The patch to add anonymous vma names causes a build failure in some
configurations:
include/linux/mm_types.h: In function 'is_same_vma_anon_name':
include/linux/mm_types.h:924:37: error: implicit declaration of function 'strcmp' [-Werror=implicit-function-declaration]
924 | return name && vma_name && !strcmp(name, vma_name);
| ^~~~~~
include/linux/mm_types.h:22:1: note: 'strcmp' is defined in header '<string.h>'; did you forget to '#include <string.h>'?
This should not really be part of linux/mm_types.h in the first place,
as that header is meant to only contain structure defintions and need a
minimum set of indirect includes itself.
While the header clearly includes more than it should at this point,
let's not make it worse by including string.h as well, which would pull
in the expensive (compile-speed wise) fortify-string logic.
Move the new functions into a separate header that only needs to be
included in a couple of locations.
Link: https://lkml.kernel.org/r/20211207125710.2503446-1-arnd@kernel.org
Fixes: "mm: add a field to store names for private anonymous memory"
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Colin Cross <ccross@google.com>
Cc: Eric Biederman <ebiederm@xmission.com>
Cc: Kees Cook <keescook@chromium.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
In many userspace applications, and especially in VM based applications
like Android uses heavily, there are multiple different allocators in
use. At a minimum there is libc malloc and the stack, and in many cases
there are libc malloc, the stack, direct syscalls to mmap anonymous
memory, and multiple VM heaps (one for small objects, one for big
objects, etc.). Each of these layers usually has its own tools to
inspect its usage; malloc by compiling a debug version, the VM through
heap inspection tools, and for direct syscalls there is usually no way
to track them.
On Android we heavily use a set of tools that use an extended version of
the logic covered in Documentation/vm/pagemap.txt to walk all pages
mapped in userspace and slice their usage by process, shared (COW) vs.
unique mappings, backing, etc. This can account for real physical
memory usage even in cases like fork without exec (which Android uses
heavily to share as many private COW pages as possible between
processes), Kernel SamePage Merging, and clean zero pages. It produces
a measurement of the pages that only exist in that process (USS, for
unique), and a measurement of the physical memory usage of that process
with the cost of shared pages being evenly split between processes that
share them (PSS).
If all anonymous memory is indistinguishable then figuring out the real
physical memory usage (PSS) of each heap requires either a pagemap
walking tool that can understand the heap debugging of every layer, or
for every layer's heap debugging tools to implement the pagemap walking
logic, in which case it is hard to get a consistent view of memory
across the whole system.
Tracking the information in userspace leads to all sorts of problems.
It either needs to be stored inside the process, which means every
process has to have an API to export its current heap information upon
request, or it has to be stored externally in a filesystem that somebody
needs to clean up on crashes. It needs to be readable while the process
is still running, so it has to have some sort of synchronization with
every layer of userspace. Efficiently tracking the ranges requires
reimplementing something like the kernel vma trees, and linking to it
from every layer of userspace. It requires more memory, more syscalls,
more runtime cost, and more complexity to separately track regions that
the kernel is already tracking.
This patch adds a field to /proc/pid/maps and /proc/pid/smaps to show a
userspace-provided name for anonymous vmas. The names of named
anonymous vmas are shown in /proc/pid/maps and /proc/pid/smaps as
[anon:<name>].
Userspace can set the name for a region of memory by calling
prctl(PR_SET_VMA, PR_SET_VMA_ANON_NAME, start, len, (unsigned long)name)
Setting the name to NULL clears it. The name length limit is 80 bytes
including NUL-terminator and is checked to contain only printable ascii
characters (including space), except '[',']','\','$' and '`'.
Ascii strings are being used to have a descriptive identifiers for vmas,
which can be understood by the users reading /proc/pid/maps or
/proc/pid/smaps. Names can be standardized for a given system and they
can include some variable parts such as the name of the allocator or a
library, tid of the thread using it, etc.
The name is stored in a pointer in the shared union in vm_area_struct
that points to a null terminated string. Anonymous vmas with the same
name (equivalent strings) and are otherwise mergeable will be merged.
The name pointers are not shared between vmas even if they contain the
same name. The name pointer is stored in a union with fields that are
only used on file-backed mappings, so it does not increase memory usage.
CONFIG_ANON_VMA_NAME kernel configuration is introduced to enable this
feature. It keeps the feature disabled by default to prevent any
additional memory overhead and to avoid confusing procfs parsers on
systems which are not ready to support named anonymous vmas.
The patch is based on the original patch developed by Colin Cross, more
specifically on its latest version [1] posted upstream by Sumit Semwal.
It used a userspace pointer to store vma names. In that design, name
pointers could be shared between vmas. However during the last
upstreaming attempt, Kees Cook raised concerns [2] about this approach
and suggested to copy the name into kernel memory space, perform
validity checks [3] and store as a string referenced from
vm_area_struct.
One big concern is about fork() performance which would need to strdup
anonymous vma names. Dave Hansen suggested experimenting with
worst-case scenario of forking a process with 64k vmas having longest
possible names [4]. I ran this experiment on an ARM64 Android device
and recorded a worst-case regression of almost 40% when forking such a
process.
This regression is addressed in the followup patch which replaces the
pointer to a name with a refcounted structure that allows sharing the
name pointer between vmas of the same name. Instead of duplicating the
string during fork() or when splitting a vma it increments the refcount.
[1] https://lore.kernel.org/linux-mm/20200901161459.11772-4-sumit.semwal@linaro.org/
[2] https://lore.kernel.org/linux-mm/202009031031.D32EF57ED@keescook/
[3] https://lore.kernel.org/linux-mm/202009031022.3834F692@keescook/
[4] https://lore.kernel.org/linux-mm/5d0358ab-8c47-2f5f-8e43-23b89d6a8e95@intel.com/
Changes for prctl(2) manual page (in the options section):
PR_SET_VMA
Sets an attribute specified in arg2 for virtual memory areas
starting from the address specified in arg3 and spanning the
size specified in arg4. arg5 specifies the value of the attribute
to be set. Note that assigning an attribute to a virtual memory
area might prevent it from being merged with adjacent virtual
memory areas due to the difference in that attribute's value.
Currently, arg2 must be one of:
PR_SET_VMA_ANON_NAME
Set a name for anonymous virtual memory areas. arg5 should
be a pointer to a null-terminated string containing the
name. The name length including null byte cannot exceed
80 bytes. If arg5 is NULL, the name of the appropriate
anonymous virtual memory areas will be reset. The name
can contain only printable ascii characters (including
space), except '[',']','\','$' and '`'.
This feature is available only if the kernel is built with
the CONFIG_ANON_VMA_NAME option enabled.
[surenb@google.com: docs: proc.rst: /proc/PID/maps: fix malformed table]
Link: https://lkml.kernel.org/r/20211123185928.2513763-1-surenb@google.com
[surenb: rebased over v5.15-rc6, replaced userpointer with a kernel copy,
added input sanitization and CONFIG_ANON_VMA_NAME config. The bulk of the
work here was done by Colin Cross, therefore, with his permission, keeping
him as the author]
Link: https://lkml.kernel.org/r/20211019215511.3771969-2-surenb@google.com
Signed-off-by: Colin Cross <ccross@google.com>
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jan Glauber <jan.glauber@gmail.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Stultz <john.stultz@linaro.org>
Cc: Mel Gorman <mgorman@suse.de>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Rob Landley <rob@landley.net>
Cc: "Serge E. Hallyn" <serge.hallyn@ubuntu.com>
Cc: Shaohua Li <shli@fusionio.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The new flag MODULE_INIT_COMPRESSED_FILE unintentionally trips check in
module_sig_check(). The check was supposed to catch case when version
info or magic was removed from a signed module, making signature
invalid, but it was coded too broadly and was catching this new flag as
well.
Change the check to only test the 2 particular flags affecting signature
validity.
Fixes: b1ae6dc41e ("module: add in-kernel support for decompressing")
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Reviewed-by: Douglas Anderson <dianders@chromium.org>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Since referencing user space pointers is special, if the user wants to
filter on a field that is a pointer to user space, then they need to
specify it.
Add a ".ustring" attribute to the field name for filters to state that the
field is pointing to user space such that the kernel can take the
appropriate action to read that pointer.
Link: https://lore.kernel.org/all/yt9d8rvmt2jq.fsf@linux.ibm.com/
Fixes: 77360f9bbc ("tracing: Add test for user space strings when filtering on string pointers")
Tested-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
If start_per_cpu_kthreads() called from osnoise_workload_start() returns
error, event hooks are left in broken state: unhook_irq_events() called
but unhook_thread_events() and unhook_softirq_events() not called, and
trace_osnoise_callback_enabled flag not cleared.
On the next tracer enable, hooks get not installed due to
trace_osnoise_callback_enabled flag.
And on the further tracer disable an attempt to remove non-installed
hooks happened, hitting a WARN_ON_ONCE() in tracepoint_remove_func().
Fix the error path by adding the missing part of cleanup.
While at this, introduce osnoise_unhook_events() to avoid code
duplication between this error path and normal tracer disable.
Link: https://lkml.kernel.org/r/20220109153459.3701773-1-nikita.yushchenko@virtuozzo.com
Cc: stable@vger.kernel.org
Fixes: bce29ac9ce ("trace: Add osnoise tracer")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Nikita Yushchenko <nikita.yushchenko@virtuozzo.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pingfan reported that the following causes a fault:
echo "filename ~ \"cpu\"" > events/syscalls/sys_enter_openat/filter
echo 1 > events/syscalls/sys_enter_at/enable
The reason is that trace event filter treats the user space pointer
defined by "filename" as a normal pointer to compare against the "cpu"
string. The following bug happened:
kvm-03-guest16 login: [72198.026181] BUG: unable to handle page fault for address: 00007fffaae8ef60
#PF: supervisor read access in kernel mode
#PF: error_code(0x0001) - permissions violation
PGD 80000001008b7067 P4D 80000001008b7067 PUD 2393f1067 PMD 2393ec067 PTE 8000000108f47867
Oops: 0001 [#1] PREEMPT SMP PTI
CPU: 1 PID: 1 Comm: systemd Kdump: loaded Not tainted 5.14.0-32.el9.x86_64 #1
Hardware name: Red Hat KVM, BIOS 0.5.1 01/01/2011
RIP: 0010:strlen+0x0/0x20
Code: 48 89 f9 74 09 48 83 c1 01 80 39 00 75 f7 31 d2 44 0f b6 04 16 44 88 04 11
48 83 c2 01 45 84 c0 75 ee c3 0f 1f 80 00 00 00 00 <80> 3f 00 74 10 48 89 f8
48 83 c0 01 80 38 00 75 f7 48 29 f8 c3 31
RSP: 0018:ffffb5b900013e48 EFLAGS: 00010246
RAX: 0000000000000018 RBX: ffff8fc1c49ede00 RCX: 0000000000000000
RDX: 0000000000000020 RSI: ffff8fc1c02d601c RDI: 00007fffaae8ef60
RBP: 00007fffaae8ef60 R08: 0005034f4ddb8ea4 R09: 0000000000000000
R10: ffff8fc1c02d601c R11: 0000000000000000 R12: ffff8fc1c8a6e380
R13: 0000000000000000 R14: ffff8fc1c02d6010 R15: ffff8fc1c00453c0
FS: 00007fa86123db40(0000) GS:ffff8fc2ffd00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fffaae8ef60 CR3: 0000000102880001 CR4: 00000000007706e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
PKRU: 55555554
Call Trace:
filter_pred_pchar+0x18/0x40
filter_match_preds+0x31/0x70
ftrace_syscall_enter+0x27a/0x2c0
syscall_trace_enter.constprop.0+0x1aa/0x1d0
do_syscall_64+0x16/0x90
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fa861d88664
The above happened because the kernel tried to access user space directly
and triggered a "supervisor read access in kernel mode" fault. Worse yet,
the memory could not even be loaded yet, and a SEGFAULT could happen as
well. This could be true for kernel space accessing as well.
To be even more robust, test both kernel and user space strings. If the
string fails to read, then simply have the filter fail.
Note, TASK_SIZE is used to determine if the pointer is user or kernel space
and the appropriate strncpy_from_kernel/user_nofault() function is used to
copy the memory. For some architectures, the compare to TASK_SIZE may always
pick user space or kernel space. If it gets it wrong, the only thing is that
the filter will fail to match. In the future, this needs to be fixed to have
the event denote which should be used. But failing a filter is much better
than panicing the machine, and that can be solved later.
Link: https://lore.kernel.org/all/20220107044951.22080-1-kernelfans@gmail.com/
Link: https://lkml.kernel.org/r/20220110115532.536088fd@gandalf.local.home
Cc: stable@vger.kernel.org
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Tom Zanussi <zanussi@kernel.org>
Reported-by: Pingfan Liu <kernelfans@gmail.com>
Tested-by: Pingfan Liu <kernelfans@gmail.com>
Fixes: 87a342f5db ("tracing/filters: Support filtering for char * strings")
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Disabling only bottom halves via local_bh_disable() disables also
preemption but this remains invisible to tracing. On a CONFIG_PREEMPT
kernel one might wonder why there is no scheduling happening despite the
N flag in the trace. The reason might be the a rcu_read_lock_bh()
section.
Add a 'b' to the tracing output if in task context with disabled bottom
halves.
Link: https://lkml.kernel.org/r/YbcbtdtC/bjCKo57@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
Pull MSI irq updates from Thomas Gleixner:
"Rework of the MSI interrupt infrastructure.
This is a treewide cleanup and consolidation of MSI interrupt handling
in preparation for further changes in this area which are necessary
to:
- address existing shortcomings in the VFIO area
- support the upcoming Interrupt Message Store functionality which
decouples the message store from the PCI config/MMIO space"
* tag 'irq-msi-2022-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (94 commits)
genirq/msi: Populate sysfs entry only once
PCI/MSI: Unbreak pci_irq_get_affinity()
genirq/msi: Convert storage to xarray
genirq/msi: Simplify sysfs handling
genirq/msi: Add abuse prevention comment to msi header
genirq/msi: Mop up old interfaces
genirq/msi: Convert to new functions
genirq/msi: Make interrupt allocation less convoluted
platform-msi: Simplify platform device MSI code
platform-msi: Let core code handle MSI descriptors
bus: fsl-mc-msi: Simplify MSI descriptor handling
soc: ti: ti_sci_inta_msi: Remove ti_sci_inta_msi_domain_free_irqs()
soc: ti: ti_sci_inta_msi: Rework MSI descriptor allocation
NTB/msi: Convert to msi_on_each_desc()
PCI: hv: Rework MSI handling
powerpc/mpic_u3msi: Use msi_for_each-desc()
powerpc/fsl_msi: Use msi_for_each_desc()
powerpc/pasemi/msi: Convert to msi_on_each_dec()
powerpc/cell/axon_msi: Convert to msi_on_each_desc()
powerpc/4xx/hsta: Rework MSI handling
...
Pull timer updates from Thomas Gleixner:
"Updates for the time(r) subsystem:
Core:
- Make the clocksource watchdog more robust by better validation
checks of the measurement.
Drivers:
- New drivers for MStar and SSD20xd SOCs
- The usual cleanups and improvements all over the place"
* tag 'timers-core-2022-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
dt-bindings: timer: Add Mstar MSC313e timer devicetree bindings documentation
clocksource/drivers/msc313e: Add support for ssd20xd-based platforms
clocksource/drivers: Add MStar MSC313e timer support
clocksource/drivers/pistachio: Fix -Wunused-but-set-variable warning
clocksource/drivers/timer-imx-sysctr: Set cpumask to cpu_possible_mask
clocksource/drivers/imx-sysctr: Mark two variable with __ro_after_init
clocksource/drivers/renesas,ostm: Make RENESAS_OSTM symbol visible
clocksource/drivers/renesas-ostm: Add RZ/G2L OSTM support
dt-bindings: timer: renesas: ostm: Document Renesas RZ/G2L OSTM
clocksource/drivers/exynos_mct: Fix silly typo resulting in checkpatch warning
clocksource: Reduce the default clocksource_watchdog() retries to 2
clocksource: Avoid accidental unstable marking of clocksources
dt-bindings: timer: tpm-timer: Add imx8ulp compatible string
reset: Add of_reset_control_get_optional_exclusive()
clocksource/drivers/exynos_mct: Refactor resources allocation
dt-bindings: timer: remove rockchip,rk3066-timer compatible string from rockchip,rk-timer.yaml
dt-bindings: timer: cadence_ttc: Add power-domains
Pull irq updates from Thomas Gleixner:
"Updates for the interrupt subsystem:
Core:
- Provide a new interface for affinity hints to provide a separation
between hint and actual affinity change which has become a hidden
property of the current interface
- Fix up the in tree usage of the affinity hint interfaces
Drivers:
- No new irqchip drivers!
- Fix GICv3 redistributor table reservation with RT across kexec
- Fix GICv4.1 redistributor view of the VPE table across kexec
- Add support for extra interrupts on spear-shirq
- Make obtaining some interrupts optional for the Renesas drivers
- Various cleanups and bug fixes"
* tag 'irq-core-2022-01-13' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
irqchip/renesas-intc-irqpin: Use platform_get_irq_optional() to get the interrupt
irqchip/renesas-irqc: Use platform_get_irq_optional() to get the interrupt
irqchip/gic-v4: Disable redistributors' view of the VPE table at boot time
irqchip/ingenic-tcu: Use correctly sized arguments for bit field
irqchip/gic-v2m: Add const to of_device_id
irqchip/imx-gpcv2: Mark imx_gpcv2_instance with __ro_after_init
irqchip/spear-shirq: Add support for IRQ 0..6
irqchip/gic-v3-its: Limit memreserve cpuhp state lifetime
irqchip/gic-v3-its: Postpone LPI pending table freeing and memreserve
irqchip/gic-v3-its: Give the percpu rdist struct its own flags field
net/mlx4: Use irq_update_affinity_hint()
net/mlx5: Use irq_set_affinity_and_hint()
hinic: Use irq_set_affinity_and_hint()
scsi: lpfc: Use irq_set_affinity()
mailbox: Use irq_update_affinity_hint()
ixgbe: Use irq_update_affinity_hint()
be2net: Use irq_update_affinity_hint()
enic: Use irq_update_affinity_hint()
RDMA/irdma: Use irq_update_affinity_hint()
scsi: mpt3sas: Use irq_set_affinity_and_hint()
...
There is a spelling mistake in a pr_err error message. Fix it.
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Pull perf updates from Borislav Petkov:
"Cleanup of the perf/kvm interaction."
* tag 'perf_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf: Drop guest callback (un)register stubs
KVM: arm64: Drop perf.c and fold its tiny bits of code into arm.c
KVM: arm64: Hide kvm_arm_pmu_available behind CONFIG_HW_PERF_EVENTS=y
KVM: arm64: Convert to the generic perf callbacks
KVM: x86: Move Intel Processor Trace interrupt handler to vmx.c
KVM: Move x86's perf guest info callbacks to generic KVM
KVM: x86: More precisely identify NMI from guest when handling PMI
KVM: x86: Drop current_vcpu for kvm_running_vcpu + kvm_arch_vcpu variable
perf/core: Use static_call to optimize perf_guest_info_callbacks
perf: Force architectures to opt-in to guest callbacks
perf: Add wrappers for invoking guest callbacks
perf/core: Rework guest callbacks to prepare for static_call support
perf: Drop dead and useless guest "support" from arm, csky, nds32 and riscv
perf: Stop pretending that perf can handle multiple guest callbacks
KVM: x86: Register Processor Trace interrupt hook iff PT enabled in guest
KVM: x86: Register perf callbacks after calling vendor's hardware_setup()
perf: Protect perf_guest_cbs with RCU
The commit 1f1562fcd0 ("cgroup/cpuset: Don't let child cpusets
restrict parent in default hierarchy") inteded to relax the check only
on the default hierarchy (or v2 mode) but it dropped the check in v1
too.
This patch returns and separates the legacy-only validations so that
they can be considered only in the v1 mode, which should enforce the old
constraints for the sake of compatibility.
Fixes: 1f1562fcd0 ("cgroup/cpuset: Don't let child cpusets restrict parent in default hierarchy")
Suggested-by: Waiman Long <longman@redhat.com>
Signed-off-by: Michal Koutný <mkoutny@suse.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Add the description of @kargs in cgroup_can_fork() and
cgroup_post_fork() kernel-doc comment to remove warnings found
by running scripts/kernel-doc, which is caused by using 'make W=1'.
kernel/cgroup/cgroup.c:6235: warning: Function parameter or member
'kargs' not described in 'cgroup_can_fork'
kernel/cgroup/cgroup.c:6296: warning: Function parameter or member
'kargs' not described in 'cgroup_post_fork'
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Instead of retrieve current bstat to cur and copy it to delta, let's use
delta directly.
This saves one copy operation and has the same code convention as
propagating delta to parent.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
In function cgroup_base_stat_flush(), we update cgroup_base_stat by
getting rstatc->bstat and adjust delta to related fields.
There are two convention to assign cgroup_base_stat in this function:
* rstat2 = rstat1
* rstat2.cputime = rstat1.cputime
The second convention may make audience think just field "cputime" is
updated, while cputime is the only field in cgroup_base_stat.
Let's use the same convention to eliminate this confusion.
Signed-off-by: Wei Yang <richard.weiyang@gmail.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Pull driver core updates from Greg KH:
"Here is the set of changes for the driver core for 5.17-rc1.
Lots of little things here, including:
- kobj_type cleanups
- auxiliary_bus documentation updates
- auxiliary_device conversions for some drivers (relevant subsystems
all have provided acks for these)
- kernfs lock contention reduction for some workloads
- other tiny cleanups and changes.
All of these have been in linux-next for a while with no reported
issues"
* tag 'driver-core-5.17-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (43 commits)
kobject documentation: remove default_attrs information
drivers/firmware: Add missing platform_device_put() in sysfb_create_simplefb
debugfs: lockdown: Allow reading debugfs files that are not world readable
driver core: Make bus notifiers in right order in really_probe()
driver core: Move driver_sysfs_remove() after driver_sysfs_add()
firmware: edd: remove empty default_attrs array
firmware: dmi-sysfs: use default_groups in kobj_type
qemu_fw_cfg: use default_groups in kobj_type
firmware: memmap: use default_groups in kobj_type
sh: sq: use default_groups in kobj_type
headers/uninline: Uninline single-use function: kobject_has_children()
devtmpfs: mount with noexec and nosuid
driver core: Simplify async probe test code by using ktime_ms_delta()
nilfs2: use default_groups in kobj_type
kobject: remove kset from struct kset_uevent_ops callbacks
driver core: make kobj_type constant.
driver core: platform: document registration-failure requirement
vdpa/mlx5: Use auxiliary_device driver data helpers
net/mlx5e: Use auxiliary_device driver data helpers
soundwire: intel: Use auxiliary_device driver data helpers
...
Pull block updates from Jens Axboe:
- Unify where the struct request handling code is located in the blk-mq
code (Christoph)
- Header cleanups (Christoph)
- Clean up the io_context handling code (Christoph, me)
- Get rid of ->rq_disk in struct request (Christoph)
- Error handling fix for add_disk() (Christoph)
- request allocation cleanusp (Christoph)
- Documentation updates (Eric, Matthew)
- Remove trivial crypto unregister helper (Eric)
- Reduce shared tag overhead (John)
- Reduce poll_stats memory overhead (me)
- Known indirect function call for dio (me)
- Use atomic references for struct request (me)
- Support request list issue for block and NVMe (me)
- Improve queue dispatch pinning (Ming)
- Improve the direct list issue code (Keith)
- BFQ improvements (Jan)
- Direct completion helper and use it in mmc block (Sebastian)
- Use raw spinlock for the blktrace code (Wander)
- fsync error handling fix (Ye)
- Various fixes and cleanups (Lukas, Randy, Yang, Tetsuo, Ming, me)
* tag 'for-5.17/block-2022-01-11' of git://git.kernel.dk/linux-block: (132 commits)
MAINTAINERS: add entries for block layer documentation
docs: block: remove queue-sysfs.rst
docs: sysfs-block: document virt_boundary_mask
docs: sysfs-block: document stable_writes
docs: sysfs-block: fill in missing documentation from queue-sysfs.rst
docs: sysfs-block: add contact for nomerges
docs: sysfs-block: sort alphabetically
docs: sysfs-block: move to stable directory
block: don't protect submit_bio_checks by q_usage_counter
block: fix old-style declaration
nvme-pci: fix queue_rqs list splitting
block: introduce rq_list_move
block: introduce rq_list_for_each_safe macro
block: move rq_list macros to blk-mq.h
block: drop needless assignment in set_task_ioprio()
block: remove unnecessary trailing '\'
bio.h: fix kernel-doc warnings
block: check minor range in device_add_disk()
block: use "unsigned long" for blk_validate_block_size().
block: fix error unwinding in device_add_disk
...
Pull dma-mapping updates from Christoph Hellwig:
- refactor the dma-direct coherent allocator
- turn an macro into an inline in scatterlist.h (Logan Gunthorpe)
* tag 'dma-mapping-5.17' of git://git.infradead.org/users/hch/dma-mapping:
lib/scatterlist: cleanup macros into static inline functions
dma-direct: add a dma_direct_use_pool helper
dma-direct: factor the swiotlb code out of __dma_direct_alloc_pages
dma-direct: drop two CONFIG_DMA_RESTRICTED_POOL conditionals
dma-direct: warn if there is no pool for force unencrypted allocations
dma-direct: fail allocations that can't be made coherent
dma-direct: refactor the !coherent checks in dma_direct_alloc
dma-direct: factor out a helper for DMA_ATTR_NO_KERNEL_MAPPING allocations
dma-direct: clean up the remapping checks in dma_direct_alloc
dma-direct: always leak memory that can't be re-encrypted
dma-direct: don't call dma_set_decrypted for remapped allocations
dma-direct: factor out dma_set_{de,en}crypted helpers
It is only modified in associated CPU, so it doesn't need to be atomic.
tj: Comment updated.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The wakeup code in wq_worker_sleeping() is the same as wake_up_worker().
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
The access to idle_list in wq_worker_sleeping() is changed to be
protected by pool->lock, so the comments above idle_list can be changed
to "L:" which is the meaning of "access with pool->lock held".
And the outdated comments in wq_worker_sleeping() is removed since
the function is not called with rq lock held any more, idle_list is
dereferenced with pool lock now.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
In wq_worker_sleeping(), the access to worklist is protected by the
pool->lock, so the memory barrier is unneeded.
Signed-off-by: Lai Jiangshan <laijs@linux.alibaba.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Current scheme of having userspace decompress kernel modules before
loading them into the kernel runs afoul of LoadPin security policy, as
it loses link between the source of kernel module on the disk and binary
blob that is being loaded into the kernel. To solve this issue let's
implement decompression in kernel, so that we can pass a file descriptor
of compressed module file into finit_module() which will keep LoadPin
happy.
To let userspace know what compression/decompression scheme kernel
supports it will create /sys/module/compression attribute. kmod can read
this attribute and decide if it can pass compressed file to
finit_module(). New MODULE_INIT_COMPRESSED_DATA flag indicates that the
kernel should attempt to decompress the data read from file descriptor
prior to trying load the module.
To simplify things kernel will only implement single decompression
method matching compression method selected when generating modules.
This patch implements gzip and xz; more can be added later,
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Since commit e513cc1c07 ("module: Remove stop_machine from module
unloading") this comment is no longer correct. Remove it.
Signed-off-by: Yu Chen <chen.yu@easystack.cn>
Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
Pull locking updates from Borislav Petkov:
"Lots of cleanups and preparation. Highlights:
- futex: Cleanup and remove runtime futex_cmpxchg detection
- rtmutex: Some fixes for the PREEMPT_RT locking infrastructure
- kcsan: Share owner_on_cpu() between mutex,rtmutex and rwsem and
annotate the racy owner->on_cpu access *once*.
- atomic64: Dead-Code-Elemination"
[ Description above by Peter Zijlstra ]
* tag 'locking_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
locking/atomic: atomic64: Remove unusable atomic ops
futex: Fix additional regressions
locking: Allow to include asm/spinlock_types.h from linux/spinlock_types_raw.h
x86/mm: Include spinlock_t definition in pgtable.
locking: Mark racy reads of owner->on_cpu
locking: Make owner_on_cpu() into <linux/sched.h>
lockdep/selftests: Adapt ww-tests for PREEMPT_RT
lockdep/selftests: Skip the softirq related tests on PREEMPT_RT
lockdep/selftests: Unbalanced migrate_disable() & rcu_read_lock().
lockdep/selftests: Avoid using local_lock_{acquire|release}().
lockdep: Remove softirq accounting on PREEMPT_RT.
locking/rtmutex: Add rt_mutex_lock_nest_lock() and rt_mutex_lock_killable().
locking/rtmutex: Squash self-deadlock check for ww_rt_mutex.
locking: Remove rt_rwlock_is_contended().
sched: Trigger warning if ->migration_disabled counter underflows.
futex: Fix sparc32/m68k/nds32 build regression
futex: Remove futex_cmpxchg detection
futex: Ensure futex_atomic_cmpxchg_inatomic() is present
kernel/locking: Use a pointer in ww_mutex_trylock().
Pull scheduler updates from Borislav Petkov:
"Mostly minor things this time; some highlights:
- core-sched: Add 'Forced Idle' accounting; this allows to track how
much CPU time is 'lost' due to core scheduling constraints.
- psi: Fix for MEM_FULL; a task running reclaim would be counted as a
runnable task and prevent MEM_FULL from being reported.
- cpuacct: Long standing fixes for some cgroup accounting issues.
- rt: Bandwidth timer could, under unusual circumstances, be failed
to armed, leading to indefinite throttling."
[ Description above by Peter Zijlstra ]
* tag 'sched_core_for_v5.17_rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
sched/fair: Replace CFS internal cpu_util() with cpu_util_cfs()
sched/fair: Cleanup task_util and capacity type
sched/rt: Try to restart rt period timer when rt runtime exceeded
sched/fair: Document the slow path and fast path in select_task_rq_fair
sched/fair: Fix per-CPU kthread and wakee stacking for asym CPU capacity
sched/fair: Fix detection of per-CPU kthreads waking a task
sched/cpuacct: Make user/system times in cpuacct.stat more precise
sched/cpuacct: Fix user/system in shown cpuacct.usage*
cpuacct: Convert BUG_ON() to WARN_ON_ONCE()
cputime, cpuacct: Include guest time in user time in cpuacct.stat
psi: Fix PSI_MEM_FULL state when tasks are in memstall and doing reclaim
sched/core: Forced idle accounting
psi: Add a missing SPDX license header
psi: Remove repeated verbose comment
Pull audit updates from Paul Moore:
"Four audit patches for v5.17:
- Harden the code through additional use of the struct_size() macro
and zero-length arrays to flexible-array conversions.
- Ensure that processes which generate userspace audit records are
not exempt from the kernel's audit throttling when the audit queues
are being overrun"
* tag 'audit-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/audit:
audit: replace zero-length array with flexible-array member
audit: use struct_size() helper in audit_[send|make]_reply()
audit: ensure userspace is penalized the same as the kernel when under pressure
audit: use struct_size() helper in kmalloc()
Pull selinux updates from Paul Moore:
"Nothing too significant, but five SELinux patches for v5.17 that do
the following:
- Harden the code through additional use of the struct_size() macro
- Plug some memory leaks
- Clean up the code via removal of the security_add_mnt_opt() LSM
hook and minor tweaks to selinux_add_opt()
- Rename security_task_getsecid_subj() to better reflect its actual
behavior/use - now called security_current_getsecid_subj()"
* tag 'selinux-pr-20220110' of git://git.kernel.org/pub/scm/linux/kernel/git/pcmoore/selinux:
selinux: minor tweaks to selinux_add_opt()
selinux: fix potential memleak in selinux_add_opt()
security,selinux: remove security_add_mnt_opt()
selinux: Use struct_size() helper in kmalloc()
lsm: security_task_getsecid_subj() -> security_current_getsecid_subj()
Pull KCSAN updates from Paul McKenney:
"This provides KCSAN fixes and also the ability to take memory barriers
into account for weakly-ordered systems. This last can increase the
probability of detecting certain types of data races"
* tag 'kcsan.2022.01.09a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (29 commits)
kcsan: Only test clear_bit_unlock_is_negative_byte if arch defines it
kcsan: Avoid nested contexts reading inconsistent reorder_access
kcsan: Turn barrier instrumentation into macros
kcsan: Make barrier tests compatible with lockdep
kcsan: Support WEAK_MEMORY with Clang where no objtool support exists
compiler_attributes.h: Add __disable_sanitizer_instrumentation
objtool, kcsan: Remove memory barrier instrumentation from noinstr
objtool, kcsan: Add memory barrier instrumentation to whitelist
sched, kcsan: Enable memory barrier instrumentation
mm, kcsan: Enable barrier instrumentation
x86/qspinlock, kcsan: Instrument barrier of pv_queued_spin_unlock()
x86/barriers, kcsan: Use generic instrumentation for non-smp barriers
asm-generic/bitops, kcsan: Add instrumentation for barriers
locking/atomics, kcsan: Add instrumentation for barriers
locking/barriers, kcsan: Support generic instrumentation
locking/barriers, kcsan: Add instrumentation for barriers
kcsan: selftest: Add test case to check memory barrier instrumentation
kcsan: Ignore GCC 11+ warnings about TSan runtime support
kcsan: test: Add test cases for memory barrier instrumentation
kcsan: test: Match reordered or normal accesses
...
Pull RCU updates from Paul McKenney:
- Documentation updates, perhaps most notably Neil Brown's writeup of
the reference-counting analogy to RCU.
- Expedited grace-period cleanups.
- Remove CONFIG_RCU_FAST_NO_HZ due to lack of valid users. I have asked
around, posted a blog entry, and sent this series to LKML without
result.
- Miscellaneous fixes.
- RCU callback offloading updates, perhaps most notably Frederic
Weisbecker's updates allowing CPUs booted in the de-offloaded state
to be offloaded at runtime.
- nolibc fixes from Willy Tarreau and Anmar Faizi, but also including
Mark Brown's addition of gettid().
- RCU Tasks Trace fixes, including changes that increase the
scalability of call_rcu_tasks_trace() for the BPF folks (Martin Lau
and KP Singh).
- Various fixes including those from Wander Lairson Costa and Li
Zhijian.
- Fixes plus addition of tests for the increased call_rcu_tasks_trace()
scalability.
* tag 'rcu.2022.01.09a' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu: (87 commits)
rcu/nocb: Merge rcu_spawn_cpu_nocb_kthread() and rcu_spawn_one_nocb_kthread()
rcu/nocb: Allow empty "rcu_nocbs" kernel parameter
rcu/nocb: Create kthreads on all CPUs if "rcu_nocbs=" or "nohz_full=" are passed
rcu/nocb: Optimize kthreads and rdp initialization
rcu/nocb: Prepare nocb_cb_wait() to start with a non-offloaded rdp
rcu/nocb: Remove rcu_node structure from nocb list when de-offloaded
rcu-tasks: Use fewer callbacks queues if callback flood ends
rcu-tasks: Use separate ->percpu_dequeue_lim for callback dequeueing
rcu-tasks: Use more callback queues if contention encountered
rcu-tasks: Avoid raw-spinlocked wakeups from call_rcu_tasks_generic()
rcu-tasks: Count trylocks to estimate call_rcu_tasks() contention
rcu-tasks: Add rcupdate.rcu_task_enqueue_lim to set initial queueing
rcu-tasks: Make rcu_barrier_tasks*() handle multiple callback queues
rcu-tasks: Use workqueues for multiple rcu_tasks_invoke_cbs() invocations
rcu-tasks: Abstract invocations of callbacks
rcu-tasks: Abstract checking of callback lists
rcu-tasks: Add a ->percpu_enqueue_lim to the rcu_tasks structure
rcu-tasks: Inspect stalled task's trc state in locked state
rcu-tasks: Use spin_lock_rcu_node() and friends
rcutorture: Combine n_max_cbs from all kthreads in a callback flood
...
Pull printk updates from Petr Mladek:
- Remove some twists in the console registration code. It does not
change the existing behavior except for one corner case. The proper
default console (with tty binding) will be registered again even when
it has been removed in the meantime. It is actually a bug fix.
Anyway, this modified behavior requires some manual interaction.
- Optimize gdb extension for huge ring buffers.
- Do not use atomic operations for a local bitmap variable.
- Update git links in MAINTAINERS.
* tag 'printk-for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/printk/linux:
MAINTAIERS/printk: Add link to printk git
MAINTAINERS/vsprintf: Update link to printk git tree
scripts/gdb: lx-dmesg: read records individually
printk/console: Clean up boot console handling in register_console()
printk/console: Remove need_default_console variable
printk/console: Remove unnecessary need_default_console manipulation
printk/console: Rename has_preferred_console to need_default_console
printk/console: Split out code that enables default console
vsprintf: Use non-atomic bitmap API when applicable
Pull workqueue updates from Tejun Heo:
- The code around workqueue scheduler hooks got reorganized early 2019
which unfortuately introdued a couple subtle and rare race conditions
where preemption can mangle internal workqueue state triggering a
WARN and possibly causing a stall or at least delay in execution.
Frederic fixed both early December and the fixes were sitting in
for-5.16-fixes which I forgot to push. They are here now. I'll
forward them to stable after they land.
- The scheduler hook reorganization has more implicatoins for workqueue
code in that the hooks are now more strictly synchronized and thus
the interacting operations can become more straight-forward.
Lai is in the process of simplifying workqueue code and this pull
request contains some of the patches.
* 'for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq:
workqueue: Remove the cacheline_aligned for nr_running
workqueue: Move the code of waking a worker up in unbind_workers()
workqueue: Remove schedule() in unbind_workers()
workqueue: Remove outdated comment about exceptional workers in unbind_workers()
workqueue: Remove the advanced kicking of the idle workers in rebind_workers()
workqueue: Remove the outdated comment before wq_worker_sleeping()
workqueue: Fix unbind_workers() VS wq_worker_sleeping() race
workqueue: Fix unbind_workers() VS wq_worker_running() race
workqueue: Upgrade queue_work_on() comment
Pull cgroup updates from Tejun Heo:
"Nothing too interesting. The only two noticeable changes are a subtle
cpuset behavior fix and trace event id field being expanded to u64
from int. Most others are code cleanups"
* 'for-5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup:
cpuset: convert 'allowed' in __cpuset_node_allowed() to be boolean
cgroup/rstat: check updated_next only for root
cgroup: rstat: explicitly put loop variant in while
cgroup: return early if it is already on preloaded list
cgroup/cpuset: Don't let child cpusets restrict parent in default hierarchy
cgroup: Trace event cgroup id fields should be u64
cgroup: fix a typo in comment
cgroup: get the wrong css for css_alloc() during cgroup_init_subsys()
cgroup: rstat: Mark benign data race to silence KCSAN
