syzbot


KCSAN: data-race in __perf_event_read_value / event_sched_out

Status: auto-closed as invalid on 2022/01/12 21:04
Subsystems: perf
[Documentation on labels]
First crash: 943d, last: 868d
Similar bugs (5)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in __perf_event_read_value / event_sched_out (5) perf 5 548d 605d 0/26 auto-obsoleted due to no activity on 2022/11/29 10:56
upstream KCSAN: data-race in __perf_event_read_value / event_sched_out (2) perf 3 791d 830d 0/26 auto-closed as invalid on 2022/03/30 13:56
upstream KCSAN: data-race in __perf_event_read_value / event_sched_out (3) perf 2 733d 750d 0/26 auto-closed as invalid on 2022/05/27 15:32
upstream KCSAN: data-race in __perf_event_read_value / event_sched_out (4) perf 1 671d 671d 0/26 auto-closed as invalid on 2022/07/28 22:06
upstream KCSAN: data-race in __perf_event_read_value / event_sched_out (6) perf 1 510d 510d 0/26 auto-obsoleted due to no activity on 2023/01/16 16:53

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

write to 0xffff8881345fecc0 of 8 bytes by task 21381 on cpu 1:
 perf_event_update_time kernel/events/core.c:647 [inline]
 perf_event_set_state kernel/events/core.c:666 [inline]
 event_sched_out+0x309/0x830 kernel/events/core.c:2293
 group_sched_out+0xf0/0x1f0 kernel/events/core.c:2319
 ctx_sched_out+0x391/0x450 kernel/events/core.c:3289
 task_ctx_sched_out kernel/events/core.c:2687 [inline]
 perf_event_context_sched_out kernel/events/core.c:3494 [inline]
 __perf_event_task_sched_out+0x679/0xf00 kernel/events/core.c:3597
 perf_event_task_sched_out include/linux/perf_event.h:1232 [inline]
 prepare_task_switch+0x13b/0x140 kernel/sched/core.c:4782
 context_switch kernel/sched/core.c:4924 [inline]
 __schedule+0x397/0x6a0 kernel/sched/core.c:6253
 preempt_schedule_common kernel/sched/core.c:6419 [inline]
 __cond_resched+0x3f/0x90 kernel/sched/core.c:8132
 _cond_resched include/linux/sched.h:2017 [inline]
 tctx_task_work+0x6a/0x410 fs/io_uring.c:2249
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_signal include/linux/tracehook.h:214 [inline]
 handle_signal_work kernel/entry/common.c:146 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:172 [inline]
 exit_to_user_mode_prepare+0x102/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff8881345fecc0 of 8 bytes by task 21396 on cpu 0:
 __perf_event_read_value+0x84/0x1f0 kernel/events/core.c:5218
 perf_read_one kernel/events/core.c:5347 [inline]
 __perf_read kernel/events/core.c:5398 [inline]
 perf_read+0x2b8/0x5c0 kernel/events/core.c:5415
 loop_rw_iter+0x257/0x350
 io_iter_do_read fs/io_uring.c:3503 [inline]
 io_read fs/io_uring.c:3558 [inline]
 io_issue_sqe+0x521e/0x55e0 fs/io_uring.c:6671
 io_wq_submit_work+0x1c5/0x370 fs/io_uring.c:6836
 io_worker_handle_work+0x4ca/0xbd0 fs/io-wq.c:563
 io_wqe_worker+0x1bc/0x4f0 fs/io-wq.c:619
 ret_from_fork+0x1f/0x30

value changed: 0x00000000020c613a -> 0x00000000020c9302

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 21396 Comm: iou-wrk-21381 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (6):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2021/12/08 20:56 upstream 2a987e65025e a4a2a501 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / event_sched_out
2021/11/17 17:36 upstream ee1703cda8dc cafff8b6 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / event_sched_out
2021/11/17 13:18 upstream 8ab774587903 cafff8b6 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / event_sched_out
2021/10/27 17:36 upstream d25f27432f80 be531bb4 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / event_sched_out
2021/09/29 22:46 upstream a4e6f95a891a e08fe937 .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / event_sched_out
2021/09/24 20:28 upstream f9e36107ec70 8cac236e .config console log report info ci2-upstream-kcsan-gce KCSAN: data-race in __perf_event_read_value / event_sched_out
* Struck through repros no longer work on HEAD.