INFO: task kworker/u8:0:12 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:kworker/u8:0    state:D
 stack:26232 pid:12    tgid:12    ppid:2      task_flags:0x4208060 flags:0x00080000
Workqueue: events_unbound fsnotify_mark_destroy_workfn
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5295 [inline]
 __schedule+0xeb1/0x41f0 kernel/sched/core.c:6907
 __schedule_loop kernel/sched/core.c:6989 [inline]
 schedule+0xdd/0x390 kernel/sched/core.c:7004
 schedule_timeout+0x1b2/0x280 kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common+0x2e7/0x4c0 kernel/sched/completion.c:121
 __synchronize_srcu+0x1c3/0x2a0 kernel/rcu/srcutree.c:1520
 fsnotify_mark_destroy_workfn+0x112/0x350 fs/notify/mark.c:1106
 process_one_work+0x9d7/0x1920 kernel/workqueue.c:3275
 process_scheduled_works kernel/workqueue.c:3358 [inline]
 worker_thread+0x5da/0xe40 kernel/workqueue.c:3439
 kthread+0x370/0x450 kernel/kthread.c:467
 ret_from_fork+0x6c3/0xcb0 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Showing all locks held in the system:
6 locks held by kworker/0:1/10:
2 locks held by kworker/u8:0/12:
 #0: 
ffff8881000ac148
 (
(wq_completion)events_unbound
){+.+.}-{0:0}
, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: 
ffffc900000cfd18
 (
(reaper_work).work){+.+.}-{0:0}
, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
3 locks held by kworker/1:1/28:
 #0: ffff88810006b548
 ((wq_completion)events
){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc900001e7d18 (free_ipc_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
 #2: 
ffffffff896ec1b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: exp_funnel_lock+0x19e/0x3c0 kernel/rcu/tree_exp.h:343
1 lock held by khungtaskd/30:
 #0: ffffffff896e05a0 (rcu_read_lock){....}-{1:3}
, at: rcu_lock_acquire include/linux/rcupdate.h:312 [inline]
, at: rcu_read_lock include/linux/rcupdate.h:850 [inline]
, at: debug_show_all_locks+0x3d/0x184 kernel/locking/lockdep.c:6775
2 locks held by kworker/u8:2/36:
 #0: ffff8881000ac948 ((wq_completion)events_unbound#2){+.+.}-{0:0}
, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: 
ffffc90000267d18 (
(work_completion)(&sub_info->work)
){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
4 locks held by kworker/u8:3/46:
 #0: ffff888101299148 ((wq_completion)netns){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc90000517d18
 (net_cleanup_work){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
 #2: 
ffffffff8aae0830 (pernet_ops_rwsem){++++}-{4:4}, at: cleanup_net+0xb8/0x9e0 net/core/net_namespace.c:675
 #3: ffffffff8aaf8e68 (rtnl_mutex){+.+.}-{4:4}, at: ops_exit_rtnl_list net/core/net_namespace.c:173 [inline]
 #3: ffffffff8aaf8e68 (rtnl_mutex){+.+.}-{4:4}, at: ops_undo_list+0x7ec/0xab0 net/core/net_namespace.c:248
2 locks held by kworker/u8:5/70:
 #0: ffff8881000ac948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: ffffc900005e7d18
 ((work_completion)(&sub_info->work)
){+.+.}-{0:0}
, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
3 locks held by udevd/2852:
2 locks held by getty/2915:
 #0: ffff888112d350a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x24/0x80 drivers/tty/tty_ldisc.c:243
 #1: ffffc900000432f0
 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x419/0x1500 drivers/tty/n_tty.c:2211
4 locks held by kworker/0:2/3003:
5 locks held by kworker/0:3/5778:
5 locks held by kworker/1:3/5784:
 #0: ffff888105684148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}
, at: process_one_work+0x1287/0x1920 kernel/workqueue.c:3250
 #1: 
ffffc9000216fd18 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_one_work+0x93c/0x1920 kernel/workqueue.c:3251
 #2: ffff88810bb3d198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #2: ffff88810bb3d198 (&dev->mutex){....}-{4:4}, at: hub_event+0x1bd/0x4af0 drivers/usb/core/hub.c:5899
 #3: ffff8881076ee198 (&dev->mutex){....}-{4:4}, at: device_lock include/linux/device.h:895 [inline]
 #3: ffff8881076ee198 (&dev->mutex){....}-{4:4}, at: usb_disconnect+0x10a/0x9a0 drivers/usb/core/hub.c:2336
 #4: ffffffff89e7b9a8 (dev_pm_qos_sysfs_mtx){+.+.}-{4:4}, at: dev_pm_qos_constraints_destroy+0x28/0x780 drivers/base/power/qos.c:254
4 locks held by udevd/5785:
 #0: ffff88812785a418 (&p->lock){+.+.}-{4:4}, at: seq_read_iter+0xe1/0x1270 fs/seq_file.c:183
 #1: 
ffff8881083b2088 (&of->mutex#2){+.+.}-{4:4}, at: kernfs_seq_start+0x4f/0x2a0 fs/kernfs/file.c:172