WARNING in rcu_tasks_verify_work_fn

Status: upstream: reported on 2026/03/31 21:53
Subsystems: kernel
Labels: prio:low
[Documentation on labels]
Reported-by: syzbot+251e9abcdac140e7ec74@syzkaller.appspotmail.com
First crash: 195d, last: 17h18m
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ID Workflow Result Correct Bug Created Started Finished Revision
f65ca737 assessment-security DenialOfService: ❌ Exploitable: ❌ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌ ❓ WARNING in rcu_tasks_verify_work_fn 2026/05/26 01:24 2026/05/26 01:24 2026/05/26 01:51 c69befb3
▶ ▼ Discussions (4)
Title Replies (including bot) Last reply
[PATCH AUTOSEL 6.18-5.10] wifi: cfg80211: validate IEs in cfg80211_wext_siwgenie() 8 (8) 2026/08/31 13:30
[PATCH] rcu-tasks: Dump rcu tasks status when the boot-test failed 1 (1) 2026/07/06 10:03
[PATCH] rcu-tasks: Fix possible boot-time tests failed for the call_rcu_tasks() 1 (1) 2026/04/23 11:19
[syzbot] [kernel?] WARNING in rcu_tasks_verify_work_fn 0 (1) 2026/03/31 21:53

Sample crash report:
call_rcu_tasks() has failed boot-time tests.
rcu_tasks: RTGS_WAIT_SCAN_HOLDOUTS(6) since 8 g:5 i:0 kCuUP l:25 
------------[ cut here ]------------
ret < 0
WARNING: kernel/rcu/tasks.h:1541 at rcu_tasks_verify_self_tests kernel/rcu/tasks.h:1541 [inline], CPU#1: kworker/1:2/883
WARNING: kernel/rcu/tasks.h:1541 at rcu_tasks_verify_work_fn+0x1b6/0x270 kernel/rcu/tasks.h:1553, CPU#1: kworker/1:2/883
Modules linked in:
CPU: 1 UID: 0 PID: 883 Comm: kworker/1:2 Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026
Workqueue: events rcu_tasks_verify_work_fn
RIP: 0010:rcu_tasks_verify_self_tests kernel/rcu/tasks.h:1541 [inline]
RIP: 0010:rcu_tasks_verify_work_fn+0x1b6/0x270 kernel/rcu/tasks.h:1553
Code: 80 3c 10 00 0f 85 b5 00 00 00 48 8b 35 cb 3a 77 0c b9 64 00 00 00 bf 08 00 00 00 48 c7 c2 a0 da 9a 9b e8 ad 4e e2 ff eb 97 90 <0f> 0b 90 eb 91 48 89 df e8 ad e7 8f 00 e9 69 ff ff ff 48 89 df e8
RSP: 0018:ffffc900042f7bb0 EFLAGS: 00010246
RAX: 0000000000000000 RBX: ffffffff8edebc28 RCX: 0000000000000000
RDX: 1ffffffff1dbd785 RSI: ffffffff81ea18b9 RDI: fffff5200085ef49
RBP: 1ffff9200085ef76 R08: 0000000000000007 R09: 0000000000000000
R10: 8000000000000000 R11: 0000000000000001 R12: 0000000000000bb8
R13: 00000000ffffffff R14: 0000000000000001 R15: ffffffff8edebc28
FS:  0000000000000000(0000) GS:ffff888123c4b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000000 CR3: 000000000eb96000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 process_one_work+0xac7/0x1b10 kernel/workqueue.c:3396
 process_scheduled_works kernel/workqueue.c:3479 [inline]
 worker_thread+0x5ef/0xe50 kernel/workqueue.c:3560
 kthread+0x373/0x450 kernel/kthread.c:436
 ret_from_fork+0x730/0xd60 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Crashes (857):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/10/08 22:58 upstream 7b63ef2d55f2 b2734a59 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/08 17:09 upstream 7b63ef2d55f2 4f6a9fcf .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/08 09:03 upstream 7b63ef2d55f2 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/07 20:45 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 19:36 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 18:11 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 16:15 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 13:36 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 12:28 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 11:00 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 10:23 upstream 602042bf29f6 6520ecdb .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 08:34 upstream 602042bf29f6 f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/07 01:55 upstream 69f80fef3153 f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/07 00:37 upstream 22430ae5d90a f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 22:45 upstream 22430ae5d90a f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 21:26 upstream 22430ae5d90a f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 19:22 upstream 22430ae5d90a f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 17:09 upstream 22430ae5d90a f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 15:59 upstream 22430ae5d90a f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 14:22 upstream 2c3418fffa9d f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/06 12:21 upstream 67f0943b394d f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 10:59 upstream 2c3418fffa9d f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/06 08:21 upstream 67f0943b394d f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 06:53 upstream 67f0943b394d f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/06 05:21 upstream 67f0943b394d f7710056 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/05 21:21 upstream a90ee4305c4a 1995e6c7 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/05 19:41 upstream a90ee4305c4a 1995e6c7 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/05 17:15 upstream a90ee4305c4a 1995e6c7 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/05 16:04 upstream a90ee4305c4a 1995e6c7 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/05 08:51 upstream 7704c4c5bb12 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/05 05:20 upstream a90ee4305c4a 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/04 22:41 upstream 7704c4c5bb12 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 20:59 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/04 18:32 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/04 15:54 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 14:11 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 11:29 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 09:47 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 06:10 upstream 6addb4f38557 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 05:08 upstream 8623551a424d 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/04 00:18 upstream a74306e2e676 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/03 22:40 upstream a74306e2e676 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/03 21:08 upstream a74306e2e676 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/03 18:13 upstream 8623551a424d 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/10/03 15:11 upstream e767a4ea70a3 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-upstream-kasan-badwrites-root WARNING in rcu_tasks_verify_work_fn
2026/10/03 13:58 upstream ff47652a4b66 57bbd979 .config console log report [disk image] [vmlinux] [kernel image] ci-qemu-gce-upstream-auto WARNING in rcu_tasks_verify_work_fn
2026/06/25 12:48 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next 319fafd9a374 432fd51a .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
2026/04/27 05:43 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next 9b3a2be84803 9c2d0995 .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
2026/03/27 22:12 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next b335bc5892a0 158c21af .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
2026/03/27 21:42 git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux.git for-next b335bc5892a0 158c21af .config console log report [disk image (non-bootable)] [vmlinux] [kernel image] ci-qemu2-riscv64 WARNING in rcu_tasks_verify_work_fn
* Struck through repros no longer work on HEAD.