INFO: task kworker/u4:9:21844 blocked for more than 143 seconds.
      Not tainted 6.8.0-rc2-next-20240202-syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u4:9    state:D stack:22744 pid:21844 tgid:21844 ppid:2      flags:0x00004000
Workqueue: netns cleanup_net
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5400 [inline]
 __schedule+0x17df/0x4a40 kernel/sched/core.c:6727
 __schedule_loop kernel/sched/core.c:6804 [inline]
 schedule+0x14b/0x320 kernel/sched/core.c:6819
 schedule_timeout+0xb0/0x310 kernel/time/timer.c:2159
 do_wait_for_common kernel/sched/completion.c:95 [inline]
 __wait_for_common kernel/sched/completion.c:116 [inline]
 wait_for_common kernel/sched/completion.c:127 [inline]
 wait_for_completion+0x355/0x620 kernel/sched/completion.c:148
 __flush_workqueue+0x730/0x1630 kernel/workqueue.c:3617
 drain_workqueue+0xc9/0x390 kernel/workqueue.c:3730
 destroy_workqueue+0xba/0xc40 kernel/workqueue.c:5319
 bond_destructor+0x4d/0x80 drivers/net/bonding/bond_main.c:5846
 netdev_run_todo+0xd4f/0xf40 net/core/dev.c:10581
 default_device_exit_batch+0x975/0x9f0 net/core/dev.c:11625
 ops_exit_list net/core/net_namespace.c:175 [inline]
 cleanup_net+0x775/0xb90 net/core/net_namespace.c:618
 process_one_work kernel/workqueue.c:3049 [inline]
 process_scheduled_works+0x913/0x14f0 kernel/workqueue.c:3125
 worker_thread+0xa60/0x1000 kernel/workqueue.c:3206
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242
 </TASK>

Showing all locks held in the system:
1 lock held by ksoftirqd/1/23:
1 lock held by khungtaskd/29:
 #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: rcu_read_lock include/linux/rcupdate.h:750 [inline]
 #0: ffffffff8e130d60 (rcu_read_lock){....}-{1:2}, at: debug_show_all_locks+0x55/0x2a0 kernel/locking/lockdep.c:6614
2 locks held by kworker/u4:2/34:
2 locks held by getty/4825:
 #0: ffff88802c5180a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900031332f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x6b5/0x1e10 drivers/tty/n_tty.c:2201
1 lock held by syz-executor.1/5099:
 #0: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:323 [inline]
 #0: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x463/0x820 kernel/rcu/tree_exp.h:939
3 locks held by kworker/0:5/5219:
 #0: ffff888014c7cd48 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline]
 #0: ffff888014c7cd48 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125
 #1: ffffc90004867d20 (free_ipc_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline]
 #1: ffffc90004867d20 (free_ipc_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125
 #2: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: exp_funnel_lock kernel/rcu/tree_exp.h:291 [inline]
 #2: ffffffff8e1360f8 (rcu_state.exp_mutex){+.+.}-{3:3}, at: synchronize_rcu_expedited+0x39a/0x820 kernel/rcu/tree_exp.h:939
3 locks held by kworker/u4:9/21844:
 #0: ffff888015acd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline]
 #0: ffff888015acd948 ((wq_completion)netns){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125
 #1: ffffc90014e3fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3024 [inline]
 #1: ffffc90014e3fd20 (net_cleanup_work){+.+.}-{0:0}, at: process_scheduled_works+0x825/0x14f0 kernel/workqueue.c:3125
 #2: ffffffff8f36da50 (pernet_ops_rwsem){++++}-{3:3}, at: cleanup_net+0xf5/0xb90 net/core/net_namespace.c:580
6 locks held by syz-executor.2/30942:

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

NMI backtrace for cpu 1
CPU: 1 PID: 29 Comm: khungtaskd Not tainted 6.8.0-rc2-next-20240202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x1e7/0x2e0 lib/dump_stack.c:106
 nmi_cpu_backtrace+0x49c/0x4d0 lib/nmi_backtrace.c:113
 nmi_trigger_cpumask_backtrace+0x198/0x320 lib/nmi_backtrace.c:62
 trigger_all_cpu_backtrace include/linux/nmi.h:160 [inline]
 check_hung_uninterruptible_tasks kernel/hung_task.c:222 [inline]
 watchdog+0xfb0/0xff0 kernel/hung_task.c:379
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:242
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 5107 Comm: syz-executor.3 Not tainted 6.8.0-rc2-next-20240202-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/25/2024
RIP: 0010:kasan_check_range+0x1b8/0x290 mm/kasan/generic.c:189
Code: 4d 01 fb 48 8d 5d 07 48 85 ed 48 0f 49 dd 48 83 e3 f8 48 29 dd 74 12 41 80 3b 00 0f 85 a6 00 00 00 49 ff c3 48 ff cd 75 ee 5b <41> 5c 41 5e 41 5f 5d c3 cc cc cc cc 40 84 ed 75 5f f7 c5 00 ff 00
RSP: 0018:ffffc9000397f468 EFLAGS: 00000056
RAX: 0000000000000001 RBX: 0000000000000021 RCX: ffffffff81717b6b
RDX: 0000000000000000 RSI: 0000000000000008 RDI: ffffffff92ca3420
RBP: 0000000000000000 R08: ffffffff92ca3427 R09: 1ffffffff2594684
R10: dffffc0000000000 R11: fffffbfff2594685 R12: 0000000000000000
R13: 0000000000000021 R14: dffffc0000000001 R15: fffffbfff2594685
FS:  00005555564fb480(0000) GS:ffff8880b9400000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f1530d7a538 CR3: 000000003887c000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <NMI>
 </NMI>
 <TASK>
 instrument_atomic_read include/linux/instrumented.h:68 [inline]
 _test_bit include/asm-generic/bitops/instrumented-non-atomic.h:141 [inline]
 hlock_class kernel/locking/lockdep.c:228 [inline]
 check_wait_context kernel/locking/lockdep.c:4773 [inline]
 __lock_acquire+0x4bb/0x1fd0 kernel/locking/lockdep.c:5087
 lock_acquire+0x1e4/0x530 kernel/locking/lockdep.c:5754
 rcu_lock_acquire include/linux/rcupdate.h:298 [inline]
 rcu_read_lock include/linux/rcupdate.h:750 [inline]
 net_generic+0x3c/0x240 include/net/netns/generic.h:45
 xt_find_table_lock+0x2e/0x3b0 net/netfilter/x_tables.c:1237
 xt_request_find_table_lock+0x26/0x100 net/netfilter/x_tables.c:1284
 get_info net/ipv6/netfilter/ip6_tables.c:979 [inline]
 do_ip6t_get_ctl+0x89e/0x1820 net/ipv6/netfilter/ip6_tables.c:1660
 nf_getsockopt+0x299/0x2c0 net/netfilter/nf_sockopt.c:116
 ipv6_getsockopt+0x263/0x380 net/ipv6/ipv6_sockglue.c:1488
 tcp_getsockopt+0x163/0x1c0 net/ipv4/tcp.c:4372
 do_sock_getsockopt+0x373/0x850 net/socket.c:2373
 __sys_getsockopt+0x271/0x330 net/socket.c:2402
 __do_sys_getsockopt net/socket.c:2412 [inline]
 __se_sys_getsockopt net/socket.c:2409 [inline]
 __x64_sys_getsockopt+0xb5/0xd0 net/socket.c:2409
 do_syscall_64+0xfb/0x240
 entry_SYSCALL_64_after_hwframe+0x6d/0x75
RIP: 0033:0x7f1530c7f94a
Code: c4 c1 e0 1a 0d 00 00 04 00 89 01 e9 e0 fe ff ff e8 3b 05 00 00 66 2e 0f 1f 84 00 00 00 00 00 90 49 89 ca b8 37 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 06 c3 0f 1f 44 00 00 48 c7 c2 b0 ff ff ff f7
RSP: 002b:00007ffe09fc61e8 EFLAGS: 00000242 ORIG_RAX: 0000000000000037
RAX: ffffffffffffffda RBX: 00007ffe09fc6210 RCX: 00007f1530c7f94a
RDX: 0000000000000040 RSI: 0000000000000029 RDI: 0000000000000003
RBP: 0000000000000003 R08: 00007ffe09fc620c R09: 0079746972756365
R10: 00007ffe09fc6210 R11: 0000000000000242 R12: 00007f1530d7b200
R13: 00007ffe09fc620c R14: 0000000000000000 R15: 00007f1530d7cd00
 </TASK>