WARNING in stub_timer

Status: auto-obsoleted due to no activity on 2026/07/30 11:32
Reported-by: syzbot+f0e6ad630bae3f8d21a5@syzkaller.appspotmail.com
First crash: 105d, last: 105d
▶ ▼ Similar bugs (2)
Kernel Title Rank 🛈 Repro Cause bisect Fix bisect Count Last Reported Patched Status
upstream WARNING in stub_timer (2) prio:high kernel -1 1 54d 50d 29/29 fixed on 2026/07/15 08:27
upstream WARNING in stub_timer kernel prio:normal -1 209 155d 208d 0/29 auto-obsoleted due to no activity on 2026/05/28 02:15

Sample crash report:
------------[ 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>

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2026/04/21 11:31 linux-5.15.y b9d57c40a767 3f2e655b .config console log report info [disk image] [vmlinux] [kernel image] ci2-linux-5-15-kasan WARNING in stub_timer
* Struck through repros no longer work on HEAD.