syzbot


KCSAN: data-race in __perf_event_read_value / perf_event_set_state (2)

Status: moderation: reported on 2024/10/19 12:41
Subsystems: perf
[Documentation on labels]
Reported-by: syzbot+bbc432eb1c7b22f9e855@syzkaller.appspotmail.com
First crash: 3d08h, last: 3d08h
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __perf_event_read_value / perf_event_set_state perf 1 143d 143d 0/28 auto-obsoleted due to no activity on 2024/07/06 04:07

Sample crash report:
==================================================================
BUG: KCSAN: data-race in __perf_event_read_value / perf_event_set_state

write to 0xffff88810485f4e8 of 8 bytes by task 8299 on cpu 0:
 perf_event_update_time kernel/events/core.c:675 [inline]
 perf_event_set_state+0x1a1/0x3f0 kernel/events/core.c:694
 event_sched_out+0x2c8/0x4a0 kernel/events/core.c:2335
 group_sched_out kernel/events/core.c:2359 [inline]
 __pmu_ctx_sched_out+0x3aa/0x4e0 kernel/events/core.c:3339
 ctx_sched_out+0x267/0x2c0 kernel/events/core.c:3420
 task_ctx_sched_out kernel/events/core.c:2739 [inline]
 perf_event_context_sched_out kernel/events/core.c:3664 [inline]
 __perf_event_task_sched_out+0x411/0xfe0 kernel/events/core.c:3763
 perf_event_task_sched_out include/linux/perf_event.h:1519 [inline]
 prepare_task_switch kernel/sched/core.c:5126 [inline]
 context_switch kernel/sched/core.c:5269 [inline]
 __schedule+0x931/0x940 kernel/sched/core.c:6682
 __schedule_loop kernel/sched/core.c:6759 [inline]
 schedule+0x55/0xc0 kernel/sched/core.c:6774
 futex_wait_queue kernel/futex/waitwake.c:370 [inline]
 __futex_wait+0x141/0x290 kernel/futex/waitwake.c:669
 futex_wait+0x99/0x1c0 kernel/futex/waitwake.c:697
 do_futex+0x276/0x370 kernel/futex/syscalls.c:102
 __do_sys_futex kernel/futex/syscalls.c:179 [inline]
 __se_sys_futex+0x25d/0x3a0 kernel/futex/syscalls.c:160
 __x64_sys_futex+0x78/0x90 kernel/futex/syscalls.c:160
 x64_sys_call+0x23c4/0x2d60 arch/x86/include/generated/asm/syscalls_64.h:203
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff88810485f4e8 of 8 bytes by task 8322 on cpu 1:
 __perf_event_read_value+0xba/0x1c0 kernel/events/core.c:5608
 perf_read_one kernel/events/core.c:5763 [inline]
 __perf_read kernel/events/core.c:5816 [inline]
 perf_read+0x174/0x4a0 kernel/events/core.c:5833
 loop_rw_iter+0x237/0x360
 io_iter_do_read io_uring/rw.c:773 [inline]
 __io_read+0xa5a/0xaf0 io_uring/rw.c:865
 io_read+0x1e/0x60 io_uring/rw.c:943
 io_issue_sqe+0x150/0xcc0 io_uring/io_uring.c:1739
 io_wq_submit_work+0x474/0x5f0 io_uring/io_uring.c:1848
 io_worker_handle_work+0x486/0x9d0 io_uring/io-wq.c:601
 io_wq_worker+0x286/0x820 io_uring/io-wq.c:655
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x00000000059b617a -> 0x00000000059b9f48

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 8322 Comm: iou-wrk-8299 Tainted: G        W          6.12.0-rc3-syzkaller-00389-g3d5ad2d4eca3 #0
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/10/19 12:40 upstream 3d5ad2d4eca3 cd6fc0a3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / perf_event_set_state
* Struck through repros no longer work on HEAD.