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KCSAN: data-race in __perf_event_read_value / event_sched_out (6)

Status: auto-obsoleted due to no activity on 2023/01/16 16:53
Subsystems: perf
[Documentation on labels]
First crash: 509d, last: 509d
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 perf 6 867d 942d 0/26 auto-closed as invalid on 2022/01/12 21:04
upstream KCSAN: data-race in __perf_event_read_value / event_sched_out (5) perf 5 547d 604d 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 670d 670d 0/26 auto-closed as invalid on 2022/07/28 22:06

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

write to 0xffff88814f818658 of 8 bytes by task 11737 on cpu 0:
 perf_event_update_time kernel/events/core.c:647 [inline]
 perf_event_set_state kernel/events/core.c:666 [inline]
 event_sched_out+0x5ab/0xb00 kernel/events/core.c:2300
 group_sched_out+0xdb/0x1d0 kernel/events/core.c:2326
 ctx_sched_out+0x2b9/0x310 kernel/events/core.c:3288
 task_ctx_sched_out kernel/events/core.c:2663 [inline]
 perf_event_context_sched_out kernel/events/core.c:3506 [inline]
 __perf_event_task_sched_out+0x64a/0xfa0 kernel/events/core.c:3609
 prepare_task_switch kernel/sched/core.c:5018 [inline]
 context_switch kernel/sched/core.c:5160 [inline]
 __schedule+0x440/0x6e0 kernel/sched/core.c:6521
 schedule+0x51/0x80 kernel/sched/core.c:6597
 futex_wait_queue kernel/futex/waitwake.c:355 [inline]
 futex_wait+0x1a5/0x420 kernel/futex/waitwake.c:656
 do_futex+0x283/0x2b0 kernel/futex/syscalls.c:106
 __do_sys_futex kernel/futex/syscalls.c:183 [inline]
 __se_sys_futex+0xe8/0x350 kernel/futex/syscalls.c:164
 __x64_sys_futex+0x74/0x80 kernel/futex/syscalls.c:164
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

read to 0xffff88814f818658 of 8 bytes by task 11757 on cpu 1:
 __perf_event_read_value+0x84/0x1d0 kernel/events/core.c:5237
 perf_read_one kernel/events/core.c:5370 [inline]
 __perf_read kernel/events/core.c:5423 [inline]
 perf_read+0x2b8/0x610 kernel/events/core.c:5440
 vfs_read+0x198/0x560 fs/read_write.c:468
 ksys_read+0xe8/0x1a0 fs/read_write.c:613
 __do_sys_read fs/read_write.c:623 [inline]
 __se_sys_read fs/read_write.c:621 [inline]
 __x64_sys_read+0x3e/0x50 fs/read_write.c:621
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

value changed: 0x0000000000ad36e4 -> 0x0000000000ad7d3d

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 11757 Comm: syz-executor.2 Not tainted 6.1.0-rc7-syzkaller-00103-gef4d3ea40565-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2022/12/01 23:22 upstream ef4d3ea40565 e080de16 .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.