[syzbot] [arm?] WARNING in delayed_work_timer_fn (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 5cbb61bf4168 arm64/fpsimd: ptrace: zero target's fpsimd_st..
git tree: git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux.git for-kernelci
console output: https://syzkaller.appspot.com/x/log.txt?x=10e45a73980000
kernel config: https://syzkaller.appspot.com/x/.config?x=a834c6344141a58b
dashboard link: https://syzkaller.appspot.com/bug?extid=48fc5b35b350240fd465
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8
userspace arch: arm64

Unfortunately, I don't have any reproducer for this issue yet.

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/04156ec16593/disk-5cbb61bf.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/6bfa041e2c79/vmlinux-5cbb61bf.xz
kernel image: https://storage.googleapis.com/syzbot-assets/a92d82d8a79e/Image-5cbb61bf.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+48fc5b...@syzkaller.appspotmail.com

------------[ 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.3.1091/10273
Modules linked in:
CPU: 1 UID: 0 PID: 10273 Comm: syz.3.1091 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: ffff0000c9d69800 x25: 0000000000000008 x24: ffff0000c9d699c0
x23: dfff800000000000 x22: ffff0000db3fba08 x21: 0000000000000100
x20: ffff800089f06000 x19: ffff0000d915ca70 x18: 1fffe00035c25820
x17: ffff8001258ac000 x16: ffff80008e8e0000 x15: 0000000000000000
x14: 0000000000000000 x13: 0000000000000001 x12: 0000000000000000
x11: 0000000000001f53 x10: 0000000000ff0100 x9 : 48aa0a8f34ab2700
x8 : 48aa0a8f34ab2700 x7 : ffff8000804886d0 x6 : 0000000000000000
x5 : 0000000000000001 x4 : 0000000000000000 x3 : ffff8000802f13b0
x2 : 0000000000000101 x1 : ffff0000db3fba00 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
__el1_irq arch/arm64/kernel/entry-common.c:497 [inline]
el1_interrupt+0x40/0x60 arch/arm64/kernel/entry-common.c:509
el1h_64_irq_handler+0x18/0x24 arch/arm64/kernel/entry-common.c:514
el1h_64_irq+0x6c/0x70 arch/arm64/kernel/entry.S:590
__daif_local_irq_restore arch/arm64/include/asm/irqflags.h:175 [inline] (P)
arch_local_irq_restore arch/arm64/include/asm/irqflags.h:195 [inline] (P)
__raw_spin_unlock_irqrestore include/linux/spinlock_api_smp.h:178 [inline] (P)
_raw_spin_unlock_irqrestore+0x44/0x98 kernel/locking/spinlock.c:198 (P)
spin_unlock_irqrestore include/linux/spinlock.h:408 [inline]
__wake_up_common_lock+0x5c/0x78 kernel/sched/wait.c:127
__wake_up_sync_key+0x20/0x2c kernel/sched/wait.c:192
__unix_dgram_recvmsg+0x2bc/0x898 net/unix/af_unix.c:2612
unix_dgram_recvmsg+0xcc/0xe4 net/unix/af_unix.c:2686
sock_recvmsg_nosec+0x90/0xe8 net/socket.c:1137
____sys_recvmsg+0x4f8/0x604 net/socket.c:2916
___sys_recvmsg+0x16c/0x1f4 net/socket.c:2960
do_recvmmsg+0x2a8/0x7e8 net/socket.c:3055
__sys_recvmmsg+0x1e0/0x270 net/socket.c:3129
__do_sys_recvmmsg net/socket.c:3152 [inline]
__se_sys_recvmmsg net/socket.c:3145 [inline]
__arm64_sys_recvmmsg+0xd0/0xf8 net/socket.c:3145
__invoke_syscall arch/arm64/kernel/syscall.c:35 [inline]
invoke_syscall+0x98/0x244 arch/arm64/kernel/syscall.c:49
el0_svc_common+0xe8/0x23c arch/arm64/kernel/syscall.c:121
do_el0_svc+0x48/0x58 arch/arm64/kernel/syscall.c:140
el0_svc+0x60/0x25c arch/arm64/kernel/entry-common.c:723
el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:742
el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594
irq event stamp: 1293
hardirqs last enabled at (1292): [<ffff80008030866c>] handle_softirqs+0x1cc/0xd34 kernel/softirq.c:606
hardirqs last disabled at (1293): [<ffff800086743ef0>] __raw_spin_lock_irq include/linux/spinlock_api_smp.h:140 [inline]
hardirqs last disabled at (1293): [<ffff800086743ef0>] _raw_spin_lock_irq+0x28/0x70 kernel/locking/spinlock.c:174
softirqs last enabled at (24): [<ffff800080139e6c>] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32
softirqs last disabled at (1291): [<ffff8000800204b0>] __do_softirq+0x14/0x20 kernel/softirq.c:656
---[ end trace 0000000000000000 ]---
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available
IPVS: lc: UDP 224.0.0.2:0 - no destination available


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