syzbot
WARNING in nsim_dev_netdevice_event
Status:
upstream: reported on 2026/10/27 18:35
Subsystems:
net
[Documentation on labels]
Reported-by: syzbot+a104228f8a378b00e6ad@syzkaller.appspotmail.com
First crash: 4d04h, last: 2d02h
▶
▼
Last patch testing requests (1)
Sample crash report:
: left promiscuous mode
P: left promiscuous mode
------------[ cut here ]------------
DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: kernel/locking/mutex.c:625 at __mutex_lock_common kernel/locking/mutex.c:625 [inline], CPU#1: kworker/u8:3/50
WARNING: kernel/locking/mutex.c:625 at __mutex_lock+0x132a/0x15a0 kernel/locking/mutex.c:821, CPU#1: kworker/u8:3/50
Modules linked in:
CPU: 1 UID: 0 PID: 50 Comm: kworker/u8:3 Tainted: G L syzkaller #0 PREEMPT(full)
Tainted: [L]=SOFTLOCKUP
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026
Workqueue: netns cleanup_net
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:625 [inline]
RIP: 0010:__mutex_lock+0x1331/0x15a0 kernel/locking/mutex.c:821
Code: 23 9d 91 48 c1 e8 03 0f b6 04 18 84 c0 0f 85 46 02 00 00 83 3d 43 35 9e 05 00 75 13 48 8d 3d a6 34 a1 05 48 c7 c6 e0 27 2d 8c <67> 48 0f b9 3a 90 e9 1d ee ff ff 90 0f 0b 90 e9 f0 f1 ff ff 90 0f
RSP: 0018:ffffc90000ba7040 EFLAGS: 00010246
RAX: 0000000000000000 RBX: dffffc0000000000 RCX: ffff888021a8be80
RDX: 0000000000000000 RSI: ffffffff8c2d27e0 RDI: ffffffff91a02350
RBP: ffffc90000ba71c8 R08: ffffffff919d23e3 R09: 1ffffffff233a47c
R10: dffffc0000000000 R11: fffffbfff233a47d R12: ffff88807c371500
R13: 0000000000000000 R14: 1ffff92000174e1c R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88812373c000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fb6d95f62f8 CR3: 00000000361d6000 CR4: 00000000003526f0
Call Trace:
<TASK>
nsim_dev_hwstats_event_unregister drivers/net/netdevsim/hwstats.c:174 [inline]
nsim_dev_hwstats_event drivers/net/netdevsim/hwstats.c:192 [inline]
nsim_dev_netdevice_event+0x1e8/0x830 drivers/net/netdevsim/hwstats.c:207
notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:86
call_netdevice_notifiers_info+0x8c/0x100 net/core/dev.c:2310
call_netdevice_notifiers_extack net/core/dev.c:2351 [inline]
call_netdevice_notifiers net/core/dev.c:2365 [inline]
unregister_netdevice_many_notify+0x1432/0x1d80 net/core/dev.c:12697
unregister_netdevice_many net/core/dev.c:12768 [inline]
unregister_netdevice_queue+0x2f5/0x340 net/core/dev.c:12564
unregister_netdevice include/linux/netdevice.h:3509 [inline]
_cfg80211_unregister_wdev+0x1c4/0x8e0 net/wireless/core.c:1503
ieee80211_remove_interfaces+0x49c/0x6a0 net/mac80211/iface.c:2528
ieee80211_unregister_hw+0x5d/0x2d0 net/mac80211/main.c:1725
mac80211_hwsim_del_radio+0x31a/0x500 drivers/net/wireless/virtual/mac80211_hwsim_main.c:6302
hwsim_exit_net+0xe91/0xf50 drivers/net/wireless/virtual/mac80211_hwsim_main.c:7365
ops_exit_list net/core/net_namespace.c:200 [inline]
ops_undo_list+0x451/0x8f0 net/core/net_namespace.c:253
cleanup_net+0x572/0x810 net/core/net_namespace.c:706
process_one_work kernel/workqueue.c:3495 [inline]
process_scheduled_works+0xc3d/0x1630 kernel/workqueue.c:3578
worker_thread+0xa47/0xfb0 kernel/workqueue.c:3659
kthread+0x38b/0x480 kernel/kthread.c:436
ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158
ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
</TASK>
----------------
Code disassembly (best guess):
0: 23 9d 91 48 c1 e8 and -0x173eb76f(%rbp),%ebx
6: 03 0f add (%rdi),%ecx
8: b6 04 mov $0x4,%dh
a: 18 84 c0 0f 85 46 02 sbb %al,0x246850f(%rax,%rax,8)
11: 00 00 add %al,(%rax)
13: 83 3d 43 35 9e 05 00 cmpl $0x0,0x59e3543(%rip) # 0x59e355d
1a: 75 13 jne 0x2f
1c: 48 8d 3d a6 34 a1 05 lea 0x5a134a6(%rip),%rdi # 0x5a134c9
23: 48 c7 c6 e0 27 2d 8c mov $0xffffffff8c2d27e0,%rsi
* 2a: 67 48 0f b9 3a ud1 (%edx),%rdi <-- trapping instruction
2f: 90 nop
30: e9 1d ee ff ff jmp 0xffffee52
35: 90 nop
36: 0f 0b ud2
38: 90 nop
39: e9 f0 f1 ff ff jmp 0xfffff22e
3e: 90 nop
3f: 0f .byte 0xf
* Struck through repros no longer work on HEAD.