KCSAN: data-race in kick_pool / wq_worker_running

Status: upstream: reported on 2024/11/29 14:38
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+f8761b2f358f6a1dec5e@syzkaller.appspotmail.com
First crash: 900d, last: 8d17h
✨ AI Jobs (4)
ID Workflow Result Correct Bug Created Started Finished Revision
1814e531 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ✅ NetworkTrigger: ✅ PeripheralTrigger: ✅ RemoteTrigger: ✅ Unprivileged: ✅ UserNamespace: ✅ VMGuestTrigger: ✅ VMHostTrigger: ✅ KCSAN: data-race in kick_pool / wq_worker_running 2026/05/15 09:20 2026/05/15 09:20 2026/05/15 09:47 9cd3beaa
d5fc201b repro KCSAN: data-race in kick_pool / wq_worker_running 2026/03/07 08:34 2026/03/07 08:34 2026/03/07 08:37 31e9c887
5e4bacfd assessment-kcsan Benign: ✅ Confident: ✅ KCSAN: data-race in kick_pool / wq_worker_running 2026/02/24 19:11 2026/02/24 19:11 2026/02/24 19:14 305c0ec5
07cfd40a assessment-kcsan 💥 KCSAN: data-race in kick_pool / wq_worker_running 2026/01/10 00:02 2026/01/10 00:02 2026/01/10 00:02 75199160
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [kernel?] KCSAN: data-race in kick_pool / wq_worker_running 1 (2) 2024/11/29 23:58

Sample crash report:
==================================================================
BUG: KCSAN: data-race in kick_pool / wq_worker_running

read-write to 0xffff888237c2aa24 of 4 bytes by task 5532 on cpu 0:
 wq_worker_running+0x9c/0x120 kernel/workqueue.c:1434
 schedule_timeout+0xca/0x180 kernel/time/sleep_timeout.c:99
 schedule_timeout_uninterruptible kernel/time/sleep_timeout.c:158 [inline]
 msleep+0x4f/0x90 kernel/time/sleep_timeout.c:318
 nsim_fib6_rt_add drivers/net/netdevsim/fib.c:693 [inline]
 nsim_fib6_rt_insert drivers/net/netdevsim/fib.c:759 [inline]
 nsim_fib6_event drivers/net/netdevsim/fib.c:856 [inline]
 nsim_fib_event+0x4544/0x4de0 drivers/net/netdevsim/fib.c:889
 nsim_fib_event_work+0x133/0x200 drivers/net/netdevsim/fib.c:1493
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

read to 0xffff888237c2aa24 of 4 bytes by task 3415 on cpu 1:
 need_more_worker kernel/workqueue.c:952 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1274
 __queue_work+0x8de/0xb90 kernel/workqueue.c:2402
 queue_work_on+0xa9/0x140 kernel/workqueue.c:2452
 srcu_queue_delayed_work_on kernel/rcu/srcutree.c:873 [inline]
 srcu_schedule_cbs_sdp kernel/rcu/srcutree.c:886 [inline]
 srcu_gp_end kernel/rcu/srcutree.c:951 [inline]
 srcu_advance_state kernel/rcu/srcutree.c:1869 [inline]
 process_srcu+0xa39/0xd90 kernel/rcu/srcutree.c:1973
 process_one_work kernel/workqueue.c:3322 [inline]
 process_scheduled_works+0x4d4/0x9a0 kernel/workqueue.c:3405
 worker_thread+0x569/0x750 kernel/workqueue.c:3486
 kthread+0x223/0x270 kernel/kthread.c:436
 ret_from_fork+0x146/0x330 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 3415 Comm: kworker/1:6 Tainted: G        W           syzkaller #0 PREEMPT(lazy) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: rcu_gp process_srcu
==================================================================

Crashes (1432):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/08/20 18:28 upstream a4ff2be345d0 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/19 20:49 upstream e8bf40d15402 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/18 10:15 upstream ff68e5f557f6 1e72964b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/17 22:11 upstream 8d3ae59288f1 905244d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/16 19:14 upstream dcb68831eac7 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/16 05:26 upstream 3eb40771c00a 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/15 12:18 upstream dac3e89a2c90 746171ee .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/14 00:28 upstream 3aa1dcaa4f6f b13552fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/12 18:52 upstream 3d6d817622b0 359b2492 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/11 21:39 upstream f5bbbfec59b4 71790083 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/10 05:10 upstream b9b3e33b70b7 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/09 15:41 upstream 06cf61899d64 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/09 04:40 upstream a7c7074b58d2 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/08 06:34 upstream bcc44b6785f2 5d63f80b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/08 00:22 upstream bcc44b6785f2 e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/07 11:50 upstream f9a2394a2348 e4ef95d6 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/07 05:20 upstream fcaeecb8b0cd c38879ea .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/05 17:46 upstream 0d8395707651 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/05 08:39 upstream c21bb4193868 52aa2820 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/04 19:15 upstream 562bfb501c54 d4abbeac .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/03 14:42 upstream 075b74841bd0 6b7c9f71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/02 21:49 upstream bd1dde877520 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/02 08:05 upstream 2d2338c93da7 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/01 23:56 upstream 02dc699f83d0 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/08/01 14:20 upstream 0131b508c0e2 e611ffe1 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/31 12:14 upstream 8ba098e6b6ff aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/31 02:17 upstream 3708dd948844 aaffb173 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/29 04:32 upstream fc02acf6ac0c 19622d9d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/28 18:26 upstream 3b5f4b83c4ab edc8a875 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/28 16:50 upstream 62cc90241548 edc8a875 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/28 02:51 upstream 62cc90241548 45ae1df4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/27 16:30 upstream f5098b6bae76 aae9036b .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/27 10:27 upstream f5098b6bae76 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/27 05:03 upstream 4235cb24ec1e 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/26 13:45 upstream 3dab139d4795 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/26 06:47 upstream 3dab139d4795 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/26 02:58 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/25 17:43 upstream 0ce37745d4bf 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/25 04:25 upstream e2a936998ab2 492bab15 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/24 14:05 upstream 48a5a7ab8d6a dd737a83 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/24 07:00 upstream d326f83e819c 544adce9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/23 20:49 upstream d326f83e819c 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/23 12:43 upstream 4539944e5151 71a13572 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/05/14 00:34 upstream e1914add2799 6ccb967e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/03/06 19:55 upstream 651690480a96 41d8037d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/02/24 14:31 upstream 7dff99b35460 96b1aa46 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/01/09 23:46 upstream 372800cb95a3 d6526ea3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2024/11/28 22:51 upstream 7af08b57bcb9 5df23865 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2024/11/19 01:21 upstream 23acd177540d 571351cb .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
* Struck through repros no longer work on HEAD.