INFO: task syz.0.1903:11361 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.1903      state:D stack:28232 pid:11361 tgid:11360 ppid:5815   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 bdev_open+0xe0/0xd30
 bdev_file_open_by_dev+0x1be/0x240
 setup_bdev_super+0x5a/0x5b0
 get_tree_bdev_flags+0x366/0x4d0
 vfs_get_tree+0x92/0x2b0
 do_new_mount+0x302/0xa10
 __se_sys_mount+0x313/0x410
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fd27518efc9
RSP: 002b:00007fd275f65038 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007fd2753e5fa0 RCX: 00007fd27518efc9
RDX: 0000200000000000 RSI: 0000200000000040 RDI: 0000200000000500
RBP: 00007fd275211f91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000008007 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fd2753e6038 R14: 00007fd2753e5fa0 R15: 00007ffcc2a59648
 </TASK>

Showing all locks held in the system:
2 locks held by kworker/0:0H/11:
1 lock held by khungtaskd/35:
 #0: ffffffff8df3d620 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by kworker/u9:3/1091:
 #0: ffff8881062fa948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90007d3fba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
2 locks held by getty/5641:
 #0: ffff8881767720a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by kworker/0:4/5851:
1 lock held by udevd/6258:
 #0: ffff888106b21358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
6 locks held by kworker/1:6/10541:
 #0: ffff88816805f148 ((wq_completion)usb_hub_wq){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90007737ba0 ((work_completion)(&hub->events)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
 #2: ffff88810a350198 (&dev->mutex){....}-{4:4}, at: hub_event+0x184/0x4a20
 #3: ffff88810a353518 (&port_dev->status_lock){+.+.}-{4:4}, at: hub_event+0x21b8/0x4a20
 #4: ffff888109c42168 (hcd->address0_mutex){+.+.}-{4:4}, at: hub_event+0x21e5/0x4a20
 #5: ffffffff8eb968d0 (ehci_cf_port_reset_rwsem){.+.+}-{4:4}, at: hub_port_reset+0x163/0x1750
2 locks held by syz.0.1903/11361:
 #0: ffff8881bfb7a0e0 (&type->s_umount_key#128/1){+.+.}-{4:4}, at: alloc_super+0x1bb/0x930
 #1: ffff888106b21358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
2 locks held by kworker/u10:32/13931:
 #0: ffff888100089948 ((wq_completion)events_unbound#2){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90003597ba0 ((reaper_work).work){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0
2 locks held by kworker/u10:54/13953:
 #0: ffff8881062fa948 ((wq_completion)iou_exit){+.+.}-{0:0}, at: process_scheduled_works+0x9b4/0x17b0
 #1: ffffc90008537ba0 ((work_completion)(&ctx->exit_work)){+.+.}-{0:0}, at: process_scheduled_works+0x9ef/0x17b0

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

NMI backtrace for cpu 1
CPU: 1 UID: 0 PID: 35 Comm: khungtaskd Not tainted syzkaller #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+0xf60/0xfa0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 11 Comm: kworker/0:0H Not tainted syzkaller #0 PREEMPT(full) 
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.2-debian-1.16.2-1 04/01/2014
Workqueue: events_highpri snd_vmidi_output_work
RIP: 0010:__sanitizer_cov_trace_pc+0x0/0x70
Code: 89 fb e8 23 00 00 00 48 8b 3d 04 ea d2 0b 48 89 de 5b e9 f3 a5 5a 00 cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 <f3> 0f 1e fa 48 8b 04 24 65 48 8b 0c 25 08 e0 6e 92 65 8b 15 08 c4
RSP: 0018:ffffc90000107398 EFLAGS: 00000086
RAX: ffffc90000107ff0 RBX: dffffc0000000000 RCX: ffff8881023b1d00
RDX: 0000000040000002 RSI: 0000000000000000 RDI: 0000000000000000
RBP: ffffc90000107570 R08: ffff8881023b1d07 R09: 1ffff110204763a0
R10: dffffc0000000000 R11: ffffed10204763a1 R12: 0000000000000000
R13: ffff888102abba00 R14: ffff8881023b1d00 R15: ffff888102abba20
FS:  0000000000000000(0000) GS:ffff88818eb32000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000200000009000 CR3: 000000010b964000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __switch_to+0xd90/0x1690
 __schedule+0x1798/0x4cc0
 preempt_schedule_common+0x83/0xd0
 preempt_schedule+0xae/0xc0
 preempt_schedule_thunk+0x16/0x30
 _raw_spin_unlock_irqrestore+0xfd/0x110
 snd_rawmidi_transmit+0xc9/0x100
 snd_vmidi_output_work+0x1a3/0x410
 process_scheduled_works+0xae1/0x17b0
 worker_thread+0x8a0/0xda0
 kthread+0x711/0x8a0
 ret_from_fork+0x4bc/0x870
 ret_from_fork_asm+0x1a/0x30
 </TASK>
