INFO: task syz.0.905:12362 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.905       state:D stack:28280 pid:12362 tgid:12361 ppid:5855   task_flags:0x400040 flags:0x00004004
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 __mutex_lock+0x7e6/0x1350
 bdev_open+0xe0/0xd30
 blkdev_open+0x457/0x600
 do_dentry_open+0x953/0x13f0
 vfs_open+0x3b/0x340
 path_openat+0x2ee5/0x3830
 do_filp_open+0x1fa/0x410
 do_sys_openat2+0x121/0x1c0
 __x64_sys_openat+0x138/0x170
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f504ef8d550
RSP: 002b:00007f504fea1b70 EFLAGS: 00000293 ORIG_RAX: 0000000000000101
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f504ef8d550
RDX: 0000000000000000 RSI: 00007f504fea1c10 RDI: 00000000ffffff9c
RBP: 00007f504fea1c10 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000293 R12: cccccccccccccccd
R13: 00007f504f1c6038 R14: 00007f504f1c5fa0 R15: 00007ffc7f291a28
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e33cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by udevd/5295:
2 locks held by getty/5676:
 #0: ffff888024ded0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000291b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
1 lock held by udevd/5915:
 #0: ffff888021666358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
1 lock held by syz.0.905/12362:
 #0: ffff888021666358 (&disk->open_mutex){+.+.}-{4:4}, at: bdev_open+0xe0/0xd30
2 locks held by syz.1.1613/19600:

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

NMI backtrace for cpu 0
CPU: 0 UID: 0 PID: 34 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+0x47f/0x820
 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: 0 Comm: swapper/1 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
RIP: 0010:_raw_spin_unlock_irqrestore+0x85/0x110
Code: 00 fc ff df 4b 89 04 27 48 83 c7 18 48 8b 75 08 e8 f0 47 1d f6 4c 89 f7 e8 48 df 1d f6 f7 c3 00 02 00 00 74 05 e8 0b 40 47 f6 <48> c7 44 24 20 00 00 00 00 9c 8f 44 24 20 f6 44 24 21 02 75 4f f7
RSP: 0018:ffffc900001e0c00 EFLAGS: 00000046
RAX: 1ffffffff1c35263 RBX: 0000000000000802 RCX: 0000000000000001
RDX: 0000000000000000 RSI: 0000000000000004 RDI: ffff88802515e050
RBP: ffffc900001e0c98 R08: ffff88802515e053 R09: 1ffff11004a2bc0a
R10: dffffc0000000000 R11: ffffed1004a2bc0b R12: dffffc0000000000
R13: 1ffff11026cc75be R14: ffff88802515e050 R15: 1ffff9200003c180
FS:  0000000000000000(0000) GS:ffff8881a39fa000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffeb6977ff8 CR3: 0000000022d36000 CR4: 00000000000006f0
Call Trace:
 <IRQ>
 try_to_wake_up+0x7b7/0x12b0
 hrtimer_wakeup+0x4e/0x60
 __hrtimer_run_queues+0x52c/0xc60
 hrtimer_interrupt+0x45b/0xaa0
 __sysvec_apic_timer_interrupt+0x10b/0x410
 sysvec_apic_timer_interrupt+0xa1/0xc0
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x1a/0x20
RIP: 0010:pv_native_safe_halt+0x13/0x20
Code: cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 f3 0f 1e fa eb 07 0f 00 2d 33 91 29 00 f3 0f 1e fa fb f4 <e9> 08 e7 02 00 cc cc cc cc cc cc cc cc 90 90 90 90 90 90 90 90 90
RSP: 0018:ffffc90000177de0 EFLAGS: 00000286
RAX: e2a8c83f0c47ea00 RBX: ffffffff81979518 RCX: e2a8c83f0c47ea00
RDX: 0000000000000001 RSI: ffffffff8dbbc9d5 RDI: ffffffff8c037100
RBP: ffffc90000177f10 R08: ffff888136632f9b R09: 1ffff11026cc65f3
R10: dffffc0000000000 R11: ffffed1026cc65f4 R12: ffffffff8fc3eb30
R13: 0000000000000001 R14: 0000000000000001 R15: 1ffff110200d2000
 default_idle+0x13/0x20
 default_idle_call+0x74/0xb0
 do_idle+0x1e8/0x510
 cpu_startup_entry+0x44/0x60
 start_secondary+0x101/0x110
 common_startup_64+0x13e/0x147
 </TASK>
