[v5.15] WARNING in stub_timer

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: b9d57c40a767 Linux 5.15.203
git tree: linux-5.15.y
console output: https://syzkaller.appspot.com/x/log.txt?x=10cc51ba580000
kernel config: https://syzkaller.appspot.com/x/.config?x=353ae28c40b35af5
dashboard link: https://syzkaller.appspot.com/bug?extid=f0e6ad630bae3f8d21a5
compiler: Debian clang version 21.1.8 (++20251221033036+2078da43e25a-1~exp1~20251221153213.50), Debian LLD 21.1.8

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/34313629ba4f/disk-b9d57c40.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/402f526e5a98/vmlinux-b9d57c40.xz
kernel image: https://storage.googleapis.com/syzbot-assets/45f7694e9617/bzImage-b9d57c40.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+f0e6ad...@syzkaller.appspotmail.com

------------[ cut here ]------------
WARNING: CPU: 0 PID: 4211 at kernel/time/timer.c:652 stub_timer+0x5/0x10 kernel/time/timer.c:651
Modules linked in:
CPU: 0 PID: 4211 Comm: kworker/u4:5 Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Workqueue: bat_events batadv_nc_worker
RIP: 0010:stub_timer+0x5/0x10 kernel/time/timer.c:652
Code: 32 96 e8 6e bd ff ff eb 05 e8 77 a6 10 00 83 fb 05 0f 94 c0 5b 41 5e c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 00 e8 5b a6 10 00 <0f> 0b c3 0f 1f 84 00 00 00 00 00 41 57 41 56 41 55 41 54 53 49 89
RSP: 0018:ffffc90000007c58 EFLAGS: 00010246
RAX: ffffffff81688e35 RBX: 0000000000000101 RCX: ffff88806246d940
RDX: 0000000000000100 RSI: ffffffff8a79fe20 RDI: ffffc90000d47bc0
RBP: ffffc90000007d50 R08: ffffffff8d89f06f R09: 1ffffffff1b13e0d
R10: dffffc0000000000 R11: fffffbfff1b13e0e R12: ffffc90000d47bc0
R13: ffffffff81688e30 R14: 1ffff92000000f90 R15: 0000000000000001
FS: 0000000000000000(0000) GS:ffff8880b9000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fd56846af00 CR3: 0000000063695000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<IRQ>
call_timer_fn+0x17b/0x540 kernel/time/timer.c:1648
expire_timers kernel/time/timer.c:1699 [inline]
__run_timers+0x53e/0x800 kernel/time/timer.c:1970
run_timer_softirq+0x63/0xf0 kernel/time/timer.c:1983
handle_softirqs+0x339/0x830 kernel/softirq.c:576
do_softirq+0x142/0x210 kernel/softirq.c:477
</IRQ>
<TASK>
__local_bh_enable_ip+0x180/0x1c0 kernel/softirq.c:401
spin_unlock_bh include/linux/spinlock.h:409 [inline]
batadv_nc_purge_paths+0x316/0x3b0 net/batman-adv/network-coding.c:475
batadv_nc_worker+0x2e7/0x5c0 net/batman-adv/network-coding.c:724
process_one_work+0x85f/0x1010 kernel/workqueue.c:2310
worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457
kthread+0x436/0x520 kernel/kthread.c:334
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287
</TASK>


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