INFO: task syz.0.107:7360 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.107       state:D stack:24648 pid:7360  tgid:7359  ppid:7133   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1798/0x4cc0
 schedule+0x165/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x5fd/0x8f0
 down_read+0x98/0x2e0
 super_lock+0x2a9/0x3b0
 __iterate_supers+0x126/0x290
 __se_sys_quotactl+0x353/0x950
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9b0d98ec29
RSP: 002b:00007f9b0e747038 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f9b0dbd5fa0 RCX: 00007f9b0d98ec29
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000101
RBP: 00007f9b0da11e41 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f9b0dbd6038 R14: 00007f9b0dbd5fa0 R15: 00007ffeb5081a08
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e33d2e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5674:
 #0: ffff888022e010a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900028fe2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x43e/0x1400
2 locks held by syz-executor/6252:
2 locks held by syz-executor/6700:
4 locks held by syz-executor/7232:
1 lock held by syz.0.107/7360:
 #0: ffff888037a8e0e0 (&type->s_umount_key#56){++++}-{4:4}, at: super_lock+0x2a9/0x3b0
1 lock held by syz.7.316/9385:
1 lock held by syz.9.319/9392:

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

NMI backtrace for cpu 1
CPU: 1 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+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: 9392 Comm: syz.9.319 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:io_serial_in+0x77/0xc0
Code: e8 de f4 6a fc 44 89 f9 d3 e3 49 83 c6 40 4c 89 f0 48 c1 e8 03 42 80 3c 20 00 74 08 4c 89 f7 e8 8f 0a d0 fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 0a 48 2b 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90004636f58 EFLAGS: 00000006
RAX: 1ffffffff3400205 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 0000000000038cb4 RDI: 0000000000038cb5
RBP: ffffc90004637130 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff85555c10 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff9a001520 R15: 0000000000000000
FS:  00007f27da5d16c0(0000) GS:ffff8880b840a000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00005555897ee808 CR3: 0000000037d8c000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 serial8250_console_write+0x584/0x1ba0
 console_flush_all+0x6f3/0xb10
 console_unlock+0xbb/0x190
 vprintk_emit+0x4c5/0x590
 _printk+0xcf/0x120
 bch2_print_string_as_lines+0x135/0x250
 print_mount_opts+0x647/0x7a0
 bch2_fs_start+0x9e/0xda0
 bch2_fs_get_tree+0xb39/0x1520
 vfs_get_tree+0x92/0x2b0
 do_new_mount+0x302/0x9e0
 __se_sys_mount+0x313/0x410
 do_syscall_64+0xfa/0xfa0
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f27d97903ca
Code: d8 64 89 02 48 c7 c0 ff ff ff ff eb a6 e8 de 1a 00 00 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 49 89 ca b8 a5 00 00 00 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 a8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f27da5d0e68 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f27da5d0ef0 RCX: 00007f27d97903ca
RDX: 00002000000000c0 RSI: 00002000000003c0 RDI: 00007f27da5d0eb0
RBP: 00002000000000c0 R08: 00007f27da5d0ef0 R09: 0000000000000810
R10: 0000000000000810 R11: 0000000000000246 R12: 00002000000003c0
R13: 00007f27da5d0eb0 R14: 0000000000005aa3 R15: 0000200000000040
 </TASK>
