INFO: task syz-executor:4439 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:4439  ppid:1      flags:0x0000000d
Call trace:
 __switch_to+0x2f4/0x550 arch/arm64/kernel/process.c:555
 context_switch kernel/sched/core.c:5246 [inline]
 __schedule+0xdb4/0x1a6c kernel/sched/core.c:6563
 schedule+0xc4/0x170 kernel/sched/core.c:6639
 schedule_timeout+0xc8/0x2f4 kernel/time/timer.c:2144
 do_wait_for_common+0x28c/0x3ec kernel/sched/completion.c:85
 __wait_for_common kernel/sched/completion.c:106 [inline]
 wait_for_common kernel/sched/completion.c:117 [inline]
 wait_for_completion+0x44/0x5c kernel/sched/completion.c:138
 __flush_work+0x140/0x1ec kernel/workqueue.c:3076
 __cancel_work_timer+0x2f8/0x450 kernel/workqueue.c:3163
 cancel_work_sync+0x24/0x38 kernel/workqueue.c:3199
 hci_cmd_sync_clear+0x38/0x1e8 net/bluetooth/hci_sync.c:680
 hci_unregister_dev+0x184/0x4c8 net/bluetooth/hci_core.c:2714
 vhci_release+0x7c/0xcc drivers/bluetooth/hci_vhci.c:565
 __fput+0x1b4/0x7b0 fs/file_table.c:320
 ____fput+0x20/0x30 fs/file_table.c:348
 task_work_run+0x1f4/0x280 kernel/task_work.c:203
 exit_task_work include/linux/task_work.h:39 [inline]
 do_exit+0x54c/0x19ac kernel/exit.c:887
 do_group_exit+0x198/0x238 kernel/exit.c:1030
 get_signal+0x11f4/0x133c kernel/signal.c:2884
 do_signal arch/arm64/kernel/signal.c:1095 [inline]
 do_notify_resume+0x364/0x2c84 arch/arm64/kernel/signal.c:1148
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_svc+0x98/0x128 arch/arm64/kernel/entry-common.c:638
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Showing all locks held in the system:
1 lock held by rcu_tasks_kthre/12:
 #0: ffff800015597db0 (rcu_tasks.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517
1 lock held by rcu_tasks_trace/13:
 #0: ffff8000155985d0 (rcu_tasks_trace.tasks_gp_mutex){+.+.}-{3:3}, at: rcu_tasks_one_gp+0x40/0xc48 kernel/rcu/tasks.h:517
1 lock held by khungtaskd/28:
 #0: ffff800015597440 (rcu_read_lock){....}-{1:2}, at: rcu_lock_acquire+0xc/0x44 include/linux/rcupdate.h:349
2 locks held by getty/4082:
 #0: ffff0000d11a4098 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800020aab2f0 (&ldata->atomic_read_lock){+.+.}-{3:3}, at: n_tty_read+0x2e8/0xfa8 drivers/tty/n_tty.c:2198
3 locks held by kworker/u5:1/4366:
 #0: ffff0000de9db938 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x69c/0x13bc kernel/workqueue.c:-1
 #1: ffff800021107c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x6e8/0x13bc kernel/workqueue.c:2267
 #2: ffff0000cc9b11e0 (&hdev->req_lock){+.+.}-{3:3}, at: hci_cmd_sync_work+0x180/0x32c net/bluetooth/hci_sync.c:327
3 locks held by syz.0.8265/12956:

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