syzbot


WARNING in delayed_work_timer_fn (2)

Status: upstream: reported on 2026/05/12 02:53
Subsystems: arm
[Documentation on labels]
Reported-by: syzbot+48fc5b35b350240fd465@syzkaller.appspotmail.com
First crash: 5d03h, last: 1d00h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [arm?] WARNING in delayed_work_timer_fn (2) 0 (1) 2026/05/12 02:53
Similar bugs (4)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in delayed_work_timer_fn arm -1 syz 312 96d 1055d 0/29 auto-obsoleted due to no activity on 2026/04/16 12:39
linux-6.1 WARNING in delayed_work_timer_fn (2) -1 35 403d 883d 0/3 auto-obsoleted due to no activity on 2025/07/13 12:01
linux-6.1 WARNING in delayed_work_timer_fn -1 2 1022d 1125d 0/3 auto-obsoleted due to no activity on 2023/11/02 17:34
linux-6.1 WARNING in delayed_work_timer_fn (3) -1 6 45d 270d 0/3 upstream: reported on 2025/08/15 19:10

Sample crash report:
------------[ cut here ]------------
workqueue: cannot queue hci_cmd_timeout on wq hci4
WARNING: kernel/workqueue.c:2298 at __queue_work+0xf6c/0x12f8 kernel/workqueue.c:2296, CPU#1: syz.3.690/7994
Modules linked in:
CPU: 1 UID: 0 PID: 7994 Comm: syz.3.690 Tainted: G             L      syzkaller #0 PREEMPT 
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
pstate: 634000c5 (nZCv daIF +PAN -UAO +TCO +DIT -SSBS BTYPE=--)
pc : __queue_work+0xf6c/0x12f8 kernel/workqueue.c:2296
lr : __queue_work+0xf6c/0x12f8 kernel/workqueue.c:2296
sp : ffff80008e8e7b10
x29: ffff80008e8e7b50 x28: dfff800000000000 x27: ffff700011d1cf84
x26: ffff0000dda81000 x25: 0000000000000008 x24: ffff0000dda811c0
x23: dfff800000000000 x22: ffff0000cdd09d08 x21: 0000000000000100
x20: ffff800089f06000 x19: ffff0000fd28ca70 x18: 0000000000000000
x17: ffff8001258ac000 x16: ffff80008e8e0000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000000000 x10: 0000000000ff0100 x9 : f37706269867f700
x8 : f37706269867f700 x7 : ffff8000804886d0 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000000 x3 : ffff8000802f13b0
x2 : 0000000100000100 x1 : ffff0000cdd09d00 x0 : 0000000000000000
Call trace:
 __queue_work+0xf6c/0x12f8 kernel/workqueue.c:2296 (P)
 delayed_work_timer_fn+0x74/0x90 kernel/workqueue.c:2527
 call_timer_fn+0x19c/0xa4c kernel/time/timer.c:1748
 expire_timers kernel/time/timer.c:1794 [inline]
 __run_timers kernel/time/timer.c:2374 [inline]
 __run_timer_base+0x554/0x74c kernel/time/timer.c:2386
 run_timer_base+0x84/0x1b8 kernel/time/timer.c:2395
 run_timer_softirq+0x20/0x48 kernel/time/timer.c:2405
 handle_softirqs+0x2e4/0xd34 kernel/softirq.c:622
 __do_softirq+0x14/0x20 kernel/softirq.c:656
 ____do_softirq+0x14/0x20 arch/arm64/kernel/irq.c:68
 call_on_irq_stack+0x30/0x48 arch/arm64/kernel/entry.S:889
 do_softirq_own_stack+0x20/0x2c arch/arm64/kernel/irq.c:73
 invoke_softirq kernel/softirq.c:503 [inline]
 __irq_exit_rcu+0x1ac/0x428 kernel/softirq.c:735
 irq_exit_rcu+0x14/0x84 kernel/softirq.c:752
 el0_interrupt+0x74/0x2ac arch/arm64/kernel/entry-common.c:816
 __el0_irq_handler_common+0x18/0x24 arch/arm64/kernel/entry-common.c:823
 el0t_64_irq_handler+0x10/0x1c arch/arm64/kernel/entry-common.c:828
 el0t_64_irq+0x198/0x19c arch/arm64/kernel/entry.S:595
irq event stamp: 2045
hardirqs last  enabled at (2044): [<ffff800086744048>] __raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline]
hardirqs last  enabled at (2044): [<ffff800086744048>] _raw_spin_unlock_irqrestore+0x38/0x98 kernel/locking/spinlock.c:198
hardirqs last disabled at (2045): [<ffff800086743ef0>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:140 [inline]
hardirqs last disabled at (2045): [<ffff800086743ef0>] _raw_spin_lock_irq+0x28/0x70 kernel/locking/spinlock.c:174
softirqs last  enabled at (1958): [<ffff800080139e6c>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (1965): [<ffff8000800204b0>] __do_softirq+0x14/0x20 kernel/softirq.c:656
---[ end trace 0000000000000000 ]---

Crashes (5):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/05/12 06:28 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5cbb61bf4168 d168f260 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in delayed_work_timer_fn
2026/05/11 04:44 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5cbb61bf4168 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in delayed_work_timer_fn
2026/05/10 08:14 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5cbb61bf4168 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in delayed_work_timer_fn
2026/05/09 18:04 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5cbb61bf4168 29233ece .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in delayed_work_timer_fn
2026/05/08 02:49 git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci 5cbb61bf4168 e358bca5 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-gce-arm64 WARNING in delayed_work_timer_fn
* Struck through repros no longer work on HEAD.