INFO: task syz.7.207:7505 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.7.207       state:D stack:25432 pid:7505  tgid:7504  ppid:6827   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f102959cdd9
RSP: 002b:00007f102a4aa028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f1029815fa0 RCX: 00007f102959cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f1029815fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f1029816038 R14: 00007f1029815fa0 R15: 00007ffc26833278
 </TASK>
INFO: task syz.5.225:7724 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.225       state:D stack:27160 pid:7724  tgid:7723  ppid:6403   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcf7979cdd9
RSP: 002b:00007fcf7a609028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fcf79a15fa0 RCX: 00007fcf7979cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007fcf79832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcf79a16038 R14: 00007fcf79a15fa0 R15: 00007ffdc993b0a8
 </TASK>
INFO: task syz.5.225:7725 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.5.225       state:D stack:27368 pid:7725  tgid:7723  ppid:6403   task_flags:0x400140 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x17b4/0x5680
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x6d9/0x940
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x250
 __se_sys_quotactl+0x3a7/0x9e0
 do_syscall_64+0x15f/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fcf7979cdd9
RSP: 002b:00007fcf7a5e8028 EFLAGS: 00000246 ORIG_RAX: 00000000000000b3
RAX: ffffffffffffffda RBX: 00007fcf79a16090 RCX: 00007fcf7979cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff80000100
RBP: 00007fcf79832d69 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fcf79a16128 R14: 00007fcf79a16090 R15: 00007ffdc993b0a8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cda0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5439:
 #0: ffff88810fb900a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000346b2e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
3 locks held by syz-executor/5614:
2 locks held by syz-executor/6301:
1 lock held by syz.7.207/7505:
 #0: ffff88801b3660d8 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.225/7724:
 #0: ffff88801b3660d8 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.5.225/7725:
 #0: ffff88801b3660d8 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.9.327/10358:
 #0: ffff88801b3660d8 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.383/11980:
 #0: ffff88801b3660d8 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
3 locks held by syz.7.513/13958:
1 lock held by syz.7.513/13965:

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

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+0xfd3/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x514/0xb70
 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: 6301 Comm: syz-executor 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:mark_lock+0x3/0x190
Code: 3a 90 41 89 e9 48 89 df 48 8b 2c 24 e9 b6 fd ff ff 66 0f 1f 44 00 00 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 90 55 41 57 <41> 56 41 55 41 54 53 8b 46 20 89 c1 81 e1 00 00 03 00 83 f9 01 bb
RSP: 0018:ffffc90003d875a0 EFLAGS: 00000002
RAX: 0000000000000001 RBX: ffff88810cfcbb00 RCX: ffffffff93e88ba8
RDX: 0000000000000006 RSI: ffff88810cfcc6e0 RDI: ffff88810cfcbb00
RBP: 0000000000000000 R08: ffffffff84356987 R09: ffff88810c52c3c8
R10: dffffc0000000000 R11: ffffed1003da315d R12: 0000000000000004
R13: ffff88810cfcc6e0 R14: ffff88810cfcbb00 R15: 0000000000000002
FS:  0000555594466500(0000) GS:ffff8882a9293000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f5139e9a000 CR3: 0000000107288000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 __lock_acquire+0x9f9/0x2cf0
 lock_acquire+0x106/0x350
 down_write+0x96/0x200
 f2fs_write_checkpoint+0x607/0x26a0
 kill_f2fs_super+0x314/0x730
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x33e/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f9c62b9e017
Code: a2 c7 05 dc 06 25 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007fff9e686e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007f9c62c32120 RCX: 00007f9c62b9e017
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fff9e686f10
RBP: 00007fff9e686f10 R08: 00007fff9e687f10 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fff9e687fa0
R13: 00007f9c62c32120 R14: 00000000000190a8 R15: 00007fff9e687fe0
 </TASK>
