KCSAN: data-race in kick_pool / wq_worker_running

Status: upstream: reported on 2024/11/29 14:38
Subsystems: net
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+f8761b2f358f6a1dec5e@syzkaller.appspotmail.com
First crash: 871d, last: 2h30m
✨ AI Jobs (4)
ID Workflow Result Correct Bug Created Started Finished Revision Error
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
Error 429, Message: You exceeded your current quota, please check your plan and billing details. For more information on this error, head to: https://ai.google.dev/gemini-api/docs/rate-limits. To moni...
truncated to first 200 bytes; open job for full error
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 0xffff888237c2a8e4 of 4 bytes by task 3403 on cpu 0:
 wq_worker_running+0x9b/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_fib4_rt_add drivers/net/netdevsim/fib.c:369 [inline]
 nsim_fib4_rt_insert drivers/net/netdevsim/fib.c:432 [inline]
 nsim_fib4_event drivers/net/netdevsim/fib.c:464 [inline]
 nsim_fib_event+0x4996/0x4dc0 drivers/net/netdevsim/fib.c:884
 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+0x221/0x270 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 0xffff888237c2a8e4 of 4 bytes by task 3376 on cpu 1:
 need_more_worker kernel/workqueue.c:952 [inline]
 kick_pool+0x49/0x2d0 kernel/workqueue.c:1274
 __queue_work+0x8e9/0xb90 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+0x221/0x270 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: 3376 Comm: kworker/1:3 Not tainted syzkaller #0 PREEMPT(lazy) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026
Workqueue: rcu_gp process_srcu
==================================================================

Crashes (1406):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
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
2026/07/23 06:15 upstream 4539944e5151 881ce5c2 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/22 21:40 upstream 4539944e5151 4a865b71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/22 10:52 upstream 248951ddc14d 4a865b71 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/22 00:28 upstream 248951ddc14d b561ce9c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/21 18:12 upstream 248951ddc14d 7c5de9c3 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/20 18:38 upstream 1590cf032971 de6a700d .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/20 01:25 upstream 82a47586c0b9 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/19 18:49 upstream c6859eed755d 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/19 00:09 upstream 1229e2e57a5c 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/18 09:24 upstream 94515f3a7d42 72524a66 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/18 01:18 upstream 111e7b23e5b0 8aaff637 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/17 15:30 upstream fce2dfa773ce 8aaff637 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/17 01:10 upstream 37e2f878a7a6 71b49442 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/16 07:08 upstream 37e2f878a7a6 27a8bd60 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/15 22:12 upstream 58717b2a1365 27a8bd60 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/14 03:15 upstream 3b029c035b34 2130f682 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/13 13:08 upstream a13c140cc289 cc4833d0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/12 21:30 upstream f4fb100039e9 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/12 16:09 upstream 44696aa3a489 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/11 17:43 upstream dd3210c47e8d d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/11 04:44 upstream 61c03dfde854 d78ea535 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/10 09:30 upstream a635d6748234 4167ee25 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/09 10:56 upstream 0e35b9b6ec0f b9f1ceaa .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/08 15:28 upstream 0e35b9b6ec0f 88a4b44c .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/07 14:10 upstream 0e35b9b6ec0f 76cdc0c0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/07 09:37 upstream 0e35b9b6ec0f 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/07 02:20 upstream 8cdeaa50eae8 8e71ce95 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/06 22:50 upstream 8cdeaa50eae8 88b240e4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-kcsan-gce KCSAN: data-race in kick_pool / wq_worker_running
2026/07/06 07:12 upstream 8cdeaa50eae8 fcece630 .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.