INFO: task kworker/u4:32:12655 blocked for more than 143 seconds.
      Not tainted 6.1.0-syzkaller-13822-g6feb57c2fd7c #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:32   state:D stack:26416 pid:12655 ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5244 [inline]
 __schedule+0xb8a/0x5450 kernel/sched/core.c:6555
 schedule+0xde/0x1b0 kernel/sched/core.c:6631
 rxrpc_destroy_all_calls+0x1ee/0x640 net/rxrpc/call_object.c:733
 rxrpc_exit_net+0x15c/0x300 net/rxrpc/net_ns.c:125
 ops_exit_list+0xb0/0x170 net/core/net_namespace.c:169
 cleanup_net+0x4ee/0xb10 net/core/net_namespace.c:606
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x669/0x1090 kernel/workqueue.c:2436
 kthread+0x2e8/0x3a0 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/11:
 #0: ffffffff8c78dcb0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by rcu_tasks_trace/12:
 #0: ffffffff8c78d9b0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x26/0xc70 kernel/rcu/tasks.h:507
1 lock held by khungtaskd/27:
 #0: ffffffff8c78e800 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x57/0x264 kernel/locking/lockdep.c:6494
2 locks held by klogd/4410:
 #0: ffff8880b993b5d8 (&rq->__lock){-.-.}-{2:2}, at: raw_spin_rq_lock_nested+0x2f/0x120 kernel/sched/core.c:537
 #1: ffffffff8c8f0600 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: update_rq_clock_task kernel/sched/core.c:704 [inline]
 #1: ffffffff8c8f0600 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: update_rq_clock kernel/sched/core.c:747 [inline]
 #1: ffffffff8c8f0600 (mmu_notifier_invalidate_range_start){+.+.}-{0:0}, at: update_rq_clock+0x241/0xaa0 kernel/sched/core.c:728
2 locks held by getty/4737:
 #0: ffff88814b58c098 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x26/0x80 drivers/tty/tty_ldisc.c:244
 #1: ffffc900020482f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0xef4/0x13e0 drivers/tty/n_tty.c:2177
5 locks held by kworker/u4:31/12651:
3 locks held by kworker/u4:32/12655:
 #0: ffff888012776138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic64_set arch/x86/include/asm/atomic64_64.h:34 [inline]
 #0: ffff888012776138 ((wq_completion)netns){+.+.}-{0:0}, at: arch_atomic_long_set include/linux/atomic/atomic-long.h:41 [inline]
 #0: ffff888012776138 ((wq_completion)netns){+.+.}-{0:0}, at: atomic_long_set include/linux/atomic/atomic-instrumented.h:1280 [inline]
 #0: ffff888012776138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_data kernel/workqueue.c:636 [inline]
 #0: ffff888012776138 ((wq_completion)netns){+.+.}-{0:0}, at: set_work_pool_and_clear_pending kernel/workqueue.c:663 [inline]
 #0: ffff888012776138 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x86d/0x1710 kernel/workqueue.c:2260
 #1: ffffc900061efda8 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x8a1/0x1710 kernel/workqueue.c:2264
 #2: ffffffff8e0a0d10 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0x9f/0xb10 net/core/net_namespace.c:568

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

NMI backtrace for cpu 0
CPU: 0 PID: 27 Comm: khungtaskd Not tainted 6.1.0-syzkaller-13822-g6feb57c2fd7c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x24/0x18a lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x333/0x3c0 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+0xc75/0xfc0 kernel/hung_task.c:377
 kthread+0x2e8/0x3a0 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: 20154 Comm: kworker/u4:0 Not tainted 6.1.0-syzkaller-13822-g6feb57c2fd7c #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022
Workqueue: bat_events batadv_nc_worker
RIP: 0010:lockdep_recursion_finish kernel/locking/lockdep.c:466 [inline]
RIP: 0010:lock_release+0x3ee/0x810 kernel/locking/lockdep.c:5690
Code: 74 0c 3c 03 7f 08 4c 89 f7 e8 2e 90 6a 00 45 89 e8 44 2b 44 24 40 45 39 87 30 0a 00 00 0f 85 9e 02 00 00 48 c7 c7 00 3f 4c 8a <e8> 6d 01 a2 08 b8 ff ff ff ff 65 0f c1 05 68 75 9f 7e 83 f8 01 0f
RSP: 0018:ffffc90005b47b40 EFLAGS: 00000046
RAX: 0000000000000002 RBX: 14db22b55b7e824f RCX: ffffc90005b47b90
RDX: 1ffff11006c35d8d RSI: 0000000000000000 RDI: ffffffff8a4c3f00
RBP: 1ffff92000b68f6a R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000002
R13: 0000000000000003 R14: ffff8880361aec70 R15: ffff8880361ae240
FS:  0000000000000000(0000) GS:ffff8880b9900000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f2d5bed5720 CR3: 000000007dd5c000 CR4: 00000000003506e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __raw_spin_unlock_bh include/linux/spinlock_api_smp.h:165 [inline]
 _raw_spin_unlock_bh+0x16/0x30 kernel/locking/spinlock.c:210
 spin_unlock_bh include/linux/spinlock.h:395 [inline]
 batadv_nc_purge_paths+0x2a5/0x3a0 net/batman-adv/network-coding.c:471
 batadv_nc_worker+0x8fd/0xfa0 net/batman-adv/network-coding.c:720
 process_one_work+0x9bf/0x1710 kernel/workqueue.c:2289
 worker_thread+0x669/0x1090 kernel/workqueue.c:2436
 kthread+0x2e8/0x3a0 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:308
 </TASK>