INFO: task syz-executor:5244 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:5244  tgid:5244  ppid:1      task_flags:0x40054c flags:0x00800019
Call trace:
 __switch_to+0x2b0/0x6e0 arch/arm64/kernel/process.c:810 (T)
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1bec/0x2dcc kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0x140/0x218 kernel/sched/core.c:7283
 schedule_timeout+0xc0/0x28c kernel/time/sleep_timeout.c:75
 do_wait_for_common kernel/sched/completion.c:100 [inline]
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common+0x204/0x380 kernel/sched/completion.c:132
 wait_for_completion+0x18/0x24 kernel/sched/completion.c:153
 __flush_work+0x814/0xa18 kernel/workqueue.c:4366
 __cancel_work_sync+0xc8/0x144 kernel/workqueue.c:4486
 cancel_work_sync+0x24/0x38 kernel/workqueue.c:4523
 hci_cmd_sync_clear+0x30/0xcc net/bluetooth/hci_sync.c:655
 hci_unregister_dev+0x178/0x49c net/bluetooth/hci_core.c:2675
 vhci_release+0x12c/0x17c drivers/bluetooth/hci_vhci.c:690
 __fput+0x340/0x744 fs/file_table.c:510
 ____fput+0x20/0x30 fs/file_table.c:538
 task_work_run+0x1c4/0x254 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x580/0x1a6c kernel/exit.c:976
 do_group_exit+0x194/0x22c kernel/exit.c:1119
 get_signal+0xfb0/0x1094 kernel/signal.c:3038
 arch_do_signal_or_restart+0x290/0x43a0 arch/arm64/kernel/signal.c:1665
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0x70/0x17c kernel/entry/common.c:98
 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline]
 syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline]
 arm64_syscall_exit_to_user_mode arch/arm64/kernel/entry-common.c:88 [inline]
 el0_svc+0x18c/0x260 arch/arm64/kernel/entry-common.c:737
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:755
 el0t_64_sync+0x198/0x19c arch/arm64/kernel/entry.S:594

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffff800088b67320 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffff800088b67320 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffff800088b67320 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x4c/0x188 kernel/locking/lockdep.c:6775
2 locks held by pr/ttyAMA-1/41:
3 locks held by kworker/0:2/1027:
 #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff0000c002b540 ((wq_completion)events){+.+.}-{0:0}, at: process_scheduled_works+0x748/0x1098 kernel/workqueue.c:3397
 #1: ffff800094477c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #1: ffff800094477c40 ((work_completion)(&data->fib_event_work)){+.+.}-{0:0}, at: process_scheduled_works+0x750/0x1098 kernel/workqueue.c:3397
 #2: ffff0000d0dab250 (&data->fib_lock){+.+.}-{4:4}, at: nsim_fib_event_work+0x18c/0x30c drivers/net/netdevsim/fib.c:1490
2 locks held by getty/4489:
 #0: ffff0000d45590a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009232e2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x354/0xf84 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:2/4749:
 #0: ffff0000d99fa140 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff0000d99fa140 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x748/0x1098 kernel/workqueue.c:3397
 #1: ffff80009adc7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #1: ffff80009adc7c40 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x750/0x1098 kernel/workqueue.c:3397
 #2: ffff0000cc9d8ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x17c/0x37c net/bluetooth/hci_sync.c:331

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