[moderation] [perf?] KCSAN: data-race in __perf_event_read_value / perf_event_set_state (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4a95bc121ccd Merge tag 'rproc-v6.15-fixes' of git://git.ke..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=1592e0e8580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ea93cce608593e25
dashboard link: https://syzkaller.appspot.com/bug?extid=78cf826e0f81c828caf7
compiler: Debian clang version 20.1.6 (++20250514063057+1e4d39e07757-1~exp1~20250514183223.118), Debian LLD 20.1.6
CC: [ac...@kernel.org adrian...@intel.com alexander...@linux.intel.com iro...@google.com jo...@kernel.org kan....@linux.intel.com linux-...@vger.kernel.org linux-pe...@vger.kernel.org mark.r...@arm.com mi...@redhat.com namh...@kernel.org pet...@infradead.org]

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/c157aef2e681/disk-4a95bc12.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/285f64f278b5/vmlinux-4a95bc12.xz
kernel image: https://storage.googleapis.com/syzbot-assets/cef6e2a0d5ae/bzImage-4a95bc12.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+78cf82...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in __perf_event_read_value / perf_event_set_state

write to 0xffff888119aa1628 of 8 bytes by task 10255 on cpu 0:
__perf_update_times kernel/events/core.c:-1 [inline]
perf_event_update_time kernel/events/core.c:721 [inline]
perf_event_set_state+0x195/0x440 kernel/events/core.c:740
event_sched_in+0xee/0x6f0 kernel/events/core.c:2652
group_sched_in kernel/events/core.c:2701 [inline]
merge_sched_in+0x258/0xa60 kernel/events/core.c:3935
visit_groups_merge+0x9db/0xfd0 kernel/events/core.c:3880
pmu_groups_sched_in kernel/events/core.c:3966 [inline]
__pmu_ctx_sched_in+0x8a/0xb0 kernel/events/core.c:-1
ctx_sched_in+0x325/0x370 kernel/events/core.c:4029
perf_event_sched_in kernel/events/core.c:-1 [inline]
perf_event_context_sched_in kernel/events/core.c:4076 [inline]
__perf_event_task_sched_in+0x660/0xaa0 kernel/events/core.c:4105
perf_event_task_sched_in include/linux/perf_event.h:1572 [inline]
finish_task_switch+0x21a/0x2b0 kernel/sched/core.c:5245
context_switch kernel/sched/core.c:5385 [inline]
__schedule+0x6a2/0xb20 kernel/sched/core.c:6767
__schedule_loop kernel/sched/core.c:6845 [inline]
schedule+0x5f/0xd0 kernel/sched/core.c:6860
futex_wait_queue+0xa8/0x110 kernel/futex/waitwake.c:369
__futex_wait+0xb4/0x1b0 kernel/futex/waitwake.c:668
futex_wait+0x9d/0x1d0 kernel/futex/waitwake.c:696
do_futex+0x2bf/0x380 kernel/futex/syscalls.c:102
__do_sys_futex kernel/futex/syscalls.c:179 [inline]
__se_sys_futex+0x2ed/0x360 kernel/futex/syscalls.c:160
__x64_sys_futex+0x78/0x90 kernel/futex/syscalls.c:160
x64_sys_call+0x1331/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:203
do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
do_syscall_64+0xd0/0x1a0 arch/x86/entry/syscall_64.c:94
entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888119aa1628 of 8 bytes by task 10265 on cpu 1:
__perf_event_read_value+0x82/0x1d0 kernel/events/core.c:5832
perf_read_one kernel/events/core.c:5989 [inline]
__perf_read kernel/events/core.c:6042 [inline]
perf_read+0x173/0x4d0 kernel/events/core.c:6059
loop_rw_iter+0x2c6/0x3f0 io_uring/rw.c:-1
io_iter_do_read io_uring/rw.c:826 [inline]
__io_read+0xbc2/0xc10 io_uring/rw.c:937
io_read+0x1c/0x60 io_uring/rw.c:1016
__io_issue_sqe+0xfe/0x2e0 io_uring/io_uring.c:1734
io_issue_sqe+0x53/0x970 io_uring/io_uring.c:1757
io_wq_submit_work+0x3f7/0x5f0 io_uring/io_uring.c:1869
io_worker_handle_work+0x46a/0x9f0 io_uring/io-wq.c:615
io_wq_worker+0x22e/0x870 io_uring/io-wq.c:669
ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:153
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000069e4b57 -> 0x00000000069ed343

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 10265 Comm: iou-wrk-10255 Not tainted 6.15.0-rc7-syzkaller-00007-g4a95bc121ccd #0 PREEMPT(voluntary)
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.