INFO: task syz-executor:19216 blocked for more than 141 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:26760 pid:19216 tgid:19216 ppid:1      task_flags:0x40054c flags:0x00080003
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:5388 [inline]
 __schedule+0x1821/0x5740 kernel/sched/core.c:7189
 __schedule_loop kernel/sched/core.c:7268 [inline]
 schedule+0x164/0x360 kernel/sched/core.c:7283
 schedule_timeout+0xc3/0x2c0 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 kernel/sched/completion.c:132 [inline]
 wait_for_completion+0x2cc/0x5e0 kernel/sched/completion.c:153
 __flush_work+0xa17/0xc50 kernel/workqueue.c:4366
 __cancel_work_sync+0xbe/0x110 kernel/workqueue.c:4486
 hci_cmd_sync_clear+0x30/0x230 net/bluetooth/hci_sync.c:655
 hci_unregister_dev+0x194/0x5a0 net/bluetooth/hci_core.c:2712
 vhci_release+0x152/0x1a0 drivers/bluetooth/hci_vhci.c:690
 __fput+0x44f/0xa60 fs/file_table.c:510
 task_work_run+0x1d9/0x270 kernel/task_work.c:233
 exit_task_work include/linux/task_work.h:40 [inline]
 do_exit+0x70f/0x22c0 kernel/exit.c:976
 do_group_exit+0x21b/0x2d0 kernel/exit.c:1119
 get_signal+0x1284/0x1330 kernel/signal.c:3037
 arch_do_signal_or_restart+0xbc/0x840 arch/x86/kernel/signal.c:337
 __exit_to_user_mode_loop kernel/entry/common.c:64 [inline]
 exit_to_user_mode_loop+0xa9/0x680 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]
 syscall_exit_to_user_mode include/linux/entry-common.h:318 [inline]
 do_syscall_64+0x353/0xf80 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9a02d9caeb
RSP: 002b:00007ffe54ab8620 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffed RBX: 0000000000000005 RCX: 00007f9a02d9caeb
RDX: 00007ffe54ab8680 RSI: 0000000000008933 RDI: 0000000000000005
RBP: 00007ffe54ab87a0 R08: 0000000000000000 R09: 00007ffe54ab8778
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007f9a03b44620 R14: 0000000000000005 R15: 0000000000000000
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/31:
 #0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_lock_acquire include/linux/rcupdate.h:300 [inline]
 #0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: rcu_read_lock include/linux/rcupdate.h:838 [inline]
 #0: ffffffff8e95cca0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180 kernel/locking/lockdep.c:6775
2 locks held by getty/5385:
 #0: ffff8880377470a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70 drivers/tty/tty_ldisc.c:243
 #1: ffffc900032332e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0 drivers/tty/n_tty.c:2211
5 locks held by kworker/u9:2/5630:
5 locks held by kworker/u8:21/9806:
2 locks held by kworker/u8:22/9807:
5 locks held by kworker/u8:27/9813:
4 locks held by kworker/u9:4/18627:
4 locks held by kworker/u9:8/18990:
 #0: ffff88805807d140 ((wq_completion)hci5#16){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3289 [inline]
 #0: ffff88805807d140 ((wq_completion)hci5#16){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860 kernel/workqueue.c:3397
 #1: ffffc9000268fc40 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_one_work kernel/workqueue.c:3290 [inline]
 #1: ffffc9000268fc40 ((work_completion)(&hdev->rx_work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860 kernel/workqueue.c:3397
 #2: ffff8880756240b8 (&hdev->lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x9b/0x950 net/bluetooth/hci_event.c:3726
 #3: ffffffff8ff4af60 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_connect_cfm include/net/bluetooth/hci_core.h:2136 [inline]
 #3: ffffffff8ff4af60 (hci_cb_list_lock){+.+.}-{4:4}, at: hci_remote_features_evt+0x54c/0x950 net/bluetooth/hci_event.c:3760