[v6.1] BUG: soft lockup in ser_release

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 3dfebb87d7eb Linux 6.1.133
git tree: linux-6.1.y
console output: https://syzkaller.appspot.com/x/log.txt?x=164a67e4580000
kernel config: https://syzkaller.appspot.com/x/.config?x=ce52a2aea9a41077
dashboard link: https://syzkaller.appspot.com/bug?extid=70d8dc87497ea8a62519
compiler: Debian clang version 15.0.6, GNU ld (GNU Binutils for Debian) 2.40
userspace arch: arm64

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

Downloadable assets:
disk image: https://storage.googleapis.com/syzbot-assets/4039b1bf1518/disk-3dfebb87.raw.xz
vmlinux: https://storage.googleapis.com/syzbot-assets/b3bed498c59c/vmlinux-3dfebb87.xz
kernel image: https://storage.googleapis.com/syzbot-assets/fbe9382a4f24/Image-3dfebb87.gz.xz

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+70d8dc...@syzkaller.appspotmail.com

watchdog: BUG: soft lockup - CPU#0 stuck for 22s! [kworker/0:3:4342]
Modules linked in:
irq event stamp: 170235
hardirqs last enabled at (170234): [<ffff800012326da0>] __exit_to_kernel_mode arch/arm64/kernel/entry-common.c:84 [inline]
hardirqs last enabled at (170234): [<ffff800012326da0>] exit_to_kernel_mode+0xe8/0x118 arch/arm64/kernel/entry-common.c:94
hardirqs last disabled at (170235): [<ffff800012324a7c>] __el1_irq arch/arm64/kernel/entry-common.c:468 [inline]
hardirqs last disabled at (170235): [<ffff800012324a7c>] el1_interrupt+0x24/0x68 arch/arm64/kernel/entry-common.c:486
softirqs last enabled at (166046): [<ffff800010fa06a8>] spin_unlock_bh include/linux/spinlock.h:396 [inline]
softirqs last enabled at (166046): [<ffff800010fa06a8>] clusterip_netdev_event+0x380/0x3a8 net/ipv4/netfilter/ipt_CLUSTERIP.c:233
softirqs last disabled at (166048): [<ffff8000107a0968>] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19
CPU: 0 PID: 4342 Comm: kworker/0:3 Not tainted 6.1.133-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025
Workqueue: events ser_release
pstate: 00400005 (nzcv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--)
pc : queued_spin_lock_slowpath+0x15c/0xe48 kernel/locking/qspinlock.c:383
lr : queued_spin_lock_slowpath+0x168/0xe48 kernel/locking/qspinlock.c:383
sp : ffff800021427560
x29: ffff800021427600 x28: 1fffe0001a557118 x27: 1ffff00004284eb8
x26: dfff800000000000 x25: 1fffe0001a55711a x24: ffff800021427580
x23: ffff8000214275c0 x22: ffff700004284eb0 x21: 0000000000000001
x20: 0000000000000001 x19: ffff0000d2ab88c0 x18: ffff800021427460
x17: ffff800018c59000 x16: ffff800008975ee4 x15: ffff800018739f80
x14: ffff0000ce25a638 x13: dfff800000000000 x12: 0000000000000001
x11: 1fffe0001a557118 x10: 0000000000000000 x9 : 0000000000000000
x8 : 0000000000000101 x7 : 0000000000000000 x6 : 0000000000000000
x5 : 0000000000000020 x4 : 0000000000000000 x3 : ffff80001240e414
x2 : 0000000000000000 x1 : 0000000000000004 x0 : 0000000000000001
Call trace:
__cmpwait_case_32 arch/arm64/include/asm/cmpxchg.h:252 [inline]
__cmpwait arch/arm64/include/asm/cmpxchg.h:278 [inline]
queued_spin_lock_slowpath+0x15c/0xe48 kernel/locking/qspinlock.c:383
queued_spin_lock include/asm-generic/qspinlock.h:114 [inline]
do_raw_spin_lock+0x330/0x358 kernel/locking/spinlock_debug.c:115
__raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
_raw_spin_lock+0x5c/0x6c kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
__netif_tx_lock include/linux/netdevice.h:4347 [inline]
netif_freeze_queues net/sched/sch_generic.c:459 [inline]
netif_tx_lock+0x9c/0x1d8 net/sched/sch_generic.c:468
netif_tx_lock_bh include/linux/netdevice.h:4431 [inline]
dev_watchdog_down net/sched/sch_generic.c:573 [inline]
dev_deactivate_many+0x274/0xa8c net/sched/sch_generic.c:1362
__dev_close_many+0x270/0x3c8 net/core/dev.c:1559
dev_close_many+0x1e0/0x46c net/core/dev.c:1597
dev_close+0x174/0x250 net/core/dev.c:1623
ser_release+0x188/0x238 drivers/net/caif/caif_serial.c:309
process_one_work+0x804/0x1484 kernel/workqueue.c:2292
worker_thread+0x8e4/0xfec kernel/workqueue.c:2439
kthread+0x250/0x2d8 kernel/kthread.c:376
ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:864


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.