INFO: task syz-executor:6696 blocked for more than 143 seconds.
      Not tainted syzkaller #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz-executor    state:D stack:0     pid:6696  tgid:6696  ppid:1      task_flags:0x40054c flags:0x00000019
Call trace:
 __switch_to+0x418/0x87c arch/arm64/kernel/process.c:742 (T)
 context_switch kernel/sched/core.c:5256 [inline]
 __schedule+0x1250/0x2a7c kernel/sched/core.c:6863
 __schedule_loop kernel/sched/core.c:6945 [inline]
 schedule+0xb4/0x230 kernel/sched/core.c:6960
 schedule_timeout+0xac/0x270 kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x288/0x3f8 kernel/sched/completion.c:100
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x44/0x5c kernel/sched/completion.c:153
 __flush_work+0x714/0x8c0 kernel/workqueue.c:4277
 __cancel_work_sync kernel/workqueue.c:4397 [inline]
 cancel_work_sync+0xc4/0x120 kernel/workqueue.c:4434
 hci_cmd_sync_clear+0x38/0x1e4 net/bluetooth/hci_sync.c:655
 hci_unregister_dev+0x180/0x52c net/bluetooth/hci_core.c:2711
 vhci_release+0x12c/0x17c drivers/bluetooth/hci_vhci.c:690
 __fput+0x340/0x75c fs/file_table.c:468
 ____fput+0x20/0x58 fs/file_table.c:496
 task_work_run+0x1dc/0x260 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x52c/0x1a1c kernel/exit.c:971
 do_group_exit+0x194/0x22c kernel/exit.c:1112
 get_signal+0x11dc/0x12f8 kernel/signal.c:3034
 arch_do_signal_or_restart+0x268/0x46d4 arch/arm64/kernel/signal.c:1619
 __exit_to_user_mode_loop kernel/entry/common.c:41 [inline]
 exit_to_user_mode_loop+0x88/0x18c kernel/entry/common.c:75
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline]
 exit_to_user_mode_prepare_legacy include/linux/irq-entry-common.h:242 [inline]
 arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:81 [inline]
 el0_svc+0x17c/0x26c arch/arm64/kernel/entry-common.c:725
 el0t_64_sync_handler+0x84/0x12c arch/arm64/kernel/entry-common.c:743
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:596

Showing all locks held in the system:
2 locks held by kworker/0:1/10:
1 lock held by khungtaskd/32:
 #0: ffff80008fa5b6e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x4/0x48 include/linux/rcupdate.h:330
2 locks held by pr/ttyAMA-1/43:
3 locks held by kworker/u9:1/6161:
 #0: ffff0000dcb25148 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x63c/0x1558 kernel/workqueue.c:3231
 #1: ffff8000a5757be0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x6d0/0x1558 kernel/workqueue.c:3231
 #2: ffff0000c7d8cec0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x184/0x38c net/bluetooth/hci_sync.c:331
2 locks held by getty/6349:
 #0: ffff0000daeb20a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff800099f1e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x34c/0xfc8 drivers/tty/n_tty.c:2211

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