INFO: task syz.7.2676:18537 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.2676      state:D stack:24608 pid:18537 tgid:18536 ppid:18190  task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1585/0x5340
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 user_get_super+0xc8/0x120
 __se_sys_quotactl+0x540/0x9e0
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fb83ad9c799
RSP: 002b:00007fb83bc25028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fb83b015fa0 RCX: 00007fb83ad9c799
RDX: 0000000000000000 RSI: 00002000000003c0 RDI: ffffffff80000800
RBP: 00007fb83ae32bd9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000200000000280 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fb83b016038 R14: 00007fb83b015fa0 R15: 00007fff96edbf58
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e7602e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5637:
 #0: ffff8881111c40a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900033d02f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
2 locks held by syz-executor/9991:
1 lock held by syz.7.2676/18537:
 #0: ffff888114ef80e0 (&type->s_umount_key#58){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
3 locks held by syz.1.3596/23026:

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

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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 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: 23026 Comm: syz.1.3596 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 0e 4a 85 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 3f 6f ef fc 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f c3 cc cc cc cc cc 44 89 f9 80 e1 07
RSP: 0018:ffffc90003b26a78 EFLAGS: 00000006
RAX: 1ffffffff34b9505 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc90003b26c10 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff85404120 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff9a5ca960 R15: 0000000000000000
FS:  00007faf882306c0(0000) GS:ffff8882a9464000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffc68e76c40 CR3: 000000011c3c8000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 serial8250_console_write+0x540/0x1ba0
 console_flush_all+0x718/0xb20
 console_unlock+0xd1/0x1c0
 vprintk_emit+0x485/0x560
 _printk+0xdd/0x130
 set_capacity_and_notify+0x2c5/0x320
 loop_set_size+0x44/0xb0
 loop_configure+0x9ac/0xdf0
 lo_ioctl+0x447/0x1fb0
 blkdev_ioctl+0x5e3/0x740
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7faf8739c42b
Code: 00 48 89 44 24 18 31 c0 48 8d 44 24 60 c7 04 24 10 00 00 00 48 89 44 24 08 48 8d 44 24 20 48 89 44 24 10 b8 10 00 00 00 0f 05 <89> c2 3d 00 f0 ff ff 77 1c 48 8b 44 24 18 64 48 2b 04 25 28 00 00
RSP: 002b:00007faf8822fdb0 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 0000000000000004 RCX: 00007faf8739c42b
RDX: 0000000000000003 RSI: 0000000000004c00 RDI: 0000000000000004
RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000003
R13: 00007faf8822fee0 R14: 00007faf8822fea0 R15: 00007faf7d000000
 </TASK>
