INFO: task syz-executor:4809 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:4809  tgid:4809  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:5387 [inline]
 __schedule+0x1b74/0x2d24 kernel/sched/core.c:7188
 __schedule_loop kernel/sched/core.c:7267 [inline]
 schedule+0xa4/0x140 kernel/sched/core.c:7282
 schedule_timeout+0xc0/0x294 kernel/time/sleep_timeout.c:75
 do_wait_for_common+0x208/0x380 kernel/sched/completion.c:100
 __wait_for_common kernel/sched/completion.c:121 [inline]
 wait_for_common+0x50/0x74 kernel/sched/completion.c:132
 wait_for_completion+0x18/0x24 kernel/sched/completion.c:153
 __flush_work+0x72c/0x8f0 kernel/workqueue.c:4354
 __cancel_work_sync+0xc8/0x144 kernel/workqueue.c:4474
 cancel_work_sync+0x24/0x38 kernel/workqueue.c:4511
 hci_cmd_sync_clear+0x30/0xcc net/bluetooth/hci_sync.c:655
 hci_unregister_dev+0x178/0x49c net/bluetooth/hci_core.c:2712
 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:975
 do_group_exit+0x194/0x22c kernel/exit.c:1117
 get_signal+0xfb0/0x1094 kernel/signal.c:3037
 arch_do_signal_or_restart+0x284/0x43bc 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]
 exit_to_user_mode_prepare_legacy include/linux/irq-entry-common.h:224 [inline]
 arm64_exit_to_user_mode arch/arm64/kernel/entry-common.c:86 [inline]
 el0_svc+0x180/0x25c arch/arm64/kernel/entry-common.c:724
 el0t_64_sync_handler+0x48/0x148 arch/arm64/kernel/entry-common.c:742
 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: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: __ll_sc_atomic64_fetch_or arch/arm64/include/asm/atomic_ll_sc.h:-1 [inline]
 #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: arch_atomic64_fetch_or arch/arm64/include/asm/atomic.h:86 [inline]
 #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: raw_atomic64_fetch_or include/linux/atomic/atomic-arch-fallback.h:3816 [inline]
 #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: raw_atomic_long_fetch_or include/linux/atomic/atomic-long.h:1090 [inline]
 #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: arch_test_and_set_bit include/asm-generic/bitops/atomic.h:42 [inline]
 #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: test_and_set_bit include/asm-generic/bitops/instrumented-atomic.h:72 [inline]
 #0: ffff800088ac66e0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire+0x0/0x44 kernel/sched/sched.h:3869
2 locks held by pr/ttyAMA-1/41:
2 locks held by getty/4449:
 #0: ffff0000d3e710a0 (&tty->ldisc_sem){++++}-{0:0}, at: ldsem_down_read+0x3c/0x4c drivers/tty/tty_ldsem.c:340
 #1: ffff80009228b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x354/0xf84 drivers/tty/n_tty.c:2211
3 locks held by kworker/u9:1/4767:
 #0: ffff0000daae6940 ((wq_completion)hci0){+.+.}-{0:0}, at: process_one_work+0x640/0x173c kernel/workqueue.c:3276
 #1: ffff80009af77be0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_one_work+0x6a4/0x173c kernel/workqueue.c:3276
 #2: ffff0000dd2d4ea0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x17c/0x37c net/bluetooth/hci_sync.c:331

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