INFO: task syz.4.614:8477 blocked for more than 143 seconds.
      Not tainted 6.17.0-rc1-syzkaller-00036-gdfc0f6373094 #0
      Blocked by coredump.
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.4.614       state:D stack:25752 pid:8477  tgid:8477  ppid:7341   task_flags:0x40044c flags:0x00004006
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_timeout+0x9a/0x270
 wait_for_completion+0x2bf/0x5d0
 __flush_work+0x9b9/0xbc0
 __cancel_work_sync+0xbe/0x110
 hci_cmd_sync_clear+0x30/0x230
 hci_unregister_dev+0x194/0x510
 vhci_release+0x80/0xd0
 __fput+0x44c/0xa70
 task_work_run+0x1d4/0x260
 do_exit+0x6b5/0x2300
 do_group_exit+0x21c/0x2d0
 get_signal+0x1286/0x1340
 arch_do_signal_or_restart+0x9a/0x750
 exit_to_user_mode_loop+0x75/0x110
 do_syscall_64+0x2bd/0x3b0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f35965c14a5
RSP: 002b:00007f3597334f80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6
RAX: fffffffffffffdfc RBX: 00007f35967b5fa0 RCX: 00007f35965c14a5
RDX: 00007f3597334fc0 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f3596611e19 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000
R13: 00007f35967b6038 R14: 00007f35967b5fa0 R15: 00007fffe3c059b8
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/0:0/9:
 #0: ffff88801b7b9948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900000c7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff888023657198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff888036c48198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #4: ffff88801fb71160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
1 lock held by khungtaskd/35:
 #0: ffffffff8e139ee0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5671:
 #0: ffff8880268500a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900029062f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
5 locks held by kworker/1:4/5904:
 #0: ffff88801b7b9948 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc900041d7bc0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88802360f198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff888109314198 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
 #4: ffff88811c4dd160 (&dev->mutex){....}-{4:4}, at: __device_attach+0x88/0x400
3 locks held by kworker/u11:3/5992:
 #0: ffff88801c759948 ((wq_completion)hci0){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc9000446fbc0 ((work_completion)(&hdev->cmd_sync_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88801ff88dc0 (&hdev->req_lock){+.+.}-{4:4}, at: hci_cmd_sync_work+0x1d4/0x3a0
2 locks held by syz.2.860/9814:

=============================================

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 35 Comm: khungtaskd Not tainted 6.17.0-rc1-syzkaller-00036-gdfc0f6373094 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250
 nmi_cpu_backtrace+0x39e/0x3d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 watchdog+0xf93/0xfe0
 kthread+0x711/0x8a0
 ret_from_fork+0x3fc/0x770
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 0 to CPUs 1:
NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 9814 Comm: syz.2.860 Not tainted 6.17.0-rc1-syzkaller-00036-gdfc0f6373094 #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
RIP: 0033:0x7f93d1250c43
Code: 10 48 39 f0 72 6e 48 63 cd 48 01 c1 49 39 4f 08 72 4c 8d 4d ff 85 ed 74 33 66 0f 1f 44 00 00 48 39 f0 72 1b 4d 8b 07 49 89 c1 <49> 29 f1 47 0f b6 0c 08 45 84 c9 74 08 45 88 0c 00 49 8b 47 10 48
RSP: 002b:00007f93d22d24a0 EFLAGS: 00000206
RAX: 00000000008a5207 RBX: 00007f93d22d2540 RCX: 00000000000000e2
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 00007f93d22d25e0
RBP: 0000000000000102 R08: 00007f93c7000000 R09: 00000000008a5207
R10: 0000000000000000 R11: 00007f93d22d2550 R12: 0000000000000001
R13: 00007f93d142d980 R14: 0000000000000000 R15: 00007f93d22d25e0
FS:  00007f93d22d36c0 GS:  0000000000000000
