Ujnh1+e8J2kRj0eT+T91UkoyGSfav
oWmjgcG3NRK6p9882Oo8Xavjr1cTTclOmmDInR4lpAcfIBXkeq2eX0R1h2IuGdNM
idGlXhJMkgV+xTlgZy7pYmw5pvFMqL5j7fAUQxm0UoY9kbu8Ac4bOR5WrqtFpkjt
xTh9141YvSSfpRx9uMzrQLuUYGzGePhnjUGSUf/b1deYG/33lNtzhHr+QMK6BpXr
zdhFalJP40+m+2tG0nCBpAIZcWiOLGb23in5n/trFx3BGZfUf5EKnhZEGUYeE7Q=
=XWDn
-----END PGP SIGNATURE-----
Merge tag 'sh-for-5.9' of git://git.libc.org/linux-sh
Pull arch/sh updates from Rich Felker:
"Cleanup, SECCOMP_FILTER support, message printing fixes, and other
changes to arch/sh"
* tag 'sh-for-5.9' of git://git.libc.org/linux-sh: (34 commits)
sh: landisk: Add missing initialization of sh_io_port_base
sh: bring syscall_set_return_value in line with other architectures
sh: Add SECCOMP_FILTER
sh: Rearrange blocks in entry-common.S
sh: switch to copy_thread_tls()
sh: use the generic dma coherent remap allocator
sh: don't allow non-coherent DMA for NOMMU
dma-mapping: consolidate the NO_DMA definition in kernel/dma/Kconfig
sh: unexport register_trapped_io and match_trapped_io_handler
sh: don't include <asm/io_trapped.h> in <asm/io.h>
sh: move the ioremap implementation out of line
sh: move ioremap_fixed details out of <asm/io.h>
sh: remove __KERNEL__ ifdefs from non-UAPI headers
sh: sort the selects for SUPERH alphabetically
sh: remove -Werror from Makefiles
sh: Replace HTTP links with HTTPS ones
arch/sh/configs: remove obsolete CONFIG_SOC_CAMERA*
sh: stacktrace: Remove stacktrace_ops.stack()
sh: machvec: Modernize printing of kernel messages
sh: pci: Modernize printing of kernel messages
...
- Fix mitigation state sysfs output
- Fix an FPU xstate/sxave code assumption bug triggered by Architectural LBR support
- Fix Lightning Mountain SoC TSC frequency enumeration bug
- Fix kexec debug output
- Fix kexec memory range assumption bug
- Fix a boundary condition in the crash kernel code
- Optimize porgatory.ro generation a bit
- Enable ACRN guests to use X2APIC mode
- Reduce a __text_poke() IRQs-off critical section for the benefit of PREEMPT_RT
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=fvpv
-----END PGP SIGNATURE-----
Merge tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 fixes from Ingo Molnar:
"Misc fixes and small updates all around the place:
- Fix mitigation state sysfs output
- Fix an FPU xstate/sxave code assumption bug triggered by
Architectural LBR support
- Fix Lightning Mountain SoC TSC frequency enumeration bug
- Fix kexec debug output
- Fix kexec memory range assumption bug
- Fix a boundary condition in the crash kernel code
- Optimize porgatory.ro generation a bit
- Enable ACRN guests to use X2APIC mode
- Reduce a __text_poke() IRQs-off critical section for the benefit of
PREEMPT_RT"
* tag 'x86-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/alternatives: Acquire pte lock with interrupts enabled
x86/bugs/multihit: Fix mitigation reporting when VMX is not in use
x86/fpu/xstate: Fix an xstate size check warning with architectural LBRs
x86/purgatory: Don't generate debug info for purgatory.ro
x86/tsr: Fix tsc frequency enumeration bug on Lightning Mountain SoC
kexec_file: Correctly output debugging information for the PT_LOAD ELF header
kexec: Improve & fix crash_exclude_mem_range() to handle overlapping ranges
x86/crash: Correct the address boundary of function parameters
x86/acrn: Remove redundant chars from ACRN signature
x86/acrn: Allow ACRN guest to use X2APIC mode
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=ffEv
-----END PGP SIGNATURE-----
Merge tag 'sched-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler fixes from Ingo Molnar:
"Two fixes: fix a new tracepoint's output value, and fix the formatting
of show-state syslog printouts"
* tag 'sched-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/debug: Fix the alignment of the show-state debug output
sched: Fix use of count for nr_running tracepoint
plus a RAPL HW-enablement for Intel SPR platforms.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=NsxB
-----END PGP SIGNATURE-----
Merge tag 'perf-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf fixes from Ingo Molnar:
"Misc fixes, an expansion of perf syscall access to CAP_PERFMON
privileged tools, plus a RAPL HW-enablement for Intel SPR platforms"
* tag 'perf-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/rapl: Add support for Intel SPR platform
perf/x86/rapl: Support multiple RAPL unit quirks
perf/x86/rapl: Fix missing psys sysfs attributes
hw_breakpoint: Remove unused __register_perf_hw_breakpoint() declaration
kprobes: Remove show_registers() function prototype
perf/core: Take over CAP_SYS_PTRACE creds to CAP_PERFMON capability
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=T2pv
-----END PGP SIGNATURE-----
Merge tag 'locking-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking fixlets from Ingo Molnar:
"A documentation fix and a 'fallthrough' macro update"
* tag 'locking-urgent-2020-08-15' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
futex: Convert to use the preferred 'fallthrough' macro
Documentation/locking/locktypes: Fix a typo
Merge more updates from Andrew Morton:
"Subsystems affected by this patch series: mm/hotfixes, lz4, exec,
mailmap, mm/thp, autofs, sysctl, mm/kmemleak, mm/misc and lib"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (35 commits)
virtio: pci: constify ioreadX() iomem argument (as in generic implementation)
ntb: intel: constify ioreadX() iomem argument (as in generic implementation)
rtl818x: constify ioreadX() iomem argument (as in generic implementation)
iomap: constify ioreadX() iomem argument (as in generic implementation)
sh: use generic strncpy()
sh: clkfwk: remove r8/r16/r32
include/asm-generic/vmlinux.lds.h: align ro_after_init
mm: annotate a data race in page_zonenum()
mm/swap.c: annotate data races for lru_rotate_pvecs
mm/rmap: annotate a data race at tlb_flush_batched
mm/mempool: fix a data race in mempool_free()
mm/list_lru: fix a data race in list_lru_count_one
mm/memcontrol: fix a data race in scan count
mm/page_counter: fix various data races at memsw
mm/swapfile: fix and annotate various data races
mm/filemap.c: fix a data race in filemap_fault()
mm/swap_state: mark various intentional data races
mm/page_io: mark various intentional data races
mm/frontswap: mark various intentional data races
mm/kmemleak: silence KCSAN splats in checksum
...
Since commit 61a47c1ad3 ("sysctl: Remove the sysctl system call"),
sys_sysctl is actually unavailable: any input can only return an error.
We have been warning about people using the sysctl system call for years
and believe there are no more users. Even if there are users of this
interface if they have not complained or fixed their code by now they
probably are not going to, so there is no point in warning them any
longer.
So completely remove sys_sysctl on all architectures.
[nixiaoming@huawei.com: s390: fix build error for sys_call_table_emu]
Link: http://lkml.kernel.org/r/20200618141426.16884-1-nixiaoming@huawei.com
Signed-off-by: Xiaoming Ni <nixiaoming@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Will Deacon <will@kernel.org> [arm/arm64]
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Bin Meng <bin.meng@windriver.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: chenzefeng <chenzefeng2@huawei.com>
Cc: Christian Borntraeger <borntraeger@de.ibm.com>
Cc: Christian Brauner <christian@brauner.io>
Cc: Chris Zankel <chris@zankel.net>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Diego Elio Pettenò <flameeyes@flameeyes.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Dominik Brodowski <linux@dominikbrodowski.net>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Helge Deller <deller@gmx.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kars de Jong <jongk@linux-m68k.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Marco Elver <elver@google.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Max Filippov <jcmvbkbc@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Miklos Szeredi <mszeredi@redhat.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Olof Johansson <olof@lixom.net>
Cc: Paul Burton <paulburton@kernel.org>
Cc: "Paul E. McKenney" <paulmck@kernel.org>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Rich Felker <dalias@libc.org>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sami Tolvanen <samitolvanen@google.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Sudeep Holla <sudeep.holla@arm.com>
Cc: Sven Schnelle <svens@stackframe.org>
Cc: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tony Luck <tony.luck@intel.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Zhou Yanjie <zhouyanjie@wanyeetech.com>
Link: http://lkml.kernel.org/r/20200616030734.87257-1-nixiaoming@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Daniel Borkmann says:
====================
pull-request: bpf 2020-08-15
The following pull-request contains BPF updates for your *net* tree.
We've added 23 non-merge commits during the last 4 day(s) which contain
a total of 32 files changed, 421 insertions(+), 141 deletions(-).
The main changes are:
1) Fix sock_ops ctx access splat due to register override, from John Fastabend.
2) Batch of various fixes to libbpf, bpftool, and selftests when testing build
in 32-bit mode, from Andrii Nakryiko.
3) Fix vmlinux.h generation on ARM by mapping GCC built-in types (__Poly*_t)
to equivalent ones clang can work with, from Jean-Philippe Brucker.
4) Fix build_id lookup in bpf_get_stackid() helper by walking all NOTE ELF
sections instead of just first, from Jiri Olsa.
5) Avoid use of __builtin_offsetof() in libbpf for CO-RE, from Yonghong Song.
6) Fix segfault in test_mmap due to inconsistent length params, from Jianlin Lv.
7) Don't override errno in libbpf when logging errors, from Toke Høiland-Jørgensen.
8) Fix v4_to_v6 sockaddr conversion in sk_lookup test, from Stanislav Fomichev.
9) Add link to bpf-helpers(7) man page to BPF doc, from Joe Stringer.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
This remoes the code from the COW path to call debug_dma_assert_idle(),
which was added many years ago.
Google shows that it hasn't caught anything in the 6+ years we've had it
apart from a false positive, and Hugh just noticed how it had a very
unfortunate spinlock serialization in the COW path.
He fixed that issue the previous commit (a85ffd59bd: "dma-debug: fix
debug_dma_assert_idle(), use rcu_read_lock()"), but let's see if anybody
even notices when we remove this function entirely.
NOTE! We keep the dma tracking infrastructure that was added by the
commit that introduced it. Partly to make it easier to resurrect this
debug code if we ever deside to, and partly because that tracking by pfn
and offset looks quite reasonable.
The problem with this debug code was simply that it was expensive and
didn't seem worth it, not that it was wrong per se.
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since commit 2a9127fcf2 ("mm: rewrite wait_on_page_bit_common()
logic") improved unlock_page(), it has become more noticeable how
cow_user_page() in a kernel with CONFIG_DMA_API_DEBUG=y can create and
suffer from heavy contention on DMA debug's radix_lock in
debug_dma_assert_idle().
It is only doing a lookup: use rcu_read_lock() and rcu_read_unlock()
instead; though that does require the static ents[] to be moved
onstack...
...but, hold on, isn't that radix_tree_gang_lookup() and loop doing
quite the wrong thing: searching CACHELINES_PER_PAGE entries for an
exact match with the first cacheline of the page in question?
radix_tree_gang_lookup() is the right tool for the job, but we need
nothing more than to check the first entry it can find, reporting if
that falls anywhere within the page.
(Is RCU safe here? As safe as using the spinlock was. The entries are
never freed, so don't need to be freed by RCU. They may be reused, and
there is a faint chance of a race, with an offending entry reused while
printing its error info; but the spinlock did not prevent that either,
and I agree that it's not worth worrying about. ]
[ Side noe: this patch is a clear improvement to the status quo, but the
next patch will be removing this debug function entirely.
But just in case we decide we want to resurrect the debugging code
some day, I'm first applying this improvement patch so that it doesn't
get lost - Linus ]
Fixes: 3b7a6418c7 ("dma debug: account for cachelines and read-only mappings in overlap tracking")
Signed-off-by: Hugh Dickins <hughd@google.com>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
- Preparatory work to allow S390 to switch over to the generic VDSO
implementation.
S390 requires that the VDSO data pointer is handed in to the counter
read function when time namespace support is enabled. Adding the pointer
is a NOOP for all other architectures because the compiler is supposed
to optimize that out when it is unused in the architecture specific
inline. The change also solved a similar problem for MIPS which
fortunately has time namespaces not yet enabled.
S390 needs to update clock related VDSO data independent of the
timekeeping updates. This was solved so far with yet another sequence
counter in the S390 implementation. A better solution is to utilize the
already existing VDSO sequence count for this. The core code now exposes
helper functions which allow to serialize against the timekeeper code
and against concurrent readers.
S390 needs extra data for their clock readout function. The initial
common VDSO data structure did not provide a way to add that. It now has
an embedded architecture specific struct embedded which defaults to an
empty struct.
Doing this now avoids tree dependencies and conflicts post rc1 and
allows all other architectures which work on generic VDSO support to
work from a common upstream base.
- A trivial comment fix.
-----BEGIN PGP SIGNATURE-----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=y8Z5
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timekeeping updates from Thomas Gleixner:
"A set of timekeeping/VDSO updates:
- Preparatory work to allow S390 to switch over to the generic VDSO
implementation.
S390 requires that the VDSO data pointer is handed in to the
counter read function when time namespace support is enabled.
Adding the pointer is a NOOP for all other architectures because
the compiler is supposed to optimize that out when it is unused in
the architecture specific inline. The change also solved a similar
problem for MIPS which fortunately has time namespaces not yet
enabled.
S390 needs to update clock related VDSO data independent of the
timekeeping updates. This was solved so far with yet another
sequence counter in the S390 implementation. A better solution is
to utilize the already existing VDSO sequence count for this. The
core code now exposes helper functions which allow to serialize
against the timekeeper code and against concurrent readers.
S390 needs extra data for their clock readout function. The initial
common VDSO data structure did not provide a way to add that. It
now has an embedded architecture specific struct embedded which
defaults to an empty struct.
Doing this now avoids tree dependencies and conflicts post rc1 and
allows all other architectures which work on generic VDSO support
to work from a common upstream base.
- A trivial comment fix"
* tag 'timers-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
time: Delete repeated words in comments
lib/vdso: Allow to add architecture-specific vdso data
timekeeping/vsyscall: Provide vdso_update_begin/end()
vdso/treewide: Add vdso_data pointer argument to __arch_get_hw_counter()
posix CPU timers into task work context. The tick interrupt is reduced to a
quick check which queues the work which is doing the heavy lifting before
returning to user space or going back to guest mode. Moving this out is
deferring the signal delivery slightly but posix CPU timers are inaccurate
by nature as they depend on the tick so there is no real damage. The
relevant test cases all passed.
This lifts the last offender for RT out of the hard interrupt context tick
handler, but it also has the general benefit that the actual heavy work is
accounted to the task/process and not to the tick interrupt itself.
Further optimizations are possible to break long sighand lock hold and
interrupt disabled (on !RT kernels) times when a massive amount of posix
CPU timers (which are unpriviledged) is armed for a task/process.
This is currently only enabled for x86 because the architecture has to
ensure that task work is handled in KVM before entering a guest, which was
just established for x86 with the new common entry/exit code which got
merged post 5.8 and is not the case for other KVM architectures.
-----BEGIN PGP SIGNATURE-----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=Reot
-----END PGP SIGNATURE-----
Merge tag 'timers-core-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull more timer updates from Thomas Gleixner:
"A set of posix CPU timer changes which allows to defer the heavy work
of posix CPU timers into task work context. The tick interrupt is
reduced to a quick check which queues the work which is doing the
heavy lifting before returning to user space or going back to guest
mode. Moving this out is deferring the signal delivery slightly but
posix CPU timers are inaccurate by nature as they depend on the tick
so there is no real damage. The relevant test cases all passed.
This lifts the last offender for RT out of the hard interrupt context
tick handler, but it also has the general benefit that the actual
heavy work is accounted to the task/process and not to the tick
interrupt itself.
Further optimizations are possible to break long sighand lock hold and
interrupt disabled (on !RT kernels) times when a massive amount of
posix CPU timers (which are unpriviledged) is armed for a
task/process.
This is currently only enabled for x86 because the architecture has to
ensure that task work is handled in KVM before entering a guest, which
was just established for x86 with the new common entry/exit code which
got merged post 5.8 and is not the case for other KVM architectures"
* tag 'timers-core-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86: Select POSIX_CPU_TIMERS_TASK_WORK
posix-cpu-timers: Provide mechanisms to defer timer handling to task_work
posix-cpu-timers: Split run_posix_cpu_timers()
unlock the descriptor lock.
-----BEGIN PGP SIGNATURE-----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=/wh/
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Thomas Gleixner:
"Two fixes in the core interrupt code which ensure that all error exits
unlock the descriptor lock"
* tag 'irq-urgent-2020-08-14' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq: Unlock irq descriptor after errors
genirq/PM: Always unlock IRQ descriptor in rearm_wake_irq()
Summary of modules changes for the 5.9 merge window:
- Have modules that use symbols from proprietary modules inherit the
TAINT_PROPRIETARY_MODULE taint, in an effort to prevent GPL shim modules that
are used to circumvent _GPL exports. These are modules that claim to be GPL
licensed while also using symbols from proprietary modules. Such modules will
be rejected while non-GPL modules will inherit the proprietary taint.
- Module export space cleanup. Unexport symbols that are unused outside of
module.c or otherwise used in only built-in code.
Signed-off-by: Jessica Yu <jeyu@kernel.org>
-----BEGIN PGP SIGNATURE-----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=Qlem
-----END PGP SIGNATURE-----
Merge tag 'modules-for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux
Pull module updates from Jessica Yu:
"The most important change would be Christoph Hellwig's patch
implementing proprietary taint inheritance, in an effort to discourage
the creation of GPL "shim" modules that interface between GPL symbols
and proprietary symbols.
Summary:
- Have modules that use symbols from proprietary modules inherit the
TAINT_PROPRIETARY_MODULE taint, in an effort to prevent GPL shim
modules that are used to circumvent _GPL exports. These are modules
that claim to be GPL licensed while also using symbols from
proprietary modules. Such modules will be rejected while non-GPL
modules will inherit the proprietary taint.
- Module export space cleanup. Unexport symbols that are unused
outside of module.c or otherwise used in only built-in code"
* tag 'modules-for-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/jeyu/linux:
modules: inherit TAINT_PROPRIETARY_MODULE
modules: return licensing information from find_symbol
modules: rename the licence field in struct symsearch to license
modules: unexport __module_address
modules: unexport __module_text_address
modules: mark each_symbol_section static
modules: mark find_symbol static
modules: mark ref_module static
modules: linux/moduleparam.h: drop duplicated word in a comment
There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. To get around this double check CMA's placement before
allocating from it.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
When allocating coherent pool memory for an IOMMU mapping we don't care
about the DMA mask. Move the guess for the initial GFP mask into the
dma_direct_alloc_pages and pass dma_coherent_ok as a function pointer
argument so that it doesn't get applied to the IOMMU case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Amit Pundir <amit.pundir@linaro.org>
Current sysrq(t) output task fields name are not aligned with
actual task fields value, e.g.:
kernel: sysrq: Show State
kernel: task PC stack pid father
kernel: systemd S12456 1 0 0x00000000
kernel: Call Trace:
kernel: ? __schedule+0x240/0x740
To make it more readable, print fields name together with task fields
value in the same line, with fixed width:
kernel: sysrq: Show State
kernel: task:systemd state:S stack:12920 pid: 1 ppid: 0 flags:0x00000000
kernel: Call Trace:
kernel: __schedule+0x282/0x620
Signed-off-by: Libing Zhou <libing.zhou@nokia-sbell.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200814030236.37835-1-libing.zhou@nokia-sbell.com
Pull networking fixes from David Miller:
"Some merge window fallout, some longer term fixes:
1) Handle headroom properly in lapbether and x25_asy drivers, from
Xie He.
2) Fetch MAC address from correct r8152 device node, from Thierry
Reding.
3) In the sw kTLS path we should allow MSG_CMSG_COMPAT in sendmsg,
from Rouven Czerwinski.
4) Correct fdputs in socket layer, from Miaohe Lin.
5) Revert troublesome sockptr_t optimization, from Christoph Hellwig.
6) Fix TCP TFO key reading on big endian, from Jason Baron.
7) Missing CAP_NET_RAW check in nfc, from Qingyu Li.
8) Fix inet fastreuse optimization with tproxy sockets, from Tim
Froidcoeur.
9) Fix 64-bit divide in new SFC driver, from Edward Cree.
10) Add a tracepoint for prandom_u32 so that we can more easily
perform usage analysis. From Eric Dumazet.
11) Fix rwlock imbalance in AF_PACKET, from John Ogness"
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (49 commits)
net: openvswitch: introduce common code for flushing flows
af_packet: TPACKET_V3: fix fill status rwlock imbalance
random32: add a tracepoint for prandom_u32()
Revert "ipv4: tunnel: fix compilation on ARCH=um"
net: accept an empty mask in /sys/class/net/*/queues/rx-*/rps_cpus
net: ethernet: stmmac: Disable hardware multicast filter
net: stmmac: dwmac1000: provide multicast filter fallback
ipv4: tunnel: fix compilation on ARCH=um
vsock: fix potential null pointer dereference in vsock_poll()
sfc: fix ef100 design-param checking
net: initialize fastreuse on inet_inherit_port
net: refactor bind_bucket fastreuse into helper
net: phy: marvell10g: fix null pointer dereference
net: Fix potential memory leak in proto_register()
net: qcom/emac: add missed clk_disable_unprepare in error path of emac_clks_phase1_init
ionic_lif: Use devm_kcalloc() in ionic_qcq_alloc()
net/nfc/rawsock.c: add CAP_NET_RAW check.
hinic: fix strncpy output truncated compile warnings
drivers/net/wan/x25_asy: Added needed_headroom and a skb->len check
net/tls: Fix kmap usage
...
If JOBCTL_TASK_WORK is already set on the targeted task, then we need
not go through {lock,unlock}_task_sighand() to set it again and queue
a signal wakeup. This is safe as we're checking it _after_ adding the
new task_work with cmpxchg().
The ordering is as follows:
task_work_add() get_signal()
--------------------------------------------------------------
STORE(task->task_works, new_work); STORE(task->jobctl);
mb(); mb();
LOAD(task->jobctl); LOAD(task->task_works);
This speeds up TWA_SIGNAL handling quite a bit, which is important now
that io_uring is relying on it for all task_work deliveries.
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Jann Horn <jannh@google.com>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
In irq_set_irqchip_state(), the irq descriptor is not unlocked after an
error is encountered. While that should never happen in practice, a buggy
driver may trigger it. This would result in a lockup, so fix it.
Fixes: 1d0326f352 ("genirq: Check irq_data_get_irq_chip() return value before use")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200811180012.80269-1-linux@roeck-us.net
Currently when we look for build id within bpf_get_stackid helper
call, we check the first NOTE section and we fail if build id is
not there.
However on some system (Fedora) there can be multiple NOTE sections
in binaries and build id data is not always the first one, like:
$ readelf -a /usr/bin/ls
...
[ 2] .note.gnu.propert NOTE 0000000000000338 00000338
0000000000000020 0000000000000000 A 0 0 8358
[ 3] .note.gnu.build-i NOTE 0000000000000358 00000358
0000000000000024 0000000000000000 A 0 0 437c
[ 4] .note.ABI-tag NOTE 000000000000037c 0000037c
...
So the stack_map_get_build_id function will fail on build id retrieval
and fallback to BPF_STACK_BUILD_ID_IP.
This patch is changing the stack_map_get_build_id code to iterate
through all the NOTE sections and try to get build id data from
each of them.
When tracing on sched_switch tracepoint that does bpf_get_stackid
helper call kernel build, I can see about 60% increase of successful
build id retrieval. The rest seems fails on -EFAULT.
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/20200812123102.20032-1-jolsa@kernel.org
Backmerging drm-next into drm-misc-next for nouveau and panel updates.
Resolves a conflict between ttm and nouveau, where struct ttm_mem_res got
renamed to struct ttm_resource.
Signed-off-by: Thomas Zimmermann <tzimmermann@suse.de>
Merge more updates from Andrew Morton:
- most of the rest of MM (memcg, hugetlb, vmscan, proc, compaction,
mempolicy, oom-kill, hugetlbfs, migration, thp, cma, util,
memory-hotplug, cleanups, uaccess, migration, gup, pagemap),
- various other subsystems (alpha, misc, sparse, bitmap, lib, bitops,
checkpatch, autofs, minix, nilfs, ufs, fat, signals, kmod, coredump,
exec, kdump, rapidio, panic, kcov, kgdb, ipc).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (164 commits)
mm/gup: remove task_struct pointer for all gup code
mm: clean up the last pieces of page fault accountings
mm/xtensa: use general page fault accounting
mm/x86: use general page fault accounting
mm/sparc64: use general page fault accounting
mm/sparc32: use general page fault accounting
mm/sh: use general page fault accounting
mm/s390: use general page fault accounting
mm/riscv: use general page fault accounting
mm/powerpc: use general page fault accounting
mm/parisc: use general page fault accounting
mm/openrisc: use general page fault accounting
mm/nios2: use general page fault accounting
mm/nds32: use general page fault accounting
mm/mips: use general page fault accounting
mm/microblaze: use general page fault accounting
mm/m68k: use general page fault accounting
mm/ia64: use general page fault accounting
mm/hexagon: use general page fault accounting
mm/csky: use general page fault accounting
...
After the cleanup of page fault accounting, gup does not need to pass
task_struct around any more. Remove that parameter in the whole gup
stack.
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix sparse build warnings:
kernel/kcov.c:99:1: warning:
symbol '__pcpu_scope_kcov_percpu_data' was not declared. Should it be static?
kernel/kcov.c:778:6: warning:
symbol 'kcov_remote_softirq_start' was not declared. Should it be static?
kernel/kcov.c:795:6: warning:
symbol 'kcov_remote_softirq_stop' was not declared. Should it be static?
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Wei Yongjun <weiyongjun1@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Link: http://lkml.kernel.org/r/20200702115501.73077-1-weiyongjun1@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Unconditionally add -fno-stack-protector to KCOV's compiler options, as
all supported compilers support the option. This saves a compiler
invocation to determine if the option is supported.
Because Clang does not support -fno-conserve-stack, and
-fno-stack-protector was wrapped in the same cc-option, we were missing
-fno-stack-protector with Clang. Unconditionally adding this option
fixes this for Clang.
Suggested-by: Nick Desaulniers <ndesaulniers@google.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Nick Desaulniers <ndesaulniers@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Alexander Potapenko <glider@google.com>
Link: http://lkml.kernel.org/r/20200615184302.7591-1-elver@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Since print_oops_end_marker() is not used externally, also remove it in
kernel.h at the same time.
Signed-off-by: Yue Hu <huyue2@yulong.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Kees Cook <keescook@chromium.org>
Link: http://lkml.kernel.org/r/20200724011516.12756-1-zbestahu@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The return value of oops_may_print() is true or false, so change its type
to reflect that.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Xuefeng Li <lixuefeng@loongson.cn>
Link: http://lkml.kernel.org/r/1591103358-32087-1-git-send-email-yangtiezhu@loongson.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Make kernel GNU build-id available in VMCOREINFO. Having build-id in
VMCOREINFO facilitates presenting appropriate kernel namelist image with
debug information file to kernel crash dump analysis tools. Currently
VMCOREINFO lacks uniquely identifiable key for crash analysis automation.
Regarding if this patch is necessary or matching of linux_banner and
OSRELEASE in VMCOREINFO employed by crash(8) meets the need -- IMO,
build-id approach more foolproof, in most instances it is a cryptographic
hash generated using internal code/ELF bits unlike kernel version string
upon which linux_banner is based that is external to the code. I feel
each is intended for a different purpose. Also OSRELEASE is not suitable
when two different kernel builds from same version with different features
enabled.
Currently for most linux (and non-linux) systems build-id can be extracted
using standard methods for file types such as user mode crash dumps,
shared libraries, loadable kernel modules etc., This is an exception for
linux kernel dump. Having build-id in VMCOREINFO brings some uniformity
for automation tools.
Tyler said:
: I think this is a nice improvement over today's linux_banner approach for
: correlating vmlinux to a kernel dump.
:
: The elf notes parsing in this patch lines up with what is described in in
: the "Notes (Nhdr)" section of the elf(5) man page.
:
: BUILD_ID_MAX is sufficient to hold a sha1 build-id, which is the default
: build-id type today in GNU ld(2). It is also sufficient to hold the
: "fast" build-id, which is the default build-id type today in LLVM lld(2).
Signed-off-by: Vijay Balakrishna <vijayb@linux.microsoft.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Acked-by: Baoquan He <bhe@redhat.com>
Cc: Dave Young <dyoung@redhat.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Link: http://lkml.kernel.org/r/1591849672-34104-1-git-send-email-vijayb@linux.microsoft.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
There exists redundant "be an" in the comment, remove it.
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Luis Chamberlain <mcgrof@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Chuck Lever <chuck.lever@oracle.com>
Cc: David Howells <dhowells@redhat.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: James Morris <jmorris@namei.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: J. Bruce Fields <bfields@fieldses.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Lars Ellenberg <lars.ellenberg@linbit.com>
Cc: Nikolay Aleksandrov <nikolay@cumulusnetworks.com>
Cc: Philipp Reisner <philipp.reisner@linbit.com>
Cc: Roopa Prabhu <roopa@cumulusnetworks.com>
Cc: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Sergei Trofimovich <slyfox@gentoo.org>
Cc: Sergey Kvachonok <ravenexp@gmail.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Tony Vroon <chainsaw@gentoo.org>
Cc: Christoph Hellwig <hch@infradead.org>
Link: http://lkml.kernel.org/r/20200610154923.27510-3-mcgrof@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add a helper that waits for a pid and stores the status in the passed in
kernel pointer. Use it to fix the usage of kernel_wait4 in
call_usermodehelper_exec_sync that only happens to work due to the
implicit set_fs(KERNEL_DS) for kernel threads.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Link: http://lkml.kernel.org/r/20200721130449.5008-1-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Both exec and exit want to ensure that the uaccess routines actually do
access user pointers. Use the newly added force_uaccess_begin helper
instead of an open coded set_fs for that to prepare for kernel builds
where set_fs() does not exist.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Greentime Hu <green.hu@gmail.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Link: http://lkml.kernel.org/r/20200710135706.537715-7-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add helpers to wrap the get_fs/set_fs magic for undoing any damange done
by set_fs(KERNEL_DS). There is no real functional benefit, but this
documents the intent of these calls better, and will allow stubbing the
functions out easily for kernels builds that do not allow address space
overrides in the future.
[hch@lst.de: drop two incorrect hunks, fix a commit log typo]
Link: http://lkml.kernel.org/r/20200714105505.935079-6-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Nick Hu <nickhu@andestech.com>
Cc: Vincent Chen <deanbo422@gmail.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Link: http://lkml.kernel.org/r/20200710135706.537715-6-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Proactive compaction uses per-node/zone "fragmentation score" which is
always in range [0, 100], so use unsigned type of these scores as well as
for related constants.
Signed-off-by: Nitin Gupta <nigupta@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Baoquan He <bhe@redhat.com>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Link: http://lkml.kernel.org/r/20200618010319.13159-1-nigupta@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For some applications, we need to allocate almost all memory as hugepages.
However, on a running system, higher-order allocations can fail if the
memory is fragmented. Linux kernel currently does on-demand compaction as
we request more hugepages, but this style of compaction incurs very high
latency. Experiments with one-time full memory compaction (followed by
hugepage allocations) show that kernel is able to restore a highly
fragmented memory state to a fairly compacted memory state within <1 sec
for a 32G system. Such data suggests that a more proactive compaction can
help us allocate a large fraction of memory as hugepages keeping
allocation latencies low.
For a more proactive compaction, the approach taken here is to define a
new sysctl called 'vm.compaction_proactiveness' which dictates bounds for
external fragmentation which kcompactd tries to maintain.
The tunable takes a value in range [0, 100], with a default of 20.
Note that a previous version of this patch [1] was found to introduce too
many tunables (per-order extfrag{low, high}), but this one reduces them to
just one sysctl. Also, the new tunable is an opaque value instead of
asking for specific bounds of "external fragmentation", which would have
been difficult to estimate. The internal interpretation of this opaque
value allows for future fine-tuning.
Currently, we use a simple translation from this tunable to [low, high]
"fragmentation score" thresholds (low=100-proactiveness, high=low+10%).
The score for a node is defined as weighted mean of per-zone external
fragmentation. A zone's present_pages determines its weight.
To periodically check per-node score, we reuse per-node kcompactd threads,
which are woken up every 500 milliseconds to check the same. If a node's
score exceeds its high threshold (as derived from user-provided
proactiveness value), proactive compaction is started until its score
reaches its low threshold value. By default, proactiveness is set to 20,
which implies threshold values of low=80 and high=90.
This patch is largely based on ideas from Michal Hocko [2]. See also the
LWN article [3].
Performance data
================
System: x64_64, 1T RAM, 80 CPU threads.
Kernel: 5.6.0-rc3 + this patch
echo madvise | sudo tee /sys/kernel/mm/transparent_hugepage/enabled
echo madvise | sudo tee /sys/kernel/mm/transparent_hugepage/defrag
Before starting the driver, the system was fragmented from a userspace
program that allocates all memory and then for each 2M aligned section,
frees 3/4 of base pages using munmap. The workload is mainly anonymous
userspace pages, which are easy to move around. I intentionally avoided
unmovable pages in this test to see how much latency we incur when
hugepage allocations hit direct compaction.
1. Kernel hugepage allocation latencies
With the system in such a fragmented state, a kernel driver then allocates
as many hugepages as possible and measures allocation latency:
(all latency values are in microseconds)
- With vanilla 5.6.0-rc3
percentile latency
–––––––––– –––––––
5 7894
10 9496
25 12561
30 15295
40 18244
50 21229
60 27556
75 30147
80 31047
90 32859
95 33799
Total 2M hugepages allocated = 383859 (749G worth of hugepages out of 762G
total free => 98% of free memory could be allocated as hugepages)
- With 5.6.0-rc3 + this patch, with proactiveness=20
sysctl -w vm.compaction_proactiveness=20
percentile latency
–––––––––– –––––––
5 2
10 2
25 3
30 3
40 3
50 4
60 4
75 4
80 4
90 5
95 429
Total 2M hugepages allocated = 384105 (750G worth of hugepages out of 762G
total free => 98% of free memory could be allocated as hugepages)
2. JAVA heap allocation
In this test, we first fragment memory using the same method as for (1).
Then, we start a Java process with a heap size set to 700G and request the
heap to be allocated with THP hugepages. We also set THP to madvise to
allow hugepage backing of this heap.
/usr/bin/time
java -Xms700G -Xmx700G -XX:+UseTransparentHugePages -XX:+AlwaysPreTouch
The above command allocates 700G of Java heap using hugepages.
- With vanilla 5.6.0-rc3
17.39user 1666.48system 27:37.89elapsed
- With 5.6.0-rc3 + this patch, with proactiveness=20
8.35user 194.58system 3:19.62elapsed
Elapsed time remains around 3:15, as proactiveness is further increased.
Note that proactive compaction happens throughout the runtime of these
workloads. The situation of one-time compaction, sufficient to supply
hugepages for following allocation stream, can probably happen for more
extreme proactiveness values, like 80 or 90.
In the above Java workload, proactiveness is set to 20. The test starts
with a node's score of 80 or higher, depending on the delay between the
fragmentation step and starting the benchmark, which gives more-or-less
time for the initial round of compaction. As t he benchmark consumes
hugepages, node's score quickly rises above the high threshold (90) and
proactive compaction starts again, which brings down the score to the low
threshold level (80). Repeat.
bpftrace also confirms proactive compaction running 20+ times during the
runtime of this Java benchmark. kcompactd threads consume 100% of one of
the CPUs while it tries to bring a node's score within thresholds.
Backoff behavior
================
Above workloads produce a memory state which is easy to compact. However,
if memory is filled with unmovable pages, proactive compaction should
essentially back off. To test this aspect:
- Created a kernel driver that allocates almost all memory as hugepages
followed by freeing first 3/4 of each hugepage.
- Set proactiveness=40
- Note that proactive_compact_node() is deferred maximum number of times
with HPAGE_FRAG_CHECK_INTERVAL_MSEC of wait between each check
(=> ~30 seconds between retries).
[1] https://patchwork.kernel.org/patch/11098289/
[2] https://lore.kernel.org/linux-mm/20161230131412.GI13301@dhcp22.suse.cz/
[3] https://lwn.net/Articles/817905/
Signed-off-by: Nitin Gupta <nigupta@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Oleksandr Natalenko <oleksandr@redhat.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Reviewed-by: Oleksandr Natalenko <oleksandr@redhat.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Nitin Gupta <ngupta@nitingupta.dev>
Cc: Oleksandr Natalenko <oleksandr@redhat.com>
Link: http://lkml.kernel.org/r/20200616204527.19185-1-nigupta@nvidia.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In current implementation, newly created or swap-in anonymous page is
started on active list. Growing active list results in rebalancing
active/inactive list so old pages on active list are demoted to inactive
list. Hence, the page on active list isn't protected at all.
Following is an example of this situation.
Assume that 50 hot pages on active list. Numbers denote the number of
pages on active/inactive list (active | inactive).
1. 50 hot pages on active list
50(h) | 0
2. workload: 50 newly created (used-once) pages
50(uo) | 50(h)
3. workload: another 50 newly created (used-once) pages
50(uo) | 50(uo), swap-out 50(h)
This patch tries to fix this issue. Like as file LRU, newly created or
swap-in anonymous pages will be inserted to the inactive list. They are
promoted to active list if enough reference happens. This simple
modification changes the above example as following.
1. 50 hot pages on active list
50(h) | 0
2. workload: 50 newly created (used-once) pages
50(h) | 50(uo)
3. workload: another 50 newly created (used-once) pages
50(h) | 50(uo), swap-out 50(uo)
As you can see, hot pages on active list would be protected.
Note that, this implementation has a drawback that the page cannot be
promoted and will be swapped-out if re-access interval is greater than the
size of inactive list but less than the size of total(active+inactive).
To solve this potential issue, following patch will apply workingset
detection similar to the one that's already applied to file LRU.
Signed-off-by: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Johannes Weiner <hannes@cmpxchg.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Hugh Dickins <hughd@google.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Minchan Kim <minchan@kernel.org>
Link: http://lkml.kernel.org/r/1595490560-15117-3-git-send-email-iamjoonsoo.kim@lge.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
rearm_wake_irq() does not unlock the irq descriptor if the interrupt
is not suspended or if wakeup is not enabled on it.
Restucture the exit conditions so the unlock is always ensured.
Fixes: 3a79bc63d9 ("PCI: irq: Introduce rearm_wake_irq()")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200811180001.80203-1-linux@roeck-us.net
- Add 'Runtime Firmware Activation' support for NVDIMMs that advertise
the relevant capability
- Misc libnvdimm and DAX cleanups
-----BEGIN PGP SIGNATURE-----
iHUEABYIAB0WIQT9vPEBxh63bwxRYEEPzq5USduLdgUCXzHodgAKCRAPzq5USduL
djTjAQD1THDmizHn16zd94ueygh/BXfN0zyeVvQH352ol7kdfQEAj2A7YJ9XBbBY
JC6/CNd+OiB9W88lLOUf3Waj1a7cUQ8=
=Q6qn
-----END PGP SIGNATURE-----
Merge tag 'libnvdimm-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm
Pull libnvdimm updayes from Vishal Verma:
"You'd normally receive this pull request from Dan Williams, but he's
busy watching a newborn (Congrats Dan!), so I'm watching libnvdimm
this cycle.
This adds a new feature in libnvdimm - 'Runtime Firmware Activation',
and a few small cleanups and fixes in libnvdimm and DAX. I'd
originally intended to make separate topic-based pull requests - one
for libnvdimm, and one for DAX, but some of the DAX material fell out
since it wasn't quite ready.
Summary:
- add 'Runtime Firmware Activation' support for NVDIMMs that
advertise the relevant capability
- misc libnvdimm and DAX cleanups"
* tag 'libnvdimm-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/nvdimm/nvdimm:
libnvdimm/security: ensure sysfs poll thread woke up and fetch updated attr
libnvdimm/security: the 'security' attr never show 'overwrite' state
libnvdimm/security: fix a typo
ACPI: NFIT: Fix ARS zero-sized allocation
dax: Fix incorrect argument passed to xas_set_err()
ACPI: NFIT: Add runtime firmware activate support
PM, libnvdimm: Add runtime firmware activation support
libnvdimm: Convert to DEVICE_ATTR_ADMIN_RO()
drivers/dax: Expand lock scope to cover the use of addresses
fs/dax: Remove unused size parameter
dax: print error message by pr_info() in __generic_fsdax_supported()
driver-core: Introduce DEVICE_ATTR_ADMIN_{RO,RW}
tools/testing/nvdimm: Emulate firmware activation commands
tools/testing/nvdimm: Prepare nfit_ctl_test() for ND_CMD_CALL emulation
tools/testing/nvdimm: Add command debug messages
tools/testing/nvdimm: Cleanup dimm index passing
ACPI: NFIT: Define runtime firmware activation commands
ACPI: NFIT: Move bus_dsm_mask out of generic nvdimm_bus_descriptor
libnvdimm: Validate command family indices
- Untangle the header spaghetti which causes build failures in various
situations caused by the lockdep additions to seqcount to validate that
the write side critical sections are non-preemptible.
- The seqcount associated lock debug addons which were blocked by the
above fallout.
seqcount writers contrary to seqlock writers must be externally
serialized, which usually happens via locking - except for strict per
CPU seqcounts. As the lock is not part of the seqcount, lockdep cannot
validate that the lock is held.
This new debug mechanism adds the concept of associated locks.
sequence count has now lock type variants and corresponding
initializers which take a pointer to the associated lock used for
writer serialization. If lockdep is enabled the pointer is stored and
write_seqcount_begin() has a lockdep assertion to validate that the
lock is held.
Aside of the type and the initializer no other code changes are
required at the seqcount usage sites. The rest of the seqcount API is
unchanged and determines the type at compile time with the help of
_Generic which is possible now that the minimal GCC version has been
moved up.
Adding this lockdep coverage unearthed a handful of seqcount bugs which
have been addressed already independent of this.
While generaly useful this comes with a Trojan Horse twist: On RT
kernels the write side critical section can become preemtible if the
writers are serialized by an associated lock, which leads to the well
known reader preempts writer livelock. RT prevents this by storing the
associated lock pointer independent of lockdep in the seqcount and
changing the reader side to block on the lock when a reader detects
that a writer is in the write side critical section.
- Conversion of seqcount usage sites to associated types and initializers.
-----BEGIN PGP SIGNATURE-----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=7Gj+
-----END PGP SIGNATURE-----
Merge tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Thomas Gleixner:
"A set of locking fixes and updates:
- Untangle the header spaghetti which causes build failures in
various situations caused by the lockdep additions to seqcount to
validate that the write side critical sections are non-preemptible.
- The seqcount associated lock debug addons which were blocked by the
above fallout.
seqcount writers contrary to seqlock writers must be externally
serialized, which usually happens via locking - except for strict
per CPU seqcounts. As the lock is not part of the seqcount, lockdep
cannot validate that the lock is held.
This new debug mechanism adds the concept of associated locks.
sequence count has now lock type variants and corresponding
initializers which take a pointer to the associated lock used for
writer serialization. If lockdep is enabled the pointer is stored
and write_seqcount_begin() has a lockdep assertion to validate that
the lock is held.
Aside of the type and the initializer no other code changes are
required at the seqcount usage sites. The rest of the seqcount API
is unchanged and determines the type at compile time with the help
of _Generic which is possible now that the minimal GCC version has
been moved up.
Adding this lockdep coverage unearthed a handful of seqcount bugs
which have been addressed already independent of this.
While generally useful this comes with a Trojan Horse twist: On RT
kernels the write side critical section can become preemtible if
the writers are serialized by an associated lock, which leads to
the well known reader preempts writer livelock. RT prevents this by
storing the associated lock pointer independent of lockdep in the
seqcount and changing the reader side to block on the lock when a
reader detects that a writer is in the write side critical section.
- Conversion of seqcount usage sites to associated types and
initializers"
* tag 'locking-urgent-2020-08-10' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
locking/seqlock, headers: Untangle the spaghetti monster
locking, arch/ia64: Reduce <asm/smp.h> header dependencies by moving XTP bits into the new <asm/xtp.h> header
x86/headers: Remove APIC headers from <asm/smp.h>
seqcount: More consistent seqprop names
seqcount: Compress SEQCNT_LOCKNAME_ZERO()
seqlock: Fold seqcount_LOCKNAME_init() definition
seqlock: Fold seqcount_LOCKNAME_t definition
seqlock: s/__SEQ_LOCKDEP/__SEQ_LOCK/g
hrtimer: Use sequence counter with associated raw spinlock
kvm/eventfd: Use sequence counter with associated spinlock
userfaultfd: Use sequence counter with associated spinlock
NFSv4: Use sequence counter with associated spinlock
iocost: Use sequence counter with associated spinlock
raid5: Use sequence counter with associated spinlock
vfs: Use sequence counter with associated spinlock
timekeeping: Use sequence counter with associated raw spinlock
xfrm: policy: Use sequence counters with associated lock
netfilter: nft_set_rbtree: Use sequence counter with associated rwlock
netfilter: conntrack: Use sequence counter with associated spinlock
sched: tasks: Use sequence counter with associated spinlock
...
Drop repeated words in kernel/time/. {when, one, into}
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: John Stultz <john.stultz@linaro.org>
Link: https://lore.kernel.org/r/20200807033248.8452-1-rdunlap@infradead.org
- run the checker (e.g. sparse) after the compiler
- remove unneeded cc-option tests for old compiler flags
- fix tar-pkg to install dtbs
- introduce ccflags-remove-y and asflags-remove-y syntax
- allow to trace functions in sub-directories of lib/
- introduce hostprogs-always-y and userprogs-always-y syntax
- various Makefile cleanups
-----BEGIN PGP SIGNATURE-----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=bkNQ
-----END PGP SIGNATURE-----
Merge tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- run the checker (e.g. sparse) after the compiler
- remove unneeded cc-option tests for old compiler flags
- fix tar-pkg to install dtbs
- introduce ccflags-remove-y and asflags-remove-y syntax
- allow to trace functions in sub-directories of lib/
- introduce hostprogs-always-y and userprogs-always-y syntax
- various Makefile cleanups
* tag 'kbuild-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
kbuild: stop filtering out $(GCC_PLUGINS_CFLAGS) from cc-option base
kbuild: include scripts/Makefile.* only when relevant CONFIG is enabled
kbuild: introduce hostprogs-always-y and userprogs-always-y
kbuild: sort hostprogs before passing it to ifneq
kbuild: move host .so build rules to scripts/gcc-plugins/Makefile
kbuild: Replace HTTP links with HTTPS ones
kbuild: trace functions in subdirectories of lib/
kbuild: introduce ccflags-remove-y and asflags-remove-y
kbuild: do not export LDFLAGS_vmlinux
kbuild: always create directories of targets
powerpc/boot: add DTB to 'targets'
kbuild: buildtar: add dtbs support
kbuild: remove cc-option test of -ffreestanding
kbuild: remove cc-option test of -fno-stack-protector
Revert "kbuild: Create directory for target DTB"
kbuild: run the checker after the compiler
CFLAGS_REMOVE_<file>.o filters out flags when compiling a particular
object, but there is no convenient way to do that for every object in
a directory.
Add ccflags-remove-y and asflags-remove-y to make it easily.
Use ccflags-remove-y to clean up some Makefiles.
The add/remove order works as follows:
[1] KBUILD_CFLAGS specifies compiler flags used globally
[2] ccflags-y adds compiler flags for all objects in the
current Makefile
[3] ccflags-remove-y removes compiler flags for all objects in the
current Makefile (New feature)
[4] CFLAGS_<file> adds compiler flags per file.
[5] CFLAGS_REMOVE_<file> removes compiler flags per file.
Having [3] before [4] allows us to remove flags from most (but not all)
objects in the current Makefile.
For example, kernel/trace/Makefile removes $(CC_FLAGS_FTRACE)
from all objects in the directory, then adds it back to
trace_selftest_dynamic.o and CFLAGS_trace_kprobe_selftest.o
The same applies to lib/livepatch/Makefile.
Please note ccflags-remove-y has no effect to the sub-directories.
In contrast, the previous notation got rid of compiler flags also from
all the sub-directories.
The following are not affected because they have no sub-directories:
arch/arm/boot/compressed/
arch/powerpc/xmon/
arch/sh/
kernel/trace/
However, lib/ has several sub-directories.
To keep the behavior, I added ccflags-remove-y to all Makefiles
in subdirectories of lib/, except the following:
lib/vdso/Makefile - Kbuild does not descend into this Makefile
lib/raid/test/Makefile - This is not used for the kernel build
I think commit 2464a609de ("ftrace: do not trace library functions")
excluded too much. In the next commit, I will remove ccflags-remove-y
from the sub-directories of lib/.
Suggested-by: Sami Tolvanen <samitolvanen@google.com>
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Acked-by: Michael Ellerman <mpe@ellerman.id.au> (powerpc)
Acked-by: Brendan Higgins <brendanhiggins@google.com> (KUnit)
Tested-by: Anders Roxell <anders.roxell@linaro.org>
- The biggest news in that the tracing ring buffer can now time events that
interrupted other ring buffer events. Before this change, if an interrupt
came in while recording another event, and that interrupt also had an
event, those events would all have the same time stamp as the event it
interrupted. Now, with the new design, those events will have a unique time
stamp and rightfully display the time for those events that were recorded
while interrupting another event.
- Bootconfig how has an "override" operator that lets the users have a
default config, but then add options to override the default.
- A fix was made to properly filter function graph tracing to the ftrace
PIDs. This came in at the end of the -rc cycle, and needs to be backported.
- Several clean ups, performance updates, and minor fixes as well.
-----BEGIN PGP SIGNATURE-----
iIoEABYIADIWIQRRSw7ePDh/lE+zeZMp5XQQmuv6qgUCXy3GOBQccm9zdGVkdEBn
b29kbWlzLm9yZwAKCRAp5XQQmuv6qphsAP9ci1jtrC2+cMBMCNKb/AFpA/nDaKsD
hpsDzvD0YPOmCAEA9QbZset8wUNG49R4FexP7egQ8Ad2S6Oa5f60jWleDQY=
=lH+q
-----END PGP SIGNATURE-----
Merge tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- The biggest news in that the tracing ring buffer can now time events
that interrupted other ring buffer events.
Before this change, if an interrupt came in while recording another
event, and that interrupt also had an event, those events would all
have the same time stamp as the event it interrupted.
Now, with the new design, those events will have a unique time stamp
and rightfully display the time for those events that were recorded
while interrupting another event.
- Bootconfig how has an "override" operator that lets the users have a
default config, but then add options to override the default.
- A fix was made to properly filter function graph tracing to the
ftrace PIDs. This came in at the end of the -rc cycle, and needs to
be backported.
- Several clean ups, performance updates, and minor fixes as well.
* tag 'trace-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (39 commits)
tracing: Add trace_array_init_printk() to initialize instance trace_printk() buffers
kprobes: Fix compiler warning for !CONFIG_KPROBES_ON_FTRACE
tracing: Use trace_sched_process_free() instead of exit() for pid tracing
bootconfig: Fix to find the initargs correctly
Documentation: bootconfig: Add bootconfig override operator
tools/bootconfig: Add testcases for value override operator
lib/bootconfig: Add override operator support
kprobes: Remove show_registers() function prototype
tracing/uprobe: Remove dead code in trace_uprobe_register()
kprobes: Fix NULL pointer dereference at kprobe_ftrace_handler
ftrace: Fix ftrace_trace_task return value
tracepoint: Use __used attribute definitions from compiler_attributes.h
tracepoint: Mark __tracepoint_string's __used
trace : Have tracing buffer info use kvzalloc instead of kzalloc
tracing: Remove outdated comment in stack handling
ftrace: Do not let direct or IPMODIFY ftrace_ops be added to module and set trampolines
ftrace: Setup correct FTRACE_FL_REGS flags for module
tracing/hwlat: Honor the tracing_cpumask
tracing/hwlat: Drop the duplicate assignment in start_kthread()
tracing: Save one trace_event->type by using __TRACE_LAST_TYPE
...
As trace_array_printk() used with not global instances will not add noise to
the main buffer, they are OK to have in the kernel (unlike trace_printk()).
This require the subsystem to create their own tracing instance, and the
trace_array_printk() only writes into those instances.
Add trace_array_init_printk() to initialize the trace_printk() buffers
without printing out the WARNING message.
Reported-by: Sean Paul <sean@poorly.run>
Reviewed-by: Sean Paul <sean@poorly.run>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----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=MRuJ
-----END PGP SIGNATURE-----
Merge tag 'kallsyms_show_value-fix-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull sysfs module section fix from Kees Cook:
"Fix sysfs module section output overflow.
About a month after my kallsyms_show_value() refactoring landed, 0day
noticed that there was a path through the kernfs binattr read handlers
that did not have PAGE_SIZEd buffers, and the module "sections" read
handler made a bad assumption about this, resulting in it stomping on
memory when reached through small-sized splice() calls.
I've added a set of tests to find these kinds of regressions more
quickly in the future as well"
Sefltests-acked-by: Shuah Khan <skhan@linuxfoundation.org>
* tag 'kallsyms_show_value-fix-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests: splice: Check behavior of full and short splices
module: Correctly truncate sysfs sections output
Merge misc updates from Andrew Morton:
- a few MM hotfixes
- kthread, tools, scripts, ntfs and ocfs2
- some of MM
Subsystems affected by this patch series: kthread, tools, scripts, ntfs,
ocfs2 and mm (hofixes, pagealloc, slab-generic, slab, slub, kcsan,
debug, pagecache, gup, swap, shmem, memcg, pagemap, mremap, mincore,
sparsemem, vmalloc, kasan, pagealloc, hugetlb and vmscan).
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (162 commits)
mm: vmscan: consistent update to pgrefill
mm/vmscan.c: fix typo
khugepaged: khugepaged_test_exit() check mmget_still_valid()
khugepaged: retract_page_tables() remember to test exit
khugepaged: collapse_pte_mapped_thp() protect the pmd lock
khugepaged: collapse_pte_mapped_thp() flush the right range
mm/hugetlb: fix calculation of adjust_range_if_pmd_sharing_possible
mm: thp: replace HTTP links with HTTPS ones
mm/page_alloc: fix memalloc_nocma_{save/restore} APIs
mm/page_alloc.c: skip setting nodemask when we are in interrupt
mm/page_alloc: fallbacks at most has 3 elements
mm/page_alloc: silence a KASAN false positive
mm/page_alloc.c: remove unnecessary end_bitidx for [set|get]_pfnblock_flags_mask()
mm/page_alloc.c: simplify pageblock bitmap access
mm/page_alloc.c: extract the common part in pfn_to_bitidx()
mm/page_alloc.c: replace the definition of NR_MIGRATETYPE_BITS with PB_migratetype_bits
mm/shuffle: remove dynamic reconfiguration
mm/memory_hotplug: document why shuffle_zone() is relevant
mm/page_alloc: remove nr_free_pagecache_pages()
mm: remove vm_total_pages
...
Patch series "kasan: memorize and print call_rcu stack", v8.
This patchset improves KASAN reports by making them to have call_rcu()
call stack information. It is useful for programmers to solve
use-after-free or double-free memory issue.
The KASAN report was as follows(cleaned up slightly):
BUG: KASAN: use-after-free in kasan_rcu_reclaim+0x58/0x60
Freed by task 0:
kasan_save_stack+0x24/0x50
kasan_set_track+0x24/0x38
kasan_set_free_info+0x18/0x20
__kasan_slab_free+0x10c/0x170
kasan_slab_free+0x10/0x18
kfree+0x98/0x270
kasan_rcu_reclaim+0x1c/0x60
Last call_rcu():
kasan_save_stack+0x24/0x50
kasan_record_aux_stack+0xbc/0xd0
call_rcu+0x8c/0x580
kasan_rcu_uaf+0xf4/0xf8
Generic KASAN will record the last two call_rcu() call stacks and print up
to 2 call_rcu() call stacks in KASAN report. it is only suitable for
generic KASAN.
This feature considers the size of struct kasan_alloc_meta and
kasan_free_meta, we try to optimize the structure layout and size, lets it
get better memory consumption.
[1]https://bugzilla.kernel.org/show_bug.cgi?id=198437
[2]https://groups.google.com/forum/#!searchin/kasan-dev/better$20stack$20traces$20for$20rcu%7Csort:date/kasan-dev/KQsjT_88hDE/7rNUZprRBgAJ
This patch (of 4):
This feature will record the last two call_rcu() call stacks and prints up
to 2 call_rcu() call stacks in KASAN report.
When call_rcu() is called, we store the call_rcu() call stack into slub
alloc meta-data, so that the KASAN report can print rcu stack.
[1]https://bugzilla.kernel.org/show_bug.cgi?id=198437
[2]https://groups.google.com/forum/#!searchin/kasan-dev/better$20stack$20traces$20for$20rcu%7Csort:date/kasan-dev/KQsjT_88hDE/7rNUZprRBgAJ
[walter-zh.wu@mediatek.com: build fix]
Link: http://lkml.kernel.org/r/20200710162401.23816-1-walter-zh.wu@mediatek.com
Suggested-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Walter Wu <walter-zh.wu@mediatek.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Dmitry Vyukov <dvyukov@google.com>
Reviewed-by: Andrey Konovalov <andreyknvl@google.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Josh Triplett <josh@joshtriplett.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Lai Jiangshan <jiangshanlai@gmail.com>
Cc: Joel Fernandes <joel@joelfernandes.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Matthias Brugger <matthias.bgg@gmail.com>
Link: http://lkml.kernel.org/r/20200710162123.23713-1-walter-zh.wu@mediatek.com
Link: http://lkml.kernel.org/r/20200601050847.1096-1-walter-zh.wu@mediatek.com
Link: http://lkml.kernel.org/r/20200601050927.1153-1-walter-zh.wu@mediatek.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When checking a performance change for will-it-scale scalability mmap test
[1], we found very high lock contention for spinlock of percpu counter
'vm_committed_as':
94.14% 0.35% [kernel.kallsyms] [k] _raw_spin_lock_irqsave
48.21% _raw_spin_lock_irqsave;percpu_counter_add_batch;__vm_enough_memory;mmap_region;do_mmap;
45.91% _raw_spin_lock_irqsave;percpu_counter_add_batch;__do_munmap;
Actually this heavy lock contention is not always necessary. The
'vm_committed_as' needs to be very precise when the strict
OVERCOMMIT_NEVER policy is set, which requires a rather small batch number
for the percpu counter.
So keep 'batch' number unchanged for strict OVERCOMMIT_NEVER policy, and
lift it to 64X for OVERCOMMIT_ALWAYS and OVERCOMMIT_GUESS policies. Also
add a sysctl handler to adjust it when the policy is reconfigured.
Benchmark with the same testcase in [1] shows 53% improvement on a 8C/16T
desktop, and 2097%(20X) on a 4S/72C/144T server. We tested with test
platforms in 0day (server, desktop and laptop), and 80%+ platforms shows
improvements with that test. And whether it shows improvements depends on
if the test mmap size is bigger than the batch number computed.
And if the lift is 16X, 1/3 of the platforms will show improvements,
though it should help the mmap/unmap usage generally, as Michal Hocko
mentioned:
: I believe that there are non-synthetic worklaods which would benefit from
: a larger batch. E.g. large in memory databases which do large mmaps
: during startups from multiple threads.
[1] https://lore.kernel.org/lkml/20200305062138.GI5972@shao2-debian/
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Qian Cai <cai@lca.pw>
Cc: Kees Cook <keescook@chromium.org>
Cc: Andi Kleen <andi.kleen@intel.com>
Cc: Tim Chen <tim.c.chen@intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Dennis Zhou <dennis@kernel.org>
Cc: Haiyang Zhang <haiyangz@microsoft.com>
Cc: kernel test robot <rong.a.chen@intel.com>
Cc: "K. Y. Srinivasan" <kys@microsoft.com>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1589611660-89854-4-git-send-email-feng.tang@intel.com
Link: http://lkml.kernel.org/r/1592725000-73486-4-git-send-email-feng.tang@intel.com
Link: http://lkml.kernel.org/r/1594389708-60781-5-git-send-email-feng.tang@intel.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently the kernel stack is being accounted per-zone. There is no need
to do that. In addition due to being per-zone, memcg has to keep a
separate MEMCG_KERNEL_STACK_KB. Make the stat per-node and deprecate
MEMCG_KERNEL_STACK_KB as memcg_stat_item is an extension of
node_stat_item. In addition localize the kernel stack stats updates to
account_kernel_stack().
Signed-off-by: Shakeel Butt <shakeelb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@kernel.org>
Link: http://lkml.kernel.org/r/20200630161539.1759185-1-shakeelb@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In order to prepare for per-object slab memory accounting, convert
NR_SLAB_RECLAIMABLE and NR_SLAB_UNRECLAIMABLE vmstat items to bytes.
To make it obvious, rename them to NR_SLAB_RECLAIMABLE_B and
NR_SLAB_UNRECLAIMABLE_B (similar to NR_KERNEL_STACK_KB).
Internally global and per-node counters are stored in pages, however memcg
and lruvec counters are stored in bytes. This scheme may look weird, but
only for now. As soon as slab pages will be shared between multiple
cgroups, global and node counters will reflect the total number of slab
pages. However memcg and lruvec counters will be used for per-memcg slab
memory tracking, which will take separate kernel objects in the account.
Keeping global and node counters in pages helps to avoid additional
overhead.
The size of slab memory shouldn't exceed 4Gb on 32-bit machines, so it
will fit into atomic_long_t we use for vmstats.
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>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Christoph Lameter <cl@linux.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/20200623174037.3951353-4-guro@fb.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Originally kthread_create_on_cpu() parked and woke up the new thread.
However, since commit a65d40961d ("kthread/smpboot: do not park in
kthread_create_on_cpu()") this is no longer the case. This patch removes
the comment that has been left behind and is now incorrect / stale.
Fixes: a65d40961d ("kthread/smpboot: do not park in kthread_create_on_cpu()")
Signed-off-by: Ilias Stamatis <stamatis.iliass@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Link: http://lkml.kernel.org/r/20200611135920.240551-1-stamatis.iliass@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
For SMP systems using IPI based TLB invalidation, looking at
current->active_mm is entirely reasonable. This then presents the
following race condition:
CPU0 CPU1
flush_tlb_mm(mm) use_mm(mm)
<send-IPI>
tsk->active_mm = mm;
<IPI>
if (tsk->active_mm == mm)
// flush TLBs
</IPI>
switch_mm(old_mm,mm,tsk);
Where it is possible the IPI flushed the TLBs for @old_mm, not @mm,
because the IPI lands before we actually switched.
Avoid this by disabling IRQs across changing ->active_mm and
switch_mm().
Of the (SMP) architectures that have IPI based TLB invalidate:
Alpha - checks active_mm
ARC - ASID specific
IA64 - checks active_mm
MIPS - ASID specific flush
OpenRISC - shoots down world
PARISC - shoots down world
SH - ASID specific
SPARC - ASID specific
x86 - N/A
xtensa - checks active_mm
So at the very least Alpha, IA64 and Xtensa are suspect.
On top of this, for scheduler consistency we need at least preemption
disabled across changing tsk->mm and doing switch_mm(), which is
currently provided by task_lock(), but that's not sufficient for
PREEMPT_RT.
[akpm@linux-foundation.org: add comment]
Reported-by: Andy Lutomirski <luto@amacapital.net>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Jann Horn <jannh@google.com>
Cc: Will Deacon <will@kernel.org>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200721154106.GE10769@hirez.programming.kicks-ass.net
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The only-root-readable /sys/module/$module/sections/$section files
did not truncate their output to the available buffer size. While most
paths into the kernfs read handlers end up using PAGE_SIZE buffers,
it's possible to get there through other paths (e.g. splice, sendfile).
Actually limit the output to the "count" passed into the read function,
and report it back correctly. *sigh*
Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/20200805002015.GE23458@shao2-debian
Fixes: ed66f991bb ("module: Refactor section attr into bin attribute")
Cc: stable@vger.kernel.org
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
- Add support for (optionally) using queued spinlocks & rwlocks.
- Support for a new faster system call ABI using the scv instruction on Power9
or later.
- Drop support for the PROT_SAO mmap/mprotect flag as it will be unsupported on
Power10 and future processors, leaving us with no way to implement the
functionality it requests. This risks breaking userspace, though we believe
it is unused in practice.
- A bug fix for, and then the removal of, our custom stack expansion checking.
We now allow stack expansion up to the rlimit, like other architectures.
- Remove the remnants of our (previously disabled) topology update code, which
tried to react to NUMA layout changes on virtualised systems, but was prone
to crashes and other problems.
- Add PMU support for Power10 CPUs.
- A change to our signal trampoline so that we don't unbalance the link stack
(branch return predictor) in the signal delivery path.
- Lots of other cleanups, refactorings, smaller features and so on as usual.
Thanks to:
Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey Kardashevskiy,
Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju T Sudhakar, Anton
Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan S, Bharata B Rao, Bill
Wendling, Bin Meng, Cédric Le Goater, Chris Packham, Christophe Leroy,
Christoph Hellwig, Daniel Axtens, Dan Williams, David Lamparter, Desnes A.
Nunes do Rosario, Erhard F., Finn Thain, Frederic Barrat, Ganesh Goudar,
Gautham R. Shenoy, Geoff Levand, Greg Kurz, Gustavo A. R. Silva, Hari Bathini,
Harish, Imre Kaloz, Joel Stanley, Joe Perches, John Crispin, Jordan Niethe,
Kajol Jain, Kamalesh Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li
RongQing, Madhavan Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal
Suchanek, Milton Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan
Chancellor, Nathan Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver
O'Halloran, Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe
Bergheaud, Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy
Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh
Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar Dronamraju,
Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza Cascardo, Thiago Jung
Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov, Wei Yongjun, Wen Xiong,
YueHaibing.
-----BEGIN PGP SIGNATURE-----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=QMY1
-----END PGP SIGNATURE-----
Merge tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Add support for (optionally) using queued spinlocks & rwlocks.
- Support for a new faster system call ABI using the scv instruction on
Power9 or later.
- Drop support for the PROT_SAO mmap/mprotect flag as it will be
unsupported on Power10 and future processors, leaving us with no way
to implement the functionality it requests. This risks breaking
userspace, though we believe it is unused in practice.
- A bug fix for, and then the removal of, our custom stack expansion
checking. We now allow stack expansion up to the rlimit, like other
architectures.
- Remove the remnants of our (previously disabled) topology update
code, which tried to react to NUMA layout changes on virtualised
systems, but was prone to crashes and other problems.
- Add PMU support for Power10 CPUs.
- A change to our signal trampoline so that we don't unbalance the link
stack (branch return predictor) in the signal delivery path.
- Lots of other cleanups, refactorings, smaller features and so on as
usual.
Thanks to: Abhishek Goel, Alastair D'Silva, Alexander A. Klimov, Alexey
Kardashevskiy, Alistair Popple, Andrew Donnellan, Aneesh Kumar K.V, Anju
T Sudhakar, Anton Blanchard, Arnd Bergmann, Athira Rajeev, Balamuruhan
S, Bharata B Rao, Bill Wendling, Bin Meng, Cédric Le Goater, Chris
Packham, Christophe Leroy, Christoph Hellwig, Daniel Axtens, Dan
Williams, David Lamparter, Desnes A. Nunes do Rosario, Erhard F., Finn
Thain, Frederic Barrat, Ganesh Goudar, Gautham R. Shenoy, Geoff Levand,
Greg Kurz, Gustavo A. R. Silva, Hari Bathini, Harish, Imre Kaloz, Joel
Stanley, Joe Perches, John Crispin, Jordan Niethe, Kajol Jain, Kamalesh
Babulal, Kees Cook, Laurent Dufour, Leonardo Bras, Li RongQing, Madhavan
Srinivasan, Mahesh Salgaonkar, Mark Cave-Ayland, Michal Suchanek, Milton
Miller, Mimi Zohar, Murilo Opsfelder Araujo, Nathan Chancellor, Nathan
Lynch, Naveen N. Rao, Nayna Jain, Nicholas Piggin, Oliver O'Halloran,
Palmer Dabbelt, Pedro Miraglia Franco de Carvalho, Philippe Bergheaud,
Pingfan Liu, Pratik Rajesh Sampat, Qian Cai, Qinglang Miao, Randy
Dunlap, Ravi Bangoria, Sachin Sant, Sam Bobroff, Sandipan Das, Santosh
Sivaraj, Satheesh Rajendran, Shirisha Ganta, Sourabh Jain, Srikar
Dronamraju, Stan Johnson, Stephen Rothwell, Thadeu Lima de Souza
Cascardo, Thiago Jung Bauermann, Tom Lane, Vaibhav Jain, Vladis Dronov,
Wei Yongjun, Wen Xiong, YueHaibing.
* tag 'powerpc-5.9-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (337 commits)
selftests/powerpc: Fix pkey syscall redefinitions
powerpc: Fix circular dependency between percpu.h and mmu.h
powerpc/powernv/sriov: Fix use of uninitialised variable
selftests/powerpc: Skip vmx/vsx/tar/etc tests on older CPUs
powerpc/40x: Fix assembler warning about r0
powerpc/papr_scm: Add support for fetching nvdimm 'fuel-gauge' metric
powerpc/papr_scm: Fetch nvdimm performance stats from PHYP
cpuidle: pseries: Fixup exit latency for CEDE(0)
cpuidle: pseries: Add function to parse extended CEDE records
cpuidle: pseries: Set the latency-hint before entering CEDE
selftests/powerpc: Fix online CPU selection
powerpc/perf: Consolidate perf_callchain_user_[64|32]()
powerpc/pseries/hotplug-cpu: Remove double free in error path
powerpc/pseries/mobility: Add pr_debug() for device tree changes
powerpc/pseries/mobility: Set pr_fmt()
powerpc/cacheinfo: Warn if cache object chain becomes unordered
powerpc/cacheinfo: Improve diagnostics about malformed cache lists
powerpc/cacheinfo: Use name@unit instead of full DT path in debug messages
powerpc/cacheinfo: Set pr_fmt()
powerpc: fix function annotations to avoid section mismatch warnings with gcc-10
...
Pull ptrace regset updates from Al Viro:
"Internal regset API changes:
- regularize copy_regset_{to,from}_user() callers
- switch to saner calling conventions for ->get()
- kill user_regset_copyout()
The ->put() side of things will have to wait for the next cycle,
unfortunately.
The balance is about -1KLoC and replacements for ->get() instances are
a lot saner"
* 'work.regset' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (41 commits)
regset: kill user_regset_copyout{,_zero}()
regset(): kill ->get_size()
regset: kill ->get()
csky: switch to ->regset_get()
xtensa: switch to ->regset_get()
parisc: switch to ->regset_get()
nds32: switch to ->regset_get()
nios2: switch to ->regset_get()
hexagon: switch to ->regset_get()
h8300: switch to ->regset_get()
openrisc: switch to ->regset_get()
riscv: switch to ->regset_get()
c6x: switch to ->regset_get()
ia64: switch to ->regset_get()
arc: switch to ->regset_get()
arm: switch to ->regset_get()
sh: convert to ->regset_get()
arm64: switch to ->regset_get()
mips: switch to ->regset_get()
sparc: switch to ->regset_get()
...
-----BEGIN PGP SIGNATURE-----
iQEzBAABCAAdFiEEq1nRK9aeMoq1VSgcnJ2qBz9kQNkFAl8qeCkACgkQnJ2qBz9k
QNlAGQf/YVruyVLZ7kCv6EMCHauXm3K1lEGpbXsTW04HpStxGx7mtLGN/Au+EYJR
VnRkCMt6TSMQGMBkNF83dUCwXHkeL1rd6frJBLVOErkg50nUuD4kjTVw9Lzw9itx
CPhKnPPlsRkDkZPxkg3WEdqPgzJREWBZUaB38QUPjYN46q7HfPYDANTh5wI1GiGs
27+PvzlttjhkQpQ14pYU/nu4xf/nmgmmHhgfsJArQP2EzYOrKxsWKhXS5uPdtNlf
mXiZMaqW2AlyDGlw3myOEySrrSuaR77M2bzDo7mjqffI9wSVTytKEhtg0i8OMWmv
pZ38OQobznnFoqzc1GL70IE0DEU48g==
=d81d
-----END PGP SIGNATURE-----
Merge tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs
Pull fsnotify updates from Jan Kara:
- fanotify fix for softlockups when there are many queued events
- performance improvement to reduce fsnotify overhead when not used
- Amir's implementation of fanotify events with names. With these you
can now efficiently monitor whole filesystem, eg to mirror changes to
another machine.
* tag 'fsnotify_for_v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-fs: (37 commits)
fanotify: compare fsid when merging name event
fsnotify: create method handle_inode_event() in fsnotify_operations
fanotify: report parent fid + child fid
fanotify: report parent fid + name + child fid
fanotify: add support for FAN_REPORT_NAME
fanotify: report events with parent dir fid to sb/mount/non-dir marks
fanotify: add basic support for FAN_REPORT_DIR_FID
fsnotify: remove check that source dentry is positive
fsnotify: send event with parent/name info to sb/mount/non-dir marks
audit: do not set FS_EVENT_ON_CHILD in audit marks mask
inotify: do not set FS_EVENT_ON_CHILD in non-dir mark mask
fsnotify: pass dir and inode arguments to fsnotify()
fsnotify: create helper fsnotify_inode()
fsnotify: send event to parent and child with single callback
inotify: report both events on parent and child with single callback
dnotify: report both events on parent and child with single callback
fanotify: no external fh buffer in fanotify_name_event
fanotify: use struct fanotify_info to parcel the variable size buffer
fsnotify: add object type "child" to object type iterator
fanotify: use FAN_EVENT_ON_CHILD as implicit flag on sb/mount/non-dir marks
...
I get the following error during compilation on my side:
kernel/trace/bpf_trace.c: In function 'bpf_do_trace_printk':
kernel/trace/bpf_trace.c:386:34: error: function 'bpf_do_trace_printk' can never be inlined because it uses variable argument lists
static inline __printf(1, 0) int bpf_do_trace_printk(const char *fmt, ...)
^
Fixes: ac5a72ea5c ("bpf: Use dedicated bpf_trace_printk event instead of trace_printk()")
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200806182612.1390883-1-sdf@google.com
Commit a5cbe05a66 ("bpf: Implement bpf iterator for
map elements") added bpf iterator support for
map elements. The map element bpf iterator requires
info to identify a particular map. In the above
commit, the attr->link_create.target_fd is used
to carry map_fd and an enum bpf_iter_link_info
is added to uapi to specify the target_fd actually
representing a map_fd:
enum bpf_iter_link_info {
BPF_ITER_LINK_UNSPEC = 0,
BPF_ITER_LINK_MAP_FD = 1,
MAX_BPF_ITER_LINK_INFO,
};
This is an extensible approach as we can grow
enumerator for pid, cgroup_id, etc. and we can
unionize target_fd for pid, cgroup_id, etc.
But in the future, there are chances that
more complex customization may happen, e.g.,
for tasks, it could be filtered based on
both cgroup_id and user_id.
This patch changed the uapi to have fields
__aligned_u64 iter_info;
__u32 iter_info_len;
for additional iter_info for link_create.
The iter_info is defined as
union bpf_iter_link_info {
struct {
__u32 map_fd;
} map;
};
So future extension for additional customization
will be easier. The bpf_iter_link_info will be
passed to target callback to validate and generic
bpf_iter framework does not need to deal it any
more.
Note that map_fd = 0 will be considered invalid
and -EBADF will be returned to user space.
Fixes: a5cbe05a66 ("bpf: Implement bpf iterator for map elements")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200805055056.1457463-1-yhs@fb.com
The crash_exclude_mem_range() function can only handle one memory region a time.
It will fail in the case in which the passed in area covers several memory
regions. In this case, it will only exclude the first region, then return,
but leave the later regions unsolved.
E.g in a NEC system with two usable RAM regions inside the low 1M:
...
BIOS-e820: [mem 0x0000000000000000-0x000000000003efff] usable
BIOS-e820: [mem 0x000000000003f000-0x000000000003ffff] reserved
BIOS-e820: [mem 0x0000000000040000-0x000000000009ffff] usable
It will only exclude the memory region [0, 0x3efff], the memory region
[0x40000, 0x9ffff] will still be added into /proc/vmcore, which may cause
the following failure when dumping vmcore:
ioremap on RAM at 0x0000000000040000 - 0x0000000000040fff
WARNING: CPU: 0 PID: 665 at arch/x86/mm/ioremap.c:186 __ioremap_caller+0x2c7/0x2e0
...
RIP: 0010:__ioremap_caller+0x2c7/0x2e0
...
cp: error reading '/proc/vmcore': Cannot allocate memory
kdump: saving vmcore failed
In order to fix this bug, let's extend the crash_exclude_mem_range()
to handle the overlapping ranges.
[ mingo: Amended the changelog. ]
Signed-off-by: Lianbo Jiang <lijiang@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Dave Young <dyoung@redhat.com>
Link: https://lore.kernel.org/r/20200804044933.1973-3-lijiang@redhat.com
x86:
* Report last CPU for debugging
* Emulate smaller MAXPHYADDR in the guest than in the host
* .noinstr and tracing fixes from Thomas
* nested SVM page table switching optimization and fixes
Generic:
* Unify shadow MMU cache data structures across architectures
-----BEGIN PGP SIGNATURE-----
iQFIBAABCAAyFiEE8TM4V0tmI4mGbHaCv/vSX3jHroMFAl8pC+oUHHBib256aW5p
QHJlZGhhdC5jb20ACgkQv/vSX3jHroNcOwgAjomqtEqQNlp7DdZT7VyyklzbxX1/
ud7v+oOJ8K4sFlf64lSthjPo3N9rzZCcw+yOXmuyuITngXOGc3tzIwXpCzpLtuQ1
WO1Ql3B/2dCi3lP5OMmsO1UAZqy9pKLg1dfeYUPk48P5+p7d/NPmk+Em5kIYzKm5
JsaHfCp2EEXomwmljNJ8PQ1vTjIQSSzlgYUBZxmCkaaX7zbEUMtxAQCStHmt8B84
33LczwXBm3viSWrzsoBV37I70+tseugiSGsCfUyupXOvq55d6D9FCqtCb45Hn4Vh
Ik8ggKdalsk/reiGEwNw1/3nr6mRMkHSbl+Mhc4waOIFf9dn0urgQgOaDg==
=YVx0
-----END PGP SIGNATURE-----
Merge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Pull KVM updates from Paolo Bonzini:
"s390:
- implement diag318
x86:
- Report last CPU for debugging
- Emulate smaller MAXPHYADDR in the guest than in the host
- .noinstr and tracing fixes from Thomas
- nested SVM page table switching optimization and fixes
Generic:
- Unify shadow MMU cache data structures across architectures"
* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm: (127 commits)
KVM: SVM: Fix sev_pin_memory() error handling
KVM: LAPIC: Set the TDCR settable bits
KVM: x86: Specify max TDP level via kvm_configure_mmu()
KVM: x86/mmu: Rename max_page_level to max_huge_page_level
KVM: x86: Dynamically calculate TDP level from max level and MAXPHYADDR
KVM: VXM: Remove temporary WARN on expected vs. actual EPTP level mismatch
KVM: x86: Pull the PGD's level from the MMU instead of recalculating it
KVM: VMX: Make vmx_load_mmu_pgd() static
KVM: x86/mmu: Add separate helper for shadow NPT root page role calc
KVM: VMX: Drop a duplicate declaration of construct_eptp()
KVM: nSVM: Correctly set the shadow NPT root level in its MMU role
KVM: Using macros instead of magic values
MIPS: KVM: Fix build error caused by 'kvm_run' cleanup
KVM: nSVM: remove nonsensical EXITINFO1 adjustment on nested NPF
KVM: x86: Add a capability for GUEST_MAXPHYADDR < HOST_MAXPHYADDR support
KVM: VMX: optimize #PF injection when MAXPHYADDR does not match
KVM: VMX: Add guest physical address check in EPT violation and misconfig
KVM: VMX: introduce vmx_need_pf_intercept
KVM: x86: update exception bitmap on CPUID changes
KVM: x86: rename update_bp_intercept to update_exception_bitmap
...
static priority level knowledge from non-scheduler code.
The three APIs for non-scheduler code to set SCHED_FIFO are:
- sched_set_fifo()
- sched_set_fifo_low()
- sched_set_normal()
These are two FIFO priority levels: default (high), and a 'low' priority level,
plus sched_set_normal() to set the policy back to non-SCHED_FIFO.
Since the changes affect a lot of non-scheduler code, we kept this in a separate
tree.
When merging to the latest upstream tree there's a conflict in drivers/spi/spi.c,
which can be resolved via:
sched_set_fifo(ctlr->kworker_task);
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=/7JH
-----END PGP SIGNATURE-----
Merge tag 'sched-fifo-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull sched/fifo updates from Ingo Molnar:
"This adds the sched_set_fifo*() encapsulation APIs to remove static
priority level knowledge from non-scheduler code.
The three APIs for non-scheduler code to set SCHED_FIFO are:
- sched_set_fifo()
- sched_set_fifo_low()
- sched_set_normal()
These are two FIFO priority levels: default (high), and a 'low'
priority level, plus sched_set_normal() to set the policy back to
non-SCHED_FIFO.
Since the changes affect a lot of non-scheduler code, we kept this in
a separate tree"
* tag 'sched-fifo-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (24 commits)
sched,tracing: Convert to sched_set_fifo()
sched: Remove sched_set_*() return value
sched: Remove sched_setscheduler*() EXPORTs
sched,psi: Convert to sched_set_fifo_low()
sched,rcutorture: Convert to sched_set_fifo_low()
sched,rcuperf: Convert to sched_set_fifo_low()
sched,locktorture: Convert to sched_set_fifo()
sched,irq: Convert to sched_set_fifo()
sched,watchdog: Convert to sched_set_fifo()
sched,serial: Convert to sched_set_fifo()
sched,powerclamp: Convert to sched_set_fifo()
sched,ion: Convert to sched_set_normal()
sched,powercap: Convert to sched_set_fifo*()
sched,spi: Convert to sched_set_fifo*()
sched,mmc: Convert to sched_set_fifo*()
sched,ivtv: Convert to sched_set_fifo*()
sched,drm/scheduler: Convert to sched_set_fifo*()
sched,msm: Convert to sched_set_fifo*()
sched,psci: Convert to sched_set_fifo*()
sched,drbd: Convert to sched_set_fifo*()
...
-----BEGIN PGP SIGNATURE-----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=M/tq
-----END PGP SIGNATURE-----
Merge tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity
Pull integrity updates from Mimi Zohar:
"The nicest change is the IMA policy rule checking. The other changes
include allowing the kexec boot cmdline line measure policy rules to
be defined in terms of the inode associated with the kexec kernel
image, making the IMA_APPRAISE_BOOTPARAM, which governs the IMA
appraise mode (log, fix, enforce), a runtime decision based on the
secure boot mode of the system, and including errno in the audit log"
* tag 'integrity-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/zohar/linux-integrity:
integrity: remove redundant initialization of variable ret
ima: move APPRAISE_BOOTPARAM dependency on ARCH_POLICY to runtime
ima: AppArmor satisfies the audit rule requirements
ima: Rename internal filter rule functions
ima: Support additional conditionals in the KEXEC_CMDLINE hook function
ima: Use the common function to detect LSM conditionals in a rule
ima: Move comprehensive rule validation checks out of the token parser
ima: Use correct type for the args_p member of ima_rule_entry.lsm elements
ima: Shallow copy the args_p member of ima_rule_entry.lsm elements
ima: Fail rule parsing when appraise_flag=blacklist is unsupportable
ima: Fail rule parsing when the KEY_CHECK hook is combined with an invalid cond
ima: Fail rule parsing when the KEXEC_CMDLINE hook is combined with an invalid cond
ima: Fail rule parsing when buffer hook functions have an invalid action
ima: Free the entire rule if it fails to parse
ima: Free the entire rule when deleting a list of rules
ima: Have the LSM free its audit rule
IMA: Add audit log for failure conditions
integrity: Add errno field in audit message
Running posix CPU timers in hard interrupt context has a few downsides:
- For PREEMPT_RT it cannot work as the expiry code needs to take
sighand lock, which is a 'sleeping spinlock' in RT. The original RT
approach of offloading the posix CPU timer handling into a high
priority thread was clumsy and provided no real benefit in general.
- For fine grained accounting it's just wrong to run this in context of
the timer interrupt because that way a process specific CPU time is
accounted to the timer interrupt.
- Long running timer interrupts caused by a large amount of expiring
timers which can be created and armed by unpriviledged user space.
There is no hard requirement to expire them in interrupt context.
If the signal is targeted at the task itself then it won't be delivered
before the task returns to user space anyway. If the signal is targeted at
a supervisor process then it might be slightly delayed, but posix CPU
timers are inaccurate anyway due to the fact that they are tied to the
tick.
Provide infrastructure to schedule task work which allows splitting the
posix CPU timer code into a quick check in interrupt context and a thread
context expiry and signal delivery function. This has to be enabled by
architectures as it requires that the architecture specific KVM
implementation handles pending task work before exiting to guest mode.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200730102337.783470146@linutronix.de
Split it up as a preparatory step to move the heavy lifting out of
interrupt context.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200730102337.677439437@linutronix.de
Architectures can have the requirement to add additional architecture
specific data to the VDSO data page which needs to be updated independent
of the timekeeper updates.
To protect these updates vs. concurrent readers and a conflicting update
through timekeeping, provide helper functions to make such updates safe.
vdso_update_begin() takes the timekeeper_lock to protect against a
potential update from timekeeper code and increments the VDSO sequence
count to signal data inconsistency to concurrent readers. vdso_update_end()
makes the sequence count even again to signal data consistency and drops
the timekeeper lock.
[ Sven: Add interrupt disable handling to the functions ]
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200804150124.41692-3-svens@linux.ibm.com
The count field is meant to tell if an update to nr_running
is an add or a subtract. Make it do so by adding the missing
minus sign.
Fixes: 9d246053a6 ("sched: Add a tracepoint to track rq->nr_running")
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200805203138.1411-1-pauld@redhat.com
Pull networking updates from David Miller:
1) Support 6Ghz band in ath11k driver, from Rajkumar Manoharan.
2) Support UDP segmentation in code TSO code, from Eric Dumazet.
3) Allow flashing different flash images in cxgb4 driver, from Vishal
Kulkarni.
4) Add drop frames counter and flow status to tc flower offloading,
from Po Liu.
5) Support n-tuple filters in cxgb4, from Vishal Kulkarni.
6) Various new indirect call avoidance, from Eric Dumazet and Brian
Vazquez.
7) Fix BPF verifier failures on 32-bit pointer arithmetic, from
Yonghong Song.
8) Support querying and setting hardware address of a port function via
devlink, use this in mlx5, from Parav Pandit.
9) Support hw ipsec offload on bonding slaves, from Jarod Wilson.
10) Switch qca8k driver over to phylink, from Jonathan McDowell.
11) In bpftool, show list of processes holding BPF FD references to
maps, programs, links, and btf objects. From Andrii Nakryiko.
12) Several conversions over to generic power management, from Vaibhav
Gupta.
13) Add support for SO_KEEPALIVE et al. to bpf_setsockopt(), from Dmitry
Yakunin.
14) Various https url conversions, from Alexander A. Klimov.
15) Timestamping and PHC support for mscc PHY driver, from Antoine
Tenart.
16) Support bpf iterating over tcp and udp sockets, from Yonghong Song.
17) Support 5GBASE-T i40e NICs, from Aleksandr Loktionov.
18) Add kTLS RX HW offload support to mlx5e, from Tariq Toukan.
19) Fix the ->ndo_start_xmit() return type to be netdev_tx_t in several
drivers. From Luc Van Oostenryck.
20) XDP support for xen-netfront, from Denis Kirjanov.
21) Support receive buffer autotuning in MPTCP, from Florian Westphal.
22) Support EF100 chip in sfc driver, from Edward Cree.
23) Add XDP support to mvpp2 driver, from Matteo Croce.
24) Support MPTCP in sock_diag, from Paolo Abeni.
25) Commonize UDP tunnel offloading code by creating udp_tunnel_nic
infrastructure, from Jakub Kicinski.
26) Several pci_ --> dma_ API conversions, from Christophe JAILLET.
27) Add FLOW_ACTION_POLICE support to mlxsw, from Ido Schimmel.
28) Add SK_LOOKUP bpf program type, from Jakub Sitnicki.
29) Refactor a lot of networking socket option handling code in order to
avoid set_fs() calls, from Christoph Hellwig.
30) Add rfc4884 support to icmp code, from Willem de Bruijn.
31) Support TBF offload in dpaa2-eth driver, from Ioana Ciornei.
32) Support XDP_REDIRECT in qede driver, from Alexander Lobakin.
33) Support PCI relaxed ordering in mlx5 driver, from Aya Levin.
34) Support TCP syncookies in MPTCP, from Flowian Westphal.
35) Fix several tricky cases of PMTU handling wrt. briding, from Stefano
Brivio.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (2056 commits)
net: thunderx: initialize VF's mailbox mutex before first usage
usb: hso: remove bogus check for EINPROGRESS
usb: hso: no complaint about kmalloc failure
hso: fix bailout in error case of probe
ip_tunnel_core: Fix build for archs without _HAVE_ARCH_IPV6_CSUM
selftests/net: relax cpu affinity requirement in msg_zerocopy test
mptcp: be careful on subflow creation
selftests: rtnetlink: make kci_test_encap() return sub-test result
selftests: rtnetlink: correct the final return value for the test
net: dsa: sja1105: use detected device id instead of DT one on mismatch
tipc: set ub->ifindex for local ipv6 address
ipv6: add ipv6_dev_find()
net: openvswitch: silence suspicious RCU usage warning
Revert "vxlan: fix tos value before xmit"
ptp: only allow phase values lower than 1 period
farsync: switch from 'pci_' to 'dma_' API
wan: wanxl: switch from 'pci_' to 'dma_' API
hv_netvsc: do not use VF device if link is down
dpaa2-eth: Fix passing zero to 'PTR_ERR' warning
net: macb: Properly handle phylink on at91sam9x
...
Here is the "big" set of changes to the driver core, and some drivers
using the changes, for 5.9-rc1.
"Biggest" thing in here is the device link exposure in sysfs, to help
to tame the madness that is SoC device tree representations and driver
interactions with it.
Other stuff in here that is interesting is:
- device probe log helper so that drivers can report problems in
a unified way easier.
- devres functions added
- DEVICE_ATTR_ADMIN_* macro added to make it harder to write
incorrect sysfs file permissions
- documentation cleanups
- ability for debugfs to be present in the kernel, yet not
exposed to userspace. Needed for systems that want it
enabled, but do not trust users, so they can still use some
kernel functions that were otherwise disabled.
- other minor fixes and cleanups
The patches outside of drivers/base/ all have acks from the respective
subsystem maintainers to go through this tree instead of theirs.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXylhOQ8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ylGdACeKqxm8IIDZycj0QjLUlPiEwVIROgAnjpf5jAB
mb4jMvgEGsB6/FwxypPG
=RUss
-----END PGP SIGNATURE-----
Merge tag 'driver-core-5.9-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 changes to the driver core, and some drivers
using the changes, for 5.9-rc1.
"Biggest" thing in here is the device link exposure in sysfs, to help
to tame the madness that is SoC device tree representations and driver
interactions with it.
Other stuff in here that is interesting is:
- device probe log helper so that drivers can report problems in a
unified way easier.
- devres functions added
- DEVICE_ATTR_ADMIN_* macro added to make it harder to write
incorrect sysfs file permissions
- documentation cleanups
- ability for debugfs to be present in the kernel, yet not exposed to
userspace. Needed for systems that want it enabled, but do not
trust users, so they can still use some kernel functions that were
otherwise disabled.
- other minor fixes and cleanups
The patches outside of drivers/base/ all have acks from the respective
subsystem maintainers to go through this tree instead of theirs.
All of these have been in linux-next with no reported issues"
* tag 'driver-core-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (39 commits)
drm/bridge: lvds-codec: simplify error handling
drm/bridge/sii8620: fix resource acquisition error handling
driver core: add deferring probe reason to devices_deferred property
driver core: add device probe log helper
driver core: Avoid binding drivers to dead devices
Revert "test_firmware: Test platform fw loading on non-EFI systems"
firmware_loader: EFI firmware loader must handle pre-allocated buffer
selftest/firmware: Add selftest timeout in settings
test_firmware: Test platform fw loading on non-EFI systems
driver core: Change delimiter in devlink device's name to "--"
debugfs: Add access restriction option
tracefs: Remove unnecessary debug_fs checks.
driver core: Fix probe_count imbalance in really_probe()
kobject: remove unused KOBJ_MAX action
driver core: Fix sleeping in invalid context during device link deletion
driver core: Add waiting_for_supplier sysfs file for devices
driver core: Add state_synced sysfs file for devices that support it
driver core: Expose device link details in sysfs
driver core: Drop mention of obsolete bus rwsem from kernel-doc
debugfs: file: Remove unnecessary cast in kfree()
...
Here is the large set of char and misc and other driver subsystem
patches for 5.9-rc1. Lots of new driver submissions in here, and
cleanups and features for existing drivers.
Highlights are:
- habanalabs driver updates
- coresight driver updates
- nvmem driver updates
- huge number of "W=1" build warning cleanups from Lee Jones
- dyndbg updates
- virtbox driver fixes and updates
- soundwire driver updates
- mei driver updates
- phy driver updates
- fpga driver updates
- lots of smaller individual misc/char driver cleanups and fixes
Full details are in the shortlog.
All of these have been in linux-next with no reported issues.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-----BEGIN PGP SIGNATURE-----
iG0EABECAC0WIQT0tgzFv3jCIUoxPcsxR9QN2y37KQUCXylccQ8cZ3JlZ0Brcm9h
aC5jb20ACgkQMUfUDdst+ymofgCfZ1CxNWd0ZVM0YIn8cY9gO6ON7MsAnRq48hvn
Vjf4rKM73GC11bVF4Gyy
=Xq1R
-----END PGP SIGNATURE-----
Merge tag 'char-misc-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the large set of char and misc and other driver subsystem
patches for 5.9-rc1. Lots of new driver submissions in here, and
cleanups and features for existing drivers.
Highlights are:
- habanalabs driver updates
- coresight driver updates
- nvmem driver updates
- huge number of "W=1" build warning cleanups from Lee Jones
- dyndbg updates
- virtbox driver fixes and updates
- soundwire driver updates
- mei driver updates
- phy driver updates
- fpga driver updates
- lots of smaller individual misc/char driver cleanups and fixes
Full details are in the shortlog.
All of these have been in linux-next with no reported issues"
* tag 'char-misc-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (322 commits)
habanalabs: remove unused but set variable 'ctx_asid'
nvmem: qcom-spmi-sdam: Enable multiple devices
dt-bindings: nvmem: SID: add binding for A100's SID controller
nvmem: update Kconfig description
nvmem: qfprom: Add fuse blowing support
dt-bindings: nvmem: Add properties needed for blowing fuses
dt-bindings: nvmem: qfprom: Convert to yaml
nvmem: qfprom: use NVMEM_DEVID_AUTO for multiple instances
nvmem: core: add support to auto devid
nvmem: core: Add nvmem_cell_read_u8()
nvmem: core: Grammar fixes for help text
nvmem: sc27xx: add sc2730 efuse support
nvmem: Enforce nvmem stride in the sysfs interface
MAINTAINERS: Add git tree for NVMEM FRAMEWORK
nvmem: sprd: Fix return value of sprd_efuse_probe()
drivers: android: Fix the SPDX comment style
drivers: android: Fix a variable declaration coding style issue
drivers: android: Remove braces for a single statement if-else block
drivers: android: Remove the use of else after return
drivers: android: Fix a variable declaration coding style issue
...
If a TAINT_PROPRIETARY_MODULE exports symbol, inherit the taint flag
for all modules importing these symbols, and don't allow loading
symbols from TAINT_PROPRIETARY_MODULE modules if the module previously
imported gplonly symbols. Add a anti-circumvention devices so people
don't accidentally get themselves into trouble this way.
Comment from Greg:
"Ah, the proven-to-be-illegal "GPL Condom" defense :)"
[jeyu: pr_info -> pr_err and pr_warn as per discussion]
Link: http://lore.kernel.org/r/20200730162957.GA22469@lst.de
Acked-by: Daniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jessica Yu <jeyu@kernel.org>
while to come. Changes include:
- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS URLs
- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again for a
while. Unless we decide to switch to asciidoc or something...:)
- Lots of typo fixes, warning fixes, and more.
-----BEGIN PGP SIGNATURE-----
iQFDBAABCAAtFiEEIw+MvkEiF49krdp9F0NaE2wMflgFAl8oVkwPHGNvcmJldEBs
d24ubmV0AAoJEBdDWhNsDH5YoW8H/jJ/xnXFn7tkgVPQAlL3k5HCnK7A5nDP9RVR
cg1pTx1cEFdjzxPlJyExU6/v+AImOvtweHXC+JDK7YcJ6XFUNYXJI3LxL5KwUXbY
BL/xRFszDSXH2C7SJF5GECcFYp01e/FWSLN3yWAh+g+XwsKiTJ8q9+CoIDkHfPGO
7oQsHKFu6s36Af0LfSgxk4sVB7EJbo8e4psuPsP5SUrl+oXRO43Put0rXkR4yJoH
9oOaB51Do5fZp8I4JVAqGXvpXoExyLMO4yw0mASm6YSZ3KyjR8Fae+HD9Cq4ZuwY
0uzb9K+9NEhqbfwtyBsi99S64/6Zo/MonwKwevZuhtsDTK4l4iU=
=JQLZ
-----END PGP SIGNATURE-----
Merge tag 'docs-5.9' of git://git.lwn.net/linux
Pull documentation updates from Jonathan Corbet:
"It's been a busy cycle for documentation - hopefully the busiest for a
while to come. Changes include:
- Some new Chinese translations
- Progress on the battle against double words words and non-HTTPS
URLs
- Some block-mq documentation
- More RST conversions from Mauro. At this point, that task is
essentially complete, so we shouldn't see this kind of churn again
for a while. Unless we decide to switch to asciidoc or
something...:)
- Lots of typo fixes, warning fixes, and more"
* tag 'docs-5.9' of git://git.lwn.net/linux: (195 commits)
scripts/kernel-doc: optionally treat warnings as errors
docs: ia64: correct typo
mailmap: add entry for <alobakin@marvell.com>
doc/zh_CN: add cpu-load Chinese version
Documentation/admin-guide: tainted-kernels: fix spelling mistake
MAINTAINERS: adjust kprobes.rst entry to new location
devices.txt: document rfkill allocation
PCI: correct flag name
docs: filesystems: vfs: correct flag name
docs: filesystems: vfs: correct sync_mode flag names
docs: path-lookup: markup fixes for emphasis
docs: path-lookup: more markup fixes
docs: path-lookup: fix HTML entity mojibake
CREDITS: Replace HTTP links with HTTPS ones
docs: process: Add an example for creating a fixes tag
doc/zh_CN: add Chinese translation prefer section
doc/zh_CN: add clearing-warn-once Chinese version
doc/zh_CN: add admin-guide index
doc:it_IT: process: coding-style.rst: Correct __maybe_unused compiler label
futex: MAINTAINERS: Re-add selftests directory
...
-----BEGIN PGP SIGNATURE-----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=ZcMq
-----END PGP SIGNATURE-----
Merge tag 'printk-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux
Pull printk updates from Petr Mladek:
- Herbert Xu made printk header file self-contained.
- Andy Shevchenko and Sergey Senozhatsky cleaned up console->setup()
error handling.
- Andy Shevchenko did some cleanups (e.g. sparse warning) in vsprintf
code.
- Minor documentation updates.
* tag 'printk-for-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
lib/vsprintf: Force type of flags value for gfp_t
lib/vsprintf: Replace custom spec to print decimals with generic one
lib/vsprintf: Replace hidden BUILD_BUG_ON() with static_assert()
printk: Make linux/printk.h self-contained
doc:kmsg: explicitly state the return value in case of SEEK_CUR
Replace HTTP links with HTTPS ones: vsprintf
hvc: unify console setup naming
console: Fix trivia typo 'change' -> 'chance'
console: Propagate error code from console ->setup()
tty: hvc: Return proper error code from console ->setup() hook
serial: sunzilog: Return proper error code from console ->setup() hook
serial: sunsab: Return proper error code from console ->setup() hook
mips: Return proper error code from console ->setup() hook
entry/exit functionality based on the recent X86 effort to ensure
correctness of entry/exit vs. RCU and instrumentation.
As this functionality and the required entry/exit sequences are not
architecture specific, sharing them allows other architectures to benefit
instead of copying the same code over and over again.
This branch was kept standalone to allow others to work on it. The
conversion of x86 comes in a seperate pull request which obviously is based
on this branch.
-----BEGIN PGP SIGNATURE-----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=y2Ew
-----END PGP SIGNATURE-----
Merge tag 'core-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull generic kernel entry/exit code from Thomas Gleixner:
"Generic implementation of common syscall, interrupt and exception
entry/exit functionality based on the recent X86 effort to ensure
correctness of entry/exit vs RCU and instrumentation.
As this functionality and the required entry/exit sequences are not
architecture specific, sharing them allows other architectures to
benefit instead of copying the same code over and over again.
This branch was kept standalone to allow others to work on it. The
conversion of x86 comes in a seperate pull request which obviously is
based on this branch"
* tag 'core-entry-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
entry: Correct __secure_computing() stub
entry: Correct 'noinstr' attributes
entry: Provide infrastructure for work before transitioning to guest mode
entry: Provide generic interrupt entry/exit code
entry: Provide generic syscall exit function
entry: Provide generic syscall entry functionality
seccomp: Provide stub for __secure_computing()
- Prevent unnecessary timer softirq invocations by extending the tracking
of the next expiring timer in the timer wheel beyond the existing NOHZ
functionality. The tracking overhead at enqueue time is within the
noise, but on sensitive workloads the avoidance of the soft interrupt
invocation is a measurable improvement.
- The obligatory new clocksource driver for Ingenic X100 OST
- The usual fixes, improvements, cleanups and extensions for newer chip
variants all over the driver space.
-----BEGIN PGP SIGNATURE-----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=uJnp
-----END PGP SIGNATURE-----
Merge tag 'timers-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer updates from Thomas Gleixner:
"Time, timers and related driver updates:
- Prevent unnecessary timer softirq invocations by extending the
tracking of the next expiring timer in the timer wheel beyond the
existing NOHZ functionality.
The tracking overhead at enqueue time is within the noise, but on
sensitive workloads the avoidance of the soft interrupt invocation
is a measurable improvement.
- The obligatory new clocksource driver for Ingenic X100 OST
- The usual fixes, improvements, cleanups and extensions for newer
chip variants all over the driver space"
* tag 'timers-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (28 commits)
timers: Recalculate next timer interrupt only when necessary
clocksource/drivers/ingenic: Add support for the Ingenic X1000 OST.
dt-bindings: timer: Add Ingenic X1000 OST bindings.
clocksource/drivers: Replace HTTP links with HTTPS ones
clocksource/drivers/nomadik-mtu: Handle 32kHz clock
clocksource/drivers/sh_cmt: Use "kHz" for kilohertz
clocksource/drivers/imx: Add support for i.MX TPM driver with ARM64
clocksource/drivers/ingenic: Add high resolution timer support for SMP/SMT.
timers: Lower base clock forwarding threshold
timers: Remove must_forward_clk
timers: Spare timer softirq until next expiry
timers: Expand clk forward logic beyond nohz
timers: Reuse next expiry cache after nohz exit
timers: Always keep track of next expiry
timers: Optimize _next_timer_interrupt() level iteration
timers: Add comments about calc_index() ceiling work
timers: Move trigger_dyntick_cpu() to enqueue_timer()
timers: Use only bucket expiry for base->next_expiry value
timers: Preserve higher bits of expiration on index calculation
clocksource/drivers/timer-atmel-tcb: Add sama5d2 support
...
- Infrastructure to allow building irqchip drivers as modules
- Consolidation of irqchip ACPI probing
- Removal of the EOI-preflow interrupt handler which was required for
SPARC support and became obsolete after SPARC was converted to
use sparse interrupts.
- Cleanups, fixes and improvements all over the place
-----BEGIN PGP SIGNATURE-----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=KA8b
-----END PGP SIGNATURE-----
Merge tag 'irq-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
"The usual boring updates from the interrupt subsystem:
- Infrastructure to allow building irqchip drivers as modules
- Consolidation of irqchip ACPI probing
- Removal of the EOI-preflow interrupt handler which was required for
SPARC support and became obsolete after SPARC was converted to use
sparse interrupts.
- Cleanups, fixes and improvements all over the place"
* tag 'irq-core-2020-08-04' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (51 commits)
irqchip/loongson-pch-pic: Fix the misused irq flow handler
irqchip/loongson-htvec: Support 8 groups of HT vectors
irqchip/loongson-liointc: Fix misuse of gc->mask_cache
dt-bindings: interrupt-controller: Update Loongson HTVEC description
irqchip/imx-intmux: Fix irqdata regs save in imx_intmux_runtime_suspend()
irqchip/imx-intmux: Implement intmux runtime power management
irqchip/gic-v4.1: Use GFP_ATOMIC flag in allocate_vpe_l1_table()
irqchip: Fix IRQCHIP_PLATFORM_DRIVER_* compilation by including module.h
irqchip/stm32-exti: Map direct event to irq parent
irqchip/mtk-cirq: Convert to a platform driver
irqchip/mtk-sysirq: Convert to a platform driver
irqchip/qcom-pdc: Switch to using IRQCHIP_PLATFORM_DRIVER helper macros
irqchip: Add IRQCHIP_PLATFORM_DRIVER_BEGIN/END and IRQCHIP_MATCH helper macros
irqchip: irq-bcm2836.h: drop a duplicated word
irqchip/gic-v4.1: Ensure accessing the correct RD when writing INVALLR
irqchip/irq-bcm7038-l1: Guard uses of cpu_logical_map
irqchip/gic-v3: Remove unused register definition
irqchip/qcom-pdc: Allow QCOM_PDC to be loadable as a permanent module
genirq: Export irq_chip_retrigger_hierarchy and irq_chip_set_vcpu_affinity_parent
irqdomain: Export irq_domain_update_bus_token
...
- make support for dma_ops optional
- move more code out of line
- add generic support for a dma_ops bypass mode
- misc cleanups
-----BEGIN PGP SIGNATURE-----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=90UK
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping updates from Christoph Hellwig:
- make support for dma_ops optional
- move more code out of line
- add generic support for a dma_ops bypass mode
- misc cleanups
* tag 'dma-mapping-5.9' of git://git.infradead.org/users/hch/dma-mapping:
dma-contiguous: cleanup dma_alloc_contiguous
dma-debug: use named initializers for dir2name
powerpc: use the generic dma_ops_bypass mode
dma-mapping: add a dma_ops_bypass flag to struct device
dma-mapping: make support for dma ops optional
dma-mapping: inline the fast path dma-direct calls
dma-mapping: move the remaining DMA API calls out of line
On exit, if a process is preempted after the trace_sched_process_exit()
tracepoint but before the process is done exiting, then when it gets
scheduled in, the function tracers will not filter it properly against the
function tracing pid filters.
That is because the function tracing pid filters hooks to the
sched_process_exit() tracepoint to remove the exiting task's pid from the
filter list. Because the filtering happens at the sched_switch tracepoint,
when the exiting task schedules back in to finish up the exit, it will no
longer be in the function pid filtering tables.
This was noticeable in the notrace self tests on a preemptable kernel, as
the tests would fail as it exits and preempted after being taken off the
notrace filter table and on scheduling back in it would not be in the
notrace list, and then the ending of the exit function would trace. The test
detected this and would fail.
Cc: stable@vger.kernel.org
Cc: Namhyung Kim <namhyung@kernel.org>
Fixes: 1e10486ffe ("ftrace: Add 'function-fork' trace option")
Fixes: c37775d578 ("tracing: Add infrastructure to allow set_event_pid to follow children"
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXygcpgAKCRCRxhvAZXjc
ogPeAQDv1ncqtNroFAC4pJ4tQhH7JSjW0OltiMk/AocY/J2SdQD9GJ15luYJ0/om
697q/Z68sndRynhdoZlMuf3oYuBlHQw=
=3ZhE
-----END PGP SIGNATURE-----
Merge tag 'close-range-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull close_range() implementation from Christian Brauner:
"This adds the close_range() syscall. It allows to efficiently close a
range of file descriptors up to all file descriptors of a calling
task.
This is coordinated with the FreeBSD folks which have copied our
version of this syscall and in the meantime have already merged it in
April 2019:
https://reviews.freebsd.org/D21627https://svnweb.freebsd.org/base?view=revision&revision=359836
The syscall originally came up in a discussion around the new mount
API and making new file descriptor types cloexec by default. During
this discussion, Al suggested the close_range() syscall.
First, it helps to close all file descriptors of an exec()ing task.
This can be done safely via (quoting Al's example from [1] verbatim):
/* that exec is sensitive */
unshare(CLONE_FILES);
/* we don't want anything past stderr here */
close_range(3, ~0U);
execve(....);
The code snippet above is one way of working around the problem that
file descriptors are not cloexec by default. This is aggravated by the
fact that we can't just switch them over without massively regressing
userspace. For a whole class of programs having an in-kernel method of
closing all file descriptors is very helpful (e.g. demons, service
managers, programming language standard libraries, container managers
etc.).
Second, it allows userspace to avoid implementing closing all file
descriptors by parsing through /proc/<pid>/fd/* and calling close() on
each file descriptor and other hacks. From looking at various
large(ish) userspace code bases this or similar patterns are very
common in service managers, container runtimes, and programming
language runtimes/standard libraries such as Python or Rust.
In addition, the syscall will also work for tasks that do not have
procfs mounted and on kernels that do not have procfs support compiled
in. In such situations the only way to make sure that all file
descriptors are closed is to call close() on each file descriptor up
to UINT_MAX or RLIMIT_NOFILE, OPEN_MAX trickery.
Based on Linus' suggestion close_range() also comes with a new flag
CLOSE_RANGE_UNSHARE to more elegantly handle file descriptor dropping
right before exec. This would usually be expressed in the sequence:
unshare(CLONE_FILES);
close_range(3, ~0U);
as pointed out by Linus it might be desirable to have this be a part
of close_range() itself under a new flag CLOSE_RANGE_UNSHARE which
gets especially handy when we're closing all file descriptors above a
certain threshold.
Test-suite as always included"
* tag 'close-range-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
tests: add CLOSE_RANGE_UNSHARE tests
close_range: add CLOSE_RANGE_UNSHARE
tests: add close_range() tests
arch: wire-up close_range()
open: add close_range()
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXygegQAKCRCRxhvAZXjc
olWZAQCMPbhI/20LA3OYJ6s+BgBEnm89PymvlHcym6Z4AvTungD+KqZonIYuxWgi
6Ttlv/fzgFFbXgJgbuass5mwFVoN5wM=
=oK7d
-----END PGP SIGNATURE-----
Merge tag 'cap-checkpoint-restore-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull checkpoint-restore updates from Christian Brauner:
"This enables unprivileged checkpoint/restore of processes.
Given that this work has been going on for quite some time the first
sentence in this summary is hopefully more exciting than the actual
final code changes required. Unprivileged checkpoint/restore has seen
a frequent increase in interest over the last two years and has thus
been one of the main topics for the combined containers &
checkpoint/restore microconference since at least 2018 (cf. [1]).
Here are just the three most frequent use-cases that were brought forward:
- The JVM developers are integrating checkpoint/restore into a Java
VM to significantly decrease the startup time.
- In high-performance computing environment a resource manager will
typically be distributing jobs where users are always running as
non-root. Long-running and "large" processes with significant
startup times are supposed to be checkpointed and restored with
CRIU.
- Container migration as a non-root user.
In all of these scenarios it is either desirable or required to run
without CAP_SYS_ADMIN. The userspace implementation of
checkpoint/restore CRIU already has the pull request for supporting
unprivileged checkpoint/restore up (cf. [2]).
To enable unprivileged checkpoint/restore a new dedicated capability
CAP_CHECKPOINT_RESTORE is introduced. This solution has last been
discussed in 2019 in a talk by Google at Linux Plumbers (cf. [1]
"Update on Task Migration at Google Using CRIU") with Adrian and
Nicolas providing the implementation now over the last months. In
essence, this allows the CRIU binary to be installed with the
CAP_CHECKPOINT_RESTORE vfs capability set thereby enabling
unprivileged users to restore processes.
To make this possible the following permissions are altered:
- Selecting a specific PID via clone3() set_tid relaxed from userns
CAP_SYS_ADMIN to CAP_CHECKPOINT_RESTORE.
- Selecting a specific PID via /proc/sys/kernel/ns_last_pid relaxed
from userns CAP_SYS_ADMIN to CAP_CHECKPOINT_RESTORE.
- Accessing /proc/pid/map_files relaxed from init userns
CAP_SYS_ADMIN to init userns CAP_CHECKPOINT_RESTORE.
- Changing /proc/self/exe from userns CAP_SYS_ADMIN to userns
CAP_CHECKPOINT_RESTORE.
Of these four changes the /proc/self/exe change deserves a few words
because the reasoning behind even restricting /proc/self/exe changes
in the first place is just full of historical quirks and tracking this
down was a questionable version of fun that I'd like to spare others.
In short, it is trivial to change /proc/self/exe as an unprivileged
user, i.e. without userns CAP_SYS_ADMIN right now. Either via ptrace()
or by simply intercepting the elf loader in userspace during exec.
Nicolas was nice enough to even provide a POC for the latter (cf. [3])
to illustrate this fact.
The original patchset which introduced PR_SET_MM_MAP had no
permissions around changing the exe link. They too argued that it is
trivial to spoof the exe link already which is true. The argument
brought up against this was that the Tomoyo LSM uses the exe link in
tomoyo_manager() to detect whether the calling process is a policy
manager. This caused changing the exe links to be guarded by userns
CAP_SYS_ADMIN.
All in all this rather seems like a "better guard it with something
rather than nothing" argument which imho doesn't qualify as a great
security policy. Again, because spoofing the exe link is possible for
the calling process so even if this were security relevant it was
broken back then and would be broken today. So technically, dropping
all permissions around changing the exe link would probably be
possible and would send a clearer message to any userspace that relies
on /proc/self/exe for security reasons that they should stop doing
this but for now we're only relaxing the exe link permissions from
userns CAP_SYS_ADMIN to userns CAP_CHECKPOINT_RESTORE.
There's a final uapi change in here. Changing the exe link used to
accidently return EINVAL when the caller lacked the necessary
permissions instead of the more correct EPERM. This pr contains a
commit fixing this. I assume that userspace won't notice or care and
if they do I will revert this commit. But since we are changing the
permissions anyway it seems like a good opportunity to try this fix.
With these changes merged unprivileged checkpoint/restore will be
possible and has already been tested by various users"
[1] LPC 2018
1. "Task Migration at Google Using CRIU"
https://www.youtube.com/watch?v=yI_1cuhoDgA&t=12095
2. "Securely Migrating Untrusted Workloads with CRIU"
https://www.youtube.com/watch?v=yI_1cuhoDgA&t=14400
LPC 2019
1. "CRIU and the PID dance"
https://www.youtube.com/watch?v=LN2CUgp8deo&list=PLVsQ_xZBEyN30ZA3Pc9MZMFzdjwyz26dO&index=9&t=2m48s
2. "Update on Task Migration at Google Using CRIU"
https://www.youtube.com/watch?v=LN2CUgp8deo&list=PLVsQ_xZBEyN30ZA3Pc9MZMFzdjwyz26dO&index=9&t=1h2m8s
[2] https://github.com/checkpoint-restore/criu/pull/1155
[3] https://github.com/nviennot/run_as_exe
* tag 'cap-checkpoint-restore-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
selftests: add clone3() CAP_CHECKPOINT_RESTORE test
prctl: exe link permission error changed from -EINVAL to -EPERM
prctl: Allow local CAP_CHECKPOINT_RESTORE to change /proc/self/exe
proc: allow access in init userns for map_files with CAP_CHECKPOINT_RESTORE
pid_namespace: use checkpoint_restore_ns_capable() for ns_last_pid
pid: use checkpoint_restore_ns_capable() for set_tid
capabilities: Introduce CAP_CHECKPOINT_RESTORE
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXyge/QAKCRCRxhvAZXjc
oildAQCCWpnTeXm6hrIE3VZ36X5npFtbaEthdBVAUJM7mo0FYwEA8+Wbnubg6jCw
mztkXCnTfU7tApUdhKtQzcpEws45/Qk=
=REE/
-----END PGP SIGNATURE-----
Merge tag 'fork-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull fork cleanups from Christian Brauner:
"This is cleanup series from when we reworked a chunk of the process
creation paths in the kernel and switched to struct
{kernel_}clone_args.
High-level this does two main things:
- Remove the double export of both do_fork() and _do_fork() where
do_fork() used the incosistent legacy clone calling convention.
Now we only export _do_fork() which is based on struct
kernel_clone_args.
- Remove the copy_thread_tls()/copy_thread() split making the
architecture specific HAVE_COYP_THREAD_TLS config option obsolete.
This switches all remaining architectures to select
HAVE_COPY_THREAD_TLS and thus to the copy_thread_tls() calling
convention. The current split makes the process creation codepaths
more convoluted than they need to be. Each architecture has their own
copy_thread() function unless it selects HAVE_COPY_THREAD_TLS then it
has a copy_thread_tls() function.
The split is not needed anymore nowadays, all architectures support
CLONE_SETTLS but quite a few of them never bothered to select
HAVE_COPY_THREAD_TLS and instead simply continued to use copy_thread()
and use the old calling convention. Removing this split cleans up the
process creation codepaths and paves the way for implementing clone3()
on such architectures since it requires the copy_thread_tls() calling
convention.
After having made each architectures support copy_thread_tls() this
series simply renames that function back to copy_thread(). It also
switches all architectures that call do_fork() directly over to
_do_fork() and the struct kernel_clone_args calling convention. This
is a corollary of switching the architectures that did not yet support
it over to copy_thread_tls() since do_fork() is conditional on not
supporting copy_thread_tls() (Mostly because it lacks a separate
argument for tls which is trivial to fix but there's no need for this
function to exist.).
The do_fork() removal is in itself already useful as it allows to to
remove the export of both do_fork() and _do_fork() we currently have
in favor of only _do_fork(). This has already been discussed back when
we added clone3(). The legacy clone() calling convention is - as is
probably well-known - somewhat odd:
#
# ABI hall of shame
#
config CLONE_BACKWARDS
config CLONE_BACKWARDS2
config CLONE_BACKWARDS3
that is aggravated by the fact that some architectures such as sparc
follow the CLONE_BACKWARDSx calling convention but don't really select
the corresponding config option since they call do_fork() directly.
So do_fork() enforces a somewhat arbitrary calling convention in the
first place that doesn't really help the individual architectures that
deviate from it. They can thus simply be switched to _do_fork()
enforcing a single calling convention. (I really hope that any new
architectures will __not__ try to implement their own calling
conventions...)
Most architectures already have made a similar switch (m68k comes to
mind).
Overall this removes more code than it adds even with a good portion
of added comments. It simplifies a chunk of arch specific assembly
either by moving the code into C or by simply rewriting the assembly.
Architectures that have been touched in non-trivial ways have all been
actually boot and stress tested: sparc and ia64 have been tested with
Debian 9 images. They are the two architectures which have been
touched the most. All non-trivial changes to architectures have seen
acks from the relevant maintainers. nios2 with a custom built
buildroot image. h8300 I couldn't get something bootable to test on
but the changes have been fairly automatic and I'm sure we'll hear
people yell if I broke something there.
All other architectures that have been touched in trivial ways have
been compile tested for each single patch of the series via git rebase
-x "make ..." v5.8-rc2. arm{64} and x86{_64} have been boot tested
even though they have just been trivially touched (removal of the
HAVE_COPY_THREAD_TLS macro from their Kconfig) because well they are
basically "core architectures" and since it is trivial to get your
hands on a useable image"
* tag 'fork-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
arch: rename copy_thread_tls() back to copy_thread()
arch: remove HAVE_COPY_THREAD_TLS
unicore: switch to copy_thread_tls()
sh: switch to copy_thread_tls()
nds32: switch to copy_thread_tls()
microblaze: switch to copy_thread_tls()
hexagon: switch to copy_thread_tls()
c6x: switch to copy_thread_tls()
alpha: switch to copy_thread_tls()
fork: remove do_fork()
h8300: select HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
nios2: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
ia64: enable HAVE_COPY_THREAD_TLS, switch to kernel_clone_args
sparc: unconditionally enable HAVE_COPY_THREAD_TLS
sparc: share process creation helpers between sparc and sparc64
sparc64: enable HAVE_COPY_THREAD_TLS
fork: fold legacy_clone_args_valid() into _do_fork()
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXygcLwAKCRCRxhvAZXjc
ohajAP4n5E3BmN0jpIviXT4eNhP62jzxJtxlVXtgGT3D8b1mpQEA5n8NSOlQLoAh
yUGsjtwR9xDcHMcrhXD3yN6eYJSK0A8=
=tn4R
-----END PGP SIGNATURE-----
Merge tag 'threads-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread updates from Christian Brauner:
"This contains the changes to add the missing support for attaching to
time namespaces via pidfds.
Last cycle setns() was changed to support attaching to multiple
namespaces atomically. This requires all namespaces to have a point of
no return where they can't fail anymore.
Specifically, <namespace-type>_install() is allowed to perform
permission checks and install the namespace into the new struct nsset
that it has been given but it is not allowed to make visible changes
to the affected task. Once <namespace-type>_install() returns,
anything that the given namespace type additionally requires to be
setup needs to ideally be done in a function that can't fail or if it
fails the failure must be non-fatal.
For time namespaces the relevant functions that fell into this
category were timens_set_vvar_page() and vdso_join_timens(). The
latter could still fail although it didn't need to. This function is
only implemented for vdso_join_timens() in current mainline. As
discussed on-list (cf. [1]), in order to make setns() support time
namespaces when attaching to multiple namespaces at once properly we
changed vdso_join_timens() to always succeed. So vdso_join_timens()
replaces the mmap_write_lock_killable() with mmap_read_lock().
Please note that arm is about to grow vdso support for time namespaces
(possibly this merge window). We've synced on this change and arm64
also uses mmap_read_lock(), i.e. makes vdso_join_timens() a function
that can't fail. Once the changes here and the arm64 changes have
landed, vdso_join_timens() should be turned into a void function so
it's obvious to callers and implementers on other architectures that
the expectation is that it can't fail.
We didn't do this right away because it would've introduced
unnecessary merge conflicts between the two trees for no major gain.
As always, tests included"
[1]: https://lore.kernel.org/lkml/20200611110221.pgd3r5qkjrjmfqa2@wittgenstein
* tag 'threads-v5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
tests: add CLONE_NEWTIME setns tests
nsproxy: support CLONE_NEWTIME with setns()
timens: add timens_commit() helper
timens: make vdso_join_timens() always succeed
Pull execve updates from Eric Biederman:
"During the development of v5.7 I ran into bugs and quality of
implementation issues related to exec that could not be easily fixed
because of the way exec is implemented. So I have been diggin into
exec and cleaning up what I can.
This cycle I have been looking at different ideas and different
implementations to see what is possible to improve exec, and cleaning
the way exec interfaces with in kernel users. Only cleaning up the
interfaces of exec with rest of the kernel has managed to stabalize
and make it through review in time for v5.9-rc1 resulting in 2 sets of
changes this cycle.
- Implement kernel_execve
- Make the user mode driver code a better citizen
With kernel_execve the code size got a little larger as the copying of
parameters from userspace and copying of parameters from userspace is
now separate. The good news is kernel threads no longer need to play
games with set_fs to use exec. Which when combined with the rest of
Christophs set_fs changes should security bugs with set_fs much more
difficult"
* 'exec-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace: (23 commits)
exec: Implement kernel_execve
exec: Factor bprm_stack_limits out of prepare_arg_pages
exec: Factor bprm_execve out of do_execve_common
exec: Move bprm_mm_init into alloc_bprm
exec: Move initialization of bprm->filename into alloc_bprm
exec: Factor out alloc_bprm
exec: Remove unnecessary spaces from binfmts.h
umd: Stop using split_argv
umd: Remove exit_umh
bpfilter: Take advantage of the facilities of struct pid
exit: Factor thread_group_exited out of pidfd_poll
umd: Track user space drivers with struct pid
bpfilter: Move bpfilter_umh back into init data
exec: Remove do_execve_file
umh: Stop calling do_execve_file
umd: Transform fork_usermode_blob into fork_usermode_driver
umd: Rename umd_info.cmdline umd_info.driver_name
umd: For clarity rename umh_info umd_info
umh: Separate the user mode driver and the user mode helper support
umh: Remove call_usermodehelper_setup_file.
...
-----BEGIN PGP SIGNATURE-----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=Xs3M
-----END PGP SIGNATURE-----
Merge tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit updates from Paul Moore:
"Aside from some smaller bug fixes, here are the highlights:
- add a new backlog wait metric to the audit status message, this is
intended to help admins determine how long processes have been
waiting for the audit backlog queue to clear
- generate audit records for nftables configuration changes
- generate CWD audit records for for the relevant LSM audit records"
* tag 'audit-pr-20200803' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: report audit wait metric in audit status reply
audit: purge audit_log_string from the intra-kernel audit API
audit: issue CWD record to accompany LSM_AUDIT_DATA_* records
audit: use the proper gfp flags in the audit_log_nfcfg() calls
audit: remove unused !CONFIG_AUDITSYSCALL __audit_inode* stubs
audit: add gfp parameter to audit_log_nfcfg
audit: log nftables configuration change events
audit: Use struct_size() helper in alloc_chunk
- Improved selftest coverage, timeouts, and reporting
- Add EPOLLHUP support for SECCOMP_RET_USER_NOTIF (Christian Brauner)
- Refactor __scm_install_fd() into __receive_fd() and fix buggy callers
- Introduce "addfd" command for SECCOMP_RET_USER_NOTIF (Sargun Dhillon)
-----BEGIN PGP SIGNATURE-----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=yb55
-----END PGP SIGNATURE-----
Merge tag 'seccomp-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull seccomp updates from Kees Cook:
"There are a bunch of clean ups and selftest improvements along with
two major updates to the SECCOMP_RET_USER_NOTIF filter return:
EPOLLHUP support to more easily detect the death of a monitored
process, and being able to inject fds when intercepting syscalls that
expect an fd-opening side-effect (needed by both container folks and
Chrome). The latter continued the refactoring of __scm_install_fd()
started by Christoph, and in the process found and fixed a handful of
bugs in various callers.
- Improved selftest coverage, timeouts, and reporting
- Add EPOLLHUP support for SECCOMP_RET_USER_NOTIF (Christian Brauner)
- Refactor __scm_install_fd() into __receive_fd() and fix buggy
callers
- Introduce 'addfd' command for SECCOMP_RET_USER_NOTIF (Sargun
Dhillon)"
* tag 'seccomp-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux: (30 commits)
selftests/seccomp: Test SECCOMP_IOCTL_NOTIF_ADDFD
seccomp: Introduce addfd ioctl to seccomp user notifier
fs: Expand __receive_fd() to accept existing fd
pidfd: Replace open-coded receive_fd()
fs: Add receive_fd() wrapper for __receive_fd()
fs: Move __scm_install_fd() to __receive_fd()
net/scm: Regularize compat handling of scm_detach_fds()
pidfd: Add missing sock updates for pidfd_getfd()
net/compat: Add missing sock updates for SCM_RIGHTS
selftests/seccomp: Check ENOSYS under tracing
selftests/seccomp: Refactor to use fixture variants
selftests/harness: Clean up kern-doc for fixtures
seccomp: Use -1 marker for end of mode 1 syscall list
seccomp: Fix ioctl number for SECCOMP_IOCTL_NOTIF_ID_VALID
selftests/seccomp: Rename user_trap_syscall() to user_notif_syscall()
selftests/seccomp: Make kcmp() less required
seccomp: Use pr_fmt
selftests/seccomp: Improve calibration loop
selftests/seccomp: use 90s as timeout
selftests/seccomp: Expand benchmark to per-filter measurements
...
- Prepare for tasklet API modernization (Romain Perier, Allen Pais, Kees Cook)
-----BEGIN PGP SIGNATURE-----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=hb+e
-----END PGP SIGNATURE-----
Merge tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull tasklets API update from Kees Cook:
"These are the infrastructure updates needed to support converting the
tasklet API to something more modern (and hopefully for removal
further down the road).
There is a 300-patch series waiting in the wings to get set out to
subsystem maintainers, but these changes need to be present in the
kernel first. Since this has some treewide changes, I carried this
series for -next instead of paining Thomas with it in -tip, but it's
got his Ack.
This is similar to the timer_struct modernization from a while back,
but not nearly as messy (I hope). :)
- Prepare for tasklet API modernization (Romain Perier, Allen Pais,
Kees Cook)"
* tag 'tasklets-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
tasklet: Introduce new initialization API
treewide: Replace DECLARE_TASKLET() with DECLARE_TASKLET_OLD()
usb: gadget: udc: Avoid tasklet passing a global
- Update URLs for HTTPS scheme where available (Alexander A. Klimov)
- Improve STACKLEAK code generation on x86 (Alexander Popov)
-----BEGIN PGP SIGNATURE-----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=X+DU
-----END PGP SIGNATURE-----
Merge tag 'gcc-plugins-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull gcc plugin updates from Kees Cook:
"Primarily improvements to STACKLEAK from Alexander Popov, along with
some additional cleanups.
- Update URLs for HTTPS scheme where available (Alexander A. Klimov)
- Improve STACKLEAK code generation on x86 (Alexander Popov)"
* tag 'gcc-plugins-v5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
gcc-plugins: Replace HTTP links with HTTPS ones
gcc-plugins/stackleak: Add 'verbose' plugin parameter
gcc-plugins/stackleak: Use asm instrumentation to avoid useless register saving
ARM: vdso: Don't use gcc plugins for building vgettimeofday.c
gcc-plugins/stackleak: Don't instrument itself
- Make the Energy Model cover non-CPU devices (Lukasz Luba).
- Add Ice Lake server idle states table to the intel_idle driver
and eliminate a redundant static variable from it (Chen Yu,
Rafael Wysocki).
- Eliminate all W=1 build warnings from cpufreq (Lee Jones).
- Add support for Sapphire Rapids and for Power Limit 4 to the
Intel RAPL power capping driver (Sumeet Pawnikar, Zhang Rui).
- Fix function name in kerneldoc comments in the idle_inject power
capping driver (Yangtao Li).
- Fix locking issues with cpufreq governors and drop a redundant
"weak" function definition from cpufreq (Viresh Kumar).
- Rearrange cpufreq to register non-modular governors at the
core_initcall level and allow the default cpufreq governor to
be specified in the kernel command line (Quentin Perret).
- Extend, fix and clean up the intel_pstate driver (Srinivas
Pandruvada, Rafael Wysocki):
* Add a new sysfs attribute for disabling/enabling CPU
energy-efficiency optimizations in the processor.
* Make the driver avoid enabling HWP if EPP is not supported.
* Allow the driver to handle numeric EPP values in the sysfs
interface and fix the setting of EPP via sysfs in the active
mode.
* Eliminate a static checker warning and clean up a kerneldoc
comment.
- Clean up some variable declarations in the powernv cpufreq
driver (Wei Yongjun).
- Fix up the ->enter_s2idle callback definition to cover the case
when it points to the same function as ->idle correctly (Neal
Liu).
- Rearrange and clean up the PSCI cpuidle driver (Ulf Hansson).
- Make the PM core emit "changed" uevent when adding/removing the
"wakeup" sysfs attribute of devices (Abhishek Pandit-Subedi).
- Add a helper macro for declaring PM callbacks and use it in the
MMC jz4740 driver (Paul Cercueil).
- Fix white space in some places in the hibernate code and make the
system-wide PM code use "const char *" where appropriate (Xiang
Chen, Alexey Dobriyan).
- Add one more "unsafe" helper macro to the freezer to cover the NFS
use case (He Zhe).
- Change the language in the generic PM domains framework to use
parent/child terminology and clean up a typo and some comment
fromatting in that code (Kees Cook, Geert Uytterhoeven).
- Update the operating performance points OPP framework (Lukasz
Luba, Andrew-sh.Cheng, Valdis Kletnieks):
* Refactor dev_pm_opp_of_register_em() and update related drivers.
* Add a missing function export.
* Allow disabled OPPs in dev_pm_opp_get_freq().
- Update devfreq core and drivers (Chanwoo Choi, Lukasz Luba, Enric
Balletbo i Serra, Dmitry Osipenko, Kieran Bingham, Marc Zyngier):
* Add support for delayed timers to the devfreq core and make the
Samsung exynos5422-dmc driver use it.
* Unify sysfs interface to use "df-" as a prefix in instance names
consistently.
* Fix devfreq_summary debugfs node indentation.
* Add the rockchip,pmu phandle to the rk3399_dmc driver DT
bindings.
* List Dmitry Osipenko as the Tegra devfreq driver maintainer.
* Fix typos in the core devfreq code.
- Update the pm-graph utility to version 5.7 including a number of
fixes related to suspend-to-idle (Todd Brandt).
- Fix coccicheck errors and warnings in the cpupower utility (Shuah
Khan).
- Replace HTTP links with HTTPs ones in multiple places (Alexander
A. Klimov).
-----BEGIN PGP SIGNATURE-----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=8cUO
-----END PGP SIGNATURE-----
Merge tag 'pm-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm
Pull power management updates from Rafael Wysocki:
"The most significant change here is the extension of the Energy Model
to cover non-CPU devices (as well as CPUs) from Lukasz Luba.
There is also some new hardware support (Ice Lake server idle states
table for intel_idle, Sapphire Rapids and Power Limit 4 support in the
RAPL driver), some new functionality in the existing drivers (eg. a
new switch to disable/enable CPU energy-efficiency optimizations in
intel_pstate, delayed timers in devfreq), some assorted fixes (cpufreq
core, intel_pstate, intel_idle) and cleanups (eg. cpuidle-psci,
devfreq), including the elimination of W=1 build warnings from cpufreq
done by Lee Jones.
Specifics:
- Make the Energy Model cover non-CPU devices (Lukasz Luba).
- Add Ice Lake server idle states table to the intel_idle driver and
eliminate a redundant static variable from it (Chen Yu, Rafael
Wysocki).
- Eliminate all W=1 build warnings from cpufreq (Lee Jones).
- Add support for Sapphire Rapids and for Power Limit 4 to the Intel
RAPL power capping driver (Sumeet Pawnikar, Zhang Rui).
- Fix function name in kerneldoc comments in the idle_inject power
capping driver (Yangtao Li).
- Fix locking issues with cpufreq governors and drop a redundant
"weak" function definition from cpufreq (Viresh Kumar).
- Rearrange cpufreq to register non-modular governors at the
core_initcall level and allow the default cpufreq governor to be
specified in the kernel command line (Quentin Perret).
- Extend, fix and clean up the intel_pstate driver (Srinivas
Pandruvada, Rafael Wysocki):
* Add a new sysfs attribute for disabling/enabling CPU
energy-efficiency optimizations in the processor.
* Make the driver avoid enabling HWP if EPP is not supported.
* Allow the driver to handle numeric EPP values in the sysfs
interface and fix the setting of EPP via sysfs in the active
mode.
* Eliminate a static checker warning and clean up a kerneldoc
comment.
- Clean up some variable declarations in the powernv cpufreq driver
(Wei Yongjun).
- Fix up the ->enter_s2idle callback definition to cover the case
when it points to the same function as ->idle correctly (Neal Liu).
- Rearrange and clean up the PSCI cpuidle driver (Ulf Hansson).
- Make the PM core emit "changed" uevent when adding/removing the
"wakeup" sysfs attribute of devices (Abhishek Pandit-Subedi).
- Add a helper macro for declaring PM callbacks and use it in the MMC
jz4740 driver (Paul Cercueil).
- Fix white space in some places in the hibernate code and make the
system-wide PM code use "const char *" where appropriate (Xiang
Chen, Alexey Dobriyan).
- Add one more "unsafe" helper macro to the freezer to cover the NFS
use case (He Zhe).
- Change the language in the generic PM domains framework to use
parent/child terminology and clean up a typo and some comment
fromatting in that code (Kees Cook, Geert Uytterhoeven).
- Update the operating performance points OPP framework (Lukasz Luba,
Andrew-sh.Cheng, Valdis Kletnieks):
* Refactor dev_pm_opp_of_register_em() and update related drivers.
* Add a missing function export.
* Allow disabled OPPs in dev_pm_opp_get_freq().
- Update devfreq core and drivers (Chanwoo Choi, Lukasz Luba, Enric
Balletbo i Serra, Dmitry Osipenko, Kieran Bingham, Marc Zyngier):
* Add support for delayed timers to the devfreq core and make the
Samsung exynos5422-dmc driver use it.
* Unify sysfs interface to use "df-" as a prefix in instance
names consistently.
* Fix devfreq_summary debugfs node indentation.
* Add the rockchip,pmu phandle to the rk3399_dmc driver DT
bindings.
* List Dmitry Osipenko as the Tegra devfreq driver maintainer.
* Fix typos in the core devfreq code.
- Update the pm-graph utility to version 5.7 including a number of
fixes related to suspend-to-idle (Todd Brandt).
- Fix coccicheck errors and warnings in the cpupower utility (Shuah
Khan).
- Replace HTTP links with HTTPs ones in multiple places (Alexander A.
Klimov)"
* tag 'pm-5.9-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (71 commits)
cpuidle: ACPI: fix 'return' with no value build warning
cpufreq: intel_pstate: Fix EPP setting via sysfs in active mode
cpufreq: intel_pstate: Rearrange the storing of new EPP values
intel_idle: Customize IceLake server support
PM / devfreq: Fix the wrong end with semicolon
PM / devfreq: Fix indentaion of devfreq_summary debugfs node
PM / devfreq: Clean up the devfreq instance name in sysfs attr
memory: samsung: exynos5422-dmc: Add module param to control IRQ mode
memory: samsung: exynos5422-dmc: Adjust polling interval and uptreshold
memory: samsung: exynos5422-dmc: Use delayed timer as default
PM / devfreq: Add support delayed timer for polling mode
dt-bindings: devfreq: rk3399_dmc: Add rockchip,pmu phandle
PM / devfreq: tegra: Add Dmitry as a maintainer
PM / devfreq: event: Fix trivial spelling
PM / devfreq: rk3399_dmc: Fix kernel oops when rockchip,pmu is absent
cpuidle: change enter_s2idle() prototype
cpuidle: psci: Prevent domain idlestates until consumers are ready
cpuidle: psci: Convert PM domain to platform driver
cpuidle: psci: Fix error path via converting to a platform driver
cpuidle: psci: Fail cpuidle registration if set OSI mode failed
...
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-08-04
The following pull-request contains BPF updates for your *net-next* tree.
We've added 73 non-merge commits during the last 9 day(s) which contain
a total of 135 files changed, 4603 insertions(+), 1013 deletions(-).
The main changes are:
1) Implement bpf_link support for XDP. Also add LINK_DETACH operation for the BPF
syscall allowing processes with BPF link FD to force-detach, from Andrii Nakryiko.
2) Add BPF iterator for map elements and to iterate all BPF programs for efficient
in-kernel inspection, from Yonghong Song and Alexei Starovoitov.
3) Separate bpf_get_{stack,stackid}() helpers for perf events in BPF to avoid
unwinder errors, from Song Liu.
4) Allow cgroup local storage map to be shared between programs on the same
cgroup. Also extend BPF selftests with coverage, from YiFei Zhu.
5) Add BPF exception tables to ARM64 JIT in order to be able to JIT BPF_PROBE_MEM
load instructions, from Jean-Philippe Brucker.
6) Follow-up fixes on BPF socket lookup in combination with reuseport group
handling. Also add related BPF selftests, from Jakub Sitnicki.
7) Allow to use socket storage in BPF_PROG_TYPE_CGROUP_SOCK-typed programs for
socket create/release as well as bind functions, from Stanislav Fomichev.
8) Fix an info leak in xsk_getsockopt() when retrieving XDP stats via old struct
xdp_statistics, from Peilin Ye.
9) Fix PT_REGS_RC{,_CORE}() macros in libbpf for MIPS arch, from Jerry Crunchtime.
10) Extend BPF kernel test infra with skb->family and skb->{local,remote}_ip{4,6}
fields and allow user space to specify skb->dev via ifindex, from Dmitry Yakunin.
11) Fix a bpftool segfault due to missing program type name and make it more robust
to prevent them in future gaps, from Quentin Monnet.
12) Consolidate cgroup helper functions across selftests and fix a v6 localhost
resolver issue, from John Fastabend.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
- Improve uclamp performance by using a static key for the fast path
- Add the "sched_util_clamp_min_rt_default" sysctl, to optimize for
better power efficiency of RT tasks on battery powered devices.
(The default is to maximize performance & reduce RT latencies.)
- Improve utime and stime tracking accuracy, which had a fixed boundary
of error, which created larger and larger relative errors as the values
become larger. This is now replaced with more precise arithmetics,
using the new mul_u64_u64_div_u64() helper in math64.h.
- Improve the deadline scheduler, such as making it capacity aware
- Improve frequency-invariant scheduling
- Misc cleanups in energy/power aware scheduling
- Add sched_update_nr_running tracepoint to track changes to nr_running
- Documentation additions and updates
- Misc cleanups and smaller fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=PbO7
-----END PGP SIGNATURE-----
Merge tag 'sched-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull scheduler updates from Ingo Molnar:
- Improve uclamp performance by using a static key for the fast path
- Add the "sched_util_clamp_min_rt_default" sysctl, to optimize for
better power efficiency of RT tasks on battery powered devices.
(The default is to maximize performance & reduce RT latencies.)
- Improve utime and stime tracking accuracy, which had a fixed boundary
of error, which created larger and larger relative errors as the
values become larger. This is now replaced with more precise
arithmetics, using the new mul_u64_u64_div_u64() helper in math64.h.
- Improve the deadline scheduler, such as making it capacity aware
- Improve frequency-invariant scheduling
- Misc cleanups in energy/power aware scheduling
- Add sched_update_nr_running tracepoint to track changes to nr_running
- Documentation additions and updates
- Misc cleanups and smaller fixes
* tag 'sched-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (54 commits)
sched/doc: Factorize bits between sched-energy.rst & sched-capacity.rst
sched/doc: Document capacity aware scheduling
sched: Document arch_scale_*_capacity()
arm, arm64: Fix selection of CONFIG_SCHED_THERMAL_PRESSURE
Documentation/sysctl: Document uclamp sysctl knobs
sched/uclamp: Add a new sysctl to control RT default boost value
sched/uclamp: Fix a deadlock when enabling uclamp static key
sched: Remove duplicated tick_nohz_full_enabled() check
sched: Fix a typo in a comment
sched/uclamp: Remove unnecessary mutex_init()
arm, arm64: Select CONFIG_SCHED_THERMAL_PRESSURE
sched: Cleanup SCHED_THERMAL_PRESSURE kconfig entry
arch_topology, sched/core: Cleanup thermal pressure definition
trace/events/sched.h: fix duplicated word
linux/sched/mm.h: drop duplicated words in comments
smp: Fix a potential usage of stale nr_cpus
sched/fair: update_pick_idlest() Select group with lowest group_util when idle_cpus are equal
sched: nohz: stop passing around unused "ticks" parameter.
sched: Better document ttwu()
sched: Add a tracepoint to track rq->nr_running
...
- Add uncore support for Intel Comet Lake
- Add RAPL support for Hygon Fam18h
- Add Intel "IIO stack to PMON mapping" support on Skylake-SP CPUs,
which enumerates per device performance counters via sysfs and enables
the perf stat --iiostat functionality
- Add support for Intel "Architectural LBRs", which generalized the model
specific LBR hardware tracing feature into a model-independent, architected
performance monitoring feature. Usage is mostly seamless to tooling, as the
pre-existing LBR features are kept, but there's a couple of advantages
under the hood, such as faster context-switching, faster LBR reads,
cleaner exposure of LBR features to guest kernels, etc.
( Since architectural LBRs are supported via XSAVE, there's related
changes to the x86 FPU code as well. )
- ftrace/perf updates: Add support to add a text poke event to record changes
to kernel text (i.e. self-modifying code) in order to
support tracers like Intel PT decoding through
jump labels, kprobes and ftrace trampolines.
- Misc cleanups, smaller fixes.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=4pKU
-----END PGP SIGNATURE-----
Merge tag 'perf-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf event updates from Ingo Molnar:
"HW support updates:
- Add uncore support for Intel Comet Lake
- Add RAPL support for Hygon Fam18h
- Add Intel "IIO stack to PMON mapping" support on Skylake-SP CPUs,
which enumerates per device performance counters via sysfs and
enables the perf stat --iiostat functionality
- Add support for Intel "Architectural LBRs", which generalized the
model specific LBR hardware tracing feature into a
model-independent, architected performance monitoring feature.
Usage is mostly seamless to tooling, as the pre-existing LBR
features are kept, but there's a couple of advantages under the
hood, such as faster context-switching, faster LBR reads, cleaner
exposure of LBR features to guest kernels, etc.
( Since architectural LBRs are supported via XSAVE, there's related
changes to the x86 FPU code as well. )
ftrace/perf updates:
- Add support to add a text poke event to record changes to kernel
text (i.e. self-modifying code) in order to support tracers like
Intel PT decoding through jump labels, kprobes and ftrace
trampolines.
Misc cleanups, smaller fixes..."
* tag 'perf-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (47 commits)
perf/x86/rapl: Add Hygon Fam18h RAPL support
kprobes: Remove unnecessary module_mutex locking from kprobe_optimizer()
x86/perf: Fix a typo
perf: <linux/perf_event.h>: drop a duplicated word
perf/x86/intel/lbr: Support XSAVES for arch LBR read
perf/x86/intel/lbr: Support XSAVES/XRSTORS for LBR context switch
x86/fpu/xstate: Add helpers for LBR dynamic supervisor feature
x86/fpu/xstate: Support dynamic supervisor feature for LBR
x86/fpu: Use proper mask to replace full instruction mask
perf/x86: Remove task_ctx_size
perf/x86/intel/lbr: Create kmem_cache for the LBR context data
perf/core: Use kmem_cache to allocate the PMU specific data
perf/core: Factor out functions to allocate/free the task_ctx_data
perf/x86/intel/lbr: Support Architectural LBR
perf/x86/intel/lbr: Factor out intel_pmu_store_lbr
perf/x86/intel/lbr: Factor out rdlbr_all() and wrlbr_all()
perf/x86/intel/lbr: Mark the {rd,wr}lbr_{to,from} wrappers __always_inline
perf/x86/intel/lbr: Unify the stored format of LBR information
perf/x86/intel/lbr: Support LBR_CTL
perf/x86: Expose CPUID enumeration bits for arch LBR
...
- LKMM updates: mostly documentation changes, but also some new litmus tests for atomic ops.
- KCSAN updates: the most important change is that GCC 11 now has all fixes in place
to support KCSAN, so GCC support can be enabled again. Also more annotations.
- futex updates: minor cleanups and simplifications
- seqlock updates: merge preparatory changes/cleanups for the 'associated locks' facilities.
- lockdep updates:
- simplify IRQ trace event handling
- add various new debug checks
- simplify header dependencies, split out <linux/lockdep_types.h>, decouple
lockdep from other low level headers some more
- fix NMI handling
- misc cleanups and smaller fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=3MTT
-----END PGP SIGNATURE-----
Merge tag 'locking-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull locking updates from Ingo Molnar:
- LKMM updates: mostly documentation changes, but also some new litmus
tests for atomic ops.
- KCSAN updates: the most important change is that GCC 11 now has all
fixes in place to support KCSAN, so GCC support can be enabled again.
Also more annotations.
- futex updates: minor cleanups and simplifications
- seqlock updates: merge preparatory changes/cleanups for the
'associated locks' facilities.
- lockdep updates:
- simplify IRQ trace event handling
- add various new debug checks
- simplify header dependencies, split out <linux/lockdep_types.h>,
decouple lockdep from other low level headers some more
- fix NMI handling
- misc cleanups and smaller fixes
* tag 'locking-core-2020-08-03' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (60 commits)
kcsan: Improve IRQ state trace reporting
lockdep: Refactor IRQ trace events fields into struct
seqlock: lockdep assert non-preemptibility on seqcount_t write
lockdep: Add preemption enabled/disabled assertion APIs
seqlock: Implement raw_seqcount_begin() in terms of raw_read_seqcount()
seqlock: Add kernel-doc for seqcount_t and seqlock_t APIs
seqlock: Reorder seqcount_t and seqlock_t API definitions
seqlock: seqcount_t latch: End read sections with read_seqcount_retry()
seqlock: Properly format kernel-doc code samples
Documentation: locking: Describe seqlock design and usage
locking/qspinlock: Do not include atomic.h from qspinlock_types.h
locking/atomic: Move ATOMIC_INIT into linux/types.h
lockdep: Move list.h inclusion into lockdep.h
locking/lockdep: Fix TRACE_IRQFLAGS vs. NMIs
futex: Remove unused or redundant includes
futex: Consistently use fshared as boolean
futex: Remove needless goto's
futex: Remove put_futex_key()
rwsem: fix commas in initialisation
docs: locking: Replace HTTP links with HTTPS ones
...
that helps the debugging of IRQ affinity logic bugs, and fix a memory leak.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
-----BEGIN PGP SIGNATURE-----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=oKU9
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2020-08-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq fixes from Ingo Molnar:
"Fix a recent IRQ affinities regression, add in a missing debugfs
printout that helps the debugging of IRQ affinity logic bugs, and fix
a memory leak"
* tag 'irq-urgent-2020-08-02' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/debugfs: Add missing irqchip flags
genirq/affinity: Make affinity setting if activated opt-in
irqdomain/treewide: Free firmware node after domain removal
- Removal of the tremendously unpopular read_barrier_depends() barrier,
which is a NOP on all architectures apart from Alpha, in favour of
allowing architectures to override READ_ONCE() and do whatever dance
they need to do to ensure address dependencies provide LOAD ->
LOAD/STORE ordering. This work also offers a potential solution if
compilers are shown to convert LOAD -> LOAD address dependencies into
control dependencies (e.g. under LTO), as weakly ordered architectures
will effectively be able to upgrade READ_ONCE() to smp_load_acquire().
The latter case is not used yet, but will be discussed further at LPC.
- Make the MSI/IOMMU input/output ID translation PCI agnostic, augment
the MSI/IOMMU ACPI/OF ID mapping APIs to accept an input ID
bus-specific parameter and apply the resulting changes to the device
ID space provided by the Freescale FSL bus.
- arm64 support for TLBI range operations and translation table level
hints (part of the ARMv8.4 architecture version).
- Time namespace support for arm64.
- Export the virtual and physical address sizes in vmcoreinfo for
makedumpfile and crash utilities.
- CPU feature handling cleanups and checks for programmer errors
(overlapping bit-fields).
- ACPI updates for arm64: disallow AML accesses to EFI code regions and
kernel memory.
- perf updates for arm64.
- Miscellaneous fixes and cleanups, most notably PLT counting
optimisation for module loading, recordmcount fix to ignore
relocations other than R_AARCH64_CALL26, CMA areas reserved for
gigantic pages on 16K and 64K configurations.
- Trivial typos, duplicate words.
-----BEGIN PGP SIGNATURE-----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=mh79
-----END PGP SIGNATURE-----
Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux
Pull arm64 and cross-arch updates from Catalin Marinas:
"Here's a slightly wider-spread set of updates for 5.9.
Going outside the usual arch/arm64/ area is the removal of
read_barrier_depends() series from Will and the MSI/IOMMU ID
translation series from Lorenzo.
The notable arm64 updates include ARMv8.4 TLBI range operations and
translation level hint, time namespace support, and perf.
Summary:
- Removal of the tremendously unpopular read_barrier_depends()
barrier, which is a NOP on all architectures apart from Alpha, in
favour of allowing architectures to override READ_ONCE() and do
whatever dance they need to do to ensure address dependencies
provide LOAD -> LOAD/STORE ordering.
This work also offers a potential solution if compilers are shown
to convert LOAD -> LOAD address dependencies into control
dependencies (e.g. under LTO), as weakly ordered architectures will
effectively be able to upgrade READ_ONCE() to smp_load_acquire().
The latter case is not used yet, but will be discussed further at
LPC.
- Make the MSI/IOMMU input/output ID translation PCI agnostic,
augment the MSI/IOMMU ACPI/OF ID mapping APIs to accept an input ID
bus-specific parameter and apply the resulting changes to the
device ID space provided by the Freescale FSL bus.
- arm64 support for TLBI range operations and translation table level
hints (part of the ARMv8.4 architecture version).
- Time namespace support for arm64.
- Export the virtual and physical address sizes in vmcoreinfo for
makedumpfile and crash utilities.
- CPU feature handling cleanups and checks for programmer errors
(overlapping bit-fields).
- ACPI updates for arm64: disallow AML accesses to EFI code regions
and kernel memory.
- perf updates for arm64.
- Miscellaneous fixes and cleanups, most notably PLT counting
optimisation for module loading, recordmcount fix to ignore
relocations other than R_AARCH64_CALL26, CMA areas reserved for
gigantic pages on 16K and 64K configurations.
- Trivial typos, duplicate words"
Link: http://lkml.kernel.org/r/20200710165203.31284-1-will@kernel.org
Link: http://lkml.kernel.org/r/20200619082013.13661-1-lorenzo.pieralisi@arm.com
* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (82 commits)
arm64: use IRQ_STACK_SIZE instead of THREAD_SIZE for irq stack
arm64/mm: save memory access in check_and_switch_context() fast switch path
arm64: sigcontext.h: delete duplicated word
arm64: ptrace.h: delete duplicated word
arm64: pgtable-hwdef.h: delete duplicated words
bus: fsl-mc: Add ACPI support for fsl-mc
bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver
of/irq: Make of_msi_map_rid() PCI bus agnostic
of/irq: make of_msi_map_get_device_domain() bus agnostic
dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus
of/device: Add input id to of_dma_configure()
of/iommu: Make of_map_rid() PCI agnostic
ACPI/IORT: Add an input ID to acpi_dma_configure()
ACPI/IORT: Remove useless PCI bus walk
ACPI/IORT: Make iort_msi_map_rid() PCI agnostic
ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic
ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC
arm64: enable time namespace support
arm64/vdso: Restrict splitting VVAR VMA
arm64/vdso: Handle faults on timens page
...
-----BEGIN PGP SIGNATURE-----
iQFHBAABCAAxFiEEeOVYVaWZL5900a/pOQOGJssO/ZEFAl8eiUATHHJwcHRAbGlu
dXguaWJtLmNvbQAKCRA5A4Ymyw79kWs8B/4wEWVJGTkjyrMX57/Ew8yRYAJE6JjA
kSONPjElVrPR1pRLYyjyde+zqumkJFhk+41De09J2byL29p7tK8ISNrTwJrIN7n/
dzT73CmuNEjI0rZJxPX+USKFph75FQVvAVOOWs+6fiBFxdUaIsBheVntH7/NsCTk
HFrIjIn5wXFVs5Nh+2cHydvEpOVoUWzjvs+uJIEpHCVCBz6gaYq2dxEmeTquKuz1
k7PZqCqVsyB9iWLqN65/Q+30N8znJwcUl8HAzs5nvPrXLjGxwuEjOxtYYhbdLAfP
OBiIF9J77sZxBlms0WNomDW3Rr5Vlt5nF9oUWpi3AmHNWIuX0GkM4i0C
=V+Kl
-----END PGP SIGNATURE-----
Merge tag 'rm-unicore32' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux
Pull unicore32 removal from Mike Rapoport:
"Remove unicore32 support.
The unicore32 port do not seem maintained for a long time now, there
is no upstream toolchain that can create unicore32 binaries and all
the links to prebuilt toolchains for unicore32 are dead. Even
compilers that were available are not supported by the kernel anymore.
Guenter Roeck says:
"I have stopped building unicore32 images since v4.19 since there is
no available compiler that is still supported by the kernel. I am
surprised that support for it has not been removed from the kernel"
However, it's worth pointing out two things:
- Guan Xuetao is still listed as maintainer and asked for the port to
be kept around the last time Arnd suggested removing it two years
ago. He promised that there would be compiler sources (presumably
llvm), but has not made those available since.
- https://github.com/gxt has patches to linux-4.9 and qemu-2.7, both
released in 2016, with patches dated early 2019. These patches
mainly restore a syscall ABI that was never part of mainline Linux
but apparently used in production. qemu-2.8 removed support for
that ABI and newer kernels (4.19+) can no longer be built with the
old toolchain, so apparently there will not be any future updates
to that git tree"
* tag 'rm-unicore32' of git://git.kernel.org/pub/scm/linux/kernel/git/rppt/linux:
MAINTAINERS: remove "PKUNITY SOC DRIVERS" entry
rtc: remove fb-puv3 driver
video: fbdev: remove fb-puv3 driver
pwm: remove pwm-puv3 driver
input: i8042: remove support for 8042-unicore32io
i2c/buses: remove i2c-puv3 driver
cpufreq: remove unicore32 driver
arch: remove unicore32 port
We found a case of kernel panic on our server. The stack trace is as
follows(omit some irrelevant information):
BUG: kernel NULL pointer dereference, address: 0000000000000080
RIP: 0010:kprobe_ftrace_handler+0x5e/0xe0
RSP: 0018:ffffb512c6550998 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8e9d16eea018 RCX: 0000000000000000
RDX: ffffffffbe1179c0 RSI: ffffffffc0535564 RDI: ffffffffc0534ec0
RBP: ffffffffc0534ec1 R08: ffff8e9d1bbb0f00 R09: 0000000000000004
R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000000
R13: ffff8e9d1f797060 R14: 000000000000bacc R15: ffff8e9ce13eca00
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000080 CR3: 00000008453d0005 CR4: 00000000003606e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
ftrace_ops_assist_func+0x56/0xe0
ftrace_call+0x5/0x34
tcpa_statistic_send+0x5/0x130 [ttcp_engine]
The tcpa_statistic_send is the function being kprobed. After analysis,
the root cause is that the fourth parameter regs of kprobe_ftrace_handler
is NULL. Why regs is NULL? We use the crash tool to analyze the kdump.
crash> dis tcpa_statistic_send -r
<tcpa_statistic_send>: callq 0xffffffffbd8018c0 <ftrace_caller>
The tcpa_statistic_send calls ftrace_caller instead of ftrace_regs_caller.
So it is reasonable that the fourth parameter regs of kprobe_ftrace_handler
is NULL. In theory, we should call the ftrace_regs_caller instead of the
ftrace_caller. After in-depth analysis, we found a reproducible path.
Writing a simple kernel module which starts a periodic timer. The
timer's handler is named 'kprobe_test_timer_handler'. The module
name is kprobe_test.ko.
1) insmod kprobe_test.ko
2) bpftrace -e 'kretprobe:kprobe_test_timer_handler {}'
3) echo 0 > /proc/sys/kernel/ftrace_enabled
4) rmmod kprobe_test
5) stop step 2) kprobe
6) insmod kprobe_test.ko
7) bpftrace -e 'kretprobe:kprobe_test_timer_handler {}'
We mark the kprobe as GONE but not disarm the kprobe in the step 4).
The step 5) also do not disarm the kprobe when unregister kprobe. So
we do not remove the ip from the filter. In this case, when the module
loads again in the step 6), we will replace the code to ftrace_caller
via the ftrace_module_enable(). When we register kprobe again, we will
not replace ftrace_caller to ftrace_regs_caller because the ftrace is
disabled in the step 3). So the step 7) will trigger kernel panic. Fix
this problem by disarming the kprobe when the module is going away.
Link: https://lkml.kernel.org/r/20200728064536.24405-1-songmuchun@bytedance.com
Cc: stable@vger.kernel.org
Fixes: ae6aa16fdc ("kprobes: introduce ftrace based optimization")
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Co-developed-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
I was attempting to use pid filtering with function_graph, but it wasn't
allowing anything to make it through. Turns out ftrace_trace_task
returns false if ftrace_ignore_pid is not-empty, which isn't correct
anymore. We're now setting it to FTRACE_PID_IGNORE if we need to ignore
that pid, otherwise it's set to the pid (which is weird considering the
name) or to FTRACE_PID_TRACE. Fix the check to check for !=
FTRACE_PID_IGNORE. With this we can now use function_graph with pid
filtering.
Link: https://lkml.kernel.org/r/20200725005048.1790-1-josef@toxicpanda.com
Fixes: 717e3f5ebc ("ftrace: Make function trace pid filtering a bit more exact")
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
-----BEGIN PGP SIGNATURE-----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=abJG
-----END PGP SIGNATURE-----
Merge tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block
Pull core block updates from Jens Axboe:
"Good amount of cleanups and tech debt removals in here, and as a
result, the diffstat shows a nice net reduction in code.
- Softirq completion cleanups (Christoph)
- Stop using ->queuedata (Christoph)
- Cleanup bd claiming (Christoph)
- Use check_events, moving away from the legacy media change
(Christoph)
- Use inode i_blkbits consistently (Christoph)
- Remove old unused writeback congestion bits (Christoph)
- Cleanup/unify submission path (Christoph)
- Use bio_uninit consistently, instead of bio_disassociate_blkg
(Christoph)
- sbitmap cleared bits handling (John)
- Request merging blktrace event addition (Jan)
- sysfs add/remove race fixes (Luis)
- blk-mq tag fixes/optimizations (Ming)
- Duplicate words in comments (Randy)
- Flush deferral cleanup (Yufen)
- IO context locking/retry fixes (John)
- struct_size() usage (Gustavo)
- blk-iocost fixes (Chengming)
- blk-cgroup IO stats fixes (Boris)
- Various little fixes"
* tag 'for-5.9/block-20200802' of git://git.kernel.dk/linux-block: (135 commits)
block: blk-timeout: delete duplicated word
block: blk-mq-sched: delete duplicated word
block: blk-mq: delete duplicated word
block: genhd: delete duplicated words
block: elevator: delete duplicated word and fix typos
block: bio: delete duplicated words
block: bfq-iosched: fix duplicated word
iocost_monitor: start from the oldest usage index
iocost: Fix check condition of iocg abs_vdebt
block: Remove callback typedefs for blk_mq_ops
block: Use non _rcu version of list functions for tag_set_list
blk-cgroup: show global disk stats in root cgroup io.stat
blk-cgroup: make iostat functions visible to stat printing
block: improve discard bio alignment in __blkdev_issue_discard()
block: change REQ_OP_ZONE_RESET and REQ_OP_ZONE_RESET_ALL to be odd numbers
block: defer flush request no matter whether we have elevator
block: make blk_timeout_init() static
block: remove retry loop in ioc_release_fn()
block: remove unnecessary ioc nested locking
block: integrate bd_start_claiming into __blkdev_get
...
Pull crypto updates from Herbert Xu:
"API:
- Add support for allocating transforms on a specific NUMA Node
- Introduce the flag CRYPTO_ALG_ALLOCATES_MEMORY for storage users
Algorithms:
- Drop PMULL based ghash on arm64
- Fixes for building with clang on x86
- Add sha256 helper that does the digest in one go
- Add SP800-56A rev 3 validation checks to dh
Drivers:
- Permit users to specify NUMA node in hisilicon/zip
- Add support for i.MX6 in imx-rngc
- Add sa2ul crypto driver
- Add BA431 hwrng driver
- Add Ingenic JZ4780 and X1000 hwrng driver
- Spread IRQ affinity in inside-secure and marvell/cesa"
* 'linus' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6: (157 commits)
crypto: sa2ul - Fix inconsistent IS_ERR and PTR_ERR
hwrng: core - remove redundant initialization of variable ret
crypto: x86/curve25519 - Remove unused carry variables
crypto: ingenic - Add hardware RNG for Ingenic JZ4780 and X1000
dt-bindings: RNG: Add Ingenic RNG bindings.
crypto: caam/qi2 - add module alias
crypto: caam - add more RNG hw error codes
crypto: caam/jr - remove incorrect reference to caam_jr_register()
crypto: caam - silence .setkey in case of bad key length
crypto: caam/qi2 - create ahash shared descriptors only once
crypto: caam/qi2 - fix error reporting for caam_hash_alloc
crypto: caam - remove deadcode on 32-bit platforms
crypto: ccp - use generic power management
crypto: xts - Replace memcpy() invocation with simple assignment
crypto: marvell/cesa - irq balance
crypto: inside-secure - irq balance
crypto: ecc - SP800-56A rev 3 local public key validation
crypto: dh - SP800-56A rev 3 local public key validation
crypto: dh - check validity of Z before export
lib/mpi: Add mpi_sub_ui()
...
High order memory stuff within trace could introduce OOM, use kvzalloc instead.
Please find the bellowing for the call stack we run across in an android system.
The scenario happens when traced_probes is woken up to get a large quantity of
trace even if free memory is even higher than watermark_low.
traced_probes invoked oom-killer: gfp_mask=0x140c0c0(GFP_KERNEL|__GFP_COMP|__GFP_ZERO), nodemask=(null), order=2, oom_score_adj=-1
traced_probes cpuset=system-background mems_allowed=0
CPU: 3 PID: 588 Comm: traced_probes Tainted: G W O 4.14.181 #1
Hardware name: Generic DT based system
(unwind_backtrace) from [<c010d824>] (show_stack+0x20/0x24)
(show_stack) from [<c0b2e174>] (dump_stack+0xa8/0xec)
(dump_stack) from [<c027d584>] (dump_header+0x9c/0x220)
(dump_header) from [<c027cfe4>] (oom_kill_process+0xc0/0x5c4)
(oom_kill_process) from [<c027cb94>] (out_of_memory+0x220/0x310)
(out_of_memory) from [<c02816bc>] (__alloc_pages_nodemask+0xff8/0x13a4)
(__alloc_pages_nodemask) from [<c02a6a1c>] (kmalloc_order+0x30/0x48)
(kmalloc_order) from [<c02a6a64>] (kmalloc_order_trace+0x30/0x118)
(kmalloc_order_trace) from [<c0223d7c>] (tracing_buffers_open+0x50/0xfc)
(tracing_buffers_open) from [<c02e6f58>] (do_dentry_open+0x278/0x34c)
(do_dentry_open) from [<c02e70d0>] (vfs_open+0x50/0x70)
(vfs_open) from [<c02f7c24>] (path_openat+0x5fc/0x169c)
(path_openat) from [<c02f75c4>] (do_filp_open+0x94/0xf8)
(do_filp_open) from [<c02e7650>] (do_sys_open+0x168/0x26c)
(do_sys_open) from [<c02e77bc>] (SyS_openat+0x34/0x38)
(SyS_openat) from [<c0108bc0>] (ret_fast_syscall+0x0/0x28)
Link: https://lkml.kernel.org/r/1596155265-32365-1-git-send-email-zhaoyang.huang@unisoc.com
Signed-off-by: Zhaoyang Huang <zhaoyang.huang@unisoc.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
- Add infrastructure to allow DT irqchip platform drivers to
be built as modules
- Allow qcom-pdc, mtk-cirq and mtk-sysirq to be built as module
- Fix ACPI probing to avoid abusing function pointer casting
- Allow bcm7120-l2 and brcmstb-l2 to be used as wake-up sources
- Teach NXP's IMX INTMUX some power management
- Allow stm32-exti to be used as a hierarchical irqchip
- Let stm32-exti use the hw spinlock API in its full glory
- A couple of GICv4.1 fixes
- Tons of cleanups (mtk-sysirq, aic5, bcm7038-l1, imx-intmux,
brcmstb-l2, ativic32, ti-sci-inta, lonsoon, MIPS GIC, GICv3)
-----BEGIN PGP SIGNATURE-----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=hgPS
-----END PGP SIGNATURE-----
Merge tag 'irqchip-5.9' of git://git.kernel.org/pub/scm/linux/kernel/git/maz/arm-platforms into irq/core
Pull irqchip updates from Marc Zyngier:
- Add infrastructure to allow DT irqchip platform drivers to
be built as modules
- Allow qcom-pdc, mtk-cirq and mtk-sysirq to be built as module
- Fix ACPI probing to avoid abusing function pointer casting
- Allow bcm7120-l2 and brcmstb-l2 to be used as wake-up sources
- Teach NXP's IMX INTMUX some power management
- Allow stm32-exti to be used as a hierarchical irqchip
- Let stm32-exti use the hw spinlock API in its full glory
- A couple of GICv4.1 fixes
- Tons of cleanups (mtk-sysirq, aic5, bcm7038-l1, imx-intmux,
brcmstb-l2, ativic32, ti-sci-inta, lonsoon, MIPS GIC, GICv3)
* pm-sleep:
PM: sleep: spread "const char *" correctness
PM: hibernate: fix white space in a few places
freezer: Add unsafe version of freezable_schedule_timeout_interruptible() for NFS
PM: sleep: core: Emit changed uevent on wakeup_sysfs_add/remove
* pm-domains:
PM: domains: Restore comment indentation for generic_pm_domain.child_links
PM: domains: Fix up terminology with parent/child
* powercap:
powercap: Add Power Limit4 support
powercap: idle_inject: Replace play_idle() with play_idle_precise() in comments
powercap: intel_rapl: add support for Sapphire Rapids
* pm-tools:
pm-graph v5.7 - important s2idle fixes
cpupower: Replace HTTP links with HTTPS ones
cpupower: Fix NULL but dereferenced coccicheck errors
cpupower: Fix comparing pointer to 0 coccicheck warns
* pm-cpufreq: (24 commits)
cpufreq: intel_pstate: Fix EPP setting via sysfs in active mode
cpufreq: intel_pstate: Rearrange the storing of new EPP values
cpufreq: intel_pstate: Avoid enabling HWP if EPP is not supported
cpufreq: intel_pstate: Clean up aperf_mperf_shift description
cpufreq: powernv: Make some symbols static
cpufreq: amd_freq_sensitivity: Mark sometimes used ID structs as __maybe_unused
cpufreq: intel_pstate: Supply struct attribute description for get_aperf_mperf_shift()
cpufreq: pcc-cpufreq: Mark sometimes used ID structs as __maybe_unused
cpufreq: powernow-k8: Mark 'hi' and 'lo' dummy variables as __always_unused
cpufreq: acpi-cpufreq: Mark sometimes used ID structs as __maybe_unused
cpufreq: acpi-cpufreq: Mark 'dummy' variable as __always_unused
cpufreq: powernv-cpufreq: Fix a bunch of kerneldoc related issues
cpufreq: pasemi: Include header file for {check,restore}_astate prototypes
cpufreq: cpufreq_governor: Demote store_sampling_rate() header to standard comment block
cpufreq: cpufreq: Demote lots of function headers unworthy of kerneldoc status
cpufreq: freq_table: Demote obvious misuse of kerneldoc to standard comment blocks
cpufreq: Replace HTTP links with HTTPS ones
cpufreq: intel_pstate: Fix static checker warning for epp variable
cpufreq: Remove the weakly defined cpufreq_default_governor()
cpufreq: Specify default governor on command line
...
* pm-em:
OPP: refactor dev_pm_opp_of_register_em() and update related drivers
Documentation: power: update Energy Model description
PM / EM: change name of em_pd_energy to em_cpu_energy
PM / EM: remove em_register_perf_domain
PM / EM: add support for other devices than CPUs in Energy Model
PM / EM: update callback structure and add device pointer
PM / EM: introduce em_dev_register_perf_domain function
PM / EM: change naming convention from 'capacity' to 'performance'
* pm-core:
mmc: jz4740: Use pm_ptr() macro
PM: Make *_DEV_PM_OPS macros use __maybe_unused
PM: core: introduce pm_ptr() macro
Add LINK_DETACH command to force-detach bpf_link without destroying it. It has
the same behavior as auto-detaching of bpf_link due to cgroup dying for
bpf_cgroup_link or net_device being destroyed for bpf_xdp_link. In such case,
bpf_link is still a valid kernel object, but is defuncts and doesn't hold BPF
program attached to corresponding BPF hook. This functionality allows users
with enough access rights to manually force-detach attached bpf_link without
killing respective owner process.
This patch implements LINK_DETACH for cgroup, xdp, and netns links, mostly
re-using existing link release handling code.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Song Liu <songliubraving@fb.com>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20200731182830.286260-2-andriin@fb.com
Pull networking fixes from David Miller:
1) Encap offset calculation is incorrect in esp6, from Sabrina Dubroca.
2) Better parameter validation in pfkey_dump(), from Mark Salyzyn.
3) Fix several clang issues on powerpc in selftests, from Tanner Love.
4) cmsghdr_from_user_compat_to_kern() uses the wrong length, from Al
Viro.
5) Out of bounds access in mlx5e driver, from Raed Salem.
6) Fix transfer buffer memleak in lan78xx, from Johan Havold.
7) RCU fixups in rhashtable, from Herbert Xu.
8) Fix ipv6 nexthop refcnt leak, from Xiyu Yang.
9) vxlan FDB dump must be done under RCU, from Ido Schimmel.
10) Fix use after free in mlxsw, from Ido Schimmel.
11) Fix map leak in HASH_OF_MAPS bpf code, from Andrii Nakryiko.
12) Fix bug in mac80211 Tx ack status reporting, from Vasanthakumar
Thiagarajan.
13) Fix memory leaks in IPV6_ADDRFORM code, from Cong Wang.
14) Fix bpf program reference count leaks in mlx5 during
mlx5e_alloc_rq(), from Xin Xiong.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (86 commits)
vxlan: fix memleak of fdb
rds: Prevent kernel-infoleak in rds_notify_queue_get()
net/sched: The error lable position is corrected in ct_init_module
net/mlx5e: fix bpf_prog reference count leaks in mlx5e_alloc_rq
net/mlx5e: E-Switch, Specify flow_source for rule with no in_port
net/mlx5e: E-Switch, Add misc bit when misc fields changed for mirroring
net/mlx5e: CT: Support restore ipv6 tunnel
net: gemini: Fix missing clk_disable_unprepare() in error path of gemini_ethernet_port_probe()
ionic: unlock queue mutex in error path
atm: fix atm_dev refcnt leaks in atmtcp_remove_persistent
net: ethernet: mtk_eth_soc: fix MTU warnings
net: nixge: fix potential memory leak in nixge_probe()
devlink: ignore -EOPNOTSUPP errors on dumpit
rxrpc: Fix race between recvmsg and sendmsg on immediate call failure
MAINTAINERS: Replace Thor Thayer as Altera Triple Speed Ethernet maintainer
selftests/bpf: fix netdevsim trap_flow_action_cookie read
ipv6: fix memory leaks on IPV6_ADDRFORM path
net/bpfilter: Initialize pos in __bpfilter_process_sockopt
igb: reinit_locked() should be called with rtnl_lock
e1000e: continue to init PHY even when failed to disable ULP
...
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXyXDTQAKCRCRxhvAZXjc
olxlAQDCiyWstd8pmtyX4vuaoyDZ6re6P/TCr3mzr6tQyux/zgD/chlfAvJdyzk8
2Tw44odp3gF5EfzF+5wx2whZZPfVrQY=
=Hv2c
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2020-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull thread fix from Christian Brauner:
"A simple spelling fix for dequeue_synchronous_signal()"
* tag 'for-linus-2020-08-01' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
signal: fix typo in dequeue_synchronous_signal()
Pull v5.9 KCSAN bits from Paul E. McKenney.
Perhaps the most important change is that GCC 11 now has all fixes in place
to support KCSAN, so GCC support can be enabled again.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Rather that hide their purpose in some dark, damp corner of Documentation/,
add some documentation to the default implementations.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200731192016.7484-2-valentin.schneider@arm.com
Daniel Borkmann says:
====================
pull-request: bpf 2020-07-31
The following pull-request contains BPF updates for your *net* tree.
We've added 5 non-merge commits during the last 21 day(s) which contain
a total of 5 files changed, 126 insertions(+), 18 deletions(-).
The main changes are:
1) Fix a map element leak in HASH_OF_MAPS map type, from Andrii Nakryiko.
2) Fix a NULL pointer dereference in __btf_resolve_helper_id() when no
btf_vmlinux is available, from Peilin Ye.
3) Init pos variable in __bpfilter_process_sockopt(), from Christoph Hellwig.
4) Fix a cgroup sockopt verifier test by specifying expected attach type,
from Jean-Philippe Brucker.
Note that when net gets merged into net-next later on, there is a small
merge conflict in kernel/bpf/btf.c between commit 5b801dfb7f ("bpf: Fix
NULL pointer dereference in __btf_resolve_helper_id()") from the bpf tree
and commit 138b9a0511 ("bpf: Remove btf_id helpers resolving") from the
net-next tree.
Resolve as follows: remove the old hunk with the __btf_resolve_helper_id()
function. Change the btf_resolve_helper_id() so it actually tests for a
NULL btf_vmlinux and bails out:
int btf_resolve_helper_id(struct bpf_verifier_log *log,
const struct bpf_func_proto *fn, int arg)
{
int id;
if (fn->arg_type[arg] != ARG_PTR_TO_BTF_ID || !btf_vmlinux)
return -EINVAL;
id = fn->btf_id[arg];
if (!id || id > btf_vmlinux->nr_types)
return -EINVAL;
return id;
}
Let me know if you run into any others issues (CC'ing Jiri Olsa so he's in
the loop with regards to merge conflict resolution).
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
* for-next/misc:
: Miscellaneous fixes and cleanups
arm64: use IRQ_STACK_SIZE instead of THREAD_SIZE for irq stack
arm64/mm: save memory access in check_and_switch_context() fast switch path
recordmcount: only record relocation of type R_AARCH64_CALL26 on arm64.
arm64: Reserve HWCAP2_MTE as (1 << 18)
arm64/entry: deduplicate SW PAN entry/exit routines
arm64: s/AMEVTYPE/AMEVTYPER
arm64/hugetlb: Reserve CMA areas for gigantic pages on 16K and 64K configs
arm64: stacktrace: Move export for save_stack_trace_tsk()
smccc: Make constants available to assembly
arm64/mm: Redefine CONT_{PTE, PMD}_SHIFT
arm64/defconfig: Enable CONFIG_KEXEC_FILE
arm64: Document sysctls for emulated deprecated instructions
arm64/panic: Unify all three existing notifier blocks
arm64/module: Optimize module load time by optimizing PLT counting
* for-next/vmcoreinfo:
: Export the virtual and physical address sizes in vmcoreinfo
arm64/crash_core: Export TCR_EL1.T1SZ in vmcoreinfo
crash_core, vmcoreinfo: Append 'MAX_PHYSMEM_BITS' to vmcoreinfo
* for-next/cpufeature:
: CPU feature handling cleanups
arm64/cpufeature: Validate feature bits spacing in arm64_ftr_regs[]
arm64/cpufeature: Replace all open bits shift encodings with macros
arm64/cpufeature: Add remaining feature bits in ID_AA64MMFR2 register
arm64/cpufeature: Add remaining feature bits in ID_AA64MMFR1 register
arm64/cpufeature: Add remaining feature bits in ID_AA64MMFR0 register
* for-next/acpi:
: ACPI updates for arm64
arm64/acpi: disallow writeable AML opregion mapping for EFI code regions
arm64/acpi: disallow AML memory opregions to access kernel memory
* for-next/perf:
: perf updates for arm64
arm64: perf: Expose some new events via sysfs
tools headers UAPI: Update tools's copy of linux/perf_event.h
arm64: perf: Add cap_user_time_short
perf: Add perf_event_mmap_page::cap_user_time_short ABI
arm64: perf: Only advertise cap_user_time for arch_timer
arm64: perf: Implement correct cap_user_time
time/sched_clock: Use raw_read_seqcount_latch()
sched_clock: Expose struct clock_read_data
arm64: perf: Correct the event index in sysfs
perf/smmuv3: To simplify code for ioremap page in pmcg
* for-next/timens:
: Time namespace support for arm64
arm64: enable time namespace support
arm64/vdso: Restrict splitting VVAR VMA
arm64/vdso: Handle faults on timens page
arm64/vdso: Add time namespace page
arm64/vdso: Zap vvar pages when switching to a time namespace
arm64/vdso: use the fault callback to map vvar pages
* for-next/msi-iommu:
: Make the MSI/IOMMU input/output ID translation PCI agnostic, augment the
: MSI/IOMMU ACPI/OF ID mapping APIs to accept an input ID bus-specific parameter
: and apply the resulting changes to the device ID space provided by the
: Freescale FSL bus
bus: fsl-mc: Add ACPI support for fsl-mc
bus/fsl-mc: Refactor the MSI domain creation in the DPRC driver
of/irq: Make of_msi_map_rid() PCI bus agnostic
of/irq: make of_msi_map_get_device_domain() bus agnostic
dt-bindings: arm: fsl: Add msi-map device-tree binding for fsl-mc bus
of/device: Add input id to of_dma_configure()
of/iommu: Make of_map_rid() PCI agnostic
ACPI/IORT: Add an input ID to acpi_dma_configure()
ACPI/IORT: Remove useless PCI bus walk
ACPI/IORT: Make iort_msi_map_rid() PCI agnostic
ACPI/IORT: Make iort_get_device_domain IRQ domain agnostic
ACPI/IORT: Make iort_match_node_callback walk the ACPI namespace for NC
* for-next/trivial:
: Trivial fixes
arm64: sigcontext.h: delete duplicated word
arm64: ptrace.h: delete duplicated word
arm64: pgtable-hwdef.h: delete duplicated words
Conflicts:
arch/arm/include/asm/percpu.h
As Stephen Rothwell noted, there's a conflict between this commit
in locking/core:
a21ee6055c ("lockdep: Change hardirq{s_enabled,_context} to per-cpu variables")
and this fresh upstream commit:
aa54ea903a ("ARM: percpu.h: fix build error")
a21ee6055c is a simpler solution to the dependency problem and doesn't
further increase header hell - so this conflict resolution effectively
reverts aa54ea903a and uses the a21ee6055c solution.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
To improve the general usefulness of the IRQ state trace events with
KCSAN enabled, save and restore the trace information when entering and
exiting the KCSAN runtime as well as when generating a KCSAN report.
Without this, reporting the IRQ trace events (whether via a KCSAN report
or outside of KCSAN via a lockdep report) is rather useless due to
continuously being touched by KCSAN. This is because if KCSAN is
enabled, every instrumented memory access causes changes to IRQ trace
events (either by KCSAN disabling/enabling interrupts or taking
report_lock when generating a report).
Before "lockdep: Prepare for NMI IRQ state tracking", KCSAN avoided
touching the IRQ trace events via raw_local_irq_save/restore() and
lockdep_off/on().
Fixes: 248591f5d2 ("kcsan: Make KCSAN compatible with new IRQ state tracking")
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200729110916.3920464-2-elver@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Refactor the IRQ trace events fields, used for printing information
about the IRQ trace events, into a separate struct 'irqtrace_events'.
This improves readability by separating the information only used in
reporting, as well as enables (simplified) storing/restoring of
irqtrace_events snapshots.
No functional change intended.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200729110916.3920464-1-elver@google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This comment describes the behaviour before commit 2a820bf749
("tracing: Use percpu stack trace buffer more intelligently"). Since
that commit, interrupts and NMIs do use the per-cpu stacks so the
comment is no longer correct. Remove it.
(Note that the FTRACE_STACK_SIZE mentioned in the comment has never
existed, it probably should have said FTRACE_STACK_ENTRIES.)
Link: https://lkml.kernel.org/r/20200727092840.18659-1-vincent.whitchurch@axis.com
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When inserting a module, we find all ftrace_ops referencing it on the
ftrace_ops_list. But FTRACE_OPS_FL_DIRECT and FTRACE_OPS_FL_IPMODIFY
flags are special, and should not be set automatically. So warn and
skip ftrace_ops that have these two flags set and adding new code.
Also check if only one ftrace_ops references the module, in which case
we can use a trampoline as an optimization.
Link: https://lkml.kernel.org/r/20200728180554.65203-2-zhouchengming@bytedance.com
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
When module loaded and enabled, we will use __ftrace_replace_code
for module if any ftrace_ops referenced it found. But we will get
wrong ftrace_addr for module rec in ftrace_get_addr_new, because
rec->flags has not been setup correctly. It can cause the callback
function of a ftrace_ops has FTRACE_OPS_FL_SAVE_REGS to be called
with pt_regs set to NULL.
So setup correct FTRACE_FL_REGS flags for rec when we call
referenced_filters to find ftrace_ops references it.
Link: https://lkml.kernel.org/r/20200728180554.65203-1-zhouchengming@bytedance.com
Cc: stable@vger.kernel.org
Fixes: 8c4f3c3fa9 ("ftrace: Check module functions being traced on reload")
Signed-off-by: Chengming Zhou <zhouchengming@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
In calculation of the cpu mask for the hwlat kernel thread, the wrong
cpu mask is used instead of the tracing_cpumask, this causes the
tracing/tracing_cpumask useless for hwlat tracer. Fixes it.
Link: https://lkml.kernel.org/r/20200730082318.42584-2-haokexin@gmail.com
Cc: Ingo Molnar <mingo@redhat.com>
Cc: stable@vger.kernel.org
Fixes: 0330f7aa8e ("tracing: Have hwlat trace migrate across tracing_cpumask CPUs")
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
We have set 'current_mask' to '&save_cpumask' in its declaration,
so there is no need to assign again.
Link: https://lkml.kernel.org/r/20200730082318.42584-1-haokexin@gmail.com
Signed-off-by: Kevin Hao <haokexin@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Newline characters are added in two verifier error messages,
refactored in Commit afbf21dce6 ("bpf: Support readonly/readwrite
buffers in verifier"). This way, they do not mix with
messages afterwards.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200728221801.1090349-1-yhs@fb.com
Nowadays, modern kernel subsystems that use callbacks pass the data
structure associated with a given callback as argument to the callback.
The tasklet subsystem remains one which passes an arbitrary unsigned
long to the callback function. This has several problems:
- This keeps an extra field for storing the argument in each tasklet
data structure, it bloats the tasklet_struct structure with a redundant
.data field
- No type checking can be performed on this argument. Instead of
using container_of() like other callback subsystems, it forces callbacks
to do explicit type cast of the unsigned long argument into the required
object type.
- Buffer overflows can overwrite the .func and the .data field, so
an attacker can easily overwrite the function and its first argument
to whatever it wants.
Add a new tasklet initialization API, via DECLARE_TASKLET() and
tasklet_setup(), which will replace the existing ones.
This work is greatly inspired by the timer_struct conversion series,
see commit e99e88a9d2 ("treewide: setup_timer() -> timer_setup()")
To avoid problems with both -Wcast-function-type (which is enabled in
the kernel via -Wextra is several subsystems), and with mismatched
function prototypes when build with Control Flow Integrity enabled,
this adds the "use_callback" member to let the tasklet caller choose
which union member to call through. Once all old API uses are removed,
this and the .data member will be removed as well. (On 64-bit this does
not grow the struct size as the new member fills the hole after atomic_t,
which is also "int" sized.)
Signed-off-by: Romain Perier <romain.perier@gmail.com>
Co-developed-by: Allen Pais <allen.lkml@gmail.com>
Signed-off-by: Allen Pais <allen.lkml@gmail.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
This converts all the existing DECLARE_TASKLET() (and ...DISABLED)
macros with DECLARE_TASKLET_OLD() in preparation for refactoring the
tasklet callback type. All existing DECLARE_TASKLET() users had a "0"
data argument, it has been removed here as well.
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Kees Cook <keescook@chromium.org>
Fix HASH_OF_MAPS bug of not putting inner map pointer on bpf_map_elem_update()
operation. This is due to per-cpu extra_elems optimization, which bypassed
free_htab_elem() logic doing proper clean ups. Make sure that inner map is put
properly in optimized case as well.
Fixes: 8c290e60fa ("bpf: fix hashmap extra_elems logic")
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/20200729040913.2815687-1-andriin@fb.com
-----BEGIN PGP SIGNATURE-----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=zLU9
-----END PGP SIGNATURE-----
Merge tag 'audit-pr-20200729' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit
Pull audit fixes from Paul Moore:
"One small audit fix that you can hopefully merge before v5.8 is
released. Unfortunately it is a revert of a patch that went in during
the v5.7 window and we just recently started to see some bug reports
relating to that commit.
We are working on a proper fix, but I'm not yet clear on when that
will be ready and we need to fix the v5.7 kernels anyway, so in the
interest of time a revert seemed like the best solution right now"
* tag 'audit-pr-20200729' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
revert: 1320a4052e ("audit: trigger accompanying records when no rules present")
This modifies the first 32 bits out of the 128 bits of a random CPU's
net_rand_state on interrupt or CPU activity to complicate remote
observations that could lead to guessing the network RNG's internal
state.
Note that depending on some network devices' interrupt rate moderation
or binding, this re-seeding might happen on every packet or even almost
never.
In addition, with NOHZ some CPUs might not even get timer interrupts,
leaving their local state rarely updated, while they are running
networked processes making use of the random state. For this reason, we
also perform this update in update_process_times() in order to at least
update the state when there is user or system activity, since it's the
only case we care about.
Reported-by: Amit Klein <aksecurity@gmail.com>
Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Eric Dumazet <edumazet@google.com>
Cc: "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Willy Tarreau <w@1wt.eu>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
A sequence counter write side critical section must be protected by some
form of locking to serialize writers. A plain seqcount_t does not
contain the information of which lock must be held when entering a write
side critical section.
Use the new seqcount_raw_spinlock_t data type, which allows to associate
a raw spinlock with the sequence counter. This enables lockdep to verify
that the raw spinlock used for writer serialization is held when the
write side critical section is entered.
If lockdep is disabled this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-25-a.darwish@linutronix.de
A sequence counter write side critical section must be protected by some
form of locking to serialize writers. A plain seqcount_t does not
contain the information of which lock must be held when entering a write
side critical section.
Use the new seqcount_raw_spinlock_t data type, which allows to associate
a raw spinlock with the sequence counter. This enables lockdep to verify
that the raw spinlock used for writer serialization is held when the
write side critical section is entered.
If lockdep is disabled this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-18-a.darwish@linutronix.de
A sequence counter write side critical section must be protected by some
form of locking to serialize writers. A plain seqcount_t does not
contain the information of which lock must be held when entering a write
side critical section.
Use the new seqcount_spinlock_t data type, which allows to associate a
spinlock with the sequence counter. This enables lockdep to verify that
the spinlock used for writer serialization is held when the write side
critical section is entered.
If lockdep is disabled this lock association is compiled out and has
neither storage size nor runtime overhead.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200720155530.1173732-14-a.darwish@linutronix.de
Unfortunately the commit listed in the subject line above failed
to ensure that the task's audit_context was properly initialized/set
before enabling the "accompanying records". Depending on the
situation, the resulting audit_context could have invalid values in
some of it's fields which could cause a kernel panic/oops when the
task/syscall exists and the audit records are generated.
We will revisit the original patch, with the necessary fixes, in a
future kernel but right now we just want to fix the kernel panic
with the least amount of added risk.
Cc: stable@vger.kernel.org
Fixes: 1320a4052e ("audit: trigger accompanying records when no rules present")
Reported-by: j2468h@googlemail.com
Signed-off-by: Paul Moore <paul@paul-moore.com>
Some architectures may have special memory regions, within the given
memory range, which can't be used for the buffer in a kexec segment.
Implement weak arch_kexec_locate_mem_hole() definition which arch code
may override, to take care of special regions, while trying to locate
a memory hole.
Also, add the missing declarations for arch overridable functions and
and drop the __weak descriptors in the declarations to avoid non-weak
definitions from becoming weak.
Signed-off-by: Hari Bathini <hbathini@linux.ibm.com>
Tested-by: Pingfan Liu <piliu@redhat.com>
Reviewed-by: Thiago Jung Bauermann <bauerman@linux.ibm.com>
Acked-by: Dave Young <dyoung@redhat.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/159602273603.575379.17665852963340380839.stgit@hbathini
RT tasks by default run at the highest capacity/performance level. When
uclamp is selected this default behavior is retained by enforcing the
requested uclamp.min (p->uclamp_req[UCLAMP_MIN]) of the RT tasks to be
uclamp_none(UCLAMP_MAX), which is SCHED_CAPACITY_SCALE; the maximum
value.
This is also referred to as 'the default boost value of RT tasks'.
See commit 1a00d99997 ("sched/uclamp: Set default clamps for RT tasks").
On battery powered devices, it is desired to control this default
(currently hardcoded) behavior at runtime to reduce energy consumed by
RT tasks.
For example, a mobile device manufacturer where big.LITTLE architecture
is dominant, the performance of the little cores varies across SoCs, and
on high end ones the big cores could be too power hungry.
Given the diversity of SoCs, the new knob allows manufactures to tune
the best performance/power for RT tasks for the particular hardware they
run on.
They could opt to further tune the value when the user selects
a different power saving mode or when the device is actively charging.
The runtime aspect of it further helps in creating a single kernel image
that can be run on multiple devices that require different tuning.
Keep in mind that a lot of RT tasks in the system are created by the
kernel. On Android for instance I can see over 50 RT tasks, only
a handful of which created by the Android framework.
To control the default behavior globally by system admins and device
integrator, introduce the new sysctl_sched_uclamp_util_min_rt_default
to change the default boost value of the RT tasks.
I anticipate this to be mostly in the form of modifying the init script
of a particular device.
To avoid polluting the fast path with unnecessary code, the approach
taken is to synchronously do the update by traversing all the existing
tasks in the system. This could race with a concurrent fork(), which is
dealt with by introducing sched_post_fork() function which will ensure
the racy fork will get the right update applied.
Tested on Juno-r2 in combination with the RT capacity awareness [1].
By default an RT task will go to the highest capacity CPU and run at the
maximum frequency, which is particularly energy inefficient on high end
mobile devices because the biggest core[s] are 'huge' and power hungry.
With this patch the RT task can be controlled to run anywhere by
default, and doesn't cause the frequency to be maximum all the time.
Yet any task that really needs to be boosted can easily escape this
default behavior by modifying its requested uclamp.min value
(p->uclamp_req[UCLAMP_MIN]) via sched_setattr() syscall.
[1] 804d402fb6: ("sched/rt: Make RT capacity-aware")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200716110347.19553-2-qais.yousef@arm.com
The following splat was caught when setting uclamp value of a task:
BUG: sleeping function called from invalid context at ./include/linux/percpu-rwsem.h:49
cpus_read_lock+0x68/0x130
static_key_enable+0x1c/0x38
__sched_setscheduler+0x900/0xad8
Fix by ensuring we enable the key outside of the critical section in
__sched_setscheduler()
Fixes: 46609ce227 ("sched/uclamp: Protect uclamp fast path code with static key")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200716110347.19553-4-qais.yousef@arm.com
One module user of sched_setscheduler() was overlooked and is
obviously causing build failures.
Convert ring_buffer_benchmark to use sched_set_fifo_low() when fifo==1
and sched_set_fifo() when fifo==2. This is a bit of an abuse, but it
makes the thing 'work' again.
Specifically, it enables all combinations that were previously
possible:
producer higher than consumer
consumer higher than producer
Fixes: 616d91b68c ("sched: Remove sched_setscheduler*() EXPORTs")
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lkml.kernel.org/r/20200720214918.GM5523@worktop.programming.kicks-ass.net
Abstract platform specific mechanics for nvdimm firmware activation
behind a handful of generic ops. At the bus level ->activate_state()
indicates the unified state (idle, busy, armed) of all DIMMs on the bus,
and ->capability() indicates the system state expectations for activate.
At the DIMM level ->activate_state() indicates the per-DIMM state,
->activate_result() indicates the outcome of the last activation
attempt, and ->arm() attempts to transition the DIMM from 'idle' to
'armed'.
A new hibernate_quiet_exec() facility is added to support firmware
activation in an OS defined system quiesce state. It leverages the fact
that the hibernate-freeze state wants to assert that a memory
hibernation snapshot can be taken. This is in contrast to a platform
firmware defined quiesce state that may forcefully quiet the memory
controller independent of whether an individual device-driver properly
supports hibernate-freeze.
The libnvdimm sysfs interface is extended to support detection of a
firmware activate capability. The mechanism supports enumeration and
triggering of firmware activate, optionally in the
hibernate_quiet_exec() context.
[rafael: hibernate_quiet_exec() proposal]
[vishal: fix up sparse warning, grammar in Documentation/]
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Len Brown <len.brown@intel.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Co-developed-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
Entire net/core subsystem is not built without CONFIG_NET. linux/netdevice.h
just assumes that it's always there, so the easiest way to fix this is to
conditionally compile out bpf_xdp_link_attach() use in bpf/syscall.c.
Fixes: aa8d3a716b ("bpf, xdp: Add bpf_link-based XDP attachment API")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Acked-by: Song Liu <songliubraving@fb.com>
Link: https://lore.kernel.org/bpf/20200728190527.110830-1-andriin@fb.com
For bitmasks printing values in hex is more convenient.
Prefix with `0x` to make it clear, that it’s a hex value, and pad it
out.
Using the helper for `amdgpu.ppfeaturemask`, it will look like below.
Before:
$ more /sys/module/amdgpu/parameters/ppfeaturemask
4294950911
After:
$ more /sys/module/amdgpu/parameters/ppfeaturemask
0xffffbfff
Cc: linux-kernel@vger.kernel.org
Cc: amd-gfx@lists.freedesktop.org
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://patchwork.freedesktop.org/patch/374726/
The second and third arguments are aligned with tabs, so do the same for
the fourth.
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Paul Menzel <pmenzel@molgen.mpg.de>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Christian König <christian.koenig@amd.com>
Link: https://lore.kernel.org/patchwork/patch/1267600/
Split out a cma_alloc_aligned helper to deal with the "interesting"
calling conventions for cma_alloc, which then allows to the main
function to be written straight forward. This also takes advantage
of the fact that NULL dev arguments have been gone from the DMA API
for a while.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Nicolin Chen <nicoleotsuka@gmail.com>
Reviewed-by: Barry Song <song.bao.hua@hisilicon.com>
In sched_update_tick_dependency() there's two calls that check
whether nohz_full is enabled: tick_nohz_full_cpu() does it
implicitly, while there's also an explicit call to tick_nohz_full_enabled().
Remove the duplicated, open coded check.
[ mingo: Amended the changelog. ]
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/1595935075-14223-1-git-send-email-linmiaohe@huawei.com
Since we already lock both kprobe_mutex and text_mutex in the optimizer,
text will not be changed and the module unloading will be stopped
inside kprobes_module_callback().
The mutex_lock() has originally been introduced to avoid conflict with text modification,
at that point we didn't hold text_mutex.
But after:
f1c6ece237 ("kprobes: Fix potential deadlock in kprobe_optimizer()")
We started holding the text_mutex and don't need the modules mutex anyway.
So remove the module_mutex locking.
[ mingo: Amended the changelog. ]
Suggested-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Link: https://lore.kernel.org/r/20200728163400.e00b09c594763349f99ce6cb@kernel.org
There are a couple of arguments of the boolean flag zero_size_allowed and
the char pointer buf_info when calling to function check_buffer_access that
are swapped by mistake. Fix these by swapping them to correct the argument
ordering.
Fixes: afbf21dce6 ("bpf: Support readonly/readwrite buffers in verifier")
Addresses-Coverity: ("Array compared to 0")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200727175411.155179-1-colin.king@canonical.com
The method handle_event() grew a lot of complexity due to the design of
fanotify and merging of ignore masks.
Most backends do not care about this complex functionality, so we can hide
this complexity from them.
Introduce a method handle_inode_event() that serves those backends and
passes a single inode mark and less arguments.
This change converts all backends except fanotify and inotify to use the
simplified handle_inode_event() method. In pricipal, inotify could have
also used the new method, but that would require passing more arguments
on the simple helper (data, data_type, cookie), so we leave it with the
handle_event() method.
Link: https://lore.kernel.org/r/20200722125849.17418-9-amir73il@gmail.com
Suggested-by: Jan Kara <jack@suse.cz>
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
The audit group marks mask does not contain any events possible on
a child so setting the flag FS_EVENT_ON_CHILD in the mask is counter
productive.
It may lead to the undesired outcome of setting the dentry flag
DCACHE_FSNOTIFY_PARENT_WATCHED on a directory inode even though it is
not watching children, because the audit mark contribute the flag
FS_EVENT_ON_CHILD to the inode's fsnotify_mask and another mark could
be contributing an event that is possible on child to the inode's mask.
Furthermore in the following patches we want to use FS_EVENT_ON_CHILD
for non-dir inodes for other purposes so stop using the flag.
Link: https://lore.kernel.org/r/20200722125849.17418-4-amir73il@gmail.com
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
->regset_get() takes task+regset+buffer, returns the amount of free space
left in the buffer on success and -E... on error.
buffer is represented as struct membuf - a pair of (kernel) pointer
and amount of space left
Primitives for writing to such:
* membuf_write(buf, data, size)
* membuf_zero(buf, size)
* membuf_store(buf, value)
These are implemented as inlines (in case of membuf_store - a macro).
All writes are sequential; they become no-ops when there's no space
left. Return value of all primitives is the amount of space left
after the operation, so they can be used as return values of ->regset_get().
Example of use:
// stores pt_regs of task + 64 bytes worth of zeroes + 32bit PID of task
int foo_get(struct task_struct *task, const struct regset *regset,
struct membuf to)
{
membuf_write(&to, task_pt_regs(task), sizeof(struct pt_regs));
membuf_zero(&to, 64);
return membuf_store(&to, (u32)task_tgid_vnr(task));
}
regset_get()/regset_get_alloc() taught to use that thing if present.
By the end of the series all users of ->get() will be converted;
then ->get() and ->get_size() can go.
Note that unlike ->get() this thing always starts at offset 0 and,
since it only writes to kernel buffer, can't fail on copyout.
It can, of course, fail for other reasons, but those tend to
be less numerous.
The caller guarantees that the buffer size won't be bigger than
regset->n * regset->size. That simplifies life for quite a few
instances.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Turn copy_regset_to_user() into regset_get_alloc() + copy_to_user().
Now all ->get() calls have a kernel buffer as destination.
Note that we'd already eliminated the callers of copy_regset_to_user()
with non-zero offset; now that argument is simply unused.
Uninlined, while we are at it.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Two new helpers: given a process and regset, dump into a buffer.
regset_get() takes a buffer and size, regset_get_alloc() takes size
and allocates a buffer.
Return value in both cases is the amount of data actually dumped in
case of success or -E... on error.
In both cases the size is capped by regset->n * regset->size, so
->get() is called with offset 0 and size no more than what regset
expects.
binfmt_elf.c callers of ->get() are switched to using those; the other
caller (copy_regset_to_user()) will need some preparations to switch.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
The 'inode' argument to handle_event(), sometimes referred to as
'to_tell' is somewhat obsolete.
It is a remnant from the times when a group could only have an inode mark
associated with an event.
We now pass an iter_info array to the callback, with all marks associated
with an event.
Most backends ignore this argument, with two exceptions:
1. dnotify uses it for sanity check that event is on directory
2. fanotify uses it to report fid of directory on directory entry
modification events
Remove the 'inode' argument and add a 'dir' argument.
The callback function signature is deliberately changed, because
the meaning of the argument has changed and the arguments have
been documented.
The 'dir' argument is set to when 'file_name' is specified and it is
referring to the directory that the 'file_name' entry belongs to.
Signed-off-by: Amir Goldstein <amir73il@gmail.com>
Signed-off-by: Jan Kara <jack@suse.cz>
John reported that on a RK3288 system the perf per CPU interrupts are all
affine to CPU0 and provided the analysis:
"It looks like what happens is that because the interrupts are not per-CPU
in the hardware, armpmu_request_irq() calls irq_force_affinity() while
the interrupt is deactivated and then request_irq() with IRQF_PERCPU |
IRQF_NOBALANCING.
Now when irq_startup() runs with IRQ_STARTUP_NORMAL, it calls
irq_setup_affinity() which returns early because IRQF_PERCPU and
IRQF_NOBALANCING are set, leaving the interrupt on its original CPU."
This was broken by the recent commit which blocked interrupt affinity
setting in hardware before activation of the interrupt. While this works in
general, it does not work for this particular case. As contrary to the
initial analysis not all interrupt chip drivers implement an activate
callback, the safe cure is to make the deferred interrupt affinity setting
at activation time opt-in.
Implement the necessary core logic and make the two irqchip implementations
for which this is required opt-in. In hindsight this would have been the
right thing to do, but ...
Fixes: baedb87d1b ("genirq/affinity: Handle affinity setting on inactive interrupts correctly")
Reported-by: John Keeping <john@metanate.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Marc Zyngier <maz@kernel.org>
Acked-by: Marc Zyngier <maz@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/87blk4tzgm.fsf@nanos.tec.linutronix.de
Prior to commit:
859d069ee1 ("lockdep: Prepare for NMI IRQ state tracking")
IRQ state tracking was disabled in NMIs due to nmi_enter()
doing lockdep_off() -- with the obvious requirement that NMI entry
call nmi_enter() before trace_hardirqs_off().
[ AFAICT, PowerPC and SH violate this order on their NMI entry ]
However, that commit explicitly changed lockdep_hardirqs_*() to ignore
lockdep_off() and breaks every architecture that has irq-tracing in
it's NMI entry that hasn't been fixed up (x86 being the only fixed one
at this point).
The reason for this change is that by ignoring lockdep_off() we can:
- get rid of 'current->lockdep_recursion' in lockdep_assert_irqs*()
which was going to to give header-recursion issues with the
seqlock rework.
- allow these lockdep_assert_*() macros to function in NMI context.
Restore the previous state of things and allow an architecture to
opt-in to the NMI IRQ tracking support, however instead of relying on
lockdep_off(), rely on in_nmi(), both are part of nmi_enter() and so
over-all entry ordering doesn't need to change.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200727124852.GK119549@hirez.programming.kicks-ass.net
Add EXPORT_SYMBOL_GPL entries for irq_chip_retrigger_hierarchy()
and irq_chip_set_vcpu_affinity_parent() so that we can allow
drivers like the qcom-pdc driver to be loadable as a module.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Maulik Shah <mkshah@codeaurora.org>
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: iommu@lists.linux-foundation.org
Cc: linux-gpio@vger.kernel.org
Link: https://lore.kernel.org/r/20200710231824.60699-3-john.stultz@linaro.org
Add export for irq_domain_update_bus_token() so that
we can allow drivers like the qcom-pdc driver to be
loadable as a module.
Signed-off-by: John Stultz <john.stultz@linaro.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Gross <agross@kernel.org>
Cc: Bjorn Andersson <bjorn.andersson@linaro.org>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jason Cooper <jason@lakedaemon.net>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Maulik Shah <mkshah@codeaurora.org>
Cc: Lina Iyer <ilina@codeaurora.org>
Cc: Saravana Kannan <saravanak@google.com>
Cc: Todd Kjos <tkjos@google.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: linux-arm-msm@vger.kernel.org
Cc: iommu@lists.linux-foundation.org
Cc: linux-gpio@vger.kernel.org
Link: https://lore.kernel.org/r/20200710231824.60699-2-john.stultz@linaro.org
The is_fwnode_irqchip() helper will check if the fwnode_handle is empty.
There is no need to perform a redundant check outside of it.
Signed-off-by: Zenghui Yu <yuzenghui@huawei.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20200716083905.287-1-yuzenghui@huawei.com
The noinstr attribute is to be specified before the return type in the
same way 'inline' is used.
Similar cases were recently fixed for x86 in commit 7f6fa101df ("x86:
Correct noinstr qualifiers"), but the generic entry code was based on the
the original version and did not carry the fix over.
Fixes: a5497bab5f ("entry: Provide generic interrupt entry/exit code")
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200725091951.744848-3-mingo@kernel.org
Add bpf_link-based API (bpf_xdp_link) to attach BPF XDP program through
BPF_LINK_CREATE command.
bpf_xdp_link is mutually exclusive with direct BPF program attachment,
previous BPF program should be detached prior to attempting to create a new
bpf_xdp_link attachment (for a given XDP mode). Once BPF link is attached, it
can't be replaced by other BPF program attachment or link attachment. It will
be detached only when the last BPF link FD is closed.
bpf_xdp_link will be auto-detached when net_device is shutdown, similarly to
how other BPF links behave (cgroup, flow_dissector). At that point bpf_link
will become defunct, but won't be destroyed until last FD is closed.
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722064603.3350758-5-andriin@fb.com
Architectures like s390, powerpc, arm64, riscv have speical definition of
bpf_user_pt_regs_t. So we need to cast the pointer before passing it to
bpf_get_stack(). This is similar to bpf_get_stack_tp().
Fixes: 03d42fd2d83f ("bpf: Separate bpf_get_[stack|stackid] for perf events BPF")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200724200503.3629591-1-songliubraving@fb.com
local_storage.o has its compile guard as CONFIG_BPF_SYSCALL, which
does not imply that CONFIG_CGROUP is on. Including cgroup-internal.h
when CONFIG_CGROUP is off cause a compilation failure.
Fixes: f67cfc233706 ("bpf: Make cgroup storages shared between programs on the same cgroup")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200724211753.902969-1-zhuyifei1999@gmail.com
This change comes in several parts:
One, the restriction that the CGROUP_STORAGE map can only be used
by one program is removed. This results in the removal of the field
'aux' in struct bpf_cgroup_storage_map, and removal of relevant
code associated with the field, and removal of now-noop functions
bpf_free_cgroup_storage and bpf_cgroup_storage_release.
Second, we permit a key of type u64 as the key to the map.
Providing such a key type indicates that the map should ignore
attach type when comparing map keys. However, for simplicity newly
linked storage will still have the attach type at link time in
its key struct. cgroup_storage_check_btf is adapted to accept
u64 as the type of the key.
Third, because the storages are now shared, the storages cannot
be unconditionally freed on program detach. There could be two
ways to solve this issue:
* A. Reference count the usage of the storages, and free when the
last program is detached.
* B. Free only when the storage is impossible to be referred to
again, i.e. when either the cgroup_bpf it is attached to, or
the map itself, is freed.
Option A has the side effect that, when the user detach and
reattach a program, whether the program gets a fresh storage
depends on whether there is another program attached using that
storage. This could trigger races if the user is multi-threaded,
and since nondeterminism in data races is evil, go with option B.
The both the map and the cgroup_bpf now tracks their associated
storages, and the storage unlink and free are removed from
cgroup_bpf_detach and added to cgroup_bpf_release and
cgroup_storage_map_free. The latter also new holds the cgroup_mutex
to prevent any races with the former.
Fourth, on attach, we reuse the old storage if the key already
exists in the map, via cgroup_storage_lookup. If the storage
does not exist yet, we create a new one, and publish it at the
last step in the attach process. This does not create a race
condition because for the whole attach the cgroup_mutex is held.
We keep track of an array of new storages that was allocated
and if the process fails only the new storages would get freed.
Signed-off-by: YiFei Zhu <zhuyifei@google.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/d5401c6106728a00890401190db40020a1f84ff1.1595565795.git.zhuyifei@google.com
bpf_get_[stack|stackid] on perf_events with precise_ip uses callchain
attached to perf_sample_data. If this callchain is not presented, do not
allow attaching BPF program that calls bpf_get_[stack|stackid] to this
event.
In the error case, -EPROTO is returned so that libbpf can identify this
error and print proper hint message.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723180648.1429892-3-songliubraving@fb.com
Calling get_perf_callchain() on perf_events from PEBS entries may cause
unwinder errors. To fix this issue, the callchain is fetched early. Such
perf_events are marked with __PERF_SAMPLE_CALLCHAIN_EARLY.
Similarly, calling bpf_get_[stack|stackid] on perf_events from PEBS may
also cause unwinder errors. To fix this, add separate version of these
two helpers, bpf_get_[stack|stackid]_pe. These two hepers use callchain in
bpf_perf_event_data_kern->data->callchain.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723180648.1429892-2-songliubraving@fb.com
The bpf iterators for array and percpu array
are implemented. Similar to hash maps, for percpu
array map, bpf program will receive values
from all cpus.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184115.590532-1-yhs@fb.com
The bpf iterators for hash, percpu hash, lru hash
and lru percpu hash are implemented. During link time,
bpf_iter_reg->check_target() will check map type
and ensure the program access key/value region is
within the map defined key/value size limit.
For percpu hash and lru hash maps, the bpf program
will receive values for all cpus. The map element
bpf iterator infrastructure will prepare value
properly before passing the value pointer to the
bpf program.
This patch set supports readonly map keys and
read/write map values. It does not support deleting
map elements, e.g., from hash tables. If there is
a user case for this, the following mechanism can
be used to support map deletion for hashtab, etc.
- permit a new bpf program return value, e.g., 2,
to let bpf iterator know the map element should
be removed.
- since bucket lock is taken, the map element will be
queued.
- once bucket lock is released after all elements under
this bucket are traversed, all to-be-deleted map
elements can be deleted.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184114.590470-1-yhs@fb.com
The bpf iterator for map elements are implemented.
The bpf program will receive four parameters:
bpf_iter_meta *meta: the meta data
bpf_map *map: the bpf_map whose elements are traversed
void *key: the key of one element
void *value: the value of the same element
Here, meta and map pointers are always valid, and
key has register type PTR_TO_RDONLY_BUF_OR_NULL and
value has register type PTR_TO_RDWR_BUF_OR_NULL.
The kernel will track the access range of key and value
during verification time. Later, these values will be compared
against the values in the actual map to ensure all accesses
are within range.
A new field iter_seq_info is added to bpf_map_ops which
is used to add map type specific information, i.e., seq_ops,
init/fini seq_file func and seq_file private data size.
Subsequent patches will have actual implementation
for bpf_map_ops->iter_seq_info.
In user space, BPF_ITER_LINK_MAP_FD needs to be
specified in prog attr->link_create.flags, which indicates
that attr->link_create.target_fd is a map_fd.
The reason for such an explicit flag is for possible
future cases where one bpf iterator may allow more than
one possible customization, e.g., pid and cgroup id for
task_file.
Current kernel internal implementation only allows
the target to register at most one required bpf_iter_link_info.
To support the above case, optional bpf_iter_link_info's
are needed, the target can be extended to register such link
infos, and user provided link_info needs to match one of
target supported ones.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184112.590360-1-yhs@fb.com
Readonly and readwrite buffer register states
are introduced. Totally four states,
PTR_TO_RDONLY_BUF[_OR_NULL] and PTR_TO_RDWR_BUF[_OR_NULL]
are supported. As suggested by their respective
names, PTR_TO_RDONLY_BUF[_OR_NULL] are for
readonly buffers and PTR_TO_RDWR_BUF[_OR_NULL]
for read/write buffers.
These new register states will be used
by later bpf map element iterator.
New register states share some similarity to
PTR_TO_TP_BUFFER as it will calculate accessed buffer
size during verification time. The accessed buffer
size will be later compared to other metrics during
later attach/link_create time.
Similar to reg_state PTR_TO_BTF_ID_OR_NULL in bpf
iterator programs, PTR_TO_RDONLY_BUF_OR_NULL or
PTR_TO_RDWR_BUF_OR_NULL reg_types can be set at
prog->aux->bpf_ctx_arg_aux, and bpf verifier will
retrieve the values during btf_ctx_access().
Later bpf map element iterator implementation
will show how such information will be assigned
during target registeration time.
The verifier is also enhanced such that PTR_TO_RDONLY_BUF
can be passed to ARG_PTR_TO_MEM[_OR_NULL] helper argument, and
PTR_TO_RDWR_BUF can be passed to ARG_PTR_TO_MEM[_OR_NULL] or
ARG_PTR_TO_UNINIT_MEM.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184111.590274-1-yhs@fb.com
This patch refactored target bpf_iter_init_seq_priv_t callback
function to accept additional information. This will be needed
in later patches for map element targets since a particular
map should be passed to traverse elements for that particular
map. In the future, other information may be passed to target
as well, e.g., pid, cgroup id, etc. to customize the iterator.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184110.590156-1-yhs@fb.com
There is no functionality change for this patch.
Struct bpf_iter_reg is used to register a bpf_iter target,
which includes information for both prog_load, link_create
and seq_file creation.
This patch puts fields related seq_file creation into
a different structure. This will be useful for map
elements iterator where one iterator covers different
map types and different map types may have different
seq_ops, init/fini private_data function and
private_data size.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200723184109.590030-1-yhs@fb.com
It's mostly a copy paste of commit 6086d29def ("bpf: Add bpf_map iterator")
that is use to implement bpf_seq_file opreations to traverse all bpf programs.
v1->v2: Tweak to use build time btf_id
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Currently, the pos pointer in bpf iterator map/task/task_file
seq_ops->start() is always incremented.
This is incorrect. It should be increased only if
*pos is 0 (for SEQ_START_TOKEN) since these start()
function actually returns the first real object.
If *pos is not 0, it merely found the object
based on the state in seq->private, and not really
advancing the *pos. This patch fixed this issue
by only incrementing *pos if it is 0.
Note that the old *pos calculation, although not
correct, does not affect correctness of bpf_iter
as bpf_iter seq_file->read() does not support llseek.
This patch also renamed "mid" in bpf_map iterator
seq_file private data to "map_id" for better clarity.
Fixes: 6086d29def ("bpf: Add bpf_map iterator")
Fixes: eaaacd2391 ("bpf: Add task and task/file iterator targets")
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200722195156.4029817-1-yhs@fb.com
The UDP reuseport conflict was a little bit tricky.
The net-next code, via bpf-next, extracted the reuseport handling
into a helper so that the BPF sk lookup code could invoke it.
At the same time, the logic for reuseport handling of unconnected
sockets changed via commit efc6b6f6c3
which changed the logic to carry on the reuseport result into the
rest of the lookup loop if we do not return immediately.
This requires moving the reuseport_has_conns() logic into the callers.
While we are here, get rid of inline directives as they do not belong
in foo.c files.
The other changes were cases of more straightforward overlapping
modifications.
Signed-off-by: David S. Miller <davem@davemloft.net>
Though the number of lock-acquisitions is tracked as unsigned long, this
is passed as the divisor to div_s64() which interprets it as a s32,
giving nonsense values with more than 2 billion acquisitons. E.g.
acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg
-------------------------------------------------------------------------
2350439395 0.07 353.38 649647067.36 0.-32
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200725185110.11588-1-chris@chris-wilson.co.uk
The uclamp_mutex lock is initialized statically via DEFINE_MUTEX(),
it is unnecessary to initialize it runtime via mutex_init().
Signed-off-by: Qinglang Miao <miaoqinglang@huawei.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Cc: Patrick Bellasi <patrick.bellasi@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Vincent Guittot <vincent.guittot@linaro.org>
Cc: Dietmar Eggemann <dietmar.eggemann@arm.com>
Link: https://lore.kernel.org/r/20200725085629.98292-1-miaoqinglang@huawei.com
dyndbg populates its callsite info into __verbose section, change that
to a more specific and descriptive name, __dyndbg.
Also, per checkpatch:
simplify __attribute(..) to __section(__dyndbg) declaration.
and 1 spelling fix, decriptor
Acked-by: <jbaron@akamai.com>
Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Link: https://lore.kernel.org/r/20200719231058.1586423-6-jim.cromie@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a tracee is uprobed and it hits int3 inserted by debugger, handle_swbp()
does send_sig(SIGTRAP, current, 0) which means si_code == SI_USER. This used
to work when this code was written, but then GDB started to validate si_code
and now it simply can't use breakpoints if the tracee has an active uprobe:
# cat test.c
void unused_func(void)
{
}
int main(void)
{
return 0;
}
# gcc -g test.c -o test
# perf probe -x ./test -a unused_func
# perf record -e probe_test:unused_func gdb ./test -ex run
GNU gdb (GDB) 10.0.50.20200714-git
...
Program received signal SIGTRAP, Trace/breakpoint trap.
0x00007ffff7ddf909 in dl_main () from /lib64/ld-linux-x86-64.so.2
(gdb)
The tracee hits the internal breakpoint inserted by GDB to monitor shared
library events but GDB misinterprets this SIGTRAP and reports a signal.
Change handle_swbp() to use force_sig(SIGTRAP), this matches do_int3_user()
and fixes the problem.
This is the minimal fix for -stable, arch/x86/kernel/uprobes.c is equally
wrong; it should use send_sigtrap(TRAP_TRACE) instead of send_sig(SIGTRAP),
but this doesn't confuse GDB and needs another x86-specific patch.
Reported-by: Aaron Merey <amerey@redhat.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200723154420.GA32043@redhat.com
Entering a guest is similar to exiting to user space. Pending work like
handling signals, rescheduling, task work etc. needs to be handled before
that.
Provide generic infrastructure to avoid duplication of the same handling
code all over the place.
The transfer to guest mode handling is different from the exit to usermode
handling, e.g. vs. rseq and live patching, so a separate function is used.
The initial list of work items handled is:
TIF_SIGPENDING, TIF_NEED_RESCHED, TIF_NOTIFY_RESUME
Architecture specific TIF flags can be added via defines in the
architecture specific include files.
The calling convention is also different from the syscall/interrupt entry
functions as KVM invokes this from the outer vcpu_run() loop with
interrupts and preemption enabled. To prevent missing a pending work item
it invokes a check for pending TIF work from interrupt disabled code right
before transitioning to guest mode. The lockdep, RCU and tracing state
handling is also done directly around the switch to and from guest mode.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200722220519.833296398@linutronix.de
Like the syscall entry/exit code interrupt/exception entry after the real
low level ASM bits should not be different accross architectures.
Provide a generic version based on the x86 code.
irqentry_enter() is called after the low level entry code and
irqentry_exit() must be invoked right before returning to the low level
code which just contains the actual return logic. The code before
irqentry_enter() and irqentry_exit() must not be instrumented. Code after
irqentry_enter() and before irqentry_exit() can be instrumented.
irqentry_enter() invokes irqentry_enter_from_user_mode() if the
interrupt/exception came from user mode. If if entered from kernel mode it
handles the kernel mode variant of establishing state for lockdep, RCU and
tracing depending on the kernel context it interrupted (idle, non-idle).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200722220519.723703209@linutronix.de
Like syscall entry all architectures have similar and pointlessly different
code to handle pending work before returning from a syscall to user space.
1) One-time syscall exit work:
- rseq syscall exit
- audit
- syscall tracing
- tracehook (single stepping)
2) Preparatory work
- Exit to user mode loop (common TIF handling).
- Architecture specific one time work arch_exit_to_user_mode_prepare()
- Address limit and lockdep checks
3) Final transition (lockdep, tracing, context tracking, RCU). Invokes
arch_exit_to_user_mode() to handle e.g. speculation mitigations
Provide a generic version based on the x86 code which has all the RCU and
instrumentation protections right.
Provide a variant for interrupt return to user mode as well which shares
the above #2 and #3 work items.
After syscall_exit_to_user_mode() and irqentry_exit_to_user_mode() the
architecture code just has to return to user space. The code after
returning from these functions must not be instrumented.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200722220519.613977173@linutronix.de
On syscall entry certain work needs to be done:
- Establish state (lockdep, context tracking, tracing)
- Conditional work (ptrace, seccomp, audit...)
This code is needlessly duplicated and different in all
architectures.
Provide a generic version based on the x86 implementation which has all the
RCU and instrumentation bits right.
As interrupt/exception entry from user space needs parts of the same
functionality, provide a function for this as well.
syscall_enter_from_user_mode() and irqentry_enter_from_user_mode() must be
called right after the low level ASM entry. The calling code must be
non-instrumentable. After the functions returns state is correct and the
subsequent functions can be instrumented.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Acked-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/20200722220519.513463269@linutronix.de
Since the default_wake_function() passes its flags onto
try_to_wake_up(), warn if those flags collide with internal values.
Given that the supplied flags are garbage, no repair can be done but at
least alert the user to the damage they are causing.
In the belief that these errors should be picked up during testing, the
warning is only compiled in under CONFIG_SCHED_DEBUG.
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: https://lore.kernel.org/r/20200723201042.18861-1-chris@chris-wilson.co.uk
The nohz tick code recalculates the timer wheel's next expiry on each idle
loop iteration.
On the other hand, the base next expiry is now always cached and updated
upon timer enqueue and execution. Only timer dequeue may leave
base->next_expiry out of date (but then its stale value won't ever go past
the actual next expiry to be recalculated).
Since recalculating the next_expiry isn't a free operation, especially when
the last wheel level is reached to find out that no timer has been enqueued
at all, reuse the next expiry cache when it is known to be reliable, which
it is most of the time.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200723151641.12236-1-frederic@kernel.org
This is a preparation for debugfs restricted mode.
We don't need debugfs to trace, the removed check stop tracefs to work
if debugfs is not initialised. We instead tries to automount within
debugfs and relay on it's handling. The code path is to create a
backward compatibility from when tracefs was part of debugfs, it is now
standalone and does not need debugfs. When debugfs is in restricted
it is compiled in but not active and return EPERM to clients and
tracefs wont work if it assumes it is active it is compiled in
kernel.
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: https://lore.kernel.org/r/20200716071511.26864-2-peter.enderborg@sony.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Only its reorder field is actually used now, so remove the struct and
embed @reorder directly in parallel_data.
No functional change, just a cleanup.
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>
There's no reason to have two interfaces when there's only one caller.
Removing _possible saves text and simplifies future changes.
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>
A padata instance has effective cpumasks that store the user-supplied
masks ANDed with the online mask, but this middleman is unnecessary.
parallel_data keeps the same information around. Removing this saves
text and code churn in future changes.
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>
pd_setup_cpumasks() has only one caller. Move its contents inline to
prepare for the next cleanup.
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>
padata_stop() has two callers and is unnecessary in both cases. When
pcrypt calls it before padata_free(), it's being unloaded so there are
no outstanding padata jobs[0]. When __padata_free() calls it, it's
either along the same path or else pcrypt initialization failed, which
of course means there are also no outstanding jobs.
Removing it simplifies padata and saves text.
[0] https://lore.kernel.org/linux-crypto/20191119225017.mjrak2fwa5vccazl@gondor.apana.org.au/
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>
padata_start() is only used right after pcrypt allocates an instance
with all possible CPUs, when PADATA_INVALID can't happen, so there's no
need for a separate "start" step. It can be done during allocation to
save text, make using padata easier, and avoid unneeded calls in the
future.
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 following commit:
14533a16c4 ("thermal/cpu-cooling, sched/core: Move the arch_set_thermal_pressure() API to generic scheduler code")
moved the definition of arch_set_thermal_pressure() to sched/core.c, but
kept its declaration in linux/arch_topology.h. When building e.g. an x86
kernel with CONFIG_SCHED_THERMAL_PRESSURE=y, cpufreq_cooling.c ends up
getting the declaration of arch_set_thermal_pressure() from
include/linux/arch_topology.h, which is somewhat awkward.
On top of this, sched/core.c unconditionally defines
o The thermal_pressure percpu variable
o arch_set_thermal_pressure()
while arch_scale_thermal_pressure() does nothing unless redefined by the
architecture.
arch_*() functions are meant to be defined by architectures, so revert the
aforementioned commit and re-implement it in a way that keeps
arch_set_thermal_pressure() architecture-definable, and doesn't define the
thermal pressure percpu variable for kernels that don't need
it (CONFIG_SCHED_THERMAL_PRESSURE=n).
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200712165917.9168-2-valentin.schneider@arm.com
The get_option() maybe return 0, it means that the nr_cpus is
not initialized. Then we will use the stale nr_cpus to initialize
the nr_cpu_ids. So fix it.
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200716070457.53255-1-songmuchun@bytedance.com
In slow path, when selecting idlest group, if both groups have type
group_has_spare, only idle_cpus count gets compared.
As a result, if multiple tasks are created in a tight loop,
and go back to sleep immediately
(while waiting for all tasks to be created),
they may be scheduled on the same core, because CPU is back to idle
when the new fork happen.
For example:
sudo perf record -e sched:sched_wakeup_new -- \
sysbench threads --threads=4 run
...
total number of events: 61582
...
sudo perf script
sysbench 129378 [006] 74586.633466: sched:sched_wakeup_new:
sysbench:129380 [120] success=1 CPU:007
sysbench 129378 [006] 74586.634718: sched:sched_wakeup_new:
sysbench:129381 [120] success=1 CPU:007
sysbench 129378 [006] 74586.635957: sched:sched_wakeup_new:
sysbench:129382 [120] success=1 CPU:007
sysbench 129378 [006] 74586.637183: sched:sched_wakeup_new:
sysbench:129383 [120] success=1 CPU:007
This may have negative impact on performance for workloads with frequent
creation of multiple threads.
In this patch we are using group_util to select idlest group if both groups
have equal number of idle_cpus. Comparing the number of idle cpu is
not enough in this case, because the newly forked thread sleeps
immediately and before we select the cpu for the next one.
This is shown in the trace where the same CPU7 is selected for
all wakeup_new events.
That's why, looking at utilization when there is the same number of
CPU is a good way to see where the previous task was placed. Using
nr_running doesn't solve the problem because the newly forked task is not
running and the cpu would not have been idle in this case and an idle
CPU would have been selected instead.
With this patch newly created tasks would be better distributed.
With this patch:
sudo perf record -e sched:sched_wakeup_new -- \
sysbench threads --threads=4 run
...
total number of events: 74401
...
sudo perf script
sysbench 129455 [006] 75232.853257: sched:sched_wakeup_new:
sysbench:129457 [120] success=1 CPU:008
sysbench 129455 [006] 75232.854489: sched:sched_wakeup_new:
sysbench:129458 [120] success=1 CPU:009
sysbench 129455 [006] 75232.855732: sched:sched_wakeup_new:
sysbench:129459 [120] success=1 CPU:010
sysbench 129455 [006] 75232.856980: sched:sched_wakeup_new:
sysbench:129460 [120] success=1 CPU:011
We tested this patch with following benchmarks:
master: 'commit b3a9e3b962 ("Linux 5.8-rc1")'
100 iterations of: perf bench -f simple futex wake -s -t 128 -w 1
Lower result is better
| | BASELINE | +PATCH | DELTA (%) |
|---------|------------|----------|-------------|
| mean | 0.33 | 0.313 | +5.152 |
| std (%) | 10.433 | 7.563 | |
100 iterations of: sysbench threads --threads=8 run
Higher result is better
| | BASELINE | +PATCH | DELTA (%) |
|---------|------------|----------|-------------|
| mean | 5235.02 | 5863.73 | +12.01 |
| std (%) | 8.166 | 10.265 | |
100 iterations of: sysbench mutex --mutex-num=1 --threads=8 run
Lower result is better
| | BASELINE | +PATCH | DELTA (%) |
|---------|------------|----------|-------------|
| mean | 0.413 | 0.404 | +2.179 |
| std (%) | 3.791 | 1.816 | |
Signed-off-by: Peter Puhov <peter.puhov@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200714125941.4174-1-peter.puhov@linaro.org
The "ticks" parameter was added in commit 0f004f5a69 ("sched: Cure more
NO_HZ load average woes") since calc_global_nohz() was called and needed
the "ticks" argument.
But in commit c308b56b53 ("sched: Fix nohz load accounting -- again!")
it became unused as the function calc_global_nohz() dropped using "ticks".
Fixes: c308b56b53 ("sched: Fix nohz load accounting -- again!")
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593628458-32290-1-git-send-email-paul.gortmaker@windriver.com
Dave hit the problem fixed by commit:
b6e13e8582 ("sched/core: Fix ttwu() race")
and failed to understand much of the code involved. Per his request a
few comments to (hopefully) clarify things.
Requested-by: Dave Chinner <david@fromorbit.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200702125211.GQ4800@hirez.programming.kicks-ass.net
There is apparently one site that violates the rule that only current
and ttwu() will modify task->state, namely ptrace_{,un}freeze_traced()
will change task->state for a remote task.
Oleg explains:
"TASK_TRACED/TASK_STOPPED was always protected by siglock. In
particular, ttwu(__TASK_TRACED) must be always called with siglock
held. That is why ptrace_freeze_traced() assumes it can safely do
s/TASK_TRACED/__TASK_TRACED/ under spin_lock(siglock)."
This breaks the ordering scheme introduced by commit:
dbfb089d36 ("sched: Fix loadavg accounting race")
Specifically, the reload not matching no longer implies we don't have
to block.
Simply things by noting that what we need is a LOAD->STORE ordering
and this can be provided by a control dependency.
So replace:
prev_state = prev->state;
raw_spin_lock(&rq->lock);
smp_mb__after_spinlock(); /* SMP-MB */
if (... && prev_state && prev_state == prev->state)
deactivate_task();
with:
prev_state = prev->state;
if (... && prev_state) /* CTRL-DEP */
deactivate_task();
Since that already implies the 'prev->state' load must be complete
before allowing the 'prev->on_rq = 0' store to become visible.
Fixes: dbfb089d36 ("sched: Fix loadavg accounting race")
Reported-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Oleg Nesterov <oleg@redhat.com>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Tested-by: Christian Brauner <christian.brauner@ubuntu.com>
One additional field btf_id is added to struct
bpf_ctx_arg_aux to store the precomputed btf_ids.
The btf_id is computed at build time with
BTF_ID_LIST or BTF_ID_LIST_GLOBAL macro definitions.
All existing bpf iterators are changed to used
pre-compute btf_ids.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720163403.1393551-1-yhs@fb.com
Currently, socket types (struct tcp_sock, udp_sock, etc.)
used by bpf_skc_to_*() helpers are computed when vmlinux_btf
is first built in the kernel.
Commit 5a2798ab32
("bpf: Add BTF_ID_LIST/BTF_ID/BTF_ID_UNUSED macros")
implemented a mechanism to compute btf_ids at kernel build
time which can simplify kernel implementation and reduce
runtime overhead by removing in-kernel btf_id calculation.
This patch did exactly this, removing in-kernel btf_id
computation and utilizing build-time btf_id computation.
If CONFIG_DEBUG_INFO_BTF is not defined, BTF_ID_LIST will
define an array with size of 5, which is not enough for
btf_sock_ids. So define its own static array if
CONFIG_DEBUG_INFO_BTF is not defined.
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200720163358.1393023-1-yhs@fb.com
When CONFIG_NET is set but CONFIG_INET isn't, build fails with:
ld: kernel/bpf/net_namespace.o: in function `netns_bpf_attach_type_unneed':
kernel/bpf/net_namespace.c:32: undefined reference to `bpf_sk_lookup_enabled'
ld: kernel/bpf/net_namespace.o: in function `netns_bpf_attach_type_need':
kernel/bpf/net_namespace.c:43: undefined reference to `bpf_sk_lookup_enabled'
This is because without CONFIG_INET bpf_sk_lookup_enabled symbol is not
available. Wrap references to bpf_sk_lookup_enabled with preprocessor
conditionals.
Fixes: 1559b4aa1d ("inet: Run SK_LOOKUP BPF program on socket lookup")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Link: https://lore.kernel.org/bpf/20200721100716.720477-1-jakub@cloudflare.com
In environments where the preservation of audit events and predictable
usage of system memory are prioritized, admins may use a combination of
--backlog_wait_time and -b options at the risk of degraded performance
resulting from backlog waiting. In some cases, this risk may be
preferred to lost events or unbounded memory usage. Ideally, this risk
can be mitigated by making adjustments when backlog waiting is detected.
However, detection can be difficult using the currently available
metrics. For example, an admin attempting to debug degraded performance
may falsely believe a full backlog indicates backlog waiting. It may
turn out the backlog frequently fills up but drains quickly.
To make it easier to reliably track degraded performance to backlog
waiting, this patch makes the following changes:
Add a new field backlog_wait_time_total to the audit status reply.
Initialize this field to zero. Add to this field the total time spent
by the current task on scheduled timeouts while the backlog limit is
exceeded. Reset field to zero upon request via AUDIT_SET.
Tested on Ubuntu 18.04 using complementary changes to the
audit-userspace and audit-testsuite:
- https://github.com/linux-audit/audit-userspace/pull/134
- https://github.com/linux-audit/audit-testsuite/pull/97
Signed-off-by: Max Englander <max.englander@gmail.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
audit_log_string() was inteded to be an internal audit function and
since there are only two internal uses, remove them. Purge all external
uses of it by restructuring code to use an existing audit_log_format()
or using audit_log_format().
Please see the upstream issue
https://github.com/linux-audit/audit-kernel/issues/84
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
To allow the kernel not to play games with set_fs to call exec
implement kernel_execve. The function kernel_execve takes pointers
into kernel memory and copies the values pointed to onto the new
userspace stack.
The calls with arguments from kernel space of do_execve are replaced
with calls to kernel_execve.
The calls do_execve and do_execveat are made static as there are now
no callers outside of exec.
The comments that mention do_execve are updated to refer to
kernel_execve or execve depending on the circumstances. In addition
to correcting the comments, this makes it easy to grep for do_execve
and verify it is not used.
Inspired-by: https://lkml.kernel.org/r/20200627072704.2447163-1-hch@lst.de
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lkml.kernel.org/r/87wo365ikj.fsf@x220.int.ebiederm.org
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Take the properties of the kexec kernel's inode and the current task
ownership into consideration when matching a KEXEC_CMDLINE operation to
the rules in the IMA policy. This allows for some uniformity when
writing IMA policy rules for KEXEC_KERNEL_CHECK, KEXEC_INITRAMFS_CHECK,
and KEXEC_CMDLINE operations.
Prior to this patch, it was not possible to write a set of rules like
this:
dont_measure func=KEXEC_KERNEL_CHECK obj_type=foo_t
dont_measure func=KEXEC_INITRAMFS_CHECK obj_type=foo_t
dont_measure func=KEXEC_CMDLINE obj_type=foo_t
measure func=KEXEC_KERNEL_CHECK
measure func=KEXEC_INITRAMFS_CHECK
measure func=KEXEC_CMDLINE
The inode information associated with the kernel being loaded by a
kexec_kernel_load(2) syscall can now be included in the decision to
measure or not
Additonally, the uid, euid, and subj_* conditionals can also now be
used in KEXEC_CMDLINE rules. There was no technical reason as to why
those conditionals weren't being considered previously other than
ima_match_rules() didn't have a valid inode to use so it immediately
bailed out for KEXEC_CMDLINE operations rather than going through the
full list of conditional comparisons.
Signed-off-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
Reviewed-by: Lakshmi Ramasubramanian <nramas@linux.microsoft.com>
Signed-off-by: Mimi Zohar <zohar@linux.ibm.com>
sched_clock uses seqcount_t latching to switch between two storage
places protected by the sequence counter. This allows it to have
interruptible, NMI-safe, seqcount_t write side critical sections.
Since 7fc26327b7 ("seqlock: Introduce raw_read_seqcount_latch()"),
raw_read_seqcount_latch() became the standardized way for seqcount_t
latch read paths. Due to the dependent load, it also has one read
memory barrier less than the currently used raw_read_seqcount() API.
Use raw_read_seqcount_latch() for the seqcount_t latch read path.
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Link: https://lkml.kernel.org/r/20200625085745.GD117543@hirez.programming.kicks-ass.net
Link: https://lkml.kernel.org/r/20200715092345.GA231464@debian-buster-darwi.lab.linutronix.de
Link: https://lore.kernel.org/r/20200716051130.4359-3-leo.yan@linaro.org
References: 1809bfa44e ("timers, sched/clock: Avoid deadlock during read from NMI")
Signed-off-by: Will Deacon <will@kernel.org>
In order to support perf_event_mmap_page::cap_time features, an
architecture needs, aside from a userspace readable counter register,
to expose the exact clock data so that userspace can convert the
counter register into a correct timestamp.
Provide struct clock_read_data and two (seqcount) helpers so that
architectures (arm64 in specific) can expose the numbers to userspace.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Link: https://lore.kernel.org/r/20200716051130.4359-2-leo.yan@linaro.org
Signed-off-by: Will Deacon <will@kernel.org>
- A timer which is already expired at enqueue time can set the
base->next_expiry value backwards. As a consequence base->clk can be set
back as well. This can lead to timers expiring early. Add a sanity check
to prevent this.
- When a timer is queued with an expiry time beyond the wheel capacity
then it should be queued in the bucket of the last wheel level which is
expiring last. The code adjusts expiry time to the maximum wheel
capacity, which is only correct when the wheel clock is 0. Aside of that
the check whether the delta is larger than wheel capacity does not check
the delta, it checks the expiry value itself. As a result timers can
expire at random.
Fix this by checking the right variable and adjust expiry time so it
becomes base->clock plus capacity which places it into the outmost
bucket in the last wheel level.
-----BEGIN PGP SIGNATURE-----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=aCiv
-----END PGP SIGNATURE-----
Merge tag 'timers-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull timer fixes from Thomas Gleixner:
"Two fixes for the timer wheel:
- A timer which is already expired at enqueue time can set the
base->next_expiry value backwards. As a consequence base->clk can
be set back as well. This can lead to timers expiring early. Add a
sanity check to prevent this.
- When a timer is queued with an expiry time beyond the wheel
capacity then it should be queued in the bucket of the last wheel
level which is expiring last.
The code adjusted the expiry time to the maximum wheel capacity,
which is only correct when the wheel clock is 0. Aside of that the
check whether the delta is larger than wheel capacity does not
check the delta, it checks the expiry value itself. As a result
timers can expire at random.
Fix this by checking the right variable and adjust expiry time so
it becomes base->clock plus capacity which places it into the
outmost bucket in the last wheel level"
* tag 'timers-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timer: Fix wheel index calculation on last level
timer: Prevent base->clk from moving backward
- Plug a load average accounting race which was introduced with a recent
optimization casing load average to show bogus numbers.
- Fix the rseq CPU id initialization for new tasks. sched_fork() does not
update the rseq CPU id so the id is the stale id of the parent task,
which can cause user space data corruption.
- Handle a 0 return value of task_h_load() correctly in the load balancer,
which does not decrease imbalance and therefore pulls until the maximum
number of loops is reached, which might be all tasks just created by a
fork bomb.
-----BEGIN PGP SIGNATURE-----
iQJHBAABCgAxFiEEQp8+kY+LLUocC4bMphj1TA10mKEFAl8UQrITHHRnbHhAbGlu
dXRyb25peC5kZQAKCRCmGPVMDXSYoTNgD/4+uP0wmIuYAJd1WmpifX+G9h+3NIiU
zfLTxGeo+D/I+rdeS7ClyjeSTcZHl1fQfZBIopMevsEMymMu2BbQd+OeAlkESbS6
dp6G3dv0ZGbm9Sn4G3CEEPltoCJi7pOgRrixGi/o4APkNfy3U2r+w/kM1N6AwHE0
PYztzvq5Q++m+MEHOALsB1J8mc7vygU26EO4s/rRrV6/RnNZXL269PeZRFxxEvYn
rtmyUw53Lc72Y+23FuityE/jb2xkr80yuXQWxTOxbhzBtHO1omWQQVhBTMam5RDg
NUYzeZvK/nZW3i6WOuHyaaLj7+2ML7RmNpaYRueymJinda409GDXRcDOYXNFtxcI
lcVmsxzNF5rb7b9mXqdgdSJKuZotKLnTjXAIGhHzkSkl2uYfYW6PUGxq6BmSCKvR
GpewHQ8Ynf4JcsjioOTQjRNjJYmlrTsHcUUKXsyTIfYaEEw+i/7s/7G5G7bXxJ6G
Sma52oTyrsFQEG+AjT2CxhOzxQumtT5vQ9/l8EvnQXQdG7fZzIimgWnTBc6IE83J
OPYI8WomKhj+EkJSltxUQm+ZwqhDv4rBHQ+SqPr+jhvPobUN6jS0HkOoW+SIGuo4
oMRvMiNhCyUWLFYMVL2pflJANyiFczfKWyAqyjwgiSjfNaTqSmYCcPOc1NWz/Ic4
fGMLMqFQ2fW/rg==
=bCPw
-----END PGP SIGNATURE-----
Merge tag 'sched-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull scheduler fixes from Thomas Gleixner:
"A set of scheduler fixes:
- Plug a load average accounting race which was introduced with a
recent optimization casing load average to show bogus numbers.
- Fix the rseq CPU id initialization for new tasks. sched_fork() does
not update the rseq CPU id so the id is the stale id of the parent
task, which can cause user space data corruption.
- Handle a 0 return value of task_h_load() correctly in the load
balancer, which does not decrease imbalance and therefore pulls
until the maximum number of loops is reached, which might be all
tasks just created by a fork bomb"
* tag 'sched-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: handle case of task_h_load() returning 0
sched: Fix unreliable rseq cpu_id for new tasks
sched: Fix loadavg accounting race
- Make the handling of the firmware node consistent and do not free the
node after the domain has been created successfully. The core code
stores a pointer to it which can lead to a use after free or double
free.
This used to "work" because the pointer was not stored when the initial
code was written, but at some point later it was required to store
it. Of course nobody noticed that the existing users break that way.
- Handle affinity setting on inactive interrupts correctly when
hierarchical irq domains are enabled. When interrupts are inactive with
the modern hierarchical irqdomain design, the interrupt chips are not
necessarily in a state where affinity changes can be handled. The legacy
irq chip design allowed this because interrupts are immediately fully
initialized at allocation time. X86 has a hacky workaround for this, but
other implementations do not. This cased malfunction on GIC-V3. Instead
of playing whack a mole to find all affected drivers, change the core
code to store the requested affinity setting and then establish it when
the interrupt is allocated, which makes the X86 hack go away.
-----BEGIN PGP SIGNATURE-----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=elM3
-----END PGP SIGNATURE-----
Merge tag 'irq-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip into master
Pull irq fixes from Thomas Gleixner:
"Two fixes for the interrupt subsystem:
- Make the handling of the firmware node consistent and do not free
the node after the domain has been created successfully. The core
code stores a pointer to it which can lead to a use after free or
double free.
This used to "work" because the pointer was not stored when the
initial code was written, but at some point later it was required
to store it. Of course nobody noticed that the existing users break
that way.
- Handle affinity setting on inactive interrupts correctly when
hierarchical irq domains are enabled.
When interrupts are inactive with the modern hierarchical irqdomain
design, the interrupt chips are not necessarily in a state where
affinity changes can be handled. The legacy irq chip design allowed
this because interrupts are immediately fully initialized at
allocation time. X86 has a hacky workaround for this, but other
implementations do not.
This cased malfunction on GIC-V3. Instead of playing whack a mole
to find all affected drivers, change the core code to store the
requested affinity setting and then establish it when the interrupt
is allocated, which makes the X86 hack go away"
* tag 'irq-urgent-2020-07-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
genirq/affinity: Handle affinity setting on inactive interrupts correctly
irqdomain/treewide: Keep firmware node unconditionally allocated
This brings consistency with the rest of the prctl() syscall where
-EPERM is returned when failing a capability check.
Signed-off-by: Nicolas Viennot <Nicolas.Viennot@twosigma.com>
Signed-off-by: Adrian Reber <areber@redhat.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Link: https://lore.kernel.org/r/20200719100418.2112740-7-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Originally, only a local CAP_SYS_ADMIN could change the exe link,
making it difficult for doing checkpoint/restore without CAP_SYS_ADMIN.
This commit adds CAP_CHECKPOINT_RESTORE in addition to CAP_SYS_ADMIN
for permitting changing the exe link.
The following describes the history of the /proc/self/exe permission
checks as it may be difficult to understand what decisions lead to this
point.
* [1] May 2012: This commit introduces the ability of changing
/proc/self/exe if the user is CAP_SYS_RESOURCE capable.
In the related discussion [2], no clear thread model is presented for
what could happen if the /proc/self/exe changes multiple times, or why
would the admin be at the mercy of userspace.
* [3] Oct 2014: This commit introduces a new API to change
/proc/self/exe. The permission no longer checks for CAP_SYS_RESOURCE,
but instead checks if the current user is root (uid=0) in its local
namespace. In the related discussion [4] it is said that "Controlling
exe_fd without privileges may turn out to be dangerous. At least
things like tomoyo examine it for making policy decisions (see
tomoyo_manager())."
* [5] Dec 2016: This commit removes the restriction to change
/proc/self/exe at most once. The related discussion [6] informs that
the audit subsystem relies on the exe symlink, presumably
audit_log_d_path_exe() in kernel/audit.c.
* [7] May 2017: This commit changed the check from uid==0 to local
CAP_SYS_ADMIN. No discussion.
* [8] July 2020: A PoC to spoof any program's /proc/self/exe via ptrace
is demonstrated
Overall, the concrete points that were made to retain capability checks
around changing the exe symlink is that tomoyo_manager() and
audit_log_d_path_exe() uses the exe_file path.
Christian Brauner said that relying on /proc/<pid>/exe being immutable (or
guarded by caps) in a sake of security is a bit misleading. It can only
be used as a hint without any guarantees of what code is being executed
once execve() returns to userspace. Christian suggested that in the
future, we could call audit_log() or similar to inform the admin of all
exe link changes, instead of attempting to provide security guarantees
via permission checks. However, this proposed change requires the
understanding of the security implications in the tomoyo/audit subsystems.
[1] b32dfe3771 ("c/r: prctl: add ability to set new mm_struct::exe_file")
[2] https://lore.kernel.org/patchwork/patch/292515/
[3] f606b77f1a ("prctl: PR_SET_MM -- introduce PR_SET_MM_MAP operation")
[4] https://lore.kernel.org/patchwork/patch/479359/
[5] 3fb4afd9a5 ("prctl: remove one-shot limitation for changing exe link")
[6] https://lore.kernel.org/patchwork/patch/697304/
[7] 4d28df6152 ("prctl: Allow local CAP_SYS_ADMIN changing exe_file")
[8] https://github.com/nviennot/run_as_exe
Signed-off-by: Nicolas Viennot <Nicolas.Viennot@twosigma.com>
Signed-off-by: Adrian Reber <areber@redhat.com>
Link: https://lore.kernel.org/r/20200719100418.2112740-6-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Use the newly introduced capability CAP_CHECKPOINT_RESTORE to allow
writing to ns_last_pid.
Signed-off-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Nicolas Viennot <Nicolas.Viennot@twosigma.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200719100418.2112740-4-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Use the newly introduced capability CAP_CHECKPOINT_RESTORE to allow
using clone3() with set_tid set.
Signed-off-by: Adrian Reber <areber@redhat.com>
Signed-off-by: Nicolas Viennot <Nicolas.Viennot@twosigma.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200719100418.2112740-3-areber@redhat.com
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Make dir2name a little more readable and maintainable by using
named initializers.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Robin Murphy <robin.murphy@arm.com>
Several IOMMU drivers have a bypass mode where they can use a direct
mapping if the devices DMA mask is large enough. Add generic support
to the core dma-mapping code to do that to switch those drivers to
a common solution.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Avoid the overhead of the dma ops support for tiny builds that only
use the direct mapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Run a BPF program before looking up a listening socket on the receive path.
Program selects a listening socket to yield as result of socket lookup by
calling bpf_sk_assign() helper and returning SK_PASS code. Program can
revert its decision by assigning a NULL socket with bpf_sk_assign().
Alternatively, BPF program can also fail the lookup by returning with
SK_DROP, or let the lookup continue as usual with SK_PASS on return, when
no socket has been selected with bpf_sk_assign().
This lets the user match packets with listening sockets freely at the last
possible point on the receive path, where we know that packets are destined
for local delivery after undergoing policing, filtering, and routing.
With BPF code selecting the socket, directing packets destined to an IP
range or to a port range to a single socket becomes possible.
In case multiple programs are attached, they are run in series in the order
in which they were attached. The end result is determined from return codes
of all the programs according to following rules:
1. If any program returned SK_PASS and selected a valid socket, the socket
is used as result of socket lookup.
2. If more than one program returned SK_PASS and selected a socket,
last selection takes effect.
3. If any program returned SK_DROP, and no program returned SK_PASS and
selected a socket, socket lookup fails with -ECONNREFUSED.
4. If all programs returned SK_PASS and none of them selected a socket,
socket lookup continues to htable-based lookup.
Suggested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200717103536.397595-5-jakub@cloudflare.com
Add a new program type BPF_PROG_TYPE_SK_LOOKUP with a dedicated attach type
BPF_SK_LOOKUP. The new program kind is to be invoked by the transport layer
when looking up a listening socket for a new connection request for
connection oriented protocols, or when looking up an unconnected socket for
a packet for connection-less protocols.
When called, SK_LOOKUP BPF program can select a socket that will receive
the packet. This serves as a mechanism to overcome the limits of what
bind() API allows to express. Two use-cases driving this work are:
(1) steer packets destined to an IP range, on fixed port to a socket
192.0.2.0/24, port 80 -> NGINX socket
(2) steer packets destined to an IP address, on any port to a socket
198.51.100.1, any port -> L7 proxy socket
In its run-time context program receives information about the packet that
triggered the socket lookup. Namely IP version, L4 protocol identifier, and
address 4-tuple. Context can be further extended to include ingress
interface identifier.
To select a socket BPF program fetches it from a map holding socket
references, like SOCKMAP or SOCKHASH, and calls bpf_sk_assign(ctx, sk, ...)
helper to record the selection. Transport layer then uses the selected
socket as a result of socket lookup.
In its basic form, SK_LOOKUP acts as a filter and hence must return either
SK_PASS or SK_DROP. If the program returns with SK_PASS, transport should
look for a socket to receive the packet, or use the one selected by the
program if available, while SK_DROP informs the transport layer that the
lookup should fail.
This patch only enables the user to attach an SK_LOOKUP program to a
network namespace. Subsequent patches hook it up to run on local delivery
path in ipv4 and ipv6 stacks.
Suggested-by: Marek Majkowski <marek@cloudflare.com>
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200717103536.397595-3-jakub@cloudflare.com
Extend the BPF netns link callbacks to rebuild (grow/shrink) or update the
prog_array at given position when link gets attached/updated/released.
This let's us lift the limit of having just one link attached for the new
attach type introduced by subsequent patch.
No functional changes intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200717103536.397595-2-jakub@cloudflare.com
Since 82af7aca ("Removal of FUTEX_FD"), some includes related to file
operations aren't needed anymore. More investigation around the includes
showed that a lot of includes aren't required for compilation, possible
due to redundant includes. Simplify the code by removing unused
includes.
Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200702202843.520764-4-andrealmeid@collabora.com
Since fshared is only conveying true/false values, declare it as bool.
In get_futex_key() the usage of fshared can be restricted to the first part
of the function. If fshared is false the function is terminated early and
the subsequent code can use a constant 'true' instead of the variable.
Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200702202843.520764-5-andrealmeid@collabora.com
As stated in the coding style documentation, "if there is no cleanup
needed then just return directly", instead of jumping to a label and
then returning.
Remove such goto's and replace with a return statement. When there's a
ternary operator on the return value, replace it with the result of the
operation when it is logically possible to determine it by the control
flow.
Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200702202843.520764-3-andrealmeid@collabora.com
Since 4b39f99c ("futex: Remove {get,drop}_futex_key_refs()"),
put_futex_key() is empty.
Remove all references for this function and the then redundant labels.
Signed-off-by: André Almeida <andrealmeid@collabora.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200702202843.520764-2-andrealmeid@collabora.com
Setting interrupt affinity on inactive interrupts is inconsistent when
hierarchical irq domains are enabled. The core code should just store the
affinity and not call into the irq chip driver for inactive interrupts
because the chip drivers may not be in a state to handle such requests.
X86 has a hacky workaround for that but all other irq chips have not which
causes problems e.g. on GIC V3 ITS.
Instead of adding more ugly hacks all over the place, solve the problem in
the core code. If the affinity is set on an inactive interrupt then:
- Store it in the irq descriptors affinity mask
- Update the effective affinity to reflect that so user space has
a consistent view
- Don't call into the irq chip driver
This is the core equivalent of the X86 workaround and works correctly
because the affinity setting is established in the irq chip when the
interrupt is activated later on.
Note, that this is only effective when hierarchical irq domains are enabled
by the architecture. Doing it unconditionally would break legacy irq chip
implementations.
For hierarchial irq domains this works correctly as none of the drivers can
have a dependency on affinity setting in inactive state by design.
Remove the X86 workaround as it is not longer required.
Fixes: 02edee152d ("x86/apic/vector: Ignore set_affinity call for inactive interrupts")
Reported-by: Ali Saidi <alisaidi@amazon.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Ali Saidi <alisaidi@amazon.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20200529015501.15771-1-alisaidi@amazon.com
Link: https://lkml.kernel.org/r/877dv2rv25.fsf@nanos.tec.linutronix.de
There is nothing that prevents from forwarding the base clock if it's one
jiffy off. The reason for this arbitrary limit of two jiffies is historical
and does not longer exist.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-13-frederic@kernel.org
There is no reason to keep this guard around. The code makes sure that
base->clk remains sane and won't be forwarded beyond jiffies nor set
backward.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-12-frederic@kernel.org
Now that the core timer infrastructure doesn't depend anymore on
periodic base->clk increments, even when the CPU is not in NO_HZ mode,
timer softirqs can be skipped until there are timers to expire.
Some spurious softirqs can still remain since base->next_expiry doesn't
keep track of canceled timers but this still reduces the number of softirqs
significantly: ~15 times less for HZ=1000 and ~5 times less for HZ=100.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-11-frederic@kernel.org
As for next_expiry, the base->clk catch up logic will be expanded beyond
NOHZ in order to avoid triggering useless softirqs.
If softirqs should only fire to expire pending timers, periodic base->clk
increments must be skippable for random amounts of time. Therefore prepare
to catch-up with missing updates whenever an up-to-date base clock is
needed.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-10-frederic@kernel.org
Now that the next expiry it tracked unconditionally when a timer is added,
this information can be reused on a tick firing after exiting nohz.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-9-frederic@kernel.org
So far next expiry was only tracked while the CPU was in nohz_idle mode
in order to cope with missing ticks that can't increment the base->clk
periodically anymore.
This logic is going to be expanded beyond nohz in order to spare timer
softirqs so do it unconditionally.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-8-frederic@kernel.org
If a level has a timer that expires before reaching the next level, there
is no need to iterate further.
The next level is reached when the 3 lower bits of the current level are
cleared. If the next event happens before/during that, the next levels
won't provide an earlier expiration.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-7-frederic@kernel.org
calc_index() adds 1 unit of the level granularity to the expiry passed
in parameter to ensure that the timer doesn't expire too early. Add a
comment to explain that and the resulting layout in the wheel.
Suggested-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-6-frederic@kernel.org
Consolidate the code by calling trigger_dyntick_cpu() from
enqueue_timer() instead of calling it from all its callers.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Link: https://lkml.kernel.org/r/20200717140551.29076-5-frederic@kernel.org
The bucket expiry time is the effective expriy time of timers and is
greater than or equal to the requested timer expiry time. This is due
to the guarantee that timers never expire early and the reduced expiry
granularity in the secondary wheel levels.
When a timer is enqueued, trigger_dyntick_cpu() checks whether the
timer is the new first timer. This check compares next_expiry with
the requested timer expiry value and not with the effective expiry
value of the bucket into which the timer was queued.
Storing the requested timer expiry value in base->next_expiry can lead
to base->clk going backwards if the requested timer expiry value is
smaller than base->clk. Commit 30c66fc30e ("timer: Prevent base->clk
from moving backward") worked around this by preventing the store when
timer->expiry is before base->clk, but did not fix the underlying
problem.
Use the expiry value of the bucket into which the timer is queued to
do the new first timer check. This fixes the base->clk going backward
problem.
The workaround of commit 30c66fc30e ("timer: Prevent base->clk from
moving backward") in trigger_dyntick_cpu() is not longer necessary as the
timers bucket expiry is guaranteed to be greater than or equal base->clk.
Signed-off-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200717140551.29076-4-frederic@kernel.org
The higher bits of the timer expiration are cropped while calling
calc_index() due to the implicit cast from unsigned long to unsigned int.
This loss shouldn't have consequences on the current code since all the
computation to calculate the index is done on the lower 32 bits.
However to prepare for returning the actual bucket expiration from
calc_index() in order to properly fix base->next_expiry updates, the higher
bits need to be preserved.
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200717140551.29076-3-frederic@kernel.org
When an expiration delta falls into the last level of the wheel, that delta
has be compared against the maximum possible delay and reduced to fit in if
necessary.
However instead of comparing the delta against the maximum, the code
compares the actual expiry against the maximum. Then instead of fixing the
delta to fit in, it sets the maximum delta as the expiry value.
This can result in various undesired outcomes, the worst possible one
being a timer expiring 15 days ahead to fire immediately.
Fixes: 500462a9de ("timers: Switch to a non-cascading wheel")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200717140551.29076-2-frederic@kernel.org
task_h_load() can return 0 in some situations like running stress-ng
mmapfork, which forks thousands of threads, in a sched group on a 224 cores
system. The load balance doesn't handle this correctly because
env->imbalance never decreases and it will stop pulling tasks only after
reaching loop_max, which can be equal to the number of running tasks of
the cfs. Make sure that imbalance will be decreased by at least 1.
misfit task is the other feature that doesn't handle correctly such
situation although it's probably more difficult to face the problem
because of the smaller number of CPUs and running tasks on heterogenous
system.
We can't simply ensure that task_h_load() returns at least one because it
would imply to handle underflow in other places.
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>
Reviewed-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Tested-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Cc: <stable@vger.kernel.org> # v4.4+
Link: https://lkml.kernel.org/r/20200710152426.16981-1-vincent.guittot@linaro.org
Using uninitialized_var() is dangerous as it papers over real bugs[1]
(or can in the future), and suppresses unrelated compiler warnings
(e.g. "unused variable"). If the compiler thinks it is uninitialized,
either simply initialize the variable or make compiler changes.
In preparation for removing[2] the[3] macro[4], remove all remaining
needless uses with the following script:
git grep '\buninitialized_var\b' | cut -d: -f1 | sort -u | \
xargs perl -pi -e \
's/\buninitialized_var\(([^\)]+)\)/\1/g;
s:\s*/\* (GCC be quiet|to make compiler happy) \*/$::g;'
drivers/video/fbdev/riva/riva_hw.c was manually tweaked to avoid
pathological white-space.
No outstanding warnings were found building allmodconfig with GCC 9.3.0
for x86_64, i386, arm64, arm, powerpc, powerpc64le, s390x, mips, sparc64,
alpha, and m68k.
[1] https://lore.kernel.org/lkml/20200603174714.192027-1-glider@google.com/
[2] https://lore.kernel.org/lkml/CA+55aFw+Vbj0i=1TGqCR5vQkCzWJ0QxK6CernOU6eedsudAixw@mail.gmail.com/
[3] https://lore.kernel.org/lkml/CA+55aFwgbgqhbp1fkxvRKEpzyR5J8n1vKT1VZdz9knmPuXhOeg@mail.gmail.com/
[4] https://lore.kernel.org/lkml/CA+55aFz2500WfbKXAx8s67wrm9=yVJu65TpLgN_ybYNv0VEOKA@mail.gmail.com/
Reviewed-by: Leon Romanovsky <leonro@mellanox.com> # drivers/infiniband and mlx4/mlx5
Acked-by: Jason Gunthorpe <jgg@mellanox.com> # IB
Acked-by: Kalle Valo <kvalo@codeaurora.org> # wireless drivers
Reviewed-by: Chao Yu <yuchao0@huawei.com> # erofs
Signed-off-by: Kees Cook <keescook@chromium.org>
Introduce XDP_REDIRECT support for eBPF programs attached to cpumap
entries.
This patch has been tested on Marvell ESPRESSObin using a modified
version of xdp_redirect_cpu sample in order to attach a XDP program
to CPUMAP entries to perform a redirect on the mvneta interface.
In particular the following scenario has been tested:
rq (cpu0) --> mvneta - XDP_REDIRECT (cpu0) --> CPUMAP - XDP_REDIRECT (cpu1) --> mvneta
$./xdp_redirect_cpu -p xdp_cpu_map0 -d eth0 -c 1 -e xdp_redirect \
-f xdp_redirect_kern.o -m tx_port -r eth0
tx: 285.2 Kpps rx: 285.2 Kpps
Attaching a simple XDP program on eth0 to perform XDP_TX gives
comparable results:
tx: 288.4 Kpps rx: 288.4 Kpps
Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/2cf8373a731867af302b00c4ff16c122630c4980.1594734381.git.lorenzo@kernel.org
Introduce the capability to attach an eBPF program to cpumap entries.
The idea behind this feature is to add the possibility to define on
which CPU run the eBPF program if the underlying hw does not support
RSS. Current supported verdicts are XDP_DROP and XDP_PASS.
This patch has been tested on Marvell ESPRESSObin using xdp_redirect_cpu
sample available in the kernel tree to identify possible performance
regressions. Results show there are no observable differences in
packet-per-second:
$./xdp_redirect_cpu --progname xdp_cpu_map0 --dev eth0 --cpu 1
rx: 354.8 Kpps
rx: 356.0 Kpps
rx: 356.8 Kpps
rx: 356.3 Kpps
rx: 356.6 Kpps
rx: 356.6 Kpps
rx: 356.7 Kpps
rx: 355.8 Kpps
rx: 356.8 Kpps
rx: 356.8 Kpps
Co-developed-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/5c9febdf903d810b3415732e5cd98491d7d9067a.1594734381.git.lorenzo@kernel.org
As it has been already done for devmap, introduce 'struct bpf_cpumap_val'
to formalize the expected values that can be passed in for a CPUMAP.
Update cpumap code to use the struct.
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Jesper Dangaard Brouer <brouer@redhat.com>
Link: https://lore.kernel.org/bpf/754f950674665dae6139c061d28c1d982aaf4170.1594734381.git.lorenzo@kernel.org
Commit 77361825bb ("bpf: cpumap use ptr_ring_consume_batched") changed
away from using single frame ptr_ring dequeue (__ptr_ring_consume) to
consume a batched, but it uses a locked version, which as the comment
explain isn't needed.
Change to use the non-locked version __ptr_ring_consume_batched.
Fixes: 77361825bb ("bpf: cpumap use ptr_ring_consume_batched")
Signed-off-by: Jesper Dangaard Brouer <brouer@redhat.com>
Signed-off-by: Lorenzo Bianconi <lorenzo@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/a9c7d06f9a009e282209f0c8c7b2c5d9b9ad60b9.1594734381.git.lorenzo@kernel.org
Inline the single page map/unmap/sync dma-direct calls into the now
out of line generic wrappers. This restores the behavior of a single
function call that we had before moving the generic calls out of line.
Besides the dma-mapping callers there are just a few callers in IOMMU
drivers that have a bypass mode, and more of those are going to be
switched to the generic bypass soon.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
For a long time the DMA API has been implemented inline in dma-mapping.h,
but the function bodies can be quite large. Move them all out of line.
This also removes all the dma_direct_* exports as those are just
implementation details and should never be used by drivers directly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Tested-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Reviewed-by: Alexey Kardashevskiy <aik@ozlabs.ru>
The current SECCOMP_RET_USER_NOTIF API allows for syscall supervision over
an fd. It is often used in settings where a supervising task emulates
syscalls on behalf of a supervised task in userspace, either to further
restrict the supervisee's syscall abilities or to circumvent kernel
enforced restrictions the supervisor deems safe to lift (e.g. actually
performing a mount(2) for an unprivileged container).
While SECCOMP_RET_USER_NOTIF allows for the interception of any syscall,
only a certain subset of syscalls could be correctly emulated. Over the
last few development cycles, the set of syscalls which can't be emulated
has been reduced due to the addition of pidfd_getfd(2). With this we are
now able to, for example, intercept syscalls that require the supervisor
to operate on file descriptors of the supervisee such as connect(2).
However, syscalls that cause new file descriptors to be installed can not
currently be correctly emulated since there is no way for the supervisor
to inject file descriptors into the supervisee. This patch adds a
new addfd ioctl to remove this restriction by allowing the supervisor to
install file descriptors into the intercepted task. By implementing this
feature via seccomp the supervisor effectively instructs the supervisee
to install a set of file descriptors into its own file descriptor table
during the intercepted syscall. This way it is possible to intercept
syscalls such as open() or accept(), and install (or replace, like
dup2(2)) the supervisor's resulting fd into the supervisee. One
replacement use-case would be to redirect the stdout and stderr of a
supervisee into log file descriptors opened by the supervisor.
The ioctl handling is based on the discussions[1] of how Extensible
Arguments should interact with ioctls. Instead of building size into
the addfd structure, make it a function of the ioctl command (which
is how sizes are normally passed to ioctls). To support forward and
backward compatibility, just mask out the direction and size, and match
everything. The size (and any future direction) checks are done along
with copy_struct_from_user() logic.
As a note, the seccomp_notif_addfd structure is laid out based on 8-byte
alignment without requiring packing as there have been packing issues
with uapi highlighted before[2][3]. Although we could overload the
newfd field and use -1 to indicate that it is not to be used, doing
so requires changing the size of the fd field, and introduces struct
packing complexity.
[1]: https://lore.kernel.org/lkml/87o8w9bcaf.fsf@mid.deneb.enyo.de/
[2]: https://lore.kernel.org/lkml/a328b91d-fd8f-4f27-b3c2-91a9c45f18c0@rasmusvillemoes.dk/
[3]: https://lore.kernel.org/lkml/20200612104629.GA15814@ircssh-2.c.rugged-nimbus-611.internal
Cc: Christoph Hellwig <hch@lst.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Jann Horn <jannh@google.com>
Cc: Robert Sesek <rsesek@google.com>
Cc: Chris Palmer <palmer@google.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: linux-fsdevel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: linux-api@vger.kernel.org
Suggested-by: Matt Denton <mpdenton@google.com>
Link: https://lore.kernel.org/r/20200603011044.7972-4-sargun@sargun.me
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Reviewed-by: Will Drewry <wad@chromium.org>
Co-developed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
Fixed string literals can be referred to as "const char *".
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
[ rjw: Minor subject edit ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
In hibernate.c, some places lack of spaces while some places have
redundant spaces. So fix them.
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
There is no guarantee to CMA's placement, so allocating a zone specific
atomic pool from CMA might return memory from a completely different
memory zone. So stop using it.
Fixes: c84dc6e68a ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Tested-by: Jeremy Linton <jeremy.linton@arm.com>
Acked-by: David Rientjes <rientjes@google.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
When allocating DMA memory from a pool, the core can only guess which
atomic pool will fit a device's constraints. If it doesn't, get a safer
atomic pool and try again.
Fixes: c84dc6e68a ("dma-pool: add additional coherent pools to map to gfp mask")
Reported-by: Jeremy Linton <jeremy.linton@arm.com>
Suggested-by: Robin Murphy <robin.murphy@arm.com>
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma-pool's dev_to_pool() creates the false impression that there is a
way to grantee a mapping between a device's DMA constraints and an
atomic pool. It tuns out it's just a guess, and the device might need to
use an atomic pool containing memory from a 'safer' (or lower) memory
zone.
To help mitigate this, introduce dma_guess_pool() which can be fed a
device's DMA constraints and atomic pools already known to be faulty, in
order for it to provide an better guess on which pool to use.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
The function is only used once and can be simplified to a one-liner.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
dma_coherent_ok() checks if a physical memory area fits a device's DMA
constraints.
Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Alexei Starovoitov says:
====================
pull-request: bpf-next 2020-07-13
The following pull-request contains BPF updates for your *net-next* tree.
We've added 36 non-merge commits during the last 7 day(s) which contain
a total of 62 files changed, 2242 insertions(+), 468 deletions(-).
The main changes are:
1) Avoid trace_printk warning banner by switching bpf_trace_printk to use
its own tracing event, from Alan.
2) Better libbpf support on older kernels, from Andrii.
3) Additional AF_XDP stats, from Ciara.
4) build time resolution of BTF IDs, from Jiri.
5) BPF_CGROUP_INET_SOCK_RELEASE hook, from Stanislav.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
The bpf helper bpf_trace_printk() uses trace_printk() under the hood.
This leads to an alarming warning message originating from trace
buffer allocation which occurs the first time a program using
bpf_trace_printk() is loaded.
We can instead create a trace event for bpf_trace_printk() and enable
it in-kernel when/if we encounter a program using the
bpf_trace_printk() helper. With this approach, trace_printk()
is not used directly and no warning message appears.
This work was started by Steven (see Link) and finished by Alan; added
Steven's Signed-off-by with his permission.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Signed-off-by: Alan Maguire <alan.maguire@oracle.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/r/20200628194334.6238b933@oasis.local.home
Link: https://lore.kernel.org/bpf/1594641154-18897-2-git-send-email-alan.maguire@oracle.com
Replace the open-coded version of receive_fd() with a call to the
new helper.
Thanks to Vamshi K Sthambamkadi <vamshi.k.sthambamkadi@gmail.com> for
catching a missed fput() in an earlier version of this patch.
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Reviewed-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
The sock counting (sock_update_netprioidx() and sock_update_classid())
was missing from pidfd's implementation of received fd installation. Add
a call to the new __receive_sock() helper.
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: netdev@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 8649c322f7 ("pid: Implement pidfd_getfd syscall")
Signed-off-by: Kees Cook <keescook@chromium.org>
This way the ID is resolved during compile time,
and we can remove the runtime name search.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-7-jolsa@kernel.org
Now when we moved the helpers btf_id arrays into .BTF_ids section,
we can remove the code that resolve those IDs in runtime.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-6-jolsa@kernel.org
Using BTF_ID_LIST macro to define lists for several helpers
using BTF arguments.
And running resolve_btfids on vmlinux elf object during linking,
so the .BTF_ids section gets the IDs resolved.
Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200711215329.41165-5-jolsa@kernel.org
The commit 625d344978 ("Revert "kernel/printk: add kmsg SEEK_CUR
handling"") reverted a change done to the return value in case a SEEK_CUR
operation was performed for kmsg buffer based on the fact that different
userspace apps were handling the new return value (-ESPIPE) in different
ways, breaking them.
At the same time -ESPIPE was the wrong decision because kmsg /does support/
seek() but doesn't follow the "normal" behavior userspace is used to.
Because of that and also considering the time -EINVAL has been used, it was
decided to keep this way to avoid more userspace breakage.
This patch adds an official statement to the kmsg documentation pointing to
the current return value for SEEK_CUR, -EINVAL, thus userspace libraries
and apps can refer to it for a definitive guide on what to expect.
Signed-off-by: Bruno Meneguele <bmeneg@redhat.com>
Reviewed-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200710174423.10480-1-bmeneg@redhat.com
I have a few KGDB-related fixes that I'd like to target for 5.8-rc5. They're
mostly fixes for build warnings, but there's also:
* Support for the qSupported and qXfer packets, which are necessary to pass
around GDB XML information which we need for the RISC-V GDB port to fully
function.
* Users can now select STRICT_KERNEL_RWX instead of forcing it on.
I know it's a bit late for rc5, as these are not critical it's not a big deal
if they don't make it in.
-----BEGIN PGP SIGNATURE-----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=kyQD
-----END PGP SIGNATURE-----
Merge tag 'riscv-for-linus-5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V fixes from Palmer Dabbelt:
"I have a few KGDB-related fixes. They're mostly fixes for build
warnings, but there's also:
- Support for the qSupported and qXfer packets, which are necessary
to pass around GDB XML information which we need for the RISC-V GDB
port to fully function.
- Users can now select STRICT_KERNEL_RWX instead of forcing it on"
* tag 'riscv-for-linus-5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux:
riscv: Avoid kgdb.h including gdb_xml.h to solve unused-const-variable warning
kgdb: Move the extern declaration kgdb_has_hit_break() to generic kgdb.h
riscv: Fix "no previous prototype" compile warning in kgdb.c file
riscv: enable the Kconfig prompt of STRICT_KERNEL_RWX
kgdb: enable arch to support XML packet.
Pull networking fixes from David Miller:
1) Restore previous behavior of CAP_SYS_ADMIN wrt loading networking
BPF programs, from Maciej Żenczykowski.
2) Fix dropped broadcasts in mac80211 code, from Seevalamuthu
Mariappan.
3) Slay memory leak in nl80211 bss color attribute parsing code, from
Luca Coelho.
4) Get route from skb properly in ip_route_use_hint(), from Miaohe Lin.
5) Don't allow anything other than ARPHRD_ETHER in llc code, from Eric
Dumazet.
6) xsk code dips too deeply into DMA mapping implementation internals.
Add dma_need_sync and use it. From Christoph Hellwig
7) Enforce power-of-2 for BPF ringbuf sizes. From Andrii Nakryiko.
8) Check for disallowed attributes when loading flow dissector BPF
programs. From Lorenz Bauer.
9) Correct packet injection to L3 tunnel devices via AF_PACKET, from
Jason A. Donenfeld.
10) Don't advertise checksum offload on ipa devices that don't support
it. From Alex Elder.
11) Resolve several issues in TCP MD5 signature support. Missing memory
barriers, bogus options emitted when using syncookies, and failure
to allow md5 key changes in established states. All from Eric
Dumazet.
12) Fix interface leak in hsr code, from Taehee Yoo.
13) VF reset fixes in hns3 driver, from Huazhong Tan.
14) Make loopback work again with ipv6 anycast, from David Ahern.
15) Fix TX starvation under high load in fec driver, from Tobias
Waldekranz.
16) MLD2 payload lengths not checked properly in bridge multicast code,
from Linus Lüssing.
17) Packet scheduler code that wants to find the inner protocol
currently only works for one level of VLAN encapsulation. Allow
Q-in-Q situations to work properly here, from Toke
Høiland-Jørgensen.
18) Fix route leak in l2tp, from Xin Long.
19) Resolve conflict between the sk->sk_user_data usage of bpf reuseport
support and various protocols. From Martin KaFai Lau.
20) Fix socket cgroup v2 reference counting in some situations, from
Cong Wang.
21) Cure memory leak in mlx5 connection tracking offload support, from
Eli Britstein.
* git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net: (146 commits)
mlxsw: pci: Fix use-after-free in case of failed devlink reload
mlxsw: spectrum_router: Remove inappropriate usage of WARN_ON()
net: macb: fix call to pm_runtime in the suspend/resume functions
net: macb: fix macb_suspend() by removing call to netif_carrier_off()
net: macb: fix macb_get/set_wol() when moving to phylink
net: macb: mark device wake capable when "magic-packet" property present
net: macb: fix wakeup test in runtime suspend/resume routines
bnxt_en: fix NULL dereference in case SR-IOV configuration fails
libbpf: Fix libbpf hashmap on (I)LP32 architectures
net/mlx5e: CT: Fix memory leak in cleanup
net/mlx5e: Fix port buffers cell size value
net/mlx5e: Fix 50G per lane indication
net/mlx5e: Fix CPU mapping after function reload to avoid aRFS RX crash
net/mlx5e: Fix VXLAN configuration restore after function reload
net/mlx5e: Fix usage of rcu-protected pointer
net/mxl5e: Verify that rpriv is not NULL
net/mlx5: E-Switch, Fix vlan or qos setting in legacy mode
net/mlx5: Fix eeprom support for SFP module
cgroup: Fix sock_cgroup_data on big-endian.
selftests: bpf: Fix detach from sockmap tests
...
The terminator for the mode 1 syscalls list was a 0, but that could be
a valid syscall number (e.g. x86_64 __NR_read). By luck, __NR_read was
listed first and the loop construct would not test it, so there was no
bug. However, this is fragile. Replace the terminator with -1 instead,
and make the variable name for mode 1 syscall lists more descriptive.
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Will Drewry <wad@chromium.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
When SECCOMP_IOCTL_NOTIF_ID_VALID was first introduced it had the wrong
direction flag set. While this isn't a big deal as nothing currently
enforces these bits in the kernel, it should be defined correctly. Fix
the define and provide support for the old command until it is no longer
needed for backward compatibility.
Fixes: 6a21cc50f0 ("seccomp: add a return code to trap to userspace")
Signed-off-by: Kees Cook <keescook@chromium.org>
We've been making heavy use of the seccomp notifier to intercept and
handle certain syscalls for containers. This patch allows a syscall
supervisor listening on a given notifier to be notified when a seccomp
filter has become unused.
A container is often managed by a singleton supervisor process the
so-called "monitor". This monitor process has an event loop which has
various event handlers registered. If the user specified a seccomp
profile that included a notifier for various syscalls then we also
register a seccomp notify even handler. For any container using a
separate pid namespace the lifecycle of the seccomp notifier is bound to
the init process of the pid namespace, i.e. when the init process exits
the filter must be unused.
If a new process attaches to a container we force it to assume a seccomp
profile. This can either be the same seccomp profile as the container
was started with or a modified one. If the attaching process makes use
of the seccomp notifier we will register a new seccomp notifier handler
in the monitor's event loop. However, when the attaching process exits
we can't simply delete the handler since other child processes could've
been created (daemons spawned etc.) that have inherited the seccomp
filter and so we need to keep the seccomp notifier fd alive in the event
loop. But this is problematic since we don't get a notification when the
seccomp filter has become unused and so we currently never remove the
seccomp notifier fd from the event loop and just keep accumulating fds
in the event loop. We've had this issue for a while but it has recently
become more pressing as more and larger users make use of this.
To fix this, we introduce a new "users" reference counter that tracks any
tasks and dependent filters making use of a filter. When a notifier is
registered waiting tasks will be notified that the filter is now empty
by receiving a (E)POLLHUP event.
The concept in this patch introduces is the same as for signal_struct,
i.e. reference counting for life-cycle management is decoupled from
reference counting taks using the object. There's probably some trickery
possible but the second counter is just the correct way of doing this
IMHO and has precedence.
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matt Denton <mpdenton@google.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Jann Horn <jannh@google.com>
Cc: Chris Palmer <palmer@google.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Robert Sesek <rsesek@google.com>
Cc: Jeffrey Vander Stoep <jeffv@google.com>
Cc: Linux Containers <containers@lists.linux-foundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200531115031.391515-3-christian.brauner@ubuntu.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Lift the wait_queue from struct notification into struct seccomp_filter.
This is cleaner overall and lets us avoid having to take the notifier
mutex in the future for EPOLLHUP notifications since we need to neither
read nor modify the notifier specific aspects of the seccomp filter. In
the exit path I'd very much like to avoid having to take the notifier mutex
for each filter in the task's filter hierarchy.
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matt Denton <mpdenton@google.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Jann Horn <jannh@google.com>
Cc: Chris Palmer <palmer@google.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Robert Sesek <rsesek@google.com>
Cc: Jeffrey Vander Stoep <jeffv@google.com>
Cc: Linux Containers <containers@lists.linux-foundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
The seccomp filter used to be released in free_task() which is called
asynchronously via call_rcu() and assorted mechanisms. Since we need
to inform tasks waiting on the seccomp notifier when a filter goes empty
we will notify them as soon as a task has been marked fully dead in
release_task(). To not split seccomp cleanup into two parts, move
filter release out of free_task() and into release_task() after we've
unhashed struct task from struct pid, exited signals, and unlinked it
from the threadgroups' thread list. We'll put the empty filter
notification infrastructure into it in a follow up patch.
This also renames put_seccomp_filter() to seccomp_filter_release() which
is a more descriptive name of what we're doing here especially once
we've added the empty filter notification mechanism in there.
We're also NULL-ing the task's filter tree entrypoint which seems
cleaner than leaving a dangling pointer in there. Note that this shouldn't
need any memory barriers since we're calling this when the task is in
release_task() which means it's EXIT_DEAD. So it can't modify its seccomp
filters anymore. You can also see this from the point where we're calling
seccomp_filter_release(). It's after __exit_signal() and at this point,
tsk->sighand will already have been NULLed which is required for
thread-sync and filter installation alike.
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matt Denton <mpdenton@google.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Jann Horn <jannh@google.com>
Cc: Chris Palmer <palmer@google.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Robert Sesek <rsesek@google.com>
Cc: Jeffrey Vander Stoep <jeffv@google.com>
Cc: Linux Containers <containers@lists.linux-foundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200531115031.391515-2-christian.brauner@ubuntu.com
Signed-off-by: Kees Cook <keescook@chromium.org>
Naming the lifetime counter of a seccomp filter "usage" suggests a
little too strongly that its about tasks that are using this filter
while it also tracks other references such as the user notifier or
ptrace. This also updates the documentation to note this fact.
We'll be introducing an actual usage counter in a follow-up patch.
Cc: Tycho Andersen <tycho@tycho.ws>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matt Denton <mpdenton@google.com>
Cc: Sargun Dhillon <sargun@sargun.me>
Cc: Jann Horn <jannh@google.com>
Cc: Chris Palmer <palmer@google.com>
Cc: Aleksa Sarai <cyphar@cyphar.com>
Cc: Robert Sesek <rsesek@google.com>
Cc: Jeffrey Vander Stoep <jeffv@google.com>
Cc: Linux Containers <containers@lists.linux-foundation.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Link: https://lore.kernel.org/r/20200531115031.391515-1-christian.brauner@ubuntu.com
Signed-off-by: Kees Cook <keescook@chromium.org>
This adds a helper which can iterate through a seccomp_filter to
find a notification matching an ID. It removes several replicated
chunks of code.
Signed-off-by: Sargun Dhillon <sargun@sargun.me>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Tycho Andersen <tycho@tycho.ws>
Cc: Matt Denton <mpdenton@google.com>
Cc: Kees Cook <keescook@google.com>,
Cc: Jann Horn <jannh@google.com>,
Cc: Robert Sesek <rsesek@google.com>,
Cc: Chris Palmer <palmer@google.com>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Tycho Andersen <tycho@tycho.ws>
Link: https://lore.kernel.org/r/20200601112532.150158-1-sargun@sargun.me
Signed-off-by: Kees Cook <keescook@chromium.org>
A common question asked when debugging seccomp filters is "how many
filters are attached to your process?" Provide a way to easily answer
this question through /proc/$pid/status with a "Seccomp_filters" line.
Signed-off-by: Kees Cook <keescook@chromium.org>
- add a warning when the atomic pool is depleted (David Rientjes)
- protect the parameters of the new scatterlist helper macros
(Marek Szyprowski )
-----BEGIN PGP SIGNATURE-----
iQI/BAABCgApFiEEgdbnc3r/njty3Iq9D55TZVIEUYMFAl8IjBILHGhjaEBsc3Qu
ZGUACgkQD55TZVIEUYN10RAAjCGeb2ImNmGHgqZEbJ5KM99g/gVeGJO2aUOLQWCx
qr3Jx0PX6TaGi/tg4OMJFwA8oErHh6bZO1OWVp7PShmeEHRdRp+FPmcb0PzRM1pO
gNxgouJIj+B47enkFwRjLpiST5YVoP90Sn61I8Vr9hiC88TaLho0Kj2hkvTcKRln
NCahkT9NTQpoC1iFR+lMje1yodEzWum3+aAEmjIaebeMJor1v8RRGkYXJASdD1V2
whchfZCWM6Jhr9PUAL3NnTbQXccI7qOkCCsxssW652SysIN6dV8XmBmoH/VUC5QE
soScl93T0EZvBdUreEvKSjVO3BOCRuemuzQ9myFk4c/olKGqQO675G1sCs9RIawz
UEAtWEWYC/CluKvzjJuJl2pGmfNRuazsylLA6WDQGqQoe8uJ/9qKKpCr9jRn3shl
dUccyFQWrmXrh76qXPvB05D0/qb4JNVhyXYLiD8DhzR3DlH1d5z52TWDT9g/J84Q
usq69gwZq65MZYMHWRlRRXYdEuvQxgEZvl2ecYA/ZaW1wh6XYGBCQI5CtG5E2sOP
8THs5E+u1PQaJWqdIR57xCuNxpWS+r6nv0N7z4vIQtwVkXPO3lS7aVNClIOY1u5/
m7SEeJ4ZBtVZsA4nQbG3sxAiA1GT8nm5JugwfOIgmMyxrpRbNWj8IrIe49Ckbhqa
YZQ=
=KI5i
-----END PGP SIGNATURE-----
Merge tag 'dma-mapping-5.8-5' of git://git.infradead.org/users/hch/dma-mapping
Pull dma-mapping fixes from Christoph Hellwig:
- add a warning when the atomic pool is depleted (David Rientjes)
- protect the parameters of the new scatterlist helper macros (Marek
Szyprowski )
* tag 'dma-mapping-5.8-5' of git://git.infradead.org/users/hch/dma-mapping:
scatterlist: protect parameters of the sg_table related macros
dma-mapping: warn when coherent pool is depleted
Currently all IRQ-tracking state is in task_struct, this means that
task_struct needs to be defined before we use it.
Especially for lockdep_assert_irq*() this can lead to header-hell.
Move the hardirq state into per-cpu variables to avoid the task_struct
dependency.
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200623083721.512673481@infradead.org
There is no reason not to always, accurately, track IRQ state.
This change also makes IRQ state tracking ignore lockdep_off().
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200623083721.155449112@infradead.org
The new IRQ state tracking code does not honor lockdep_off(), and as
such we should again permit tracing by using non-raw functions in
core.c. Update the lockdep_off() comment in report.c, to reflect the
fact there is still a potential risk of deadlock due to using printk()
from scheduler code.
Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200624113246.GA170324@elver.google.com
Replace the existing ringbuffer usage and implementation with
lockless ringbuffer usage. Even though the new ringbuffer does not
require locking, all existing locking is left in place. Therefore,
this change is purely replacing the underlining ringbuffer.
Changes that exist due to the ringbuffer replacement:
- The VMCOREINFO has been updated for the new structures.
- Dictionary data is now stored in a separate data buffer from the
human-readable messages. The dictionary data buffer is set to the
same size as the message buffer. Therefore, the total required
memory for both dictionary and message data is
2 * (2 ^ CONFIG_LOG_BUF_SHIFT) for the initial static buffers and
2 * log_buf_len (the kernel parameter) for the dynamic buffers.
- Record meta-data is now stored in a separate array of descriptors.
This is an additional 72 * (2 ^ (CONFIG_LOG_BUF_SHIFT - 5)) bytes
for the static array and 72 * (log_buf_len >> 5) bytes for the
dynamic array.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200709132344.760-5-john.ogness@linutronix.de
This reverts commit 3ac37a93fa.
This optimization will not apply once the transition to a lockless
printk is complete. Rather than porting this optimization through
the transition only to remove it anyway, just revert it now to
simplify the transition.
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Acked-by: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200709132344.760-4-john.ogness@linutronix.de
Introduce a multi-reader multi-writer lockless ringbuffer for storing
the kernel log messages. Readers and writers may use their API from
any context (including scheduler and NMI). This ringbuffer will make
it possible to decouple printk() callers from any context, locking,
or console constraints. It also makes it possible for readers to have
full access to the ringbuffer contents at any time and context (for
example from any panic situation).
The printk_ringbuffer is made up of 3 internal ringbuffers:
desc_ring:
A ring of descriptors. A descriptor contains all record meta data
(sequence number, timestamp, loglevel, etc.) as well as internal state
information about the record and logical positions specifying where in
the other ringbuffers the text and dictionary strings are located.
text_data_ring:
A ring of data blocks. A data block consists of an unsigned long
integer (ID) that maps to a desc_ring index followed by the text
string of the record.
dict_data_ring:
A ring of data blocks. A data block consists of an unsigned long
integer (ID) that maps to a desc_ring index followed by the dictionary
string of the record.
The internal state information of a descriptor is the key element to
allow readers and writers to locklessly synchronize access to the data.
Co-developed-by: Petr Mladek <pmladek@suse.com>
Signed-off-by: John Ogness <john.ogness@linutronix.de>
Reviewed-by: Petr Mladek <pmladek@suse.com>
Reviewed-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Petr Mladek <pmladek@suse.com>
Link: https://lore.kernel.org/r/20200709132344.760-3-john.ogness@linutronix.de
The XML packet could be supported by required architecture if the
architecture defines CONFIG_HAVE_ARCH_KGDB_QXFER_PKT and implement its own
kgdb_arch_handle_qxfer_pkt(). Except for the kgdb_arch_handle_qxfer_pkt(),
the architecture also needs to record the feature supported by gdb stub
into the kgdb_arch_gdb_stub_feature, and these features will be reported
to host gdb when gdb stub receives the qSupported packet.
Signed-off-by: Vincent Chen <vincent.chen@sifive.com>
Acked-by: Daniel Thompson <daniel.thompson@linaro.org>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
Static defined trace_event->type stops at (__TRACE_LAST_TYPE - 1) and
dynamic trace_event->type starts from (__TRACE_LAST_TYPE + 1).
To save one trace_event->type index, let's use __TRACE_LAST_TYPE.
Link: https://lkml.kernel.org/r/20200703020612.12930-3-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
The value to be used and compared in trace_search_list() is "last + 1".
Let's just define next to be "last + 1" instead of doing the addition
each time.
Link: https://lkml.kernel.org/r/20200703020612.12930-2-richard.weiyang@linux.alibaba.com
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Several users of kallsyms_show_value() were performing checks not
during "open". Refactor everything needed to gain proper checks against
file->f_cred for modules, kprobes, and bpf.
-----BEGIN PGP SIGNATURE-----
iQJKBAABCgA0FiEEpcP2jyKd1g9yPm4TiXL039xtwCYFAl8GUbMWHGtlZXNjb29r
QGNocm9taXVtLm9yZwAKCRCJcvTf3G3AJohnD/9VsPsAMV+8lhsPvkcuW/DkTcAY
qUEzsXU3v06gJ0Z/1lBKtisJ6XmD93wWcZCTFvJ0S8vR3yLZvOVfToVjCMO32Trc
4ZkWTPwpvfeLug6T6CcI2ukQdZ/opI1cSabqGl79arSBgE/tsghwrHuJ8Exkz4uq
0b7i8nZa+RiTezwx4EVeGcg6Dv1tG5UTG2VQvD/+QGGKneBlrlaKlI885N/6jsHa
KxvB7+8ES1pnfGYZenx+RxMdljNrtyptbQEU8gyvoV5YR7635gjZsVsPwWANJo+4
EGcFFpwWOAcVQaC3dareLTM8nVngU6Wl3Rd7JjZtjvtZba8DdCn669R34zDGXbiP
+1n1dYYMSMBeqVUbAQfQyLD0pqMIHdwQj2TN8thSGccr2o3gNk6AXgYq0aYm8IBf
xDCvAansJw9WqmxErIIsD4BFkMqF7MjH3eYZxwCPWSrKGDvKxQSPV5FarnpDC9U7
dYCWVxNPmtn+unC/53yXjEcBepKaYgNR7j5G7uOfkHvU43Bd5demzLiVJ10D8abJ
ezyErxxEqX2Gr7JR2fWv7iBbULJViqcAnYjdl0y0NgK/hftt98iuge6cZmt1z6ai
24vI3X4VhvvVN5/f64cFDAdYtMRUtOo2dmxdXMid1NI07Mj2qFU1MUwb8RHHlxbK
8UegV2zcrBghnVuMkw==
=ib5Q
-----END PGP SIGNATURE-----
Merge tag 'kallsyms_show_value-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux
Pull kallsyms fix from Kees Cook:
"Refactor kallsyms_show_value() users for correct cred.
I'm not delighted by the timing of getting these changes to you, but
it does fix a handful of kernel address exposures, and no one has
screamed yet at the patches.
Several users of kallsyms_show_value() were performing checks not
during "open". Refactor everything needed to gain proper checks
against file->f_cred for modules, kprobes, and bpf"
* tag 'kallsyms_show_value-v5.8-rc5' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux:
selftests: kmod: Add module address visibility test
bpf: Check correct cred for CAP_SYSLOG in bpf_dump_raw_ok()
kprobes: Do not expose probe addresses to non-CAP_SYSLOG
module: Do not expose section addresses to non-CAP_SYSLOG
module: Refactor section attr into bin attribute
kallsyms: Refactor kallsyms_show_value() to take cred
bpf_sk_reuseport_detach is currently called when sk->sk_user_data
is not NULL. It is incorrect because sk->sk_user_data may not be
managed by the bpf's reuseport_array. It has been reported in [1] that,
the bpf_sk_reuseport_detach() which is called from udp_lib_unhash() has
corrupted the sk_user_data managed by l2tp.
This patch solves it by using another bit (defined as SK_USER_DATA_BPF)
of the sk_user_data pointer value. It marks that a sk_user_data is
managed/owned by BPF.
The patch depends on a PTRMASK introduced in
commit f1ff5ce2cd ("net, sk_msg: Clear sk_user_data pointer on clone if tagged").
[ Note: sk->sk_user_data is used by bpf's reuseport_array only when a sk is
added to the bpf's reuseport_array.
i.e. doing setsockopt(SO_REUSEPORT) and having "sk->sk_reuseport == 1"
alone will not stop sk->sk_user_data being used by other means. ]
[1]: https://lore.kernel.org/netdev/20200706121259.GA20199@katalix.com/
Fixes: 5dc4c4b7d4 ("bpf: Introduce BPF_MAP_TYPE_REUSEPORT_SOCKARRAY")
Reported-by: James Chapman <jchapman@katalix.com>
Reported-by: syzbot+9f092552ba9a5efca5df@syzkaller.appspotmail.com
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: James Chapman <jchapman@katalix.com>
Acked-by: James Chapman <jchapman@katalix.com>
Link: https://lore.kernel.org/bpf/20200709061110.4019316-1-kafai@fb.com
It makes little sense for copying sk_user_data of reuseport_array during
sk_clone_lock(). This patch reuses the SK_USER_DATA_NOCOPY bit introduced in
commit f1ff5ce2cd ("net, sk_msg: Clear sk_user_data pointer on clone if tagged").
It is used to mark the sk_user_data is not supposed to be copied to its clone.
Although the cloned sk's sk_user_data will not be used/freed in
bpf_sk_reuseport_detach(), this change can still allow the cloned
sk's sk_user_data to be used by some other means.
Freeing the reuseport_array's sk_user_data does not require a rcu grace
period. Thus, the existing rcu_assign_sk_user_data_nocopy() is not
used.
Fixes: 5dc4c4b7d4 ("bpf: Introduce BPF_MAP_TYPE_REUSEPORT_SOCKARRAY")
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20200709061104.4018798-1-kafai@fb.com
When a timer is enqueued with a negative delta (ie: expiry is below
base->clk), it gets added to the wheel as expiring now (base->clk).
Yet the value that gets stored in base->next_expiry, while calling
trigger_dyntick_cpu(), is the initial timer->expires value. The
resulting state becomes:
base->next_expiry < base->clk
On the next timer enqueue, forward_timer_base() may accidentally
rewind base->clk. As a possible outcome, timers may expire way too
early, the worst case being that the highest wheel levels get spuriously
processed again.
To prevent from that, make sure that base->next_expiry doesn't get below
base->clk.
Fixes: a683f390b9 ("timers: Forward the wheel clock whenever possible")
Signed-off-by: Frederic Weisbecker <frederic@kernel.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de>
Tested-by: Juri Lelli <juri.lelli@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200703010657.2302-1-frederic@kernel.org
The LSM_AUDIT_DATA_* records for PATH, FILE, IOCTL_OP, DENTRY and INODE
are incomplete without the task context of the AUDIT Current Working
Directory record. Add it.
This record addition can't use audit_dummy_context to determine whether
or not to store the record information since the LSM_AUDIT_DATA_*
records are initiated by various LSMs independent of any audit rules.
context->in_syscall is used to determine if it was called in user
context like audit_getname.
Please see the upstream issue
https://github.com/linux-audit/audit-kernel/issues/96
Adapted from Vladis Dronov's v2 patch.
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
When evaluating access control over kallsyms visibility, credentials at
open() time need to be used, not the "current" creds (though in BPF's
case, this has likely always been the same). Plumb access to associated
file->f_cred down through bpf_dump_raw_ok() and its callers now that
kallsysm_show_value() has been refactored to take struct cred.
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: bpf@vger.kernel.org
Cc: stable@vger.kernel.org
Fixes: 7105e828c0 ("bpf: allow for correlation of maps and helpers in dump")
Signed-off-by: Kees Cook <keescook@chromium.org>
The kprobe show() functions were using "current"'s creds instead
of the file opener's creds for kallsyms visibility. Fix to use
seq_file->file->f_cred.
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: stable@vger.kernel.org
Fixes: 81365a947d ("kprobes: Show address of kprobes if kallsyms does")
Fixes: ffb9bd68eb ("kprobes: Show blacklist addresses as same as kallsyms does")
Signed-off-by: Kees Cook <keescook@chromium.org>
In order to gain access to the open file's f_cred for kallsym visibility
permission checks, refactor the module section attributes to use the
bin_attribute instead of attribute interface. Additionally removes the
redundant "name" struct member.
Cc: stable@vger.kernel.org
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Tested-by: Jessica Yu <jeyu@kernel.org>
Acked-by: Jessica Yu <jeyu@kernel.org>
Signed-off-by: Kees Cook <keescook@chromium.org>
In order to perform future tests against the cred saved during open(),
switch kallsyms_show_value() to operate on a cred, and have all current
callers pass current_cred(). This makes it very obvious where callers
are checking the wrong credential in their "read" contexts. These will
be fixed in the coming patches.
Additionally switch return value to bool, since it is always used as a
direct permission check, not a 0-on-success, negative-on-error style
function return.
Cc: stable@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
There are cases where a guest tries to switch spinlocks to bare metal
behavior (e.g. by setting "xen_nopvspin" on XEN platform and
"hv_nopvspin" on HYPER_V).
That feature is missed on KVM, add a new parameter "nopvspin" to disable
PV spinlocks for KVM guest.
The new 'nopvspin' parameter will also replace Xen and Hyper-V specific
parameters in future patches.
Define variable nopvsin as global because it will be used in future
patches as above.
Signed-off-by: Zhenzhong Duan <zhenzhong.duan@oracle.com>
Reviewed-by: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Radim Krcmar <rkrcmar@redhat.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: Wanpeng Li <wanpengli@tencent.com>
Cc: Jim Mattson <jmattson@google.com>
Cc: Joerg Roedel <joro@8bytes.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Add a bare tracepoint trace_sched_update_nr_running_tp which tracks
->nr_running CPU's rq. This is used to accurately trace this data and
provide a visualization of scheduler imbalances in, for example, the
form of a heat map. The tracepoint is accessed by loading an external
kernel module. An example module (forked from Qais' module and including
the pelt related tracepoints) can be found at:
https://github.com/auldp/tracepoints-helpers.git
A script to turn the trace-cmd report output into a heatmap plot can be
found at:
https://github.com/jirvoz/plot-nr-running
The tracepoints are added to add_nr_running() and sub_nr_running() which
are in kernel/sched/sched.h. In order to avoid CREATE_TRACE_POINTS in
the header a wrapper call is used and the trace/events/sched.h include
is moved before sched.h in kernel/sched/core.
Signed-off-by: Phil Auld <pauld@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200629192303.GC120228@lorien.usersys.redhat.com
There is a report that when uclamp is enabled, a netperf UDP test
regresses compared to a kernel compiled without uclamp.
https://lore.kernel.org/lkml/20200529100806.GA3070@suse.de/
While investigating the root cause, there were no sign that the uclamp
code is doing anything particularly expensive but could suffer from bad
cache behavior under certain circumstances that are yet to be
understood.
https://lore.kernel.org/lkml/20200616110824.dgkkbyapn3io6wik@e107158-lin/
To reduce the pressure on the fast path anyway, add a static key that is
by default will skip executing uclamp logic in the
enqueue/dequeue_task() fast path until it's needed.
As soon as the user start using util clamp by:
1. Changing uclamp value of a task with sched_setattr()
2. Modifying the default sysctl_sched_util_clamp_{min, max}
3. Modifying the default cpu.uclamp.{min, max} value in cgroup
We flip the static key now that the user has opted to use util clamp.
Effectively re-introducing uclamp logic in the enqueue/dequeue_task()
fast path. It stays on from that point forward until the next reboot.
This should help minimize the effect of util clamp on workloads that
don't need it but still allow distros to ship their kernels with uclamp
compiled in by default.
SCHED_WARN_ON() in uclamp_rq_dec_id() was removed since now we can end
up with unbalanced call to uclamp_rq_dec_id() if we flip the key while
a task is running in the rq. Since we know it is harmless we just
quietly return if we attempt a uclamp_rq_dec_id() when
rq->uclamp[].bucket[].tasks is 0.
In schedutil, we introduce a new uclamp_is_enabled() helper which takes
the static key into account to ensure RT boosting behavior is retained.
The following results demonstrates how this helps on 2 Sockets Xeon E5
2x10-Cores system.
nouclamp uclamp uclamp-static-key
Hmean send-64 162.43 ( 0.00%) 157.84 * -2.82%* 163.39 * 0.59%*
Hmean send-128 324.71 ( 0.00%) 314.78 * -3.06%* 326.18 * 0.45%*
Hmean send-256 641.55 ( 0.00%) 628.67 * -2.01%* 648.12 * 1.02%*
Hmean send-1024 2525.28 ( 0.00%) 2448.26 * -3.05%* 2543.73 * 0.73%*
Hmean send-2048 4836.14 ( 0.00%) 4712.08 * -2.57%* 4867.69 * 0.65%*
Hmean send-3312 7540.83 ( 0.00%) 7425.45 * -1.53%* 7621.06 * 1.06%*
Hmean send-4096 9124.53 ( 0.00%) 8948.82 * -1.93%* 9276.25 * 1.66%*
Hmean send-8192 15589.67 ( 0.00%) 15486.35 * -0.66%* 15819.98 * 1.48%*
Hmean send-16384 26386.47 ( 0.00%) 25752.25 * -2.40%* 26773.74 * 1.47%*
The perf diff between nouclamp and uclamp-static-key when uclamp is
disabled in the fast path:
8.73% -1.55% [kernel.kallsyms] [k] try_to_wake_up
0.07% +0.04% [kernel.kallsyms] [k] deactivate_task
0.13% -0.02% [kernel.kallsyms] [k] activate_task
The diff between nouclamp and uclamp-static-key when uclamp is enabled
in the fast path:
8.73% -0.72% [kernel.kallsyms] [k] try_to_wake_up
0.13% +0.39% [kernel.kallsyms] [k] activate_task
0.07% +0.38% [kernel.kallsyms] [k] deactivate_task
Fixes: 69842cba9a ("sched/uclamp: Add CPU's clamp buckets refcounting")
Reported-by: Mel Gorman <mgorman@suse.de>
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://lkml.kernel.org/r/20200630112123.12076-3-qais.yousef@arm.com
struct uclamp_rq was zeroed out entirely in assumption that in the first
call to uclamp_rq_inc() they'd be initialized correctly in accordance to
default settings.
But when next patch introduces a static key to skip
uclamp_rq_{inc,dec}() until userspace opts in to use uclamp, schedutil
will fail to perform any frequency changes because the
rq->uclamp[UCLAMP_MAX].value is zeroed at init and stays as such. Which
means all rqs are capped to 0 by default.
Fix it by making sure we do proper initialization at init without
relying on uclamp_rq_inc() doing it later.
Fixes: 69842cba9a ("sched/uclamp: Add CPU's clamp buckets refcounting")
Signed-off-by: Qais Yousef <qais.yousef@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Valentin Schneider <valentin.schneider@arm.com>
Tested-by: Lukasz Luba <lukasz.luba@arm.com>
Link: https://lkml.kernel.org/r/20200630112123.12076-2-qais.yousef@arm.com
For some mysterious reason GCC-4.9 has a 64 byte section alignment for
structures, all other GCC versions (and Clang) tested (including 4.8
and 5.0) are fine with the 32 bytes alignment.
Getting this right is important for the new SCHED_DATA macro that
creates an explicitly ordered array of 'struct sched_class' in the
linker script and expect pointer arithmetic to work.
Fixes: c3a340f7e7 ("sched: Have sched_class_highest define by vmlinux.lds.h")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200630144905.GX4817@hirez.programming.kicks-ass.net
Currently, the PMU specific data task_ctx_data is allocated by the
function kzalloc() in the perf generic code. When there is no specific
alignment requirement for the task_ctx_data, the method works well for
now. However, there will be a problem once a specific alignment
requirement is introduced in future features, e.g., the Architecture LBR
XSAVE feature requires 64-byte alignment. If the specific alignment
requirement is not fulfilled, the XSAVE family of instructions will fail
to save/restore the xstate to/from the task_ctx_data.
The function kzalloc() itself only guarantees a natural alignment. A
new method to allocate the task_ctx_data has to be introduced, which
has to meet the requirements as below:
- must be a generic method can be used by different architectures,
because the allocation of the task_ctx_data is implemented in the
perf generic code;
- must be an alignment-guarantee method (The alignment requirement is
not changed after the boot);
- must be able to allocate/free a buffer (smaller than a page size)
dynamically;
- should not cause extra CPU overhead or space overhead.
Several options were considered as below:
- One option is to allocate a larger buffer for task_ctx_data. E.g.,
ptr = kmalloc(size + alignment, GFP_KERNEL);
ptr &= ~(alignment - 1);
This option causes space overhead.
- Another option is to allocate the task_ctx_data in the PMU specific
code. To do so, several function pointers have to be added. As a
result, both the generic structure and the PMU specific structure
will become bigger. Besides, extra function calls are added when
allocating/freeing the buffer. This option will increase both the
space overhead and CPU overhead.
- The third option is to use a kmem_cache to allocate a buffer for the
task_ctx_data. The kmem_cache can be created with a specific alignment
requirement by the PMU at boot time. A new pointer for kmem_cache has
to be added in the generic struct pmu, which would be used to
dynamically allocate a buffer for the task_ctx_data at run time.
Although the new pointer is added to the struct pmu, the existing
variable task_ctx_size is not required anymore. The size of the
generic structure is kept the same.
The third option which meets all the aforementioned requirements is used
to replace kzalloc() for the PMU specific data allocation. A later patch
will remove the kzalloc() method and the related variables.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-17-git-send-email-kan.liang@linux.intel.com
The method to allocate/free the task_ctx_data is going to be changed in
the following patch. Currently, the task_ctx_data is allocated/freed in
several different places. To avoid repeatedly modifying the same codes
in several different places, alloc_task_ctx_data() and
free_task_ctx_data() are factored out to allocate/free the
task_ctx_data. The modification only needs to be applied once.
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-16-git-send-email-kan.liang@linux.intel.com
While integrating rseq into glibc and replacing glibc's sched_getcpu
implementation with rseq, glibc's tests discovered an issue with
incorrect __rseq_abi.cpu_id field value right after the first time
a newly created process issues sched_setaffinity.
For the records, it triggers after building glibc and running tests, and
then issuing:
for x in {1..2000} ; do posix/tst-affinity-static & done
and shows up as:
error: Unexpected CPU 2, expected 0
error: Unexpected CPU 2, expected 0
error: Unexpected CPU 2, expected 0
error: Unexpected CPU 2, expected 0
error: Unexpected CPU 138, expected 0
error: Unexpected CPU 138, expected 0
error: Unexpected CPU 138, expected 0
error: Unexpected CPU 138, expected 0
This is caused by the scheduler invoking __set_task_cpu() directly from
sched_fork() and wake_up_new_task(), thus bypassing rseq_migrate() which
is done by set_task_cpu().
Add the missing rseq_migrate() to both functions. The only other direct
use of __set_task_cpu() is done by init_idle(), which does not involve a
user-space task.
Based on my testing with the glibc test-case, just adding rseq_migrate()
to wake_up_new_task() is sufficient to fix the observed issue. Also add
it to sched_fork() to keep things consistent.
The reason why this never triggered so far with the rseq/basic_test
selftest is unclear.
The current use of sched_getcpu(3) does not typically require it to be
always accurate. However, use of the __rseq_abi.cpu_id field within rseq
critical sections requires it to be accurate. If it is not accurate, it
can cause corruption in the per-cpu data targeted by rseq critical
sections in user-space.
Reported-By: Florian Weimer <fweimer@redhat.com>
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-By: Florian Weimer <fweimer@redhat.com>
Cc: stable@vger.kernel.org # v4.18+
Link: https://lkml.kernel.org/r/20200707201505.2632-1-mathieu.desnoyers@efficios.com
The recent commit:
c6e7bd7afa ("sched/core: Optimize ttwu() spinning on p->on_cpu")
moved these lines in ttwu():
p->sched_contributes_to_load = !!task_contributes_to_load(p);
p->state = TASK_WAKING;
up before:
smp_cond_load_acquire(&p->on_cpu, !VAL);
into the 'p->on_rq == 0' block, with the thinking that once we hit
schedule() the current task cannot change it's ->state anymore. And
while this is true, it is both incorrect and flawed.
It is incorrect in that we need at least an ACQUIRE on 'p->on_rq == 0'
to avoid weak hardware from re-ordering things for us. This can fairly
easily be achieved by relying on the control-dependency already in
place.
The second problem, which makes the flaw in the original argument, is
that while schedule() will not change prev->state, it will read it a
number of times (arguably too many times since it's marked volatile).
The previous condition 'p->on_cpu == 0' was sufficient because that
indicates schedule() has completed, and will no longer read
prev->state. So now the trick is to make this same true for the (much)
earlier 'prev->on_rq == 0' case.
Furthermore, in order to make the ordering stick, the 'prev->on_rq = 0'
assignment needs to he a RELEASE, but adding additional ordering to
schedule() is an unwelcome proposition at the best of times, doubly so
for mere accounting.
Luckily we can push the prev->state load up before rq->lock, with the
only caveat that we then have to re-read the state after. However, we
know that if it changed, we no longer have to worry about the blocking
path. This gives us the required ordering, if we block, we did the
prev->state load before an (effective) smp_mb() and the p->on_rq store
needs not change.
With this we end up with the effective ordering:
LOAD p->state LOAD-ACQUIRE p->on_rq == 0
MB
STORE p->on_rq, 0 STORE p->state, TASK_WAKING
which ensures the TASK_WAKING store happens after the prev->state
load, and all is well again.
Fixes: c6e7bd7afa ("sched/core: Optimize ttwu() spinning on p->on_cpu")
Reported-by: Dave Jones <davej@codemonkey.org.uk>
Reported-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Dave Jones <davej@codemonkey.org.uk>
Tested-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Link: https://lkml.kernel.org/r/20200707102957.GN117543@hirez.programming.kicks-ass.net
So far setns() was missing time namespace support. This was partially due
to it simply not being implemented but also because vdso_join_timens()
could still fail which made switching to multiple namespaces atomically
problematic. This is now fixed so support CLONE_NEWTIME with setns()
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Dmitry Safonov <dima@arista.com>
Link: https://lore.kernel.org/r/20200706154912.3248030-4-christian.brauner@ubuntu.com
Wrap the calls to timens_set_vvar_page() and vdso_join_timens() in
timens_on_fork() and timens_install() in a new timens_commit() helper.
We'll use this helper in a follow-up patch in nsproxy too.
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dmitry Safonov <dima@arista.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20200706154912.3248030-3-christian.brauner@ubuntu.com
As discussed on-list (cf. [1]), in order to make setns() support time
namespaces when attaching to multiple namespaces at once properly we
need to tweak vdso_join_timens() to always succeed. So switch
vdso_join_timens() to using a read lock and replacing
mmap_write_lock_killable() to mmap_read_lock() as we discussed.
Last cycle setns() was changed to support attaching to multiple namespaces
atomically. This requires all namespaces to have a point of no return where
they can't fail anymore. Specifically, <namespace-type>_install() is
allowed to perform permission checks and install the namespace into the new
struct nsset that it has been given but it is not allowed to make visible
changes to the affected task. Once <namespace-type>_install() returns
anything that the given namespace type requires to be setup in addition
needs to ideally be done in a function that can't fail or if it fails the
failure is not fatal. For time namespaces the relevant functions that fall
into this category are timens_set_vvar_page() and vdso_join_timens().
Currently the latter can fail but doesn't need to. With this we can go on
to implement a timens_commit() helper in a follow up patch to be used by
setns().
[1]: https://lore.kernel.org/lkml/20200611110221.pgd3r5qkjrjmfqa2@wittgenstein
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Reviewed-by: Andrei Vagin <avagin@gmail.com>
Cc: Will Deacon <will@kernel.org>
Cc: Vincenzo Frascino <vincenzo.frascino@arm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dmitry Safonov <dima@arista.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: https://lore.kernel.org/r/20200706154912.3248030-2-christian.brauner@ubuntu.com
Sometimes it's handy to know when the socket gets freed. In
particular, we'd like to try to use a smarter allocation of
ports for bpf_bind and explore the possibility of limiting
the number of SOCK_DGRAM sockets the process can have.
Implement BPF_CGROUP_INET_SOCK_RELEASE hook that triggers on
inet socket release. It triggers only for userspace sockets
(not in-kernel ones) and therefore has the same semantics as
the existing BPF_CGROUP_INET_SOCK_CREATE.
Signed-off-by: Stanislav Fomichev <sdf@google.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200706230128.4073544-2-sdf@google.com
When we clone a socket in sk_clone_lock(), its sk_cgrp_data is
copied, so the cgroup refcnt must be taken too. And, unlike the
sk_alloc() path, sock_update_netprioidx() is not called here.
Therefore, it is safe and necessary to grab the cgroup refcnt
even when cgroup_sk_alloc is disabled.
sk_clone_lock() is in BH context anyway, the in_interrupt()
would terminate this function if called there. And for sk_alloc()
skcd->val is always zero. So it's safe to factor out the code
to make it more readable.
The global variable 'cgroup_sk_alloc_disabled' is used to determine
whether to take these reference counts. It is impossible to make
the reference counting correct unless we save this bit of information
in skcd->val. So, add a new bit there to record whether the socket
has already taken the reference counts. This obviously relies on
kmalloc() to align cgroup pointers to at least 4 bytes,
ARCH_KMALLOC_MINALIGN is certainly larger than that.
This bug seems to be introduced since the beginning, commit
d979a39d72 ("cgroup: duplicate cgroup reference when cloning sockets")
tried to fix it but not compeletely. It seems not easy to trigger until
the recent commit 090e28b229
("netprio_cgroup: Fix unlimited memory leak of v2 cgroups") was merged.
Fixes: bd1060a1d6 ("sock, cgroup: add sock->sk_cgroup")
Reported-by: Cameron Berkenpas <cam@neo-zeon.de>
Reported-by: Peter Geis <pgwipeout@gmail.com>
Reported-by: Lu Fengqi <lufq.fnst@cn.fujitsu.com>
Reported-by: Daniël Sonck <dsonck92@gmail.com>
Reported-by: Zhang Qiang <qiang.zhang@windriver.com>
Tested-by: Cameron Berkenpas <cam@neo-zeon.de>
Tested-by: Peter Geis <pgwipeout@gmail.com>
Tested-by: Thomas Lamprecht <t.lamprecht@proxmox.com>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Zefan Li <lizefan@huawei.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Roman Gushchin <guro@fb.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
There is exactly one argument so there is nothing to split. All
split_argv does now is cause confusion and avoid the need for a cast
when passing a "const char *" string to call_usermodehelper_setup.
So avoid confusion and the possibility of an odd driver name causing
problems by just using a fixed argv array with a cast in the call to
call_usermodehelper_setup.
v1: https://lkml.kernel.org/r/87sged3a9n.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-16-ebiederm@xmission.com
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Create an independent helper thread_group_exited which returns true
when all threads have passed exit_notify in do_exit. AKA all of the
threads are at least zombies and might be dead or completely gone.
Create this helper by taking the logic out of pidfd_poll where it is
already tested, and adding a READ_ONCE on the read of
task->exit_state.
I will be changing the user mode driver code to use this same logic
to know when a user mode driver needs to be restarted.
Place the new helper thread_group_exited in kernel/exit.c and
EXPORT it so it can be used by modules.
Link: https://lkml.kernel.org/r/20200702164140.4468-13-ebiederm@xmission.com
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
-----BEGIN PGP SIGNATURE-----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=p6ry
-----END PGP SIGNATURE-----
Merge tag 'core-urgent-2020-07-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull rcu fixlet from Thomas Gleixner:
"A single fix for a printk format warning in RCU"
* tag 'core-urgent-2020-07-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
rcuperf: Fix printk format warning
Daniel Borkmann says:
====================
pull-request: bpf-next 2020-07-04
The following pull-request contains BPF updates for your *net-next* tree.
We've added 73 non-merge commits during the last 17 day(s) which contain
a total of 106 files changed, 5233 insertions(+), 1283 deletions(-).
The main changes are:
1) bpftool ability to show PIDs of processes having open file descriptors
for BPF map/program/link/BTF objects, relying on BPF iterator progs
to extract this info efficiently, from Andrii Nakryiko.
2) Addition of BPF iterator progs for dumping TCP and UDP sockets to
seq_files, from Yonghong Song.
3) Support access to BPF map fields in struct bpf_map from programs
through BTF struct access, from Andrey Ignatov.
4) Add a bpf_get_task_stack() helper to be able to dump /proc/*/stack
via seq_file from BPF iterator progs, from Song Liu.
5) Make SO_KEEPALIVE and related options available to bpf_setsockopt()
helper, from Dmitry Yakunin.
6) Optimize BPF sk_storage selection of its caching index, from Martin
KaFai Lau.
7) Removal of redundant synchronize_rcu()s from BPF map destruction which
has been a historic leftover, from Alexei Starovoitov.
8) Several improvements to test_progs to make it easier to create a shell
loop that invokes each test individually which is useful for some CIs,
from Jesper Dangaard Brouer.
9) Fix bpftool prog dump segfault when compiled without skeleton code on
older clang versions, from John Fastabend.
10) Bunch of cleanups and minor improvements, from various others.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
Now that HAVE_COPY_THREAD_TLS has been removed, rename copy_thread_tls()
back simply copy_thread(). It's a simpler name, and doesn't imply that only
tls is copied here. This finishes an outstanding chunk of internal process
creation work since we've added clone3().
Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>A
Acked-by: Stafford Horne <shorne@gmail.com>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>A
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
All architectures support copy_thread_tls() now, so remove the legacy
copy_thread() function and the HAVE_COPY_THREAD_TLS config option. Everyone
uses the same process creation calling convention based on
copy_thread_tls() and struct kernel_clone_args. This will make it easier to
maintain the core process creation code under kernel/, simplifies the
callpaths and makes the identical for all architectures.
Cc: linux-arch@vger.kernel.org
Acked-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Acked-by: Greentime Hu <green.hu@gmail.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Now that all architectures have been switched to use _do_fork() and the new
struct kernel_clone_args calling convention we can remove the legacy
do_fork() helper completely. The calling convention used to be brittle and
do_fork() didn't buy us anything. The only calling convention accepted
should be based on struct kernel_clone_args going forward. It's cleaner and
uniform.
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: "Matthew Wilcox (Oracle)" <willy@infradead.org>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Signed-off-by: Christian Brauner <christian.brauner@ubuntu.com>
Use struct pid instead of user space pid values that are prone to wrap
araound.
In addition track the entire thread group instead of just the first
thread that is started by exec. There are no multi-threaded user mode
drivers today but there is nothing preclucing user drivers from being
multi-threaded, so it is just a good idea to track the entire process.
Take a reference count on the tgid's in question to make it possible
to remove exit_umh in a future change.
As a struct pid is available directly use kill_pid_info.
The prior process signalling code was iffy in using a userspace pid
known to be in the initial pid namespace and then looking up it's task
in whatever the current pid namespace is. It worked only because
kernel threads always run in the initial pid namespace.
As the tgid is now refcounted verify the tgid is NULL at the start of
fork_usermode_driver to avoid the possibility of silent pid leaks.
v1: https://lkml.kernel.org/r/87mu4qdlv2.fsf_-_@x220.int.ebiederm.org
v2: https://lkml.kernel.org/r/a70l4oy8.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-12-ebiederm@xmission.com
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
Instead of loading a binary blob into a temporary file with
shmem_kernel_file_setup load a binary blob into a temporary tmpfs
filesystem. This means that the blob can be stored in an init section
and discared, and it means the binary blob will have a filename so can
be executed normally.
The only tricky thing about this code is that in the helper function
blob_to_mnt __fput_sync is used. That is because a file can not be
executed if it is still open for write, and the ordinary delayed close
for kernel threads does not happen soon enough, which causes the
following exec to fail. The function umd_load_blob is not called with
any locks so this should be safe.
Executing the blob normally winds up correcting several problems with
the user mode driver code discovered by Tetsuo Handa[1]. By passing
an ordinary filename into the exec, it is no longer necessary to
figure out how to turn a O_RDWR file descriptor into a properly
referende counted O_EXEC file descriptor that forbids all writes. For
path based LSMs there are no new special cases.
[1] https://lore.kernel.org/linux-fsdevel/2a8775b4-1dd5-9d5c-aa42-9872445e0942@i-love.sakura.ne.jp/
v1: https://lkml.kernel.org/r/87d05mf0j9.fsf_-_@x220.int.ebiederm.org
v2: https://lkml.kernel.org/r/87wo3p4p35.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-8-ebiederm@xmission.com
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
I am separating the code specific to user mode drivers from the code
for ordinary user space helpers. Move setting of PF_UMH from
call_usermodehelper_exec_async which is core user mode helper code
into umh_pipe_setup which is user mode driver code.
The code is equally as easy to write in one location as the other and
the movement minimizes the impact of the user mode driver code on the
core of the user mode helper code.
Setting PF_UMH unconditionally is harmless as an action will only
happen if it is paired with an entry on umh_list.
v1: https://lkml.kernel.org/r/87bll6gf8t.fsf_-_@x220.int.ebiederm.org
v2: https://lkml.kernel.org/r/87zh8l63xs.fsf_-_@x220.int.ebiederm.org
Link: https://lkml.kernel.org/r/20200702164140.4468-2-ebiederm@xmission.com
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Acked-by: Alexei Starovoitov <ast@kernel.org>
Tested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
That was put in place for sparc64, and blackfin also used it for some time;
sparc64 no longer uses those, and blackfin is dead.
As there are no more users, remove preflow handlers.
Signed-off-by: Valentin Schneider <valentin.schneider@arm.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lkml.kernel.org/r/20200703155645.29703-3-valentin.schneider@arm.com
Fix the recently added new __vmalloc_node_range callers to pass the
correct values as the owner for display in /proc/vmallocinfo.
Fixes: 800e26b813 ("x86/hyperv: allocate the hypercall page with only read and execute bits")
Fixes: 10d5e97c1b ("arm64: use PAGE_KERNEL_ROX directly in alloc_insn_page")
Fixes: 7a0e27b2a0 ("mm: remove vmalloc_exec")
Reported-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200627075649.2455097-1-hch@lst.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
-----BEGIN PGP SIGNATURE-----
iHUEABYKAB0WIQRAhzRXHqcMeLMyaSiRxhvAZXjcogUCXv20ggAKCRCRxhvAZXjc
osYAAQD4Lp5ORPJv5jtYScxRM1RiUh8hp2MBle+4iYCAQX/UowD/QtMPtiLWaMIw
6bMMBAj1gVBmlIOmu7DhBs8hVtKugQY=
=kNpi
-----END PGP SIGNATURE-----
Merge tag 'for-linus-2020-07-02' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux
Pull data race annotation from Christian Brauner:
"This contains an annotation patch for a data race in copy_process()
reported by KCSAN when reading and writing nr_threads.
The data race is intentional and benign. This is obvious from the
comment above the relevant code and based on general consensus when
discussing this issue. So simply using data_race() to annotate this as
an intentional race seems the best option"
* tag 'for-linus-2020-07-02' of git://git.kernel.org/pub/scm/linux/kernel/git/brauner/linux:
fork: annotate data race in copy_process()
Without CONFIG_STACKTRACE stack_trace_save_tsk() is not defined. Let
get_callchain_entry_for_task() to always return NULL in such cases.
Fixes: fa28dcb82a ("bpf: Introduce helper bpf_get_task_stack()")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200703024537.79971-1-songliubraving@fb.com
-----BEGIN PGP SIGNATURE-----
iQJEBAABCAAuFiEEwPw5LcreJtl1+l5K99NY+ylx4KYFAl79YU0QHGF4Ym9lQGtl
cm5lbC5kawAKCRD301j7KXHgplHKD/9rgv0c1I7dCh6MgQKxT+2z/eZcaPO3PekW
sbn8yC8RiSIL85Av1zEfC1wAp+Mp21QlFKXFiZ6BJj5bdDbbshLk0WdbnxvuM+9I
gyngTI/+em5D/WCcetAkPjnMTDq0m4l0UXd91fyNAeErmYZbvhL5dXihZsBJ3T9c
Bprn4RzWwrUsUwGn8qIEZhx2UovMrzXJHGFxWXh/81YHkh7Y4mjvATKxtECIliW/
+QQJDU7Tf3gZw+ETPIDOEB9Hl9c9W+9fcWWzmrXzViUyy54IMbF4qyJpWcGaRh6c
sO3apymwu7wwAUbQcE8IWr3ZLZDtw68AgUdZ5b/T0c2fEwqsI/UDMhBbELiuqcT0
MAoQdUSNNqZTti0PX5vg5CQlCFzjnl2uIwHF6LVSbrqgyqxiC3Qrus/FYSaf3x9h
bAmNgWC9DeKp/wtEKMuBXaOm7RjrEutD5hjJYfVK/AkvKTZyZDx3vZ9FRH8WtrII
7KhUI3DPSZCeWlcpDtK+0fEqtqTw6OtCQ8U5vKSnJjoRSXLUtuk6IYbp/tqNxwe/
0d+U6R+w513jVlXARUP48mV7tzpESp2MLP6Nd2Is/OD5tePWzQEZinpKzsFP4djH
d2PT5FFGPCw9yBk03sI1Je/CFqVYwCGqav6h8dKKVBanMjoEdL4U1PMhI48Zua+9
M8pqRHoeDA==
=4lvI
-----END PGP SIGNATURE-----
Merge tag 'io_uring-5.8-2020-07-01' of git://git.kernel.dk/linux-block
Pull io_uring fixes from Jens Axboe:
"One fix in here, for a regression in 5.7 where a task is waiting in
the kernel for a condition, but that condition won't become true until
task_work is run. And the task_work can't be run exactly because the
task is waiting in the kernel, so we'll never make any progress.
One example of that is registering an eventfd and queueing io_uring
work, and then the task goes and waits in eventfd read with the
expectation that it'll get woken (and read an event) when the io_uring
request completes. The io_uring request is finished through task_work,
which won't get run while the task is looping in eventfd read"
* tag 'io_uring-5.8-2020-07-01' of git://git.kernel.dk/linux-block:
io_uring: use signal based task_work running
task_work: teach task_work_add() to do signal_wake_up()
Right now user-space tools like 'makedumpfile' and 'crash' need to rely
on a best-guess method of determining value of 'MAX_PHYSMEM_BITS'
supported by underlying kernel.
This value is used in user-space code to calculate the bit-space
required to store a section for SPARESMEM (similar to the existing
calculation method used in the kernel implementation):
#define SECTIONS_SHIFT (MAX_PHYSMEM_BITS - SECTION_SIZE_BITS)
Now, regressions have been reported in user-space utilities
like 'makedumpfile' and 'crash' on arm64, with the recently added
kernel support for 52-bit physical address space, as there is
no clear method of determining this value in user-space
(other than reading kernel CONFIG flags).
As per suggestion from makedumpfile maintainer (Kazu), it makes more
sense to append 'MAX_PHYSMEM_BITS' to vmcoreinfo in the core code itself
rather than in arch-specific code, so that the user-space code for other
archs can also benefit from this addition to the vmcoreinfo and use it
as a standard way of determining 'SECTIONS_SHIFT' value in user-land.
A reference 'makedumpfile' implementation which reads the
'MAX_PHYSMEM_BITS' value from vmcoreinfo in a arch-independent fashion
is available here:
While at it also update vmcoreinfo documentation for 'MAX_PHYSMEM_BITS'
variable being added to vmcoreinfo.
'MAX_PHYSMEM_BITS' defines the maximum supported physical address
space memory.
Signed-off-by: Bhupesh Sharma <bhsharma@redhat.com>
Tested-by: John Donnelly <john.p.donnelly@oracle.com>
Acked-by: Dave Young <dyoung@redhat.com>
Cc: Boris Petkov <bp@alien8.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: James Morse <james.morse@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Dave Anderson <anderson@redhat.com>
Cc: Kazuhito Hagio <k-hagio@ab.jp.nec.com>
Cc: x86@kernel.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: kexec@lists.infradead.org
Link: https://lore.kernel.org/r/1589395957-24628-2-git-send-email-bhsharma@redhat.com
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Currently, most CPUFreq governors are registered at the core_initcall
time when the given governor is the default one, and the module_init
time otherwise.
In preparation for letting users specify the default governor on the
kernel command line, change all of them to be registered at the
core_initcall unconditionally, as it is already the case for the
schedutil and performance governors. This will allow us to assume
that builtin governors have been registered before the built-in
CPUFreq drivers probe.
And since all governors have similar init/exit patterns now, introduce
two new macros, cpufreq_governor_{init,exit}(), to factorize the code.
Acked-by: Viresh Kumar <viresh.kumar@linaro.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
[ rjw: Changelog ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
After tweaking the ring buffer to be a bit faster, a warning is triggering
on one of my machines, and causing my tests to fail. This warning is caused
when the delta (current time stamp minus previous time stamp), is larger
than the max time held by the ring buffer (59 bits).
If the clock were to go backwards slightly, this would then easily trigger
this warning. The machine that it triggered on, the clock did go backwards
by around 450 nanoseconds, and this happened after a recalibration of the
TSC clock. Now that the ring buffer is faster, it detects this, and the
delta that is used larger than the max, the warning is triggered and my test
fails.
To handle the clock going backwards, look at the saved before and after time
stamps. If they are the same, it means that the current event did not
interrupt another event, and that those timestamp are of a previous event
that was recorded. If the max delta is triggered, look at those time stamps,
make sure they are the same, then use them to compare with the current
timestamp. If the current timestamp is less than the before/after time
stamps, then that means the clock being used went backward.
Print out a message that this has happened, but do not warn about it (and
only print the message once).
Still do the warning if the delta is indeed larger than what can be used.
Also remove the unneeded KERN_WARNING from the WARN_ONCE() print.
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
After doing some benchmarks and examining the code, I found that the ring
buffer clock calls were quite expensive, and noticed that it uses
retpolines. This is because the ring buffer clock is programmable, and can
be set. But in most cases it simply uses the fastest ns unit clock which is
the trace_clock_local(). For RETPOLINE builds, checking if the ring buffer
clock is set to trace_clock_local() and then calling it directly has brought
the time of an event on my i7 box from an average of 93 nanoseconds an event
down to 83 nanoseconds an event, and the minimum time from 81 nanoseconds to
68 nanoseconds!
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Make a helper function rb_add_timestamp() that moves the adding of the
extended time stamps into its own function. Also, remove the noinline and
inline for the functions it calls, as recent benchmarks appear they do not
make a difference (just let gcc decide).
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reorganize a little the logic to handle adding the absolute time stamp,
extended and forced time stamps, in such a way to remove a branch or two.
This is just a micro optimization.
Also add before and after time stamps to the rb_event_info structure to
display those values in the rb_check_timestamps() code, if something were to
go wrong.
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
This makes it easy to dump stack trace in text.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630062846.664389-4-songliubraving@fb.com
Introduce helper bpf_get_task_stack(), which dumps stack trace of given
task. This is different to bpf_get_stack(), which gets stack track of
current task. One potential use case of bpf_get_task_stack() is to call
it from bpf_iter__task and dump all /proc/<pid>/stack to a seq_file.
bpf_get_task_stack() uses stack_trace_save_tsk() instead of
get_perf_callchain() for kernel stack. The benefit of this choice is that
stack_trace_save_tsk() doesn't require changes in arch/. The downside of
using stack_trace_save_tsk() is that stack_trace_save_tsk() dumps the
stack trace to unsigned long array. For 32-bit systems, we need to
translate it to u64 array.
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630062846.664389-3-songliubraving@fb.com
Sanitize and expose get/put_callchain_entry(). This would be used by bpf
stack map.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630062846.664389-2-songliubraving@fb.com
bpf_free_used_maps() or close(map_fd) will trigger map_free callback.
bpf_free_used_maps() is called after bpf prog is no longer executing:
bpf_prog_put->call_rcu->bpf_prog_free->bpf_free_used_maps.
Hence there is no need to call synchronize_rcu() to protect map elements.
Note that hash_of_maps and array_of_maps update/delete inner maps via
sys_bpf() that calls maybe_wait_bpf_programs() and synchronize_rcu().
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Link: https://lore.kernel.org/bpf/20200630043343.53195-2-alexei.starovoitov@gmail.com
The unicore32 port do not seem maintained for a long time now, there is no
upstream toolchain that can create unicore32 binaries and all the links to
prebuilt toolchains for unicore32 are dead. Even compilers that were
available are not supported by the kernel anymore.
Guenter Roeck says:
I have stopped building unicore32 images since v4.19 since there is no
available compiler that is still supported by the kernel. I am surprised
that support for it has not been removed from the kernel.
Remove unicore32 port.
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Guenter Roeck <linux@roeck-us.net>
Daniel Borkmann says:
====================
pull-request: bpf 2020-06-30
The following pull-request contains BPF updates for your *net* tree.
We've added 28 non-merge commits during the last 9 day(s) which contain
a total of 35 files changed, 486 insertions(+), 232 deletions(-).
The main changes are:
1) Fix an incorrect verifier branch elimination for PTR_TO_BTF_ID pointer
types, from Yonghong Song.
2) Fix UAPI for sockmap and flow_dissector progs that were ignoring various
arguments passed to BPF_PROG_{ATTACH,DETACH}, from Lorenz Bauer & Jakub Sitnicki.
3) Fix broken AF_XDP DMA hacks that are poking into dma-direct and swiotlb
internals and integrate it properly into DMA core, from Christoph Hellwig.
4) Fix RCU splat from recent changes to avoid skipping ingress policy when
kTLS is enabled, from John Fastabend.
5) Fix BPF ringbuf map to enforce size to be the power of 2 in order for its
position masking to work, from Andrii Nakryiko.
6) Fix regression from CAP_BPF work to re-allow CAP_SYS_ADMIN for loading
of network programs, from Maciej Żenczykowski.
7) Fix libbpf section name prefix for devmap progs, from Jesper Dangaard Brouer.
8) Fix formatting in UAPI documentation for BPF helpers, from Quentin Monnet.
====================
Signed-off-by: David S. Miller <davem@davemloft.net>
It is the uncommon case where an event crosses a sub buffer boundary (page)
mark that check at the end of reserving an event as unlikely.
Suggested-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
On a 144 thread system, `perf ftrace` takes about 20 seconds to start
up, due to calling synchronize_rcu() for each CPU.
cat /proc/108560/stack
0xc0003e7eb336f470
__switch_to+0x2e0/0x480
__wait_rcu_gp+0x20c/0x220
synchronize_rcu+0x9c/0xc0
ring_buffer_reset_cpu+0x88/0x2e0
tracing_reset_online_cpus+0x84/0xe0
tracing_open+0x1d4/0x1f0
On a system with 10x more threads, it starts to become an annoyance.
Batch these up so we disable all the per-cpu buffers first, then
synchronize_rcu() once, then reset each of the buffers. This brings
the time down to about 0.5s.
Link: https://lkml.kernel.org/r/20200625053403.2386972-1-npiggin@gmail.com
Tested-by: Anton Blanchard <anton@ozlabs.org>
Acked-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
After a discussion with the new time algorithm to have nested events still
have proper time keeping but required using local64_t atomic operations.
Mathieu was concerned about the performance this would have on 32 bit
machines, as in most cases, atomic 64 bit operations on them can be
expensive.
As the ring buffer's timing needs do not require full features of local64_t,
a wrapper is made to implement a new rb_time_t operation that uses two longs
on 32 bit machines but still uses the local64_t operations on 64 bit
machines. There's a switch that can be made in the file to force 64 bit to
use the 32 bit version just for testing purposes.
All reads do not need to succeed if a read happened while the stamp being
read is in the process of being updated. The requirement is that all reads
must succed that were done by an interrupting event (where this event was
interrupted by another event that did the write). Or if the event itself did
the write first. That is: rb_time_set(t, x) followed by rb_time_read(t) will
always succeed (even if it gets interrupted by another event that writes to
t. The result of the read will be either the previous set, or a set
performed by an interrupting event.
If the read is done by an event that interrupted another event that was in
the process of setting the time stamp, and no other event came along to
write to that time stamp, it will fail and the rb_time_read() will return
that it failed (the value to read will be undefined).
A set will always write to the time stamp and return with a valid time
stamp, such that any read after it will be valid.
A cmpxchg may fail if it interrupted an event that was in the process of
updating the time stamp just like the reads do. Other than that, it will act
like a normal cmpxchg.
The way this works is that the rb_time_t is made of of three fields. A cnt,
that gets updated atomically everyting a modification is made. A top that
represents the most significant 30 bits of the time, and a bottom to
represent the least significant 30 bits of the time. Notice, that the time
values is only 60 bits long (where the ring buffer only uses 59 bits, which
gives us 18 years of nanoseconds!).
The top two bits of both the top and bottom is a 2 bit counter that gets set
by the value of the least two significant bits of the cnt. A read of the top
and the bottom where both the top and bottom have the same most significant
top 2 bits, are considered a match and a valid 60 bit number can be created
from it. If they do not match, then the number is considered invalid, and
this must only happen if an event interrupted another event in the midst of
updating the time stamp.
This is only used for 32 bits machines as 64 bit machines can get better
performance out of the local64_t. This has been tested heavily by forcing 64
bit to use this logic.
Link: https://lore.kernel.org/r/20200625225345.18cf5881@oasis.local.home
Link: http://lkml.kernel.org/r/20200629025259.309232719@goodmis.org
Inspired-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Wenbo reported an issue in [1] where a checking of null
pointer is evaluated as always false. In this particular
case, the program type is tp_btf and the pointer to
compare is a PTR_TO_BTF_ID.
The current verifier considers PTR_TO_BTF_ID always
reprents a non-null pointer, hence all PTR_TO_BTF_ID compares
to 0 will be evaluated as always not-equal, which resulted
in the branch elimination.
For example,
struct bpf_fentry_test_t {
struct bpf_fentry_test_t *a;
};
int BPF_PROG(test7, struct bpf_fentry_test_t *arg)
{
if (arg == 0)
test7_result = 1;
return 0;
}
int BPF_PROG(test8, struct bpf_fentry_test_t *arg)
{
if (arg->a == 0)
test8_result = 1;
return 0;
}
In above bpf programs, both branch arg == 0 and arg->a == 0
are removed. This may not be what developer expected.
The bug is introduced by Commit cac616db39 ("bpf: Verifier
track null pointer branch_taken with JNE and JEQ"),
where PTR_TO_BTF_ID is considered to be non-null when evaluting
pointer vs. scalar comparison. This may be added
considering we have PTR_TO_BTF_ID_OR_NULL in the verifier
as well.
PTR_TO_BTF_ID_OR_NULL is added to explicitly requires
a non-NULL testing in selective cases. The current generic
pointer tracing framework in verifier always
assigns PTR_TO_BTF_ID so users does not need to
check NULL pointer at every pointer level like a->b->c->d.
We may not want to assign every PTR_TO_BTF_ID as
PTR_TO_BTF_ID_OR_NULL as this will require a null test
before pointer dereference which may cause inconvenience
for developers. But we could avoid branch elimination
to preserve original code intention.
This patch simply removed PTR_TO_BTD_ID from reg_type_not_null()
in verifier, which prevented the above branches from being eliminated.
[1]: https://lore.kernel.org/bpf/79dbb7c0-449d-83eb-5f4f-7af0cc269168@fb.com/T/
Fixes: cac616db39 ("bpf: Verifier track null pointer branch_taken with JNE and JEQ")
Reported-by: Wenbo Zhang <ethercflow@gmail.com>
Signed-off-by: Yonghong Song <yhs@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Link: https://lore.kernel.org/bpf/20200630171240.2523722-1-yhs@fb.com
Instead of calling out the absolute test for each time to check if the
ring buffer wants absolute time stamps for all its recording, incorporate it
with the add_timestamp field and turn it into flags for faster processing
between wanting a absolute tag and needing to force one.
Link: http://lkml.kernel.org/r/20200629025259.154892368@goodmis.org
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Up until now, if an event is interrupted while it is recorded by an
interrupt, and that interrupt records events, the time of those events will
all be the same. This is because events only record the delta of the time
since the previous event (or beginning of a page), and to handle updating
the time keeping for that of nested events is extremely racy. After years of
thinking about this and several failed attempts, I finally have a solution
to solve this puzzle.
The problem is that you need to atomically calculate the delta and then
update the time stamp you made the delta from, as well as then record it
into the buffer, all this while at any time an interrupt can come in and
do the same thing. This is easy to solve with heavy weight atomics, but that
would be detrimental to the performance of the ring buffer. The current
state of affairs sacrificed the time deltas for nested events for
performance.
The reason for previous failed attempts at solving this puzzle was because I
was trying to completely avoid slow atomic operations like cmpxchg. I final
came to the conclusion to always avoid cmpxchg is not possible, which is why
those previous attempts always failed. But it is possible to pick one path
(the most common case) and avoid cmpxchg in that path, which is the "fast
path". The most common case is that an event will not be interrupted and
have other events added into it. An event can detect if it has
interrupted another event, and for these cases we can make it the slow
path and use the heavy operations like cmpxchg.
One more player was added to the game that made this possible, and that is
the "absolute timestamp" (by Tom Zanussi) that allows us to inject a full 59
bit time stamp. (Of course this breaks if a machine is running for more than
18 years without a reboot!).
There's barrier() placements around for being paranoid, even when they
are not needed because of other atomic functions near by. But those
should not hurt, as if they are not needed, they basically become a nop.
Note, this also makes the race window much smaller, which means there
are less slow paths to slow down the performance.
The basic idea is that there's two main paths taken.
1) Not being interrupted between time stamps and reserving buffer space.
In this case, the time stamps taken are true to the location in the
buffer.
2) Was interrupted by another path between taking time stamps and reserving
buffer space.
The objective is to know what the delta is from the last reserved location
in the buffer.
As it is possible to detect if an event is interrupting another event before
reserving data, space is added to the length to be reserved to inject a full
time stamp along with the event being reserved.
When an event is not interrupted, the write stamp is always the time of the
last event written to the buffer.
In path 1, there's two sub paths we care about:
a) The event did not interrupt another event.
b) The event interrupted another event.
In case a, as the write stamp was read and known to be correct, the delta
between the current time stamp and the write stamp is the delta between the
current event and the previously recorded event.
In case b, extra space was reserved to just put the full time stamp into the
buffer. Which is done, as stated, in this path the time stamp taken is known
to match the location in the buffer.
In path 2, there's also two sub paths we care about:
a) The event was not interrupted by another event since it reserved space
on the buffer and re-reading the write stamp.
b) The event was interrupted by another event.
In case a, the write stamp is that of the last event that interrupted this
event between taking the time stamps and reserving. As no event came in
after re-reading the write stamp, that event is known to be the time of the
event directly before this event and the delta can be the new time stamp and
the write stamp.
In case b, one or more events came in between reserving the event and
re-reading he write stamp. Since this event's buffer reservation is between
other events at this path, there's no way to know what the delta is. But
because an event interrupted this event after it started, its fine to just
give a zero delta, and take the same time stamp as the events that happened
within the event being recorded.
Here's the implementation of the design of this solution:
All this is per cpu, and only needs to worry about nested events (not
parallel events).
The players:
write_tail: The index in the buffer where new events can be written to.
It is incremented via local_add() to reserve space for a new event.
before_stamp: A time stamp set by all events before reserving space.
write_stamp: A time stamp updated by events after it has successfully
reserved space.
/* Save the current position of write */
[A] w = local_read(write_tail);
barrier();
/* Read both before and write stamps before touching anything */
before = local_read(before_stamp);
after = local_read(write_stamp);
barrier();
/*
* If before and after are the same, then this event is not
* interrupting a time update. If it is, then reserve space for adding
* a full time stamp (this can turn into a time extend which is
* just an extended time delta but fill up the extra space).
*/
if (after != before)
abs = true;
ts = clock();
/* Now update the before_stamp (everyone does this!) */
[B] local_set(before_stamp, ts);
/* Now reserve space on the buffer */
[C] write = local_add_return(len, write_tail);
/* Set tail to be were this event's data is */
tail = write - len;
if (w == tail) {
/* Nothing interrupted this between A and C */
[D] local_set(write_stamp, ts);
barrier();
[E] save_before = local_read(before_stamp);
if (!abs) {
/* This did not interrupt a time update */
delta = ts - after;
} else {
delta = ts; /* The full time stamp will be in use */
}
if (ts != save_before) {
/* slow path - Was interrupted between C and E */
/* The update to write_stamp could have overwritten the update to
* it by the interrupting event, but before and after should be
* the same for all completed top events */
after = local_read(write_stamp);
if (save_before > after)
local_cmpxchg(write_stamp, after, save_before);
}
} else {
/* slow path - Interrupted between A and C */
after = local_read(write_stamp);
temp_ts = clock();
barrier();
[F] if (write == local_read(write_tail) && after < temp_ts) {
/* This was not interrupted since C and F
* The last write_stamp is still valid for the previous event
* in the buffer. */
delta = temp_ts - after;
/* OK to keep this new time stamp */
ts = temp_ts;
} else {
/* Interrupted between C and F
* Well, there's no use to try to know what the time stamp
* is for the previous event. Just set delta to zero and
* be the same time as that event that interrupted us before
* the reservation of the buffer. */
delta = 0;
}
/* No need to use full timestamps here */
abs = 0;
}
Link: https://lkml.kernel.org/r/20200625094454.732790f7@oasis.local.home
Link: https://lore.kernel.org/r/20200627010041.517736087@goodmis.org
Link: http://lkml.kernel.org/r/20200629025258.957440797@goodmis.org
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
If a process has the trace_pipe open on a trace_array, the current tracer
for that trace array should not be changed. This was original enforced by a
global lock, but when instances were introduced, it was moved to the
current_trace. But this structure is shared by all instances, and a
trace_pipe is for a single instance. There's no reason that a process that
has trace_pipe open on one instance should prevent another instance from
changing its current tracer. Move the reference counter to the trace_array
instead.
This is marked as "Fixes" but is more of a clean up than a true fix.
Backport if you want, but its not critical.
Fixes: cf6ab6d914 ("tracing: Add ref count to tracer for when they are being read by pipe")
Signed-off-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
So that the target task will exit the wait_event_interruptible-like
loop and call task_work_run() asap.
The patch turns "bool notify" into 0,TWA_RESUME,TWA_SIGNAL enum, the
new TWA_SIGNAL flag implies signal_wake_up(). However, it needs to
avoid the race with recalc_sigpending(), so the patch also adds the
new JOBCTL_TASK_WORK bit included in JOBCTL_PENDING_MASK.
TODO: once this patch is merged we need to change all current users
of task_work_add(notify = true) to use TWA_RESUME.
Cc: stable@vger.kernel.org # v5.7
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Iterating over BPF links attached to network namespace in pre_exit hook is
not safe, even if there is just one. Once link gets auto-detached, that is
its back-pointer to net object is set to NULL, the link can be released and
freed without waiting on netns_bpf_mutex, effectively causing the list
element we are operating on to be freed.
This leads to use-after-free when trying to access the next element on the
list, as reported by KASAN. Bug can be triggered by destroying a network
namespace, while also releasing a link attached to this network namespace.
| ==================================================================
| BUG: KASAN: use-after-free in netns_bpf_pernet_pre_exit+0xd9/0x130
| Read of size 8 at addr ffff888119e0d778 by task kworker/u8:2/177
|
| CPU: 3 PID: 177 Comm: kworker/u8:2 Not tainted 5.8.0-rc1-00197-ga0c04c9d1008-dirty #776
| Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ?-20190727_073836-buildvm-ppc64le-16.ppc.fedoraproject.org-3.fc31 04/01/2014
| Workqueue: netns cleanup_net
| Call Trace:
| dump_stack+0x9e/0xe0
| print_address_description.constprop.0+0x3a/0x60
| ? netns_bpf_pernet_pre_exit+0xd9/0x130
| kasan_report.cold+0x1f/0x40
| ? netns_bpf_pernet_pre_exit+0xd9/0x130
| netns_bpf_pernet_pre_exit+0xd9/0x130
| cleanup_net+0x30b/0x5b0
| ? unregister_pernet_device+0x50/0x50
| ? rcu_read_lock_bh_held+0xb0/0xb0
| ? _raw_spin_unlock_irq+0x24/0x50
| process_one_work+0x4d1/0xa10
| ? lock_release+0x3e0/0x3e0
| ? pwq_dec_nr_in_flight+0x110/0x110
| ? rwlock_bug.part.0+0x60/0x60
| worker_thread+0x7a/0x5c0
| ? process_one_work+0xa10/0xa10
| kthread+0x1e3/0x240
| ? kthread_create_on_node+0xd0/0xd0
| ret_from_fork+0x1f/0x30
|
| Allocated by task 280:
| save_stack+0x1b/0x40
| __kasan_kmalloc.constprop.0+0xc2/0xd0
| netns_bpf_link_create+0xfe/0x650
| __do_sys_bpf+0x153a/0x2a50
| do_syscall_64+0x59/0x300
| entry_SYSCALL_64_after_hwframe+0x44/0xa9
|
| Freed by task 198:
| save_stack+0x1b/0x40
| __kasan_slab_free+0x12f/0x180
| kfree+0xed/0x350
| process_one_work+0x4d1/0xa10
| worker_thread+0x7a/0x5c0
| kthread+0x1e3/0x240
| ret_from_fork+0x1f/0x30
|
| The buggy address belongs to the object at ffff888119e0d700
| which belongs to the cache kmalloc-192 of size 192
| The buggy address is located 120 bytes inside of
| 192-byte region [ffff888119e0d700, ffff888119e0d7c0)
| The buggy address belongs to the page:
| page:ffffea0004678340 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0
| flags: 0x2fffe0000000200(slab)
| raw: 02fffe0000000200 ffffea00045ba8c0 0000000600000006 ffff88811a80ea80
| raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
| page dumped because: kasan: bad access detected
|
| Memory state around the buggy address:
| ffff888119e0d600: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ffff888119e0d680: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
| >ffff888119e0d700: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ^
| ffff888119e0d780: fb fb fb fb fb fb fb fb fc fc fc fc fc fc fc fc
| ffff888119e0d800: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
| ==================================================================
Remove the "fast-path" for releasing a link that got auto-detached by a
dying network namespace to fix it. This way as long as link is on the list
and netns_bpf mutex is held, we have a guarantee that link memory can be
accessed.
An alternative way to fix this issue would be to safely iterate over the
list of links and ensure there is no access to link object after detaching
it. But, at the moment, optimizing synchronization overhead on link release
without a workload in mind seems like an overkill.
Fixes: ab53cad90e ("bpf, netns: Keep a list of attached bpf_link's")
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Yonghong Song <yhs@fb.com>
Link: https://lore.kernel.org/bpf/20200630164541.1329993-1-jakub@cloudflare.com
The sockmap code currently ignores the value of attach_bpf_fd when
detaching a program. This is contrary to the usual behaviour of
checking that attach_bpf_fd represents the currently attached
program.
Ensure that attach_bpf_fd is indeed the currently attached
program. It turns out that all sockmap selftests already do this,
which indicates that this is unlikely to cause breakage.
Fixes: 604326b41a ("bpf, sockmap: convert to generic sk_msg interface")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-5-lmb@cloudflare.com
Using BPF_PROG_DETACH on a flow dissector program supports neither
attach_flags nor attach_bpf_fd. Yet no value is enforced for them.
Enforce that attach_flags are zero, and require the current program
to be passed via attach_bpf_fd. This allows us to remove the check
for CAP_SYS_ADMIN, since userspace can now no longer remove
arbitrary flow dissector programs.
Fixes: b27f7bb590 ("flow_dissector: Move out netns_bpf prog callbacks")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-3-lmb@cloudflare.com
Using BPF_PROG_ATTACH on a flow dissector program supports neither
target_fd, attach_flags or replace_bpf_fd but accepts any value.
Enforce that all of them are zero. This is fine for replace_bpf_fd
since its presence is indicated by BPF_F_REPLACE. It's more
problematic for target_fd, since zero is a valid fd. Should we
want to use the flag later on we'd have to add an exception for
fd 0. The alternative is to force a value like -1. This requires
more changes to tests. There is also precedent for using 0,
since bpf_iter uses this for target_fd as well.
Fixes: b27f7bb590 ("flow_dissector: Move out netns_bpf prog callbacks")
Signed-off-by: Lorenz Bauer <lmb@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20200629095630.7933-2-lmb@cloudflare.com
To support multi-prog link-based attachments for new netns attach types, we
need to keep track of more than one bpf_link per attach type. Hence,
convert net->bpf.links into a list, that currently can be either empty or
have just one item.
Instead of reusing bpf_prog_list from bpf-cgroup, we link together
bpf_netns_link's themselves. This makes list management simpler as we don't
have to allocate, initialize, and later release list elements. We can do
this because multi-prog attachment will be available only for bpf_link, and
we don't need to build a list of programs attached directly and indirectly
via links.
No functional changes intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-4-jakub@cloudflare.com
Prepare for having multi-prog attachments for new netns attach types by
storing programs to run in a bpf_prog_array, which is well suited for
iterating over programs and running them in sequence.
After this change bpf(PROG_QUERY) may block to allocate memory in
bpf_prog_array_copy_to_user() for collected program IDs. This forces a
change in how we protect access to the attached program in the query
callback. Because bpf_prog_array_copy_to_user() can sleep, we switch from
an RCU read lock to holding a mutex that serializes updaters.
Because we allow only one BPF flow_dissector program to be attached to
netns at all times, the bpf_prog_array pointed by net->bpf.run_array is
always either detached (null) or one element long.
No functional changes intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.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/20200625141357.910330-3-jakub@cloudflare.com
Prepare for using bpf_prog_array to store attached programs by moving out
code that updates the attached program out of flow dissector.
Managing bpf_prog_array is more involved than updating a single bpf_prog
pointer. This will let us do it all from one place, bpf/net_namespace.c, in
the subsequent patch.
No functional change intended.
Signed-off-by: Jakub Sitnicki <jakub@cloudflare.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Andrii Nakryiko <andriin@fb.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20200625141357.910330-2-jakub@cloudflare.com
BPF ringbuf assumes the size to be a multiple of page size and the power of
2 value. The latter is important to avoid division while calculating position
inside the ring buffer and using (N-1) mask instead. This patch fixes omission
to enforce power-of-2 size rule.
Fixes: 457f44363a ("bpf: Implement BPF ring buffer and verifier support for it")
Signed-off-by: Andrii Nakryiko <andriin@fb.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200630061500.1804799-1-andriin@fb.com
Add a new API to check if calls to dma_sync_single_for_{device,cpu} are
required for a given DMA streaming mapping.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20200629130359.2690853-2-hch@lst.de
Fixed an inconsistent use of GFP flags in nft_obj_notify() that used
GFP_KERNEL when a GFP flag was passed in to that function. Given this
allocated memory was then used in audit_log_nfcfg() it led to an audit
of all other GFP allocations in net/netfilter/nf_tables_api.c and a
modification of audit_log_nfcfg() to accept a GFP parameter.
Reported-by: Dan Carptenter <dan.carpenter@oracle.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Signed-off-by: Paul Moore <paul@paul-moore.com>
Disable branch tracing in core KCSAN runtime if branches are being
traced (TRACE_BRANCH_PROFILING). This it to avoid its performance
impact, but also avoid recursion in case KCSAN is enabled for the branch
tracing runtime.
The latter had already been a problem for KASAN:
https://lore.kernel.org/lkml/CANpmjNOeXmD5E3O50Z3MjkiuCYaYOPyi+1rq=GZvEKwBvLR0Ug@mail.gmail.com/
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Simplify the set of compiler flags for the runtime by removing cc-option
from -fno-stack-protector, because all supported compilers support it.
This saves us one compiler invocation during build.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add a test that KCSAN nor the compiler gets confused about accesses to
jiffies on different architectures.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Remove existing special atomic rules from kcsan_is_atomic_special()
because they are no longer needed. Since we rely on the compiler
emitting instrumentation distinguishing volatile accesses, the rules
have become redundant.
Let's keep kcsan_is_atomic_special() around, so that we have an obvious
place to add special rules should the need arise in future.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Rename 'test.c' to 'selftest.c' to better reflect its purpose (Kconfig
variable and code inside already match this). This is to avoid confusion
with the test suite module in 'kcsan-test.c'.
No functional change.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The functions here should not be forward declared for explicit use
elsewhere in the kernel, as they should only be emitted by the compiler
due to sanitizer instrumentation. Add forward declarations a line above
their definition to shut up warnings in W=1 builds.
Link: https://lkml.kernel.org/r/202006060103.jSCpnV1g%lkp@intel.com
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Instead of __no_kcsan_or_inline, prefer '__no_kcsan inline' in test --
this is in case we decide to remove __no_kcsan_or_inline.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The prev->next pointer can be accessed concurrently as noticed by KCSAN:
write (marked) to 0xffff9d3370dbbe40 of 8 bytes by task 3294 on cpu 107:
osq_lock+0x25f/0x350
osq_wait_next at kernel/locking/osq_lock.c:79
(inlined by) osq_lock at kernel/locking/osq_lock.c:185
rwsem_optimistic_spin
<snip>
read to 0xffff9d3370dbbe40 of 8 bytes by task 3398 on cpu 100:
osq_lock+0x196/0x350
osq_lock at kernel/locking/osq_lock.c:157
rwsem_optimistic_spin
<snip>
Since the write only stores NULL to prev->next and the read tests if
prev->next equals to this_cpu_ptr(&osq_node). Even if the value is
shattered, the code is still working correctly. Thus, mark it as an
intentional data race using the data_race() macro.
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This adds KCSAN test focusing on behaviour of the integrated runtime.
Tests various race scenarios, and verifies the reports generated to
console. Makes use of KUnit for test organization, and the Torture
framework for test thread control.
Signed-off-by: Marco Elver <elver@google.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
struct vm_area_struct could be accessed concurrently as noticed by
KCSAN,
write to 0xffff9cf8bba08ad8 of 8 bytes by task 14263 on cpu 35:
vma_interval_tree_insert+0x101/0x150:
rb_insert_augmented_cached at include/linux/rbtree_augmented.h:58
(inlined by) vma_interval_tree_insert at mm/interval_tree.c:23
__vma_link_file+0x6e/0xe0
__vma_link_file at mm/mmap.c:629
vma_link+0xa2/0x120
mmap_region+0x753/0xb90
do_mmap+0x45c/0x710
vm_mmap_pgoff+0xc0/0x130
ksys_mmap_pgoff+0x1d1/0x300
__x64_sys_mmap+0x33/0x40
do_syscall_64+0x91/0xc44
entry_SYSCALL_64_after_hwframe+0x49/0xbe
read to 0xffff9cf8bba08a80 of 200 bytes by task 14262 on cpu 122:
vm_area_dup+0x6a/0xe0
vm_area_dup at kernel/fork.c:362
__split_vma+0x72/0x2a0
__split_vma at mm/mmap.c:2661
split_vma+0x5a/0x80
mprotect_fixup+0x368/0x3f0
do_mprotect_pkey+0x263/0x420
__x64_sys_mprotect+0x51/0x70
do_syscall_64+0x91/0xc44
entry_SYSCALL_64_after_hwframe+0x49/0xbe
vm_area_dup() blindly copies all fields of original VMA to the new one.
This includes coping vm_area_struct::shared.rb which is normally
protected by i_mmap_lock. But this is fine because the read value will
be overwritten on the following __vma_link_file() under proper
protection. Thus, mark it as an intentional data race and insert a few
assertions for the fields that should not be modified concurrently.
Signed-off-by: Qian Cai <cai@lca.pw>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
If there is a large number of torture tests running concurrently,
all of which are dumping large ftrace buffers at shutdown time, the
resulting dumping can take a very long time, particularly on systems
with rotating-rust storage. This commit therefore adds a default-off
torture.ftrace_dump_at_shutdown module parameter that enables
shutdown-time ftrace-buffer dumping.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
RCU is supposed to be watching all non-idle kernel code and also all
softirq handlers. This commit adds some teeth to this statement by
adding a WARN_ON_ONCE().
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Coccinelle reports a warning
WARNING: Assignment of 0/1 to bool variable
The root cause is that the variable lastphase is a bool, but is
initialised with integer 0. This commit therefore replaces the 0 with
a false.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, the rcu_torture_current variable remains non-NULL until after
all readers have stopped. During this time, rcu_torture_stats_print()
will think that the test is still ongoing, which can result in confusing
dmesg output. This commit therefore NULLs rcu_torture_current immediately
after the rcu_torture_writer() kthread has decided to stop, thus informing
rcu_torture_stats_print() much sooner.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Several variants of Linux-kernel RCU interact with task-exit processing,
including preemptible RCU, Tasks RCU, and Tasks Trace RCU. This commit
therefore adds testing of this interaction to rcutorture by adding
rcutorture.read_exit_burst and rcutorture.read_exit_delay kernel-boot
parameters. These kernel parameters control the frequency and spacing
of special read-then-exit kthreads that are spawned.
[ paulmck: Apply feedback from Dan Carpenter's static checker. ]
[ paulmck: Reduce latency to avoid false-positive shutdown hangs. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit fixes the following coccicheck warnings:
kernel/locking/locktorture.c:689:6-10: WARNING: Assignment of 0/1 to bool variable
kernel/locking/locktorture.c:907:2-20: WARNING: Assignment of 0/1 to bool variable
kernel/locking/locktorture.c:938:3-20: WARNING: Assignment of 0/1 to bool variable
kernel/locking/locktorture.c:668:2-19: WARNING: Assignment of 0/1 to bool variable
kernel/locking/locktorture.c:674:2-19: WARNING: Assignment of 0/1 to bool variable
kernel/locking/locktorture.c:634:2-20: WARNING: Assignment of 0/1 to bool variable
kernel/locking/locktorture.c:640:2-20: WARNING: Assignment of 0/1 to bool variable
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
SRCU disables interrupts to get a stable per-CPU pointer and then
acquires the spinlock which is in the per-CPU data structure. The
release uses spin_unlock_irqrestore(). While this is correct on a non-RT
kernel, this conflicts with the RT semantics because the spinlock is
converted to a 'sleeping' spinlock. Sleeping locks can obviously not be
acquired with interrupts disabled.
Acquire the per-CPU pointer `ssp->sda' without disabling preemption and
then acquire the spinlock_t of the per-CPU data structure. The lock will
ensure that the data is consistent.
The added call to check_init_srcu_struct() is now needed because a
statically defined srcu_struct may remain uninitialized until this
point and the newly introduced locking operation requires an initialized
spinlock_t.
This change was tested for four hours with 8*SRCU-N and 8*SRCU-P without
causing any warnings.
Cc: Lai Jiangshan <jiangshanlai@gmail.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: rcu@vger.kernel.org
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit further avoids conflation of refperf with the kernel's perf
feature by renaming kernel/rcu/refperf.c to kernel/rcu/refscale.c,
and also by similarly renaming the functions and variables inside
this file. This has the side effect of changing the names of the
kernel boot parameters, so kernel-parameters.txt and ver_functions.sh
are also updated.
The rcutorture --torture type remains refperf, and this will be
addressed in a separate commit.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The old Kconfig option name is all too easy to conflate with the
unrelated "perf" feature, so this commit renames RCU_REF_PERF_TEST to
RCU_REF_SCALE_TEST.
Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The synchronize_rcu_tasks_trace() header comment incorrectly claims that
any number of things delimit RCU Tasks Trace read-side critical sections,
when in fact only rcu_read_lock_trace() and rcu_read_unlock_trace() do so.
This commit therefore fixes this comment, and, while in the area, fixes
a typo in the rcu_read_lock_trace() header comment.
Reported-by: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds testing for RCU Tasks readers to the refperf module.
This also applies to RCU Rude readers, as both flavors have empty
(as in non-existent) read-side markers.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The current units of microseconds are too coarse, so this commit
changes the units to nanoseconds. However, ndelay is used only for the
nanoseconds with udelay being used for whole microseconds. For example,
setting refperf.readdelay=1500 results in a udelay(1) followed by an
ndelay(500).
Suggested-by: Akira Yokosawa <akiyks@gmail.com>
[ paulmck: Abstracted delay per Akira feedback and move from 80 to 100 lines. ]
[ paulmck: Fix names as suggested by kbuild test robot. ]
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
A 64-bit division was introduced in refperf, breaking compilation
on all 32-bit architectures:
kernel/rcu/refperf.o: in function `main_func':
refperf.c:(.text+0x57c): undefined reference to `__aeabi_uldivmod'
Fix this by using div_u64 to mark the expensive operation.
[ paulmck: Update primitive and format per Nathan Chancellor. ]
Fixes: bd5b16d6c88d ("refperf: Allow decimal nanoseconds")
Reported-by: kbuild test robot <lkp@intel.com>
Reported-by: Valdis Klētnieks <valdis.kletnieks@vt.edu>
Acked-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
With the various measurement optimizations, 10,000 loops normally
suffices. This commit therefore reduces the refperf.loops default value
from 10,000,000 to 10,000.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds a refperf.readdelay module parameter that controls the
duration of each critical section. This parameter allows gathering data
showing how the performance differences between the various primitives
vary with critical-section length.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit moves the reader-launch wait loop from ref_perf_init()
to main_func(), removing one layer of wakeup and allowing slightly
faster system boot.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The experiment-number column is currently labeled "Threads", which is
misleading at best. This commit therefore relabels it as "Runs", and
adjusts the scripts accordingly.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit causes all the readers to start running unmeasured load
until all readers have done at least one such run (thus having warmed
up), then run the measured load, and then run unmeasured load until all
readers have completed their measured load. This approach avoids any
thread running measured load while other readers are idle.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, readers are awakened individually. On most systems, this
results in significant wakeup delay from one reader to the next, which
can result in the first and last reader having sole access to the
synchronization primitive in question. If that synchronization primitive
involves shared memory, those readers will rack up a huge number of
operations in a very short time, causing large perturbations in the
results.
This commit therefore has the readers busy-wait after being awakened,
and uses a new n_started variable to synchronize their start times.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit converts the reader_task structure's "start" field to int
in order to demote a full barrier to an smp_load_acquire() and also to
simplify the code a bit. While in the area, and to enlist the compiler's
help in ensuring that nothing was missed, the field's name was changed
to start_reader.
Also while in the area, change the main_func() store to use
smp_store_release() to further fortify against wait/wake races.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit moves a printk() out of the measurement interval, converts
a atomic_dec()/atomic_read() pair to atomic_dec_and_test(), and adds
a smp_mb__before_atomic() to avoid potential wake/wait hangs. These
changes have the added benefit of reducing the number of loops required
for amortizing loop overhead for CONFIG_PREEMPT=n RCU measurements from
1,000,000 to 10,000. This reduction in turn shortens the test, reducing
the probability of interference.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Because the reset_readers() and process_durations() functions are used
only within kernel/rcu/refperf.c, this commit makes them static.
Reported-by: kbuild test robot <lkp@intel.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, the buffer used to accumulate the thread-summary output is
fixed size, which will cause problems if someone decides to run on a large
number of PCUs. This commit therefore dynamically allocates this buffer.
[ paulmck: Fix memory allocation as suggested by KASAN. ]
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, the buffer used to accumulate the experiment-summary output
is fixed size, which will cause problems if someone decides to run
one hundred experiments. This commit therefore dynamically allocates
this buffer.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The current code uses the number of threads both to limit the number
of threads and to specify the number of experiments, but also varies
the number of threads as the experiments progress. This commit takes
a different approach by adding an refperf.nruns module parameter that
specifies the number of experiments, and furthermore uses the same
number of threads for each experiment.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit converts nreaders to a module parameter, with the default
of -1 specifying the old behavior of using 75% of the readers.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The CONFIG_PREEMPT=n rcu_read_lock()/rcu_read_unlock() pair's overhead,
even including loop overhead, is far less than one nanosecond.
Since logscale plots are not all that happy with zero values, provide
picoseconds as decimals.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Current runs show PREEMPT=n rcu_read_lock()/rcu_read_unlock() pairs
consuming between 20 and 30 nanoseconds, when in fact the actual value is
zero, give or take the barrier() asm's effect on compiler optimizations.
The additional overhead is caused by function calls through pointers
(especially in these days of Spectre mitigations) and perhaps also
needless argument passing, a non-const loop limit, and an upcounting loop.
This commit therefore combines the ->readlock() and ->readunlock()
function pointers into a single ->readsection() function pointer that
takes the loop count as a const parameter and keeps any data passed
from the read-lock to the read-unlock internal to this new function.
These changes reduce the measured overhead of the aforementioned
PREEMPT=n rcu_read_lock()/rcu_read_unlock() pairs from between 20 and
30 nanoseconds to somewhere south of 500 picoseconds.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds an rcuperf module parameter named "holdoff" that
defaults to 10 seconds if refperf is built in and to zero otherwise.
The assumption is that all the CPUs are online by the time that the
modprobe and insmod commands are going to do anything, and that normal
systems will have all the CPUs online within ten seconds.
Larger systems may take many tens of seconds or even minutes to get
to this point, hence this being a module parameter instead of being a
hard-coded constant.
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit adds comments explaining why the readers have otherwise insane
levels of measurement overhead, namely that they are intended as a test
load for update-side performance measurements, not as a straight-up
read-side performance test.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Add a test for comparing the performance of RCU with various read-side
synchronization mechanisms. The test has proved useful for collecting
data and performing these comparisons.
Currently RCU, SRCU, reader-writer lock, reader-writer semaphore and
reference counting can be measured using refperf.perf_type parameter.
Each invocation of the test runs measures performance of a specific
mechanism.
The maximum number of CPUs to concurrently run readers on is chosen by
the test itself and is 75% of the total number of CPUs. So if you had 24
CPUs, the test runs with a maximum of 18 parallel readers.
A number of experiments are conducted, and in each experiment, the
number of readers is increased by 1, upto the 75% of CPUs mark. During
each experiment, all readers execute an empty loop with refperf.loops
iterations and time the total loop duration. This is then averaged.
Example output:
Parameters "refperf.perf_type=srcu refperf.loops=2000000" looks like:
[ 3.347133] srcu-ref-perf:
[ 3.347133] Threads Time(ns)
[ 3.347133] 1 36
[ 3.347133] 2 34
[ 3.347133] 3 34
[ 3.347133] 4 34
[ 3.347133] 5 33
[ 3.347133] 6 33
[ 3.347133] 7 33
[ 3.347133] 8 33
[ 3.347133] 9 33
[ 3.347133] 10 33
[ 3.347133] 11 33
[ 3.347133] 12 33
[ 3.347133] 13 33
[ 3.347133] 14 33
[ 3.347133] 15 32
[ 3.347133] 16 33
[ 3.347133] 17 33
[ 3.347133] 18 34
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
wait_event() already retries if the condition for the wake up is not
satisifed after wake up. Remove them from the rcuperf test.
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit declares trc_n_readers_need_end and trc_wait static and
replaced a "&" with "&&". The "&" happened to work because the values
are bool, but accidents waiting to happen and all that...
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The show_rcu_tasks_gp_kthreads() function is not invoked by Tiny RCU,
but is nevertheless defined in Tiny RCU builds that enable Tasks Trace
RCU. This commit therefore conditionally compiles this function so
that it is defined only in builds that actually use it.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Although this is in some strict sense unnecessary, it is good to allow
the compiler to compare the function declaration with its definition.
This commit therefore adds a #include of linux/rcupdate_trace.h to
kernel/rcu/update.c.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The rcu_tasks_postscan() function is not used outside of RCU's tasks.h
file, so this commit makes it be static.
Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
This commit converts the long-standing schedule_timeout_interruptible()
and schedule_timeout_uninterruptible() calls used by the various Tasks
RCU's grace-period kthreads to schedule_timeout_idle(). This conversion
avoids polluting the load-average with Tasks-RCU-related sleeping.
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Update the kvfree_call_rcu() function with head-less support.
This allows RCU to reclaim objects without an embedded rcu_head.
tree-RCU:
We introduce two chains of arrays to store SLAB-backed and vmalloc
pointers, each. Storage in either of these arrays does not require
embedding an rcu_head within the object.
Maintaining the arrays may become impossible due to high memory
pressure. For such cases there is an emergency path. Objects with
rcu_head inside are just queued on a backup rcu_head list. Later on
that list is drained. As for the head-less variant, as the current
context can sleep, the following emergency measures are applied:
a) Synchronously wait until a grace period has elapsed.
b) Call kvfree().
tiny-RCU:
For double argument calls, there are no new changes in behavior. For
single argument call, kvfree() is directly inlined on the current
stack after a synchronize_rcu() call. Note that for tiny-RCU, any
call to synchronize_rcu() is actually a quiescent state, therefore
it does nothing.
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The following changes are introduced:
1. Rename rcu_invoke_kfree_callback() to rcu_invoke_kvfree_callback(),
as well as the associated trace events, so the rcu_kfree_callback(),
becomes rcu_kvfree_callback(). The reason is to be aligned with kvfree()
notation.
2. Rename __is_kfree_rcu_offset to __is_kvfree_rcu_offset. All RCU
paths use kvfree() now instead of kfree(), thus rename it.
3. Rename kfree_call_rcu() to the kvfree_call_rcu(). The reason is,
it is capable of freeing vmalloc() memory now. Do the same with
__kfree_rcu() macro, it becomes __kvfree_rcu(), the goal is the
same.
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Replace kfree() with kvfree() in rcu_reclaim_tiny().
This makes it possible to release either SLAB or vmalloc
objects after a GP.
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
To do so, we use an array of kvfree_rcu_bulk_data structures.
It consists of two elements:
- index number 0 corresponds to slab pointers.
- index number 1 corresponds to vmalloc pointers.
Keeping vmalloc pointers separated from slab pointers makes
it possible to invoke the right freeing API for the right
kind of pointer.
It also prepares us for future headless support for vmalloc
and SLAB objects. Such objects cannot be queued on a linked
list and are instead directly into an array.
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Co-developed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
In order to reduce the dynamic need for pages in kfree_rcu(),
pre-allocate a configurable number of pages per CPU and link
them in a list. When kfree_rcu() reclaims objects, the object's
container page is cached into a list instead of being released
to the low-level page allocator.
Such an approach provides O(1) access to free pages while also
reducing the number of requests to the page allocator. It also
makes the kfree_rcu() code to have free pages available during
a low memory condition.
A read-only sysfs parameter (rcu_min_cached_objs) reflects the
minimum number of allowed cached pages per CPU.
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The per-CPU variable is initialized at runtime in
kfree_rcu_batch_init(). This function is invoked before
'rcu_scheduler_active' is set to 'RCU_SCHEDULER_RUNNING'.
After the initialisation, '->initialized' is to true.
The raw_spin_lock is only acquired if '->initialized' is
set to true. The worqueue item is only used if 'rcu_scheduler_active'
set to RCU_SCHEDULER_RUNNING which happens after initialisation.
Use a static initializer for krc.lock and remove the runtime
initialisation of the lock. Since the lock can now be always
acquired, remove the '->initialized' check.
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Introduce helpers to lock and unlock per-cpu "kfree_rcu_cpu"
structures. That will make kfree_call_rcu() more readable
and prevent programming errors.
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
We can simplify KFREE_BULK_MAX_ENTR macro and get rid of
magic numbers which were used to make the structure to be
exactly one page.
Suggested-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
kfree_rcu()'s debug_objects logic uses the address of the object's
embedded rcu_head to queue/unqueue. Instead of this, make use of the
object's address itself as preparation for future headless kfree_rcu()
support.
Reviewed-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
It is possible that one of the channels cannot be detached
because its free channel is busy and previously queued data
has not been processed yet. On the other hand, another
channel can be successfully detached causing the monitor
work to stop.
Prevent that by rescheduling the monitor work if there are
any channels in the pending state after a detach attempt.
Fixes: 34c8817455 ("rcu: Support kfree_bulk() interface in kfree_rcu()")
Acked-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
To keep the kfree_rcu() code working in purely atomic sections on RT,
such as non-threaded IRQ handlers and raw spinlock sections, avoid
calling into the page allocator which uses sleeping locks on RT.
In fact, even if the caller is preemptible, the kfree_rcu() code is
not, as the krcp->lock is a raw spinlock.
Calling into the page allocator is optional and avoiding it should be
Ok, especially with the page pre-allocation support in future patches.
Such pre-allocation would further avoid the a need for a dynamically
allocated page in the first place.
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Reviewed-by: Uladzislau Rezki <urezki@gmail.com>
Co-developed-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
On PREEMPT_RT kernels, the krcp spinlock gets converted to an rt-mutex
and causes kfree_rcu() callers to sleep. This makes it unusable for
callers in purely atomic sections such as non-threaded IRQ handlers and
raw spinlock sections. Fix it by converting the spinlock to a raw
spinlock.
Vetting all code paths, there is no reason to believe that the raw
spinlock will hurt RT latencies as it is not held for a long time.
Cc: bigeasy@linutronix.de
Cc: Uladzislau Rezki <urezki@gmail.com>
Reviewed-by: Uladzislau Rezki <urezki@gmail.com>
Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
There are some kernel-doc warnings:
./kernel/rcu/tree.c:2915: warning: Function parameter or member 'count' not described in 'kfree_rcu_cpu'
This commit therefore moves the comment for "count" to the kernel-doc
markup.
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Fix kernel-doc warning:
../kernel/rcu/tree.c:959: warning: Excess function parameter 'irq' description in 'rcu_nmi_enter'
Fixes: cf7614e13c ("rcu: Refactor rcu_{nmi,irq}_{enter,exit}()")
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Byungchul Park <byungchul.park@lge.com>
Cc: Joel Fernandes (Google) <joel@joelfernandes.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The ->grpnum field in the rcu_node structure contains the bit position
in this structure's parent's bitmasks, which is not the CPU number.
This commit therefore adjusts this field's comment accordingly.
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The ->grplo and ->grphi fields store the lowest and highest CPU number
covered by to a rcu_node structure, which is not the group number.
This commit therefore adjusts these fields' comments to match reality.
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Because gp_max is protected by root rcu_node's lock, this commit moves
the gp_max definition to the region of the rcu_node structure containing
fields protected by this lock.
Signed-off-by: Wei Yang <richard.weiyang@linux.alibaba.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The count and scan can be separated in time, and there is a fair chance
that all work is already done when the scan starts, which might in turn
result in a needless retry. This commit therefore avoids this retry by
returning SHRINK_STOP.
Reviewed-by: Uladzislau Rezki (Sony) <urezki@gmail.com>
Signed-off-by: Peter Enderborg <peter.enderborg@sony.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Coccinelle reports a warning
WARNING: Assignment of 0/1 to bool variable
The root cause is that the variable lastphase is a bool, but is
initialised with integer 1. This commit therefore replaces the 1 with
a true.
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Currently, lockdep_rcu_suspicious() complains twice about RCU read-side
critical sections being invoked from within extended quiescent states,
for example:
RCU used illegally from idle CPU!
rcu_scheduler_active = 2, debug_locks = 1
RCU used illegally from extended quiescent state!
This commit therefore saves a couple lines of code and one line of
console-log output by eliminating the first of these two complaints.
Link: https://lore.kernel.org/lkml/87wo4wnpzb.fsf@nanos.tec.linutronix.de
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
The objtool complains about the call to rcu_cleanup_after_idle() from
rcu_nmi_enter(), so this commit adds instrumentation_begin() before that
call and instrumentation_end() after it.
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
