[v6.1] INFO: task hung in linkwatch_event (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 4078fa637fcd Linux 6.1.91
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=172b00ec980000
kernel config: https://syzkaller.appspot.com/x/.config?x=715ba80acfd3def4
dashboard link: https://syzkaller.appspot.com/bug?extid=cf14cd499f4c01714644
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/2443dfe91c62/disk-4078fa63.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/12dbc2af3348/vmlinux-4078fa63.xz
kernel image: https://storage.googleapis.com/syzbot-assets/da3589238e32/bzImage-4078fa63.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+cf14cd...@syzkaller.appspotmail.com

INFO: task kworker/0:4:3579 blocked for more than 143 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:4 state:D stack:23136 pid:3579 ppid:2 flags:0x00004000
Workqueue: events linkwatch_event
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
linkwatch_event+0xa/0x50 net/core/link_watch.c:263
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
process_scheduled_works kernel/workqueue.c:2355 [inline]
worker_thread+0xd04/0x1200 kernel/workqueue.c:2441
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
INFO: task syz-executor.4:3599 blocked for more than 143 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.4 state:D stack:20632 pid:3599 ppid:1 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
rtnl_lock net/core/rtnetlink.c:74 [inline]
rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x480/0x600 net/socket.c:2148
__do_sys_sendto net/socket.c:2160 [inline]
__se_sys_sendto net/socket.c:2156 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2156
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fdc3807ebdc
RSP: 002b:00007ffe2587bdd0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fdc38cd4620 RCX: 00007fdc3807ebdc
RDX: 0000000000000028 RSI: 00007fdc38cd4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffe2587be24 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fdc38cd4670 R15: 0000000000000000
</TASK>
INFO: task syz-executor.2:3601 blocked for more than 143 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.2 state:D stack:21176 pid:3601 ppid:1 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
rtnl_lock net/core/rtnetlink.c:74 [inline]
rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x480/0x600 net/socket.c:2148
__do_sys_sendto net/socket.c:2160 [inline]
__se_sys_sendto net/socket.c:2156 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2156
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa89d67ebdc
RSP: 002b:00007ffc36047c70 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa89e2d4620 RCX: 00007fa89d67ebdc
RDX: 000000000000002c RSI: 00007fa89e2d4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007ffc36047cc4 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fa89e2d4670 R15: 0000000000000000
</TASK>
INFO: task syz-executor.1:3603 blocked for more than 144 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.1 state:D stack:20832 pid:3603 ppid:1 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
devinet_ioctl+0x2a5/0x1b20 net/ipv4/devinet.c:1070
inet_ioctl+0x32d/0x400 net/ipv4/af_inet.c:1006
sock_do_ioctl+0x152/0x450 net/socket.c:1204
sock_ioctl+0x47f/0x770 net/socket.c:1321
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:870 [inline]
__se_sys_ioctl+0xf1/0x160 fs/ioctl.c:856
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7f3277c7cc4b
RSP: 002b:00007ffc305dcc20 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007ffc305dcd40 RCX: 00007f3277c7cc4b
RDX: 00007ffc305dcca0 RSI: 0000000000008914 RDI: 0000000000000005
RBP: 0000000000000005 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000022
R13: 0000000000000047 R14: 00007f32788d4620 R15: 00007ffc305dcca0
</TASK>
INFO: task syz-executor.3:3606 blocked for more than 144 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor.3 state:D stack:21112 pid:3606 ppid:1 flags:0x00004006
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
rtnl_lock net/core/rtnetlink.c:74 [inline]
rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
netlink_rcv_skb+0x1cd/0x410 net/netlink/af_netlink.c:2508
netlink_unicast_kernel net/netlink/af_netlink.c:1326 [inline]
netlink_unicast+0x7d8/0x970 net/netlink/af_netlink.c:1352
netlink_sendmsg+0xa26/0xd60 net/netlink/af_netlink.c:1874
sock_sendmsg_nosec net/socket.c:718 [inline]
__sock_sendmsg net/socket.c:730 [inline]
__sys_sendto+0x480/0x600 net/socket.c:2148
__do_sys_sendto net/socket.c:2160 [inline]
__se_sys_sendto net/socket.c:2156 [inline]
__x64_sys_sendto+0xda/0xf0 net/socket.c:2156
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3b/0xb0 arch/x86/entry/common.c:81
entry_SYSCALL_64_after_hwframe+0x68/0xd2
RIP: 0033:0x7fa4dde7ebdc
RSP: 002b:00007fff0f6c9ab0 EFLAGS: 00000293 ORIG_RAX: 000000000000002c
RAX: ffffffffffffffda RBX: 00007fa4dead4620 RCX: 00007fa4dde7ebdc
RDX: 000000000000002c RSI: 00007fa4dead4670 RDI: 0000000000000003
RBP: 0000000000000000 R08: 00007fff0f6c9b04 R09: 000000000000000c
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000003
R13: 0000000000000000 R14: 00007fa4dead4670 R15: 0000000000000000
</TASK>
INFO: task kworker/1:6:3657 blocked for more than 144 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/1:6 state:D stack:22528 pid:3657 ppid:2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4114
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
INFO: task kworker/0:8:3658 blocked for more than 145 seconds.
Not tainted 6.1.91-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/0:8 state:D stack:24120 pid:3658 ppid:2 flags:0x00004000
Workqueue: ipv6_addrconf addrconf_dad_work
Call Trace:
<TASK>
context_switch kernel/sched/core.c:5245 [inline]
__schedule+0x142d/0x4550 kernel/sched/core.c:6558
schedule+0xbf/0x180 kernel/sched/core.c:6634
schedule_preempt_disabled+0xf/0x20 kernel/sched/core.c:6693
__mutex_lock_common kernel/locking/mutex.c:679 [inline]
__mutex_lock+0x6b9/0xd80 kernel/locking/mutex.c:747
addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4114
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
#0: ffffffff8d12ae50 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
1 lock held by rcu_tasks_trace/13:
#0: ffffffff8d12b650 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x29/0xe30 kernel/rcu/tasks.h:516
3 locks held by kworker/0:1/14:
#0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90000137d20 ((work_completion)(&fw_work->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: regdb_fw_cb+0x7e/0x1b0 net/wireless/reg.c:1053
1 lock held by khungtaskd/28:
#0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:350 [inline]
#0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:791 [inline]
#0: ffffffff8d12ac80 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x51/0x290 kernel/locking/lockdep.c:6494
3 locks held by kworker/1:2/2962:
#0: ffff888012471938 ((wq_completion)events_power_efficient){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc9000dab7d20 ((reg_check_chans).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: reg_check_chans_work+0x8d/0xdb0 net/wireless/reg.c:2498
2 locks held by getty/3302:
#0: ffff888014e5c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x21/0x70 drivers/tty/tty_ldisc.c:244
#1: ffffc900031262f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6a7/0x1db0 drivers/tty/n_tty.c:2188
3 locks held by kworker/0:4/3579:
#0: ffff888012470938 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc9000464fd20 ((linkwatch_work).work){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: linkwatch_event+0xa/0x50 net/core/link_watch.c:263
1 lock held by syz-executor.4/3599:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.2/3601:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.1/3603:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: devinet_ioctl+0x2a5/0x1b20 net/ipv4/devinet.c:1070
1 lock held by syz-executor.3/3606:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
3 locks held by kworker/1:6/3657:
#0: ffff888028f25938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90004bffd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4114
3 locks held by kworker/0:8/3658:
#0: ffff888028f25938 ((wq_completion)ipv6_addrconf){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#1: ffffc90004c0fd20 ((work_completion)(&(&ifa->dad_work)->work)){+.+.}-{0:0}, at: process_one_work+0x7a9/0x11d0 kernel/workqueue.c:2267
#2: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: addrconf_dad_work+0xcc/0x16b0 net/ipv6/addrconf.c:4114
1 lock held by syz-executor.0/3691:
1 lock held by syz-executor.0/3694:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.1/3708:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.3/3709:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.4/3714:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.2/3715:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.0/3722:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.3/3731:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.4/3734:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.2/3736:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118
1 lock held by syz-executor.1/3739:
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnl_lock net/core/rtnetlink.c:74 [inline]
#0: ffffffff8e29af28 (rtnl_mutex){+.+.}-{3:3}, at: rtnetlink_rcv_msg+0x7c1/0xff0 net/core/rtnetlink.c:6118

=============================================

NMI backtrace for cpu 0
CPU: 0 PID: 28 Comm: khungtaskd Not tainted 6.1.91-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e3/0x2cb lib/dump_stack.c:106
nmi_cpu_backtrace+0x4e1/0x560 lib/nmi_backtrace.c:111
nmi_trigger_cpumask_backtrace+0x1b0/0x3f0 lib/nmi_backtrace.c:62
trigger_all_cpu_backtrace include/linux/nmi.h:148 [inline]
check_hung_uninterruptible_tasks kernel/hung_task.c:220 [inline]
watchdog+0xf88/0xfd0 kernel/hung_task.c:377
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 PID: 26 Comm: kworker/1:1 Not tainted 6.1.91-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/02/2024
Workqueue: events_power_efficient wg_ratelimiter_gc_entries
RIP: 0010:preempt_count arch/x86/include/asm/preempt.h:27 [inline]
RIP: 0010:check_preemption_disabled+0x20/0x110 lib/smp_processor_id.c:16
Code: 8b 48 c7 c6 40 45 3d 8b eb 00 41 57 41 56 41 54 53 48 83 ec 10 65 48 8b 04 25 28 00 00 00 48 89 44 24 08 65 8b 1d 10 19 77 75 <65> 8b 05 b1 6e 77 75 a9 ff ff ff 7f 74 22 65 48 8b 04 25 28 00 00
RSP: 0018:ffffc90000a1fa88 EFLAGS: 00000086
RAX: ffacc908d54b1b00 RBX: 0000000000000001 RCX: ffffffff816a8827
RDX: 0000000000000000 RSI: ffffffff8aec0ea0 RDI: ffffffff8b3d4560
RBP: ffffc90000a1fbe8 R08: dffffc0000000000 R09: fffffbfff1ce710e
R10: 0000000000000000 R11: dffffc0000000001 R12: 1ffff92000143f64
R13: 0000000000000246 R14: ffffc90000a1fb70 R15: dffffc0000000000
FS: 0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000055ef678f5030 CR3: 0000000028953000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
<NMI>
</NMI>
<TASK>
lockdep_recursion_inc kernel/locking/lockdep.c:462 [inline]
lock_release+0x19e/0xa20 kernel/locking/lockdep.c:5681
__raw_spin_unlock include/linux/spinlock_api_smp.h:141 [inline]
_raw_spin_unlock+0x12/0x40 kernel/locking/spinlock.c:186
spin_unlock include/linux/spinlock.h:391 [inline]
wg_ratelimiter_gc_entries+0x3a7/0x470 drivers/net/wireguard/ratelimiter.c:76
process_one_work+0x8a9/0x11d0 kernel/workqueue.c:2292
worker_thread+0xa47/0x1200 kernel/workqueue.c:2439
kthread+0x28d/0x320 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
</TASK>


---
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