Commit Graph

49150 Commits

Author SHA1 Message Date
Chen Ridong
c198b19552 cpuset: Use new excpus for nocpu error check when enabling root partition
[ Upstream commit 59d5de3655698679ad8fd2cc82228de4679c4263 ]

A previous patch fixed a bug where new_prs should be assigned before
checking housekeeping conflicts. This patch addresses another potential
issue: the nocpu error check currently uses the xcpus which is not updated.
Although no issue has been observed so far, the check should be performed
using the new effective exclusive cpus.

The comment has been removed because the function returns an error if
nocpu checking fails, which is unrelated to the parent.

Signed-off-by: Chen Ridong <chenridong@huawei.com>
Reviewed-by: Waiman Long <longman@redhat.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:04 +09:00
Tejun Heo
09a75f3712 sched_ext: Keep bypass on between enable failure and scx_disable_workfn()
[ Upstream commit 4a1d9d73aabc8f97f48c4f84f936de3b265ffd6f ]

scx_enable() turns on the bypass mode while enable is in progress. If
enabling fails, it turns off the bypass mode and then triggers scx_error().
scx_error() will trigger scx_disable_workfn() which will turn on the bypass
mode again and unload the failed scheduler.

This moves the system out of bypass mode between the enable error path and
the disable path, which is unnecessary and can be brittle - e.g. the thread
running scx_enable() may already be on the failed scheduler and can be
switched out before it triggers scx_error() leading to a stall. The watchdog
would eventually kick in, so the situation isn't critical but is still
suboptimal.

There is nothing to be gained by turning off the bypass mode between
scx_enable() failure and scx_disable_workfn(). Keep bypass on.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Jiri Olsa
b7d8670766 seccomp: passthrough uprobe systemcall without filtering
[ Upstream commit 89d1d8434d246c96309a6068dfcf9e36dc61227b ]

Adding uprobe as another exception to the seccomp filter alongside
with the uretprobe syscall.

Same as the uretprobe the uprobe syscall is installed by kernel as
replacement for the breakpoint exception and is limited to x86_64
arch and isn't expected to ever be supported in i386.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://lore.kernel.org/r/20250720112133.244369-21-jolsa@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Josh Poimboeuf
02b3654ea8 perf: Skip user unwind if the task is a kernel thread
[ Upstream commit 16ed389227651330879e17bd83d43bd234006722 ]

If the task is not a user thread, there's no user stack to unwind.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250820180428.930791978@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Josh Poimboeuf
10f41e2a8f perf: Have get_perf_callchain() return NULL if crosstask and user are set
[ Upstream commit 153f9e74dec230f2e070e16fa061bc7adfd2c450 ]

get_perf_callchain() doesn't support cross-task unwinding for user space
stacks, have it return NULL if both the crosstask and user arguments are
set.

Signed-off-by: Josh Poimboeuf <jpoimboe@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250820180428.426423415@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Steven Rostedt
5050083e1a perf: Use current->flags & PF_KTHREAD|PF_USER_WORKER instead of current->mm == NULL
[ Upstream commit 90942f9fac05702065ff82ed0bade0d08168d4ea ]

To determine if a task is a kernel thread or not, it is more reliable to
use (current->flags & (PF_KTHREAD|PF_USER_WORKERi)) than to rely on
current->mm being NULL.  That is because some kernel tasks (io_uring
helpers) may have a mm field.

Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20250820180428.592367294@kernel.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Charles Keepax
f1971d5ba2 genirq/manage: Add buslock back in to enable_irq()
[ Upstream commit ef3330b99c01bda53f2a189b58bed8f6b7397f28 ]

The locking was changed from a buslock to a plain lock, but the patch
description states there was no functional change. Assuming this was
accidental so reverting to using the buslock.

Fixes: bddd10c554 ("genirq/manage: Rework enable_irq()")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251023154901.1333755-4-ckeepax@opensource.cirrus.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Charles Keepax
b990b4c6ea genirq/manage: Add buslock back in to __disable_irq_nosync()
[ Upstream commit 56363e25f79fe83e63039c5595b8cd9814173d37 ]

The locking was changed from a buslock to a plain lock, but the patch
description states there was no functional change. Assuming this was
accidental so reverting to using the buslock.

Fixes: 1b74444467 ("genirq/manage: Rework __disable_irq_nosync()")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251023154901.1333755-3-ckeepax@opensource.cirrus.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Charles Keepax
3c97437239 genirq/chip: Add buslock back in to irq_set_handler()
[ Upstream commit 5d7e45dd670e42df4836afeaa9baf9d41ca4b434 ]

The locking was changed from a buslock to a plain lock, but the patch
description states there was no functional change. Assuming this was
accidental so reverting to using the buslock.

Fixes: 5cd05f3e23 ("genirq/chip: Rework irq_set_handler() variants")
Signed-off-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/20251023154901.1333755-2-ckeepax@opensource.cirrus.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:03 +09:00
Haofeng Li
66178a7bdd timekeeping: Fix aux clocks sysfs initialization loop bound
[ Upstream commit 39a9ed0fb6dac58547afdf9b6cb032d326a3698f ]

The loop in tk_aux_sysfs_init() uses `i <= MAX_AUX_CLOCKS` as the
termination condition, which results in 9 iterations (i=0 to 8) when
MAX_AUX_CLOCKS is defined as 8. However, the kernel is designed to support
only up to 8 auxiliary clocks.

This off-by-one error causes the creation of a 9th sysfs entry that exceeds
the intended auxiliary clock range.

Fix the loop bound to use `i < MAX_AUX_CLOCKS` to ensure exactly 8
auxiliary clock entries are created, matching the design specification.

Fixes: 7b95663a3d ("timekeeping: Provide interface to control auxiliary clocks")
Signed-off-by: Haofeng Li <lihaofeng@kylinos.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://patch.msgid.link/tencent_2376993D9FC06A3616A4F981B3DE1C599607@qq.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:02 +09:00
Tejun Heo
60407ac172 sched_ext: Sync error_irq_work before freeing scx_sched
[ Upstream commit efeeaac9ae9763f9c953e69633c86bc3031e39b5 ]

By the time scx_sched_free_rcu_work() runs, the scx_sched is no longer
reachable. However, a previously queued error_irq_work may still be pending or
running. Ensure it completes before proceeding with teardown.

Fixes: bff3b5aec1 ("sched_ext: Move disable machinery into scx_sched")
Acked-by: Andrea Righi <arighi@nvidia.com>
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:02 +09:00
Tejun Heo
733d0e1184 sched_ext: Put event_stats_cpu in struct scx_sched_pcpu
[ Upstream commit bcb7c2305682c77a8bfdbfe37106b314ac10110f ]

scx_sched.event_stats_cpu is the percpu counters that are used to track
stats. Introduce struct scx_sched_pcpu and move the counters inside. This
will ease adding more per-cpu fields. No functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Andrea Righi <arighi@nvidia.com>
Stable-dep-of: efeeaac9ae97 ("sched_ext: Sync error_irq_work before freeing scx_sched")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:02 +09:00
Tejun Heo
2efd07e290 sched_ext: Move internal type and accessor definitions to ext_internal.h
[ Upstream commit 0c2b8356e430229efef42b03bd765a2a7ecf73fd ]

There currently isn't a place to place SCX-internal types and accessors to
be shared between ext.c and ext_idle.c. Create kernel/sched/ext_internal.h
and move internal type and accessor definitions there. This trims ext.c a
bit and makes future additions easier. Pure code reorganization. No
functional changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Acked-by: Andrea Righi <arighi@nvidia.com>
Stable-dep-of: efeeaac9ae97 ("sched_ext: Sync error_irq_work before freeing scx_sched")
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-11-02 22:18:02 +09:00
Andy Shevchenko
5975ce4a02 sched: Remove never used code in mm_cid_get()
[ Upstream commit 53abe3e1c154628cc74e33a1bfcd865656e433a5 ]

Clang is not happy with set but unused variable (this is visible
with `make W=1` build:

  kernel/sched/sched.h:3744:18: error: variable 'cpumask' set but not used [-Werror,-Wunused-but-set-variable]

It seems like the variable was never used along with the assignment
that does not have side effects as far as I can see.  Remove those
altogether.

Fixes: 223baf9d17 ("sched: Fix performance regression introduced by mm_cid")
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Tested-by: Eric Biggers <ebiggers@kernel.org>
Reviewed-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-29 14:10:29 +01:00
Nam Cao
ef6fb1fff2 rv: Make rtapp/pagefault monitor depends on CONFIG_MMU
commit 3d62f95bd8450cebb4a4741bf83949cd54edd4a3 upstream.

There is no page fault without MMU. Compiling the rtapp/pagefault monitor
without CONFIG_MMU fails as page fault tracepoints' definitions are not
available.

Make rtapp/pagefault monitor depends on CONFIG_MMU.

Fixes: 9162620eb6 ("rv: Add rtapp_pagefault monitor")
Signed-off-by: Nam Cao <namcao@linutronix.de>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/oe-kbuild-all/202509260455.6Z9Vkty4-lkp@intel.com/
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/r/20251002082317.973839-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-29 14:10:23 +01:00
Nam Cao
8948a0338d rv: Fully convert enabled_monitors to use list_head as iterator
commit 103541e6a5854b08a25e4caa61e990af1009a52e upstream.

The callbacks in enabled_monitors_seq_ops are inconsistent. Some treat the
iterator as struct rv_monitor *, while others treat the iterator as struct
list_head *.

This causes a wrong type cast and crashes the system as reported by Nathan.

Convert everything to use struct list_head * as iterator. This also makes
enabled_monitors consistent with available_monitors.

Fixes: de090d1cca ("rv: Fix wrong type cast in enabled_monitors_next()")
Reported-by: Nathan Chancellor <nathan@kernel.org>
Closes: https://lore.kernel.org/linux-trace-kernel/20250923002004.GA2836051@ax162/
Signed-off-by: Nam Cao <namcao@linutronix.de>
Cc: stable@vger.kernel.org
Reviewed-by: Gabriele Monaco <gmonaco@redhat.com>
Link: https://lore.kernel.org/r/20251002082235.973099-1-namcao@linutronix.de
Signed-off-by: Gabriele Monaco <gmonaco@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-29 14:10:23 +01:00
Marek Szyprowski
f784c10c51 dma-debug: don't report false positives with DMA_BOUNCE_UNALIGNED_KMALLOC
commit 03521c892bb8d0712c23e158ae9bdf8705897df8 upstream.

Commit 370645f41e ("dma-mapping: force bouncing if the kmalloc() size is
not cache-line-aligned") introduced DMA_BOUNCE_UNALIGNED_KMALLOC feature
and permitted architecture specific code configure kmalloc slabs with
sizes smaller than the value of dma_get_cache_alignment().

When that feature is enabled, the physical address of some small
kmalloc()-ed buffers might be not aligned to the CPU cachelines, thus not
really suitable for typical DMA.  To properly handle that case a SWIOTLB
buffer bouncing is used, so no CPU cache corruption occurs.  When that
happens, there is no point reporting a false-positive DMA-API warning that
the buffer is not properly aligned, as this is not a client driver fault.

[m.szyprowski@samsung.com: replace is_swiotlb_allocated() with is_swiotlb_active(), per Catalin]
  Link: https://lkml.kernel.org/r/20251010173009.3916215-1-m.szyprowski@samsung.com
Link: https://lkml.kernel.org/r/20251009141508.2342138-1-m.szyprowski@samsung.com
Fixes: 370645f41e ("dma-mapping: force bouncing if the kmalloc() size is not cache-line-aligned")
Signed-off-by: Marek Szyprowski <m.szyprowski@samsung.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Inki Dae <m.szyprowski@samsung.com>
Cc: Robin Murohy <robin.murphy@arm.com>
Cc: "Isaac J. Manjarres" <isaacmanjarres@google.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-29 14:10:21 +01:00
K Prateek Nayak
514784d008 sched/fair: Block delayed tasks on throttled hierarchy during dequeue
Dequeuing a fair task on a throttled hierarchy returns early on
encountering a throttled cfs_rq since the throttle path has already
dequeued the hierarchy above and has adjusted the h_nr_* accounting till
the root cfs_rq.

dequeue_entities() crucially misses calling __block_task() for delayed
tasks being dequeued on the throttled hierarchies, but this was mostly
harmless until commit b7ca5743a2 ("sched/core: Tweak
wait_task_inactive() to force dequeue sched_delayed tasks") since all
existing cases would re-enqueue the task if task_on_rq_queued() returned
true and the task would eventually be blocked at pick after the
hierarchy was unthrottled.

wait_task_inactive() is special as it expects the delayed task on
throttled hierarchy to reach the blocked state on dequeue but since
__block_task() is never called, task_on_rq_queued() continues to return
true. Furthermore, since the task is now off the hierarchy, the pick
never reaches it to fully block the task even after unthrottle leading
to wait_task_inactive() looping endlessly.

Remedy this by calling __block_task() if a delayed task is being
dequeued on a throttled hierarchy.

This fix is only required for stabled kernels implementing delay dequeue
(>= v6.12) before v6.18 since upstream commit e1fad12dcb66 ("sched/fair:
Switch to task based throttle model") indirectly fixes this by removing
the early return conditions in dequeue_entities() as part of the per-task
throttle feature.

Cc: stable@vger.kernel.org
Reported-by: Matt Fleming <matt@readmodwrite.com>
Closes: https://lore.kernel.org/all/20250925133310.1843863-1-matt@readmodwrite.com/
Fixes: b7ca5743a2 ("sched/core: Tweak wait_task_inactive() to force dequeue sched_delayed tasks")
Tested-by: Matt Fleming <mfleming@cloudflare.com>
Signed-off-by: K Prateek Nayak <kprateek.nayak@amd.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-29 14:10:15 +01:00
Vincent Guittot
13aeb56dae sched/fair: Fix pelt lost idle time detection
[ Upstream commit 17e3e88ed0b6318fde0d1c14df1a804711cab1b5 ]

The check for some lost idle pelt time should be always done when
pick_next_task_fair() fails to pick a task and not only when we call it
from the fair fast-path.

The case happens when the last running task on rq is a RT or DL task. When
the latter goes to sleep and the /Sum of util_sum of the rq is at the max
value, we don't account the lost of idle time whereas we should.

Fixes: 67692435c4 ("sched: Rework pick_next_task() slow-path")
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-23 16:24:35 +02:00
Peter Zijlstra (Intel)
ab6c0f1585 sched/deadline: Stop dl_server before CPU goes offline
[ Upstream commit ee6e44dfe6e50b4a5df853d933a96bdff5309e6e ]

IBM CI tool reported kernel warning[1] when running a CPU removal
operation through drmgr[2]. i.e "drmgr -c cpu -r -q 1"

WARNING: CPU: 0 PID: 0 at kernel/sched/cpudeadline.c:219 cpudl_set+0x58/0x170
NIP [c0000000002b6ed8] cpudl_set+0x58/0x170
LR [c0000000002b7cb8] dl_server_timer+0x168/0x2a0
Call Trace:
[c000000002c2f8c0] init_stack+0x78c0/0x8000 (unreliable)
[c0000000002b7cb8] dl_server_timer+0x168/0x2a0
[c00000000034df84] __hrtimer_run_queues+0x1a4/0x390
[c00000000034f624] hrtimer_interrupt+0x124/0x300
[c00000000002a230] timer_interrupt+0x140/0x320

Git bisects to: commit 4ae8d9aa9f ("sched/deadline: Fix dl_server getting stuck")

This happens since:
- dl_server hrtimer gets enqueued close to cpu offline, when
  kthread_park enqueues a fair task.
- CPU goes offline and drmgr removes it from cpu_present_mask.
- hrtimer fires and warning is hit.

Fix it by stopping the dl_server before CPU is marked dead.

[1]: https://lore.kernel.org/all/8218e149-7718-4432-9312-f97297c352b9@linux.ibm.com/
[2]: https://github.com/ibm-power-utilities/powerpc-utils/tree/next/src/drmgr

[sshegde: wrote the changelog and tested it]
Fixes: 4ae8d9aa9f ("sched/deadline: Fix dl_server getting stuck")
Closes: https://lore.kernel.org/all/8218e149-7718-4432-9312-f97297c352b9@linux.ibm.com
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com>
Signed-off-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Shrikanth Hegde <sshegde@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-23 16:24:35 +02:00
Mario Limonciello (AMD)
cc431d9039 PM: hibernate: Add pm_hibernation_mode_is_suspend()
[ Upstream commit 495c8d35035edb66e3284113bef01f3b1b843832 ]

Some drivers have different flows for hibernation and suspend. If
the driver opportunistically will skip thaw() then it needs a hint
to know what is happening after the hibernate.

Introduce a new symbol pm_hibernation_mode_is_suspend() that drivers
can call to determine if suspending the system for this purpose.

Tested-by: Ionut Nechita <ionut_n2001@yahoo.com>
Tested-by: Kenneth Crudup <kenny@panix.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Stable-dep-of: 0a6e9e098fcc ("drm/amd: Fix hybrid sleep")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-23 16:24:26 +02:00
Adrian Hunter
66a9ce8f67 perf/core: Fix MMAP2 event device with backing files
commit fa4f4bae893fbce8a3edfff1ab7ece0c01dc1328 upstream.

Some file systems like FUSE-based ones or overlayfs may record the backing
file in struct vm_area_struct vm_file, instead of the user file that the
user mmapped.

That causes perf to misreport the device major/minor numbers of the file
system of the file, and the generation of the file, and potentially other
inode details.  There is an existing helper file_user_inode() for that
situation.

Use file_user_inode() instead of file_inode() to get the inode for MMAP2
events.

Example:

  Setup:

    # cd /root
    # mkdir test ; cd test ; mkdir lower upper work merged
    # cp `which cat` lower
    # mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir=work merged
    # perf record -e cycles:u -- /root/test/merged/cat /proc/self/maps
    ...
    55b2c91d0000-55b2c926b000 r-xp 00018000 00:1a 3419                       /root/test/merged/cat
    ...
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.004 MB perf.data (5 samples) ]
    #
    # stat /root/test/merged/cat
      File: /root/test/merged/cat
      Size: 1127792         Blocks: 2208       IO Block: 4096   regular file
    Device: 0,26    Inode: 3419        Links: 1
    Access: (0755/-rwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
    Access: 2025-09-08 12:23:59.453309624 +0000
    Modify: 2025-09-08 12:23:59.454309624 +0000
    Change: 2025-09-08 12:23:59.454309624 +0000
     Birth: 2025-09-08 12:23:59.453309624 +0000

  Before:

    Device reported 00:02 differs from stat output and /proc/self/maps

    # perf script --show-mmap-events | grep /root/test/merged/cat
             cat     377 [-01]   243.078558: PERF_RECORD_MMAP2 377/377: [0x55b2c91d0000(0x9b000) @ 0x18000 00:02 3419 2068525940]: r-xp /root/test/merged/cat

  After:

    Device reported 00:1a is the same as stat output and /proc/self/maps

    # perf script --show-mmap-events | grep /root/test/merged/cat
             cat     362 [-01]   127.755167: PERF_RECORD_MMAP2 362/362: [0x55ba6e781000(0x9b000) @ 0x18000 00:1a 3419 0]: r-xp /root/test/merged/cat

With respect to stable kernels, overlayfs mmap function ovl_mmap() was
added in v4.19 but file_user_inode() was not added until v6.8 and never
back-ported to stable kernels.  FMODE_BACKING that it depends on was added
in v6.5.  This issue has gone largely unnoticed, so back-porting before
v6.8 is probably not worth it, so put 6.8 as the stable kernel prerequisite
version, although in practice the next long term kernel is 6.12.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Amir Goldstein <amir73il@gmail.com>
Cc: stable@vger.kernel.org # 6.8
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-23 16:24:26 +02:00
Adrian Hunter
a1d4eb2dbb perf/core: Fix MMAP event path names with backing files
commit 8818f507a9391019a3ec7c57b1a32e4b386e48a5 upstream.

Some file systems like FUSE-based ones or overlayfs may record the backing
file in struct vm_area_struct vm_file, instead of the user file that the
user mmapped.

Since commit def3ae83da ("fs: store real path instead of fake path in
backing file f_path"), file_path() no longer returns the user file path
when applied to a backing file.  There is an existing helper
file_user_path() for that situation.

Use file_user_path() instead of file_path() to get the path for MMAP
and MMAP2 events.

Example:

  Setup:

    # cd /root
    # mkdir test ; cd test ; mkdir lower upper work merged
    # cp `which cat` lower
    # mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir=work merged
    # perf record -e intel_pt//u -- /root/test/merged/cat /proc/self/maps
    ...
    55b0ba399000-55b0ba434000 r-xp 00018000 00:1a 3419                       /root/test/merged/cat
    ...
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.060 MB perf.data ]
    #

  Before:

    File name is wrong (/cat), so decoding fails:

    # perf script --no-itrace --show-mmap-events
             cat     367 [016]   100.491492: PERF_RECORD_MMAP2 367/367: [0x55b0ba399000(0x9b000) @ 0x18000 00:02 3419 489959280]: r-xp /cat
    ...
    # perf script --itrace=e | wc -l
    Warning:
    19 instruction trace errors
    19
    #

  After:

    File name is correct (/root/test/merged/cat), so decoding is ok:

    # perf script --no-itrace --show-mmap-events
                 cat     364 [016]    72.153006: PERF_RECORD_MMAP2 364/364: [0x55ce4003d000(0x9b000) @ 0x18000 00:02 3419 3132534314]: r-xp /root/test/merged/cat
    # perf script --itrace=e
    # perf script --itrace=e | wc -l
    0
    #

Fixes: def3ae83da ("fs: store real path instead of fake path in backing file f_path")
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Amir Goldstein <amir73il@gmail.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-23 16:24:25 +02:00
Adrian Hunter
ad67f97b8b perf/core: Fix address filter match with backing files
commit ebfc8542ad62d066771e46c8aa30f5624b89cad8 upstream.

It was reported that Intel PT address filters do not work in Docker
containers.  That relates to the use of overlayfs.

overlayfs records the backing file in struct vm_area_struct vm_file,
instead of the user file that the user mmapped.  In order for an address
filter to match, it must compare to the user file inode.  There is an
existing helper file_user_inode() for that situation.

Use file_user_inode() instead of file_inode() to get the inode for address
filter matching.

Example:

  Setup:

    # cd /root
    # mkdir test ; cd test ; mkdir lower upper work merged
    # cp `which cat` lower
    # mount -t overlay overlay -olowerdir=lower,upperdir=upper,workdir=work merged
    # perf record --buildid-mmap -e intel_pt//u --filter 'filter * @ /root/test/merged/cat' -- /root/test/merged/cat /proc/self/maps
    ...
    55d61d246000-55d61d2e1000 r-xp 00018000 00:1a 3418                       /root/test/merged/cat
    ...
    [ perf record: Woken up 1 times to write data ]
    [ perf record: Captured and wrote 0.015 MB perf.data ]
    # perf buildid-cache --add /root/test/merged/cat

  Before:

    Address filter does not match so there are no control flow packets

    # perf script --itrace=e
    # perf script --itrace=b | wc -l
    0
    # perf script -D | grep 'TIP.PGE' | wc -l
    0
    #

  After:

    Address filter does match so there are control flow packets

    # perf script --itrace=e
    # perf script --itrace=b | wc -l
    235
    # perf script -D | grep 'TIP.PGE' | wc -l
    57
    #

With respect to stable kernels, overlayfs mmap function ovl_mmap() was
added in v4.19 but file_user_inode() was not added until v6.8 and never
back-ported to stable kernels.  FMODE_BACKING that it depends on was added
in v6.5.  This issue has gone largely unnoticed, so back-porting before
v6.8 is probably not worth it, so put 6.8 as the stable kernel prerequisite
version, although in practice the next long term kernel is 6.12.

Closes: https://lore.kernel.org/linux-perf-users/aBCwoq7w8ohBRQCh@fremen.lan
Reported-by: Edd Barrett <edd@theunixzoo.co.uk>
Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Amir Goldstein <amir73il@gmail.com>
Cc: stable@vger.kernel.org # 6.8
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-23 16:24:25 +02:00
gaoxiang17
a0212978af pid: Add a judgment for ns null in pid_nr_ns
[ Upstream commit 006568ab4c5ca2309ceb36fa553e390b4aa9c0c7 ]

__task_pid_nr_ns
        ns = task_active_pid_ns(current);
        pid_nr_ns(rcu_dereference(*task_pid_ptr(task, type)), ns);
                if (pid && ns->level <= pid->level) {

Sometimes null is returned for task_active_pid_ns. Then it will trigger kernel panic in pid_nr_ns.

For example:
	Unable to handle kernel NULL pointer dereference at virtual address 0000000000000058
	Mem abort info:
	ESR = 0x0000000096000007
	EC = 0x25: DABT (current EL), IL = 32 bits
	SET = 0, FnV = 0
	EA = 0, S1PTW = 0
	FSC = 0x07: level 3 translation fault
	Data abort info:
	ISV = 0, ISS = 0x00000007, ISS2 = 0x00000000
	CM = 0, WnR = 0, TnD = 0, TagAccess = 0
	GCS = 0, Overlay = 0, DirtyBit = 0, Xs = 0
	user pgtable: 4k pages, 39-bit VAs, pgdp=00000002175aa000
	[0000000000000058] pgd=08000002175ab003, p4d=08000002175ab003, pud=08000002175ab003, pmd=08000002175be003, pte=0000000000000000
	pstate: 834000c5 (Nzcv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
	pc : __task_pid_nr_ns+0x74/0xd0
	lr : __task_pid_nr_ns+0x24/0xd0
	sp : ffffffc08001bd10
	x29: ffffffc08001bd10 x28: ffffffd4422b2000 x27: 0000000000000001
	x26: ffffffd442821168 x25: ffffffd442821000 x24: 00000f89492eab31
	x23: 00000000000000c0 x22: ffffff806f5693c0 x21: ffffff806f5693c0
	x20: 0000000000000001 x19: 0000000000000000 x18: 0000000000000000
	x17: 00000000529c6ef0 x16: 00000000529c6ef0 x15: 00000000023a1adc
	x14: 0000000000000003 x13: 00000000007ef6d8 x12: 001167c391c78800
	x11: 00ffffffffffffff x10: 0000000000000000 x9 : 0000000000000001
	x8 : ffffff80816fa3c0 x7 : 0000000000000000 x6 : 49534d702d535449
	x5 : ffffffc080c4c2c0 x4 : ffffffd43ee128c8 x3 : ffffffd43ee124dc
	x2 : 0000000000000000 x1 : 0000000000000001 x0 : ffffff806f5693c0
	Call trace:
	__task_pid_nr_ns+0x74/0xd0
	...
	__handle_irq_event_percpu+0xd4/0x284
	handle_irq_event+0x48/0xb0
	handle_fasteoi_irq+0x160/0x2d8
	generic_handle_domain_irq+0x44/0x60
	gic_handle_irq+0x4c/0x114
	call_on_irq_stack+0x3c/0x74
	do_interrupt_handler+0x4c/0x84
	el1_interrupt+0x34/0x58
	el1h_64_irq_handler+0x18/0x24
	el1h_64_irq+0x68/0x6c
	account_kernel_stack+0x60/0x144
	exit_task_stack_account+0x1c/0x80
	do_exit+0x7e4/0xaf8
	...
	get_signal+0x7bc/0x8d8
	do_notify_resume+0x128/0x828
	el0_svc+0x6c/0x70
	el0t_64_sync_handler+0x68/0xbc
	el0t_64_sync+0x1a8/0x1ac
	Code: 35fffe54 911a02a8 f9400108 b4000128 (b9405a69)
	---[ end trace 0000000000000000 ]---
	Kernel panic - not syncing: Oops: Fatal exception in interrupt

Signed-off-by: gaoxiang17 <gaoxiang17@xiaomi.com>
Link: https://lore.kernel.org/20250802022123.3536934-1-gxxa03070307@gmail.com
Reviewed-by: Baoquan He <bhe@redhat.com>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-19 16:37:43 +02:00
Harshit Agarwal
c8e5a86acf sched/deadline: Fix race in push_dl_task()
commit 8fd5485fb4f3d9da3977fd783fcb8e5452463420 upstream.

When a CPU chooses to call push_dl_task and picks a task to push to
another CPU's runqueue then it will call find_lock_later_rq method
which would take a double lock on both CPUs' runqueues. If one of the
locks aren't readily available, it may lead to dropping the current
runqueue lock and reacquiring both the locks at once. During this window
it is possible that the task is already migrated and is running on some
other CPU. These cases are already handled. However, if the task is
migrated and has already been executed and another CPU is now trying to
wake it up (ttwu) such that it is queued again on the runqeue
(on_rq is 1) and also if the task was run by the same CPU, then the
current checks will pass even though the task was migrated out and is no
longer in the pushable tasks list.
Please go through the original rt change for more details on the issue.

To fix this, after the lock is obtained inside the find_lock_later_rq,
it ensures that the task is still at the head of pushable tasks list.
Also removed some checks that are no longer needed with the addition of
this new check.
However, the new check of pushable tasks list only applies when
find_lock_later_rq is called by push_dl_task. For the other caller i.e.
dl_task_offline_migration, existing checks are used.

Signed-off-by: Harshit Agarwal <harshit@nutanix.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Juri Lelli <juri.lelli@redhat.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20250408045021.3283624-1-harshit@nutanix.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:30 +02:00
Rafael J. Wysocki
17b6b78171 PM: hibernate: Restrict GFP mask in power_down()
commit 6f4c6f9ed4ce65303f6bb153e2afc71bc33c8ded upstream.

Commit 12ffc3b151 ("PM: Restrict swap use to later in the
suspend sequence") caused hibernation_platform_enter() to call
pm_restore_gfp_mask() via dpm_resume_end(), so when power_down()
returns after aborting hibernation_platform_enter(), it needs
to match the pm_restore_gfp_mask() call in hibernate() that will
occur subsequently.

Address this by adding a pm_restrict_gfp_mask() call to the relevant
error path in power_down().

Fixes: 12ffc3b151 ("PM: Restrict swap use to later in the suspend sequence")
Cc: 6.16+ <stable@vger.kernel.org> # 6.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Reviewed-by: Mario Limonciello (AMD) <superm1@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:29 +02:00
Mario Limonciello (AMD)
7425ca69f3 PM: hibernate: Fix hybrid-sleep
commit 469d80a3712c66a00b5bb888e62e809db8887ba7 upstream.

Hybrid sleep will hibernate the system followed by running through
the suspend routine.  Since both the hibernate and the suspend routine
will call pm_restrict_gfp_mask(), pm_restore_gfp_mask() must be called
before starting the suspend sequence.

Add an explicit call to pm_restore_gfp_mask() to power_down() before
the suspend sequence starts. Add an extra call for pm_restrict_gfp_mask()
when exiting suspend so that the pm_restore_gfp_mask() call in hibernate()
is balanced.

Reported-by: Ionut Nechita <ionut_n2001@yahoo.com>
Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4573
Tested-by: Ionut Nechita <ionut_n2001@yahoo.com>
Fixes: 12ffc3b151 ("PM: Restrict swap use to later in the suspend sequence")
Tested-by: Kenneth Crudup <kenny@panix.com>
Acked-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Mario Limonciello (AMD) <superm1@kernel.org>
Link: https://patch.msgid.link/20250925185108.2968494-2-superm1@kernel.org
[ rjw: Add comment explainig the new pm_restrict_gfp_mask() call purpose ]
Cc: 6.16+ <stable@vger.kernel.org> # 6.16+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:29 +02:00
Christian Loehle
cdbebde875 PM: EM: Fix late boot with holes in CPU topology
commit 1ebe8f7e782523e62cd1fa8237f7afba5d1dae83 upstream.

Commit e3f1164fc9 ("PM: EM: Support late CPUs booting and capacity
adjustment") added a mechanism to handle CPUs that come up late by
retrying when any of the `cpufreq_cpu_get()` call fails.

However, if there are holes in the CPU topology (offline CPUs, e.g.
nosmt), the first missing CPU causes the loop to break, preventing
subsequent online CPUs from being updated.

Instead of aborting on the first missing CPU policy, loop through all
and retry if any were missing.

Fixes: e3f1164fc9 ("PM: EM: Support late CPUs booting and capacity adjustment")
Suggested-by: Kenneth Crudup <kenneth.crudup@gmail.com>
Reported-by: Kenneth Crudup <kenneth.crudup@gmail.com>
Link: https://lore.kernel.org/linux-pm/40212796-734c-4140-8a85-854f72b8144d@panix.com/
Cc: 6.9+ <stable@vger.kernel.org> # 6.9+
Signed-off-by: Christian Loehle <christian.loehle@arm.com>
Link: https://patch.msgid.link/20250831214357.2020076-1-christian.loehle@arm.com
[ rjw: Drop the new pr_debug() message which is not very useful ]
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:29 +02:00
Xiao Liang
a68c1d4145 padata: Reset next CPU when reorder sequence wraps around
commit 501302d5cee0d8e8ec2c4a5919c37e0df9abc99b upstream.

When seq_nr wraps around, the next reorder job with seq 0 is hashed to
the first CPU in padata_do_serial(). Correspondingly, need reset pd->cpu
to the first one when pd->processed wraps around. Otherwise, if the
number of used CPUs is not a power of 2, padata_find_next() will be
checking a wrong list, hence deadlock.

Fixes: 6fc4dbcf02 ("padata: Replace delayed timer with immediate workqueue in padata_reorder")
Cc: <stable@vger.kernel.org>
Signed-off-by: Xiao Liang <shaw.leon@gmail.com>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:29 +02:00
Pratyush Yadav
8f4abe676e kho: only fill kimage if KHO is finalized
commit f322a97aeb2a05b6b1ee17629145eb02e1a4c6a0 upstream.

kho_fill_kimage() only checks for KHO being enabled before filling in the
FDT to the image.  KHO being enabled does not mean that the kernel has
data to hand over.  That happens when KHO is finalized.

When a kexec is done with KHO enabled but not finalized, the FDT page is
allocated but not initialized.  FDT initialization happens after finalize.
This means the KHO segment is filled in but the FDT contains garbage
data.

This leads to the below error messages in the next kernel:

    [    0.000000] KHO: setup: handover FDT (0x10116b000) is invalid: -9
    [    0.000000] KHO: disabling KHO revival: -22

There is no problem in practice, and the next kernel boots and works fine.
But this still leads to misleading error messages and garbage being
handed over.

Only fill in KHO segment when KHO is finalized.  When KHO is not enabled,
the debugfs interface is not created and there is no way to finalize it
anyway.  So the check for kho_enable is not needed, and kho_out.finalize
alone is enough.

Link: https://lkml.kernel.org/r/20250918170617.91413-1-pratyush@kernel.org
Fixes: 3bdecc3c93 ("kexec: add KHO support to kexec file loads")
Signed-off-by: Pratyush Yadav <pratyush@kernel.org>
Reviewed-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Alexander Graf <graf@amazon.com>
Cc: Baoquan He <bhe@redhat.com>
Cc: Changyuan Lyu <changyuanl@google.com>
Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Pasha Tatashin <pasha.tatashin@soleen.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:28 +02:00
Oleg Nesterov
6796412dec kernel/sys.c: fix the racy usage of task_lock(tsk->group_leader) in sys_prlimit64() paths
commit a15f37a40145c986cdf289a4b88390f35efdecc4 upstream.

The usage of task_lock(tsk->group_leader) in sys_prlimit64()->do_prlimit()
path is very broken.

sys_prlimit64() does get_task_struct(tsk) but this only protects task_struct
itself. If tsk != current and tsk is not a leader, this process can exit/exec
and task_lock(tsk->group_leader) may use the already freed task_struct.

Another problem is that sys_prlimit64() can race with mt-exec which changes
->group_leader. In this case do_prlimit() may take the wrong lock, or (worse)
->group_leader may change between task_lock() and task_unlock().

Change sys_prlimit64() to take tasklist_lock when necessary. This is not
nice, but I don't see a better fix for -stable.

Link: https://lkml.kernel.org/r/20250915120917.GA27702@redhat.com
Fixes: 18c91bb2d8 ("prlimit: do not grab the tasklist_lock")
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Mateusz Guzik <mjguzik@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:28 +02:00
Simon Schuster
b5db860132 copy_sighand: Handle architectures where sizeof(unsigned long) < sizeof(u64)
commit 04ff48239f46e8b493571e260bd0e6c3a6400371 upstream.

With the introduction of clone3 in commit 7f192e3cd3 ("fork: add
clone3") the effective bit width of clone_flags on all architectures was
increased from 32-bit to 64-bit. However, the signature of the copy_*
helper functions (e.g., copy_sighand) used by copy_process was not
adapted.

As such, they truncate the flags on any 32-bit architectures that
supports clone3 (arc, arm, csky, m68k, microblaze, mips32, openrisc,
parisc32, powerpc32, riscv32, x86-32 and xtensa).

For copy_sighand with CLONE_CLEAR_SIGHAND being an actual u64
constant, this triggers an observable bug in kernel selftest
clone3_clear_sighand:

        if (clone_flags & CLONE_CLEAR_SIGHAND)

in function copy_sighand within fork.c will always fail given:

        unsigned long /* == uint32_t */ clone_flags
        #define CLONE_CLEAR_SIGHAND 0x100000000ULL

This commit fixes the bug by always passing clone_flags to copy_sighand
via their declared u64 type, invariant of architecture-dependent integer
sizes.

Fixes: b612e5df45 ("clone3: add CLONE_CLEAR_SIGHAND")
Cc: stable@vger.kernel.org # linux-5.5+
Signed-off-by: Simon Schuster <schuster.simon@siemens-energy.com>
Link: https://lore.kernel.org/20250901-nios2-implement-clone3-v2-1-53fcf5577d57@siemens-energy.com
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:37:24 +02:00
KaFai Wan
de2d2baecc bpf: Avoid RCU context warning when unpinning htab with internal structs
[ Upstream commit 4f375ade6aa9f37fd72d7a78682f639772089eed ]

When unpinning a BPF hash table (htab or htab_lru) that contains internal
structures (timer, workqueue, or task_work) in its values, a BUG warning
is triggered:
 BUG: sleeping function called from invalid context at kernel/bpf/hashtab.c:244
 in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 14, name: ksoftirqd/0
 ...

The issue arises from the interaction between BPF object unpinning and
RCU callback mechanisms:
1. BPF object unpinning uses ->free_inode() which schedules cleanup via
   call_rcu(), deferring the actual freeing to an RCU callback that
   executes within the RCU_SOFTIRQ context.
2. During cleanup of hash tables containing internal structures,
   htab_map_free_internal_structs() is invoked, which includes
   cond_resched() or cond_resched_rcu() calls to yield the CPU during
   potentially long operations.

However, cond_resched() or cond_resched_rcu() cannot be safely called from
atomic RCU softirq context, leading to the BUG warning when attempting
to reschedule.

Fix this by changing from ->free_inode() to ->destroy_inode() and rename
bpf_free_inode() to bpf_destroy_inode() for BPF objects (prog, map, link).
This allows direct inode freeing without RCU callback scheduling,
avoiding the invalid context warning.

Reported-by: Le Chen <tom2cat@sjtu.edu.cn>
Closes: https://lore.kernel.org/all/1444123482.1827743.1750996347470.JavaMail.zimbra@sjtu.edu.cn/
Fixes: 68134668c1 ("bpf: Add map side support for bpf timers.")
Suggested-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: KaFai Wan <kafai.wan@linux.dev>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Link: https://lore.kernel.org/r/20251008102628.808045-2-kafai.wan@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-19 16:37:15 +02:00
Thomas Gleixner
159e2db6cb rseq: Protect event mask against membarrier IPI
commit 6eb350a2233100a283f882c023e5ad426d0ed63b upstream.

rseq_need_restart() reads and clears task::rseq_event_mask with preemption
disabled to guard against the scheduler.

But membarrier() uses an IPI and sets the PREEMPT bit in the event mask
from the IPI, which leaves that RMW operation unprotected.

Use guard(irq) if CONFIG_MEMBARRIER is enabled to fix that.

Fixes: 2a36ab717e ("rseq/membarrier: Add MEMBARRIER_CMD_PRIVATE_EXPEDITED_RSEQ")
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Boqun Feng <boqun.feng@gmail.com>
Reviewed-by: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: stable@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-19 16:36:59 +02:00
Steven Rostedt
ecff148e9c tracing: Stop fortify-string from warning in tracing_mark_raw_write()
commit 54b91e54b113d4f15ab023a44f508251db6e22e7 upstream.

The way tracing_mark_raw_write() records its data is that it has the
following structure:

  struct {
	struct trace_entry;
	int id;
	char buf[];
  };

But memcpy(&entry->id, buf, size) triggers the following warning when the
size is greater than the id:

 ------------[ cut here ]------------
 memcpy: detected field-spanning write (size 6) of single field "&entry->id" at kernel/trace/trace.c:7458 (size 4)
 WARNING: CPU: 7 PID: 995 at kernel/trace/trace.c:7458 write_raw_marker_to_buffer.isra.0+0x1f9/0x2e0
 Modules linked in:
 CPU: 7 UID: 0 PID: 995 Comm: bash Not tainted 6.17.0-test-00007-g60b82183e78a-dirty #211 PREEMPT(voluntary)
 Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.17.0-debian-1.17.0-1 04/01/2014
 RIP: 0010:write_raw_marker_to_buffer.isra.0+0x1f9/0x2e0
 Code: 04 00 75 a7 b9 04 00 00 00 48 89 de 48 89 04 24 48 c7 c2 e0 b1 d1 b2 48 c7 c7 40 b2 d1 b2 c6 05 2d 88 6a 04 01 e8 f7 e8 bd ff <0f> 0b 48 8b 04 24 e9 76 ff ff ff 49 8d 7c 24 04 49 8d 5c 24 08 48
 RSP: 0018:ffff888104c3fc78 EFLAGS: 00010292
 RAX: 0000000000000000 RBX: 0000000000000006 RCX: 0000000000000000
 RDX: 0000000000000000 RSI: 1ffffffff6b363b4 RDI: 0000000000000001
 RBP: ffff888100058a00 R08: ffffffffb041d459 R09: ffffed1020987f40
 R10: 0000000000000007 R11: 0000000000000001 R12: ffff888100bb9010
 R13: 0000000000000000 R14: 00000000000003e3 R15: ffff888134800000
 FS:  00007fa61d286740(0000) GS:ffff888286cad000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000560d28d509f1 CR3: 00000001047a4006 CR4: 0000000000172ef0
 Call Trace:
  <TASK>
  tracing_mark_raw_write+0x1fe/0x290
  ? __pfx_tracing_mark_raw_write+0x10/0x10
  ? security_file_permission+0x50/0xf0
  ? rw_verify_area+0x6f/0x4b0
  vfs_write+0x1d8/0xdd0
  ? __pfx_vfs_write+0x10/0x10
  ? __pfx_css_rstat_updated+0x10/0x10
  ? count_memcg_events+0xd9/0x410
  ? fdget_pos+0x53/0x5e0
  ksys_write+0x182/0x200
  ? __pfx_ksys_write+0x10/0x10
  ? do_user_addr_fault+0x4af/0xa30
  do_syscall_64+0x63/0x350
  entry_SYSCALL_64_after_hwframe+0x76/0x7e
 RIP: 0033:0x7fa61d318687
 Code: 48 89 fa 4c 89 df e8 58 b3 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff
 RSP: 002b:00007ffd87fe0120 EFLAGS: 00000202 ORIG_RAX: 0000000000000001
 RAX: ffffffffffffffda RBX: 00007fa61d286740 RCX: 00007fa61d318687
 RDX: 0000000000000006 RSI: 0000560d28d509f0 RDI: 0000000000000001
 RBP: 0000560d28d509f0 R08: 0000000000000000 R09: 0000000000000000
 R10: 0000000000000000 R11: 0000000000000202 R12: 0000000000000006
 R13: 00007fa61d4715c0 R14: 00007fa61d46ee80 R15: 0000000000000000
  </TASK>
 ---[ end trace 0000000000000000 ]---

This is because fortify string sees that the size of entry->id is only 4
bytes, but it is writing more than that. But this is OK as the
dynamic_array is allocated to handle that copy.

The size allocated on the ring buffer was actually a bit too big:

  size = sizeof(*entry) + cnt;

But cnt includes the 'id' and the buffer data, so adding cnt to the size
of *entry actually allocates too much on the ring buffer.

Change the allocation to:

  size = struct_size(entry, buf, cnt - sizeof(entry->id));

and the memcpy() to unsafe_memcpy() with an added justification.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20251011112032.77be18e4@gandalf.local.home
Fixes: 64cf7d058a00 ("tracing: Have trace_marker use per-cpu data to read user space")
Reported-by: syzbot+9a2ede1643175f350105@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68e973f5.050a0220.1186a4.0010.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:18 +02:00
Steven Rostedt
48f3bf612e tracing: Fix tracing_mark_raw_write() to use buf and not ubuf
commit bda745ee8fbb63330d8f2f2ea4157229a5df959e upstream.

The fix to use a per CPU buffer to read user space tested only the writes
to trace_marker. But it appears that the selftests are missing tests to
the trace_maker_raw file. The trace_maker_raw file is used by applications
that writes data structures and not strings into the file, and the tools
read the raw ring buffer to process the structures it writes.

The fix that reads the per CPU buffers passes the new per CPU buffer to
the trace_marker file writes, but the update to the trace_marker_raw write
read the data from user space into the per CPU buffer, but then still used
then passed the user space address to the function that records the data.

Pass in the per CPU buffer and not the user space address.

TODO: Add a test to better test trace_marker_raw.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Link: https://lore.kernel.org/20251011035243.386098147@kernel.org
Fixes: 64cf7d058a00 ("tracing: Have trace_marker use per-cpu data to read user space")
Reported-by: syzbot+9a2ede1643175f350105@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/all/68e973f5.050a0220.1186a4.0010.GAE@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:18 +02:00
Steven Rostedt
3ceb52b70a tracing: Have trace_marker use per-cpu data to read user space
commit 64cf7d058a005c5c31eb8a0b741f35dc12915d18 upstream.

It was reported that using __copy_from_user_inatomic() can actually
schedule. Which is bad when preemption is disabled. Even though there's
logic to check in_atomic() is set, but this is a nop when the kernel is
configured with PREEMPT_NONE. This is due to page faulting and the code
could schedule with preemption disabled.

Link: https://lore.kernel.org/all/20250819105152.2766363-1-luogengkun@huaweicloud.com/

The solution was to change the __copy_from_user_inatomic() to
copy_from_user_nofault(). But then it was reported that this caused a
regression in Android. There's several applications writing into
trace_marker() in Android, but now instead of showing the expected data,
it is showing:

  tracing_mark_write: <faulted>

After reverting the conversion to copy_from_user_nofault(), Android was
able to get the data again.

Writes to the trace_marker is a way to efficiently and quickly enter data
into the Linux tracing buffer. It takes no locks and was designed to be as
non-intrusive as possible. This means it cannot allocate memory, and must
use pre-allocated data.

A method that is actively being worked on to have faultable system call
tracepoints read user space data is to allocate per CPU buffers, and use
them in the callback. The method uses a technique similar to seqcount.
That is something like this:

	preempt_disable();
	cpu = smp_processor_id();
	buffer = this_cpu_ptr(&pre_allocated_cpu_buffers, cpu);
	do {
		cnt = nr_context_switches_cpu(cpu);
		migrate_disable();
		preempt_enable();
		ret = copy_from_user(buffer, ptr, size);
		preempt_disable();
		migrate_enable();
	} while (!ret && cnt != nr_context_switches_cpu(cpu));

	if (!ret)
		ring_buffer_write(buffer);
	preempt_enable();

It's a little more involved than that, but the above is the basic logic.
The idea is to acquire the current CPU buffer, disable migration, and then
enable preemption. At this moment, it can safely use copy_from_user().
After reading the data from user space, it disables preemption again. It
then checks to see if there was any new scheduling on this CPU. If there
was, it must assume that the buffer was corrupted by another task. If
there wasn't, then the buffer is still valid as only tasks in preemptable
context can write to this buffer and only those that are running on the
CPU.

By using this method, where trace_marker open allocates the per CPU
buffers, trace_marker writes can access user space and even fault it in,
without having to allocate or take any locks of its own.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Cc: Luo Gengkun <luogengkun@huaweicloud.com>
Cc: Wattson CI <wattson-external@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: https://lore.kernel.org/20251008124510.6dba541a@gandalf.local.home
Fixes: 3d62ab32df ("tracing: Fix tracing_marker may trigger page fault during preempt_disable")
Reported-by: Runping Lai <runpinglai@google.com>
Tested-by: Runping Lai <runpinglai@google.com>
Closes: https://lore.kernel.org/linux-trace-kernel/20251007003417.3470979-2-runpinglai@google.com/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:17 +02:00
Steven Rostedt
afc0f246e0 tracing: Fix irqoff tracers on failure of acquiring calltime
commit c834a97962c708ff5bb8582ca76b0e1225feb675 upstream.

The functions irqsoff_graph_entry() and irqsoff_graph_return() both call
func_prolog_dec() that will test if the data->disable is already set and
if not, increment it and return. If it was set, it returns false and the
caller exits.

The caller of this function must decrement the disable counter, but misses
doing so if the calltime fails to be acquired.

Instead of exiting out when calltime is NULL, change the logic to do the
work if it is not NULL and still do the clean up at the end of the
function if it is NULL.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20251008114943.6f60f30f@gandalf.local.home
Fixes: a485ea9e3e ("tracing: Fix irqsoff and wakeup latency tracers when using function graph")
Reported-by: Sasha Levin <sashal@kernel.org>
Closes: https://lore.kernel.org/linux-trace-kernel/20251006175848.1906912-2-sashal@kernel.org/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:17 +02:00
Steven Rostedt
5d52012ce9 tracing: Fix wakeup tracers on failure of acquiring calltime
commit 4f7bf54b07e5acf79edd58dafede4096854776cd upstream.

The functions wakeup_graph_entry() and wakeup_graph_return() both call
func_prolog_preempt_disable() that will test if the data->disable is
already set and if not, increment it and disable preemption. If it was
set, it returns false and the caller exits.

The caller of this function must decrement the disable counter, but misses
doing so if the calltime fails to be acquired.

Instead of exiting out when calltime is NULL, change the logic to do the
work if it is not NULL and still do the clean up at the end of the
function if it is NULL.

Cc: stable@vger.kernel.org
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com>
Link: https://lore.kernel.org/20251008114835.027b878a@gandalf.local.home
Fixes: a485ea9e3e ("tracing: Fix irqsoff and wakeup latency tracers when using function graph")
Reported-by: Sasha Levin <sashal@kernel.org>
Closes: https://lore.kernel.org/linux-trace-kernel/20251006175848.1906912-1-sashal@kernel.org/
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:17 +02:00
Yuan Chen
5ebea65616 tracing: Fix race condition in kprobe initialization causing NULL pointer dereference
commit 9cf9aa7b0acfde7545c1a1d912576e9bab28dc6f upstream.

There is a critical race condition in kprobe initialization that can lead to
NULL pointer dereference and kernel crash.

[1135630.084782] Unable to handle kernel paging request at virtual address 0000710a04630000
...
[1135630.260314] pstate: 404003c9 (nZcv DAIF +PAN -UAO)
[1135630.269239] pc : kprobe_perf_func+0x30/0x260
[1135630.277643] lr : kprobe_dispatcher+0x44/0x60
[1135630.286041] sp : ffffaeff4977fa40
[1135630.293441] x29: ffffaeff4977fa40 x28: ffffaf015340e400
[1135630.302837] x27: 0000000000000000 x26: 0000000000000000
[1135630.312257] x25: ffffaf029ed108a8 x24: ffffaf015340e528
[1135630.321705] x23: ffffaeff4977fc50 x22: ffffaeff4977fc50
[1135630.331154] x21: 0000000000000000 x20: ffffaeff4977fc50
[1135630.340586] x19: ffffaf015340e400 x18: 0000000000000000
[1135630.349985] x17: 0000000000000000 x16: 0000000000000000
[1135630.359285] x15: 0000000000000000 x14: 0000000000000000
[1135630.368445] x13: 0000000000000000 x12: 0000000000000000
[1135630.377473] x11: 0000000000000000 x10: 0000000000000000
[1135630.386411] x9 : 0000000000000000 x8 : 0000000000000000
[1135630.395252] x7 : 0000000000000000 x6 : 0000000000000000
[1135630.403963] x5 : 0000000000000000 x4 : 0000000000000000
[1135630.412545] x3 : 0000710a04630000 x2 : 0000000000000006
[1135630.421021] x1 : ffffaeff4977fc50 x0 : 0000710a04630000
[1135630.429410] Call trace:
[1135630.434828]  kprobe_perf_func+0x30/0x260
[1135630.441661]  kprobe_dispatcher+0x44/0x60
[1135630.448396]  aggr_pre_handler+0x70/0xc8
[1135630.454959]  kprobe_breakpoint_handler+0x140/0x1e0
[1135630.462435]  brk_handler+0xbc/0xd8
[1135630.468437]  do_debug_exception+0x84/0x138
[1135630.475074]  el1_dbg+0x18/0x8c
[1135630.480582]  security_file_permission+0x0/0xd0
[1135630.487426]  vfs_write+0x70/0x1c0
[1135630.493059]  ksys_write+0x5c/0xc8
[1135630.498638]  __arm64_sys_write+0x24/0x30
[1135630.504821]  el0_svc_common+0x78/0x130
[1135630.510838]  el0_svc_handler+0x38/0x78
[1135630.516834]  el0_svc+0x8/0x1b0

kernel/trace/trace_kprobe.c: 1308
0xffff3df8995039ec <kprobe_perf_func+0x2c>:     ldr     x21, [x24,#120]
include/linux/compiler.h: 294
0xffff3df8995039f0 <kprobe_perf_func+0x30>:     ldr     x1, [x21,x0]

kernel/trace/trace_kprobe.c
1308: head = this_cpu_ptr(call->perf_events);
1309: if (hlist_empty(head))
1310: 	return 0;

crash> struct trace_event_call -o
struct trace_event_call {
  ...
  [120] struct hlist_head *perf_events;  //(call->perf_event)
  ...
}

crash> struct trace_event_call ffffaf015340e528
struct trace_event_call {
  ...
  perf_events = 0xffff0ad5fa89f088, //this value is correct, but x21 = 0
  ...
}

Race Condition Analysis:

The race occurs between kprobe activation and perf_events initialization:

  CPU0                                    CPU1
  ====                                    ====
  perf_kprobe_init
    perf_trace_event_init
      tp_event->perf_events = list;(1)
      tp_event->class->reg (2)← KPROBE ACTIVE
                                          Debug exception triggers
                                          ...
                                          kprobe_dispatcher
                                            kprobe_perf_func (tk->tp.flags & TP_FLAG_PROFILE)
                                              head = this_cpu_ptr(call->perf_events)(3)
                                              (perf_events is still NULL)

Problem:
1. CPU0 executes (1) assigning tp_event->perf_events = list
2. CPU0 executes (2) enabling kprobe functionality via class->reg()
3. CPU1 triggers and reaches kprobe_dispatcher
4. CPU1 checks TP_FLAG_PROFILE - condition passes (step 2 completed)
5. CPU1 calls kprobe_perf_func() and crashes at (3) because
   call->perf_events is still NULL

CPU1 sees that kprobe functionality is enabled but does not see that
perf_events has been assigned.

Add pairing read and write memory barriers to guarantee that if CPU1
sees that kprobe functionality is enabled, it must also see that
perf_events has been assigned.

Link: https://lore.kernel.org/all/20251001022025.44626-1-chenyuan_fl@163.com/

Fixes: 50d7805607 ("tracing/kprobes: Add probe handler dispatcher to support perf and ftrace concurrent use")
Cc: stable@vger.kernel.org
Signed-off-by: Yuan Chen <chenyuan@kylinos.cn>
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:17 +02:00
Sasha Levin
8da2138409 tracing: Fix lock imbalance in s_start() memory allocation failure path
commit 61e19cd2e5c5235326a13a68df1a2f8ec4eeed7b upstream.

When s_start() fails to allocate memory for set_event_iter, it returns NULL
before acquiring event_mutex. However, the corresponding s_stop() function
always tries to unlock the mutex, causing a lock imbalance warning:

  WARNING: bad unlock balance detected!
  6.17.0-rc7-00175-g2b2e0c04f78c #7 Not tainted
  -------------------------------------
  syz.0.85611/376514 is trying to release lock (event_mutex) at:
  [<ffffffff8dafc7a4>] traverse.part.0.constprop.0+0x2c4/0x650 fs/seq_file.c:131
  but there are no more locks to release!

The issue was introduced by commit b355247df1 ("tracing: Cache ':mod:'
events for modules not loaded yet") which added the kzalloc() allocation before
the mutex lock, creating a path where s_start() could return without locking
the mutex while s_stop() would still try to unlock it.

Fix this by unconditionally acquiring the mutex immediately after allocation,
regardless of whether the allocation succeeded.

Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/20250929113238.3722055-1-sashal@kernel.org
Fixes: b355247df1 ("tracing: Cache ":mod:" events for modules not loaded yet")
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2025-10-15 12:04:17 +02:00
Yazhou Tang
21167bf70d bpf: Reject negative offsets for ALU ops
[ Upstream commit 55c0ced59fe17dee34e9dfd5f7be63cbab207758 ]

When verifying BPF programs, the check_alu_op() function validates
instructions with ALU operations. The 'offset' field in these
instructions is a signed 16-bit integer.

The existing check 'insn->off > 1' was intended to ensure the offset is
either 0, or 1 for BPF_MOD/BPF_DIV. However, because 'insn->off' is
signed, this check incorrectly accepts all negative values (e.g., -1).

This commit tightens the validation by changing the condition to
'(insn->off != 0 && insn->off != 1)'. This ensures that any value
other than the explicitly permitted 0 and 1 is rejected, hardening the
verifier against malformed BPF programs.

Co-developed-by: Shenghao Yuan <shenghaoyuan0928@163.com>
Signed-off-by: Shenghao Yuan <shenghaoyuan0928@163.com>
Co-developed-by: Tianci Cao <ziye@zju.edu.cn>
Signed-off-by: Tianci Cao <ziye@zju.edu.cn>
Signed-off-by: Yazhou Tang <tangyazhou518@outlook.com>
Acked-by: Yonghong Song <yonghong.song@linux.dev>
Fixes: ec0e2da95f ("bpf: Support new signed div/mod instructions.")
Link: https://lore.kernel.org/r/tencent_70D024BAE70A0A309A4781694C7B764B0608@qq.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:04:14 +02:00
Brahmajit Das
b9ef496322 bpf: Skip scalar adjustment for BPF_NEG if dst is a pointer
[ Upstream commit 34904582b502a86fdb4d7984b12cacd2faabbe0d ]

In check_alu_op(), the verifier currently calls check_reg_arg() and
adjust_scalar_min_max_vals() unconditionally for BPF_NEG operations.
However, if the destination register holds a pointer, these scalar
adjustments are unnecessary and potentially incorrect.

This patch adds a check to skip the adjustment logic when the destination
register contains a pointer.

Reported-by: syzbot+d36d5ae81e1b0a53ef58@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=d36d5ae81e1b0a53ef58
Fixes: aced132599 ("bpf: Add range tracking for BPF_NEG")
Suggested-by: KaFai Wan <kafai.wan@linux.dev>
Suggested-by: Eduard Zingerman <eddyz87@gmail.com>
Signed-off-by: Brahmajit Das <listout@listout.xyz>
Acked-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20251001191739.2323644-2-listout@listout.xyz
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:04:14 +02:00
Zqiang
d9ae3a91c4 srcu/tiny: Remove preempt_disable/enable() in srcu_gp_start_if_needed()
[ Upstream commit e6a43aeb71852a39432332dcc3a6d11bb464b075 ]

Currently, the srcu_gp_start_if_needed() is always be invoked in
preempt disable's critical section, this commit therefore remove
redundant preempt_disable/enable() in srcu_gp_start_if_needed()
and adds a call to lockdep_assert_preemption_disabled() in order
to enable lockdep to diagnose mistaken invocations of this function
from preempts-enabled code.

Fixes: 65b4a59557 ("srcu: Make Tiny SRCU explicitly disable preemption")
Signed-off-by: Zqiang <qiang.zhang@linux.dev>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:03:58 +02:00
Daniel Borkmann
c1ad19b5d8 bpf: Enforce expected_attach_type for tailcall compatibility
[ Upstream commit 4540aed51b12bc13364149bf95f6ecef013197c0 ]

Yinhao et al. recently reported:

  Our fuzzer tool discovered an uninitialized pointer issue in the
  bpf_prog_test_run_xdp() function within the Linux kernel's BPF subsystem.
  This leads to a NULL pointer dereference when a BPF program attempts to
  deference the txq member of struct xdp_buff object.

The test initializes two programs of BPF_PROG_TYPE_XDP: progA acts as the
entry point for bpf_prog_test_run_xdp() and its expected_attach_type can
neither be of be BPF_XDP_DEVMAP nor BPF_XDP_CPUMAP. progA calls into a slot
of a tailcall map it owns. progB's expected_attach_type must be BPF_XDP_DEVMAP
to pass xdp_is_valid_access() validation. The program returns struct xdp_md's
egress_ifindex, and the latter is only allowed to be accessed under mentioned
expected_attach_type. progB is then inserted into the tailcall which progA
calls.

The underlying issue goes beyond XDP though. Another example are programs
of type BPF_PROG_TYPE_CGROUP_SOCK_ADDR. sock_addr_is_valid_access() as well
as sock_addr_func_proto() have different logic depending on the programs'
expected_attach_type. Similarly, a program attached to BPF_CGROUP_INET4_GETPEERNAME
should not be allowed doing a tailcall into a program which calls bpf_bind()
out of BPF which is only enabled for BPF_CGROUP_INET4_CONNECT.

In short, specifying expected_attach_type allows to open up additional
functionality or restrictions beyond what the basic bpf_prog_type enables.
The use of tailcalls must not violate these constraints. Fix it by enforcing
expected_attach_type in __bpf_prog_map_compatible().

Note that we only enforce this for tailcall maps, but not for BPF devmaps or
cpumaps: There, the programs are invoked through dev_map_bpf_prog_run*() and
cpu_map_bpf_prog_run*() which set up a new environment / context and therefore
these situations are not prone to this issue.

Fixes: 5e43f899b0 ("bpf: Check attach type at prog load time")
Reported-by: Yinhao Hu <dddddd@hust.edu.cn>
Reported-by: Kaiyan Mei <M202472210@hust.edu.cn>
Reviewed-by: Dongliang Mu <dzm91@hust.edu.cn>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/r/20250926171201.188490-1-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:03:39 +02:00
Rafael J. Wysocki
359097d709 smp: Fix up and expand the smp_call_function_many() kerneldoc
[ Upstream commit ccf09357ffef2ab472369ab9cdf470c9bc9b821a ]

The smp_call_function_many() kerneldoc comment got out of sync with the
function definition (bool parameter "wait" is incorrectly described as a
bitmask in it), so fix it up by copying the "wait" description from the
smp_call_function() kerneldoc and add information regarding the handling
of the local CPU to it.

Fixes: 49b3bd213a ("smp: Fix all kernel-doc warnings")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:03:36 +02:00
Eduard Zingerman
3861e7c432 bpf: dont report verifier bug for missing bpf_scc_visit on speculative path
[ Upstream commit a3c73d629ea1373af3c0c954d41fd1af555492e3 ]

Syzbot generated a program that triggers a verifier_bug() call in
maybe_exit_scc(). maybe_exit_scc() assumes that, when called for a
state with insn_idx in some SCC, there should be an instance of struct
bpf_scc_visit allocated for that SCC. Turns out the assumption does
not hold for speculative execution paths. See example in the next
patch.

maybe_scc_exit() is called from update_branch_counts() for states that
reach branch count of zero, meaning that path exploration for a
particular path is finished. Path exploration can finish in one of
three ways:
a. Verification error is found. In this case, update_branch_counts()
   is called only for non-speculative paths.
b. Top level BPF_EXIT is reached. Such instructions are never a part of
   an SCC, so compute_scc_callchain() in maybe_scc_exit() will return
   false, and maybe_scc_exit() will return early.
c. A checkpoint is reached and matched. Checkpoints are created by
   is_state_visited(), which calls maybe_enter_scc(), which allocates
   bpf_scc_visit instances for checkpoints within SCCs.

Hence, for non-speculative symbolic execution paths, the assumption
still holds: if maybe_scc_exit() is called for a state within an SCC,
bpf_scc_visit instance must exist.

This patch removes the verifier_bug() call for speculative paths.

Fixes: c9e31900b5 ("bpf: propagate read/precision marks over state graph backedges")
Reported-by: syzbot+3afc814e8df1af64b653@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/bpf/68c85acd.050a0220.2ff435.03a4.GAE@google.com/
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250916212251.3490455-1-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:03:35 +02:00
Bibo Mao
f1c3bb6b40 tick: Do not set device to detached state in tick_shutdown()
[ Upstream commit fe2a449a45b13df1562419e0104b4777b6ea5248 ]

tick_shutdown() sets the state of the clockevent device to detached
first and the invokes clockevents_exchange_device(), which in turn
invokes clockevents_switch_state().

But clockevents_switch_state() returns without invoking the device shutdown
callback as the device is already in detached state. As a consequence the
timer device is not shutdown when a CPU goes offline.

tick_shutdown() does this because it was originally invoked on a online CPU
and not on the outgoing CPU. It therefore could not access the clockevent
device of the already offlined CPU and just set the state.

Since commit 3b1596a21f tick_shutdown() is called on the outgoing CPU, so
the hardware device can be accessed.

Remove the state set before calling clockevents_exchange_device(), so that
the subsequent clockevents_switch_state() handles the state transition and
invokes the shutdown callback of the clockevent device.

[ tglx: Massaged change log ]

Fixes: 3b1596a21f ("clockevents: Shutdown and unregister current clockevents at CPUHP_AP_TICK_DYING")
Signed-off-by: Bibo Mao <maobibo@loongson.cn>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/all/20250906064952.3749122-2-maobibo@loongson.cn
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:03:26 +02:00
Brian Norris
6df16e7ceb genirq/test: Ensure CPU 1 is online for hotplug test
[ Upstream commit 8ad25ebfa70e86860559b306bbc923c7db4fcac6 ]

It's possible to run these tests on platforms that think they have a
hotpluggable CPU1, but for whatever reason, CPU1 is not online and can't be
brought online:

    # irq_cpuhotplug_test: EXPECTATION FAILED at kernel/irq/irq_test.c:210
    Expected remove_cpu(1) == 0, but
        remove_cpu(1) == 1 (0x1)
CPU1: failed to boot: -38
    # irq_cpuhotplug_test: EXPECTATION FAILED at kernel/irq/irq_test.c:214
    Expected add_cpu(1) == 0, but
        add_cpu(1) == -38 (0xffffffffffffffda)

Check that CPU1 is actually online before trying to run the test.

Fixes: 66067c3c8a ("genirq: Add kunit tests for depth counts")
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Brian Norris <briannorris@chromium.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Tested-by: Guenter Roeck <linux@roeck-us.net>
Reviewed-by: David Gow <davidgow@google.com>
Link: https://lore.kernel.org/all/20250822190140.2154646-7-briannorris@chromium.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
2025-10-15 12:03:24 +02:00