INFO: task syz.0.682:11911 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.682       state:D stack:25304 pid:11911 tgid:11910 ppid:11279  task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x14ef/0x4fb0
 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+0x516/0x990
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6cf4f9acb9
RSP: 002b:00007f6cf5ee9028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007f6cf5215fa0 RCX: 00007f6cf4f9acb9
RDX: 0000000000000000 RSI: 00002000000001c0 RDI: ffffffff80000401
RBP: 00007f6cf5008bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6cf5216038 R14: 00007f6cf5215fa0 R15: 00007ffce8bfafd8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e341b60 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5660:
 #0: ffff88811485c0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356b2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
4 locks held by syz-executor/8719:
1 lock held by syz.0.682/11911:
 #0: 
ffff888112f440e0 (&type->s_umount_key#84){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.746/12474:
 #0: ffff888112f440e0 (&type->s_umount_key#84){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.1.794/12907:
 #0: ffff888112f440e0 (&type->s_umount_key#84){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.7.965/14956:
 #0: ffff888112f440e0 (&type->s_umount_key#84){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz-executor/15361:
 #0: ffff888111ff20e0 (&type->s_umount_key#52){+.+.}-{4:4}, at: deactivate_super+0xa9/0xe0
 #1: ffffffff8e3476b8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x2d0/0x770
2 locks held by syz.9.1082/15887:
4 locks held by syz.9.1082/15905:
3 locks held by syz.3.1083/15891:

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

NMI backtrace for cpu 0
CPU: 0 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+0xe8/0x150
 nmi_cpu_backtrace+0x274/0x2d0
 nmi_trigger_cpumask_backtrace+0x17a/0x300
 sys_info+0x135/0x170
 watchdog+0xf90/0xfe0
 kthread+0x726/0x8b0
 ret_from_fork+0x51b/0xa40
 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: 15887 Comm: syz.9.1082 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 5e ae 9c 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 ad 03 fd 41 03 1e 89 da ec <0f> b6 c0 5b 41 5c 41 5e 41 5f e9 9a 9a 52 06 cc 44 89 f9 80 e1 07
RSP: 0018:ffffc900040b6718 EFLAGS: 00000006
RAX: 1ffffffff3403c05 RBX: 00000000000003f9 RCX: 0000000000000000
RDX: 00000000000003f9 RSI: 000000000007ffff RDI: 0000000000080000
RBP: ffffc900040b68b0 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: ffffffff8525d800 R12: dffffc0000000000
R13: dffffc0000000000 R14: ffffffff9a01e2c0 R15: 0000000000000000
FS:  00007fbe383b96c0(0000) GS:ffff8882a9a0b000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fbe2e1ff000 CR3: 00000001737c2000 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
 submit_bio_noacct+0x1179/0x1b50
 __submit_merged_bio+0x256/0x650
 __submit_merged_write_cond+0x269/0x530
 f2fs_write_data_pages+0x2806/0x3360
 do_writepages+0x32e/0x550
 filemap_write_and_wait_range+0x335/0x3f0
 f2fs_file_write_iter+0x857/0x2500
 iter_file_splice_write+0x99b/0x1100
 direct_splice_actor+0x101/0x160
 splice_direct_to_actor+0x53a/0xc70
 do_splice_direct+0x195/0x290
 do_sendfile+0x535/0x7c0
 __se_sys_sendfile64+0x144/0x1a0
 do_syscall_64+0xe2/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fbe3759acb9
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fbe383b9028 EFLAGS: 00000246 ORIG_RAX: 0000000000000028
RAX: ffffffffffffffda RBX: 00007fbe37815fa0 RCX: 00007fbe3759acb9
RDX: 0000000000000000 RSI: 0000000000000007 RDI: 0000000000000006
RBP: 00007fbe37608bf7 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000020fffe82 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fbe37816038 R14: 00007fbe37815fa0 R15: 00007fff73ca4ac8
 </TASK>
