syzbot


KCSAN: data-race in add_timer_on / timer_clear_idle (2)

Status: closed as invalid on 2020/06/18 14:24
Subsystems: kernel
[Documentation on labels]
First crash: 1644d, last: 1410d
Similar bugs (2)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in add_timer_on / timer_clear_idle kernel 1 1656d 1656d 0/26 closed as invalid on 2019/10/18 14:11
upstream KCSAN: data-race in add_timer_on / timer_clear_idle (3) kernel 30 1358d 1405d 0/26 auto-closed as invalid on 2020/09/09 13:18

Sample crash report:
==================================================================
BUG: KCSAN: data-race in add_timer_on / timer_clear_idle

write to 0xffff88812c11dca4 of 1 bytes by task 0 on cpu 1:
 timer_clear_idle+0x3d/0x50 kernel/time/timer.c:1676
 tick_nohz_restart_sched_tick kernel/time/tick-sched.c:860 [inline]
 __tick_nohz_idle_restart_tick+0x32/0x1a0 kernel/time/tick-sched.c:1161
 tick_nohz_idle_exit+0x19c/0x1d0 kernel/time/tick-sched.c:1202
 do_idle+0xac/0x290 kernel/sched/idle.c:282
 cpu_startup_entry+0x14/0x20 kernel/sched/idle.c:361
 start_secondary+0x169/0x1b0 arch/x86/kernel/smpboot.c:268
 secondary_startup_64+0xa4/0xb0 arch/x86/kernel/head_64.S:242

read to 0xffff88812c11dca4 of 1 bytes by interrupt on cpu 0:
 forward_timer_base kernel/time/timer.c:892 [inline]
 add_timer_on+0x21f/0x2c0 kernel/time/timer.c:1172
 clocksource_watchdog+0x699/0x7c0 kernel/time/clocksource.c:303
 call_timer_fn+0x58/0x2e0 kernel/time/timer.c:1405
 expire_timers kernel/time/timer.c:1450 [inline]
 __run_timers kernel/time/timer.c:1774 [inline]
 __run_timers kernel/time/timer.c:1741 [inline]
 run_timer_softirq+0xb14/0xbd0 kernel/time/timer.c:1787
 __do_softirq+0x118/0x34a kernel/softirq.c:292
 run_ksoftirqd+0x41/0x60 kernel/softirq.c:604
 smpboot_thread_fn+0x374/0x4a0 kernel/smpboot.c:165
 kthread+0x203/0x230 kernel/kthread.c:268
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:352

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 9 Comm: ksoftirqd/0 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (30):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/14 06:31 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a61674a5 .config console log report ci2-upstream-kcsan-gce
2020/06/12 15:09 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 819b58b0 .config console log report ci2-upstream-kcsan-gce
2020/05/21 11:04 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 4afdfa20 .config console log report ci2-upstream-kcsan-gce
2020/04/25 16:32 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a113ba38 .config console log report ci2-upstream-kcsan-gce
2020/04/03 21:38 https://github.com/google/ktsan.git kcsan 40959e34d670 ef26b610 .config console log report ci2-upstream-kcsan-gce
2020/03/30 11:44 https://github.com/google/ktsan.git kcsan 40959e34d670 c8d1cc20 .config console log report ci2-upstream-kcsan-gce
2020/02/26 00:40 https://github.com/google/ktsan.git kcsan 766d004d1b85 4c886d6a .config console log report ci2-upstream-kcsan-gce
2020/02/24 10:43 https://github.com/google/ktsan.git kcsan 766d004d1b85 1253d6f0 .config console log report ci2-upstream-kcsan-gce
2020/02/07 20:01 https://github.com/google/ktsan.git kcsan 6cccb8ba35bd 06150bf1 .config console log report ci2-upstream-kcsan-gce
2020/01/31 04:57 https://github.com/google/ktsan.git kcsan 245a43005292 5ed23f9a .config console log report ci2-upstream-kcsan-gce
2020/01/20 10:22 https://github.com/google/ktsan.git kcsan 245a43005292 c40da18c .config console log report ci2-upstream-kcsan-gce
2020/01/19 00:27 https://github.com/google/ktsan.git kcsan 245a43005292 bc8bc756 .config console log report ci2-upstream-kcsan-gce
2020/01/12 15:16 https://github.com/google/ktsan.git kcsan 245a43005292 31290a45 .config console log report ci2-upstream-kcsan-gce
2019/12/30 17:06 https://github.com/google/ktsan.git kcsan 245a43005292 6b36d338 .config console log report ci2-upstream-kcsan-gce
2019/12/19 14:38 https://github.com/google/ktsan.git kcsan 245a43005292 36650b4b .config console log report ci2-upstream-kcsan-gce
2019/12/17 01:56 https://github.com/google/ktsan.git kcsan 245a43005292 d13d7958 .config console log report ci2-upstream-kcsan-gce
2019/12/16 11:45 https://github.com/google/ktsan.git kcsan 245a43005292 0ae38e44 .config console log report ci2-upstream-kcsan-gce
2019/12/11 16:04 https://github.com/google/ktsan.git kcsan ef798c30ba4e 0d368675 .config console log report ci2-upstream-kcsan-gce
2019/12/10 23:06 https://github.com/google/ktsan.git kcsan ef798c30ba4e 101194eb .config console log report ci2-upstream-kcsan-gce
2019/12/10 23:02 https://github.com/google/ktsan.git kcsan ef798c30ba4e 101194eb .config console log report ci2-upstream-kcsan-gce
2019/12/06 03:55 https://github.com/google/ktsan.git kcsan ef798c30ba4e 98b4ef2d .config console log report ci2-upstream-kcsan-gce
2019/11/19 12:45 https://github.com/google/ktsan.git kcsan 5863cc791e4c 432c7650 .config console log report ci2-upstream-kcsan-gce
2019/11/18 14:58 https://github.com/google/ktsan.git kcsan 5863cc791e4c d5696d51 .config console log report ci2-upstream-kcsan-gce
2019/11/08 10:22 https://github.com/google/ktsan.git kcsan 94c006602e13 1e35461e .config console log report ci2-upstream-kcsan-gce
2019/11/02 21:17 https://github.com/google/ktsan.git kcsan 05f2236801fe d603afc9 .config console log report ci2-upstream-kcsan-gce
2019/11/01 19:08 https://github.com/google/ktsan.git kcsan 05f2236801fe 997ccc67 .config console log report ci2-upstream-kcsan-gce
2019/10/31 22:40 https://github.com/google/ktsan.git kcsan 05f2236801fe a41ca8fa .config console log report ci2-upstream-kcsan-gce
2019/10/28 17:45 https://github.com/google/ktsan.git kcsan 05f2236801fe 439d7b14 .config console log report ci2-upstream-kcsan-gce
2019/10/26 00:38 https://github.com/google/ktsan.git kcsan 05f2236801fe 413926c5 .config console log report ci2-upstream-kcsan-gce
2019/10/24 08:07 https://github.com/google/ktsan.git kcsan 05f2236801fe d01bb02a .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.