syzbot


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

Status: auto-closed as invalid on 2020/07/23 04:33
Subsystems: kernel
[Documentation on labels]
Reported-by: syzbot+c051abeff5e2e8ac40f0@syzkaller.appspotmail.com
First crash: 1859d, last: 1620d
Discussions (1)
Title Replies (including bot) Last reply
KCSAN: data-race in add_timer / timer_clear_idle (2) 0 (1) 2019/12/12 23:33
Similar bugs (1)
Kernel Title Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream KCSAN: data-race in add_timer / timer_clear_idle batman 2 1867d 1873d 0/28 closed as invalid on 2019/10/18 14:11

Sample crash report:
==================================================================
BUG: KCSAN: data-race in add_timer / 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 task 46 on cpu 0:
 forward_timer_base kernel/time/timer.c:892 [inline]
 __mod_timer kernel/time/timer.c:1010 [inline]
 add_timer+0x2e6/0x550 kernel/time/timer.c:1137
 __queue_delayed_work+0x13c/0x1d0 kernel/workqueue.c:1648
 queue_delayed_work_on+0xef/0x110 kernel/workqueue.c:1673
 queue_delayed_work include/linux/workqueue.h:522 [inline]
 batadv_nc_start_timer net/batman-adv/network-coding.c:79 [inline]
 batadv_nc_worker+0x24f/0x340 net/batman-adv/network-coding.c:740
 process_one_work+0x424/0x930 kernel/workqueue.c:2268
 worker_thread+0x9a/0x7e0 kernel/workqueue.c:2414
 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: 46 Comm: kworker/u4:3 Not tainted 5.7.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_nc_worker
==================================================================

Crashes (218):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/06/18 04:33 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 d45a4d69 .config console log report ci2-upstream-kcsan-gce
2020/06/17 16:03 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b6c46f43 .config console log report ci2-upstream-kcsan-gce
2020/06/16 23:09 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b9f3810b .config console log report ci2-upstream-kcsan-gce
2020/06/16 15:41 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 4ea9d964 .config console log report ci2-upstream-kcsan-gce
2020/06/15 20:17 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 baca2611 .config console log report ci2-upstream-kcsan-gce
2020/06/15 09:40 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 8e3ab941 .config console log report ci2-upstream-kcsan-gce
2020/06/14 17:28 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2a22c77a .config console log report ci2-upstream-kcsan-gce
2020/06/12 19:20 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 3036d6fd .config console log report ci2-upstream-kcsan-gce
2020/06/11 21:04 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 1beaee21 .config console log report ci2-upstream-kcsan-gce
2020/06/11 02:55 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 3ab7a05a .config console log report ci2-upstream-kcsan-gce
2020/06/10 21:54 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 5caaad3a .config console log report ci2-upstream-kcsan-gce
2020/06/10 02:06 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 860c4de9 .config console log report ci2-upstream-kcsan-gce
2020/06/09 12:28 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 092934c1 .config console log report ci2-upstream-kcsan-gce
2020/06/09 04:45 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 0d60b78a .config console log report ci2-upstream-kcsan-gce
2020/06/08 02:48 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 7751efd0 .config console log report ci2-upstream-kcsan-gce
2020/06/06 16:39 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e6b89e4e .config console log report ci2-upstream-kcsan-gce
2020/06/06 01:57 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 c3e9afb3 .config console log report ci2-upstream-kcsan-gce
2020/06/05 13:47 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 d36418e9 .config console log report ci2-upstream-kcsan-gce
2020/06/05 08:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 2420d1bc .config console log report ci2-upstream-kcsan-gce
2020/06/04 01:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 b0d1c0d5 .config console log report ci2-upstream-kcsan-gce
2020/06/03 14:24 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a5ce5de0 .config console log report ci2-upstream-kcsan-gce
2020/06/03 04:11 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f3ba1b5b .config console log report ci2-upstream-kcsan-gce
2020/06/02 18:20 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 52fd7b7d .config console log report ci2-upstream-kcsan-gce
2020/05/30 19:41 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6f3e1c7c .config console log report ci2-upstream-kcsan-gce
2020/05/30 06:14 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 954bd312 .config console log report ci2-upstream-kcsan-gce
2020/05/28 17:19 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 c7192a2f .config console log report ci2-upstream-kcsan-gce
2020/05/26 03:08 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 8ca3b7d2 .config console log report ci2-upstream-kcsan-gce
2020/05/25 13:41 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 73964a9b .config console log report ci2-upstream-kcsan-gce
2020/05/25 03:57 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 11284182 .config console log report ci2-upstream-kcsan-gce
2020/05/24 16:08 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 ce7ca010 .config console log report ci2-upstream-kcsan-gce
2020/05/20 12:20 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 1255f02a .config console log report ci2-upstream-kcsan-gce
2020/05/19 00:07 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 684d3606 .config console log report ci2-upstream-kcsan-gce
2020/05/18 11:37 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 24d91142 .config console log report ci2-upstream-kcsan-gce
2020/05/15 17:17 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 d7f9fffa .config console log report ci2-upstream-kcsan-gce
2020/05/14 00:03 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a885920d .config console log report ci2-upstream-kcsan-gce
2020/05/12 19:02 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a44eb8f7 .config console log report ci2-upstream-kcsan-gce
2020/05/12 08:42 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 a497a5b4 .config console log report ci2-upstream-kcsan-gce
2020/05/11 07:13 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 f8f57555 .config console log report ci2-upstream-kcsan-gce
2020/05/10 05:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 8742a2b9 .config console log report ci2-upstream-kcsan-gce
2020/05/09 15:23 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 88cb3e92 .config console log report ci2-upstream-kcsan-gce
2020/05/09 01:07 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 e97b06d3 .config console log report ci2-upstream-kcsan-gce
2020/05/08 10:30 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 fe4122c3 .config console log report ci2-upstream-kcsan-gce
2020/05/08 05:31 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 6c70a1c2 .config console log report ci2-upstream-kcsan-gce
2020/05/07 10:26 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 98cbd87b .config console log report ci2-upstream-kcsan-gce
2020/05/06 17:25 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 4618eb2d .config console log report ci2-upstream-kcsan-gce
2020/05/06 01:00 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 35b8eb30 .config console log report ci2-upstream-kcsan-gce
2020/05/03 12:18 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 58ae5e18 .config console log report ci2-upstream-kcsan-gce
2020/05/01 21:13 https://github.com/google/ktsan.git kcsan 7c3cd68e5d38 bc734e7a .config console log report ci2-upstream-kcsan-gce
2019/12/12 18:10 https://github.com/google/ktsan.git kcsan ef798c30ba4e 08003f64 .config console log report ci2-upstream-kcsan-gce
2019/10/23 03:04 https://github.com/google/ktsan.git kcsan 05f2236801fe d0686497 .config console log report ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.