INFO: task syz.0.110:6521 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.110       state:D stack:28536 pid:6521  tgid:6520  ppid:5811   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c93b9cdd9
RSP: 002b:00007f7c94a10028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f7c93e15fa0 RCX: 00007f7c93b9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f7c93e15fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7c93e16038 R14: 00007f7c93e15fa0 R15: 00007ffd2f06c4d8
 </TASK>
INFO: task syz.0.110:6522 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.0.110       state:D stack:28832 pid:6522  tgid:6520  ppid:5811   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x15dd/0x52d0
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_read_slowpath+0x61e/0x920
 down_read+0x99/0x2e0
 super_lock+0x2d6/0x3d0
 __iterate_supers+0x126/0x290
 __ia32_sys_sync+0xa0/0x120
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f7c93b9cdd9
RSP: 002b:00007f7c949ef028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f7c93e16090 RCX: 00007f7c93b9cdd9
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f7c93e16090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f7c93e16128 R14: 00007f7c93e16090 R15: 00007ffd2f06c4d8
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/35:
 #0: ffffffff8e75e5e0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
2 locks held by getty/5636:
 #0: ffff888113d790a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc9000356e2f0 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13c0
4 locks held by syz-executor/5819:
1 lock held by syz.0.110/6521:
 #0: ffff8881123020e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.0.110/6522:
 #0: ffff8881123020e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.1.182/6961:
 #0: ffff8881123020e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.6.456/8514:
 #0: ffff8881123020e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.6.456/8517:
 #0: ffff8881123020e0 (&type->s_umount_key#54){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz.7.598/9431:
2 locks held by syz.4.599/9435:

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

NMI backtrace for cpu 1
CPU: 1 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+0xfd9/0x1030
 kthread+0x388/0x470
 ret_from_fork+0x51e/0xb90
 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: 5819 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:__lock_acquire+0x869/0x2cf0
Code: c1 c2 06 31 da 01 c1 29 d0 89 d6 c1 c6 08 31 c6 01 ca 29 f1 89 f3 c1 c3 10 31 cb 01 d6 29 da 89 dd c1 c5 13 31 d5 01 f3 29 ee <01> eb c1 c5 04 31 f5 48 c1 e5 20 83 3d 79 68 70 0e 00 4d 89 e5 0f
RSP: 0018:ffffc900063673c8 EFLAGS: 00000083
RAX: 0000000080107eb7 RBX: 0000000029e458b5 RCX: 000000002ae6f883
RDX: 00000000888b2b31 RSI: 00000000f4066979 RDI: ffff88816c430000
RBP: 0000000056d5d371 R08: ffffffff82519814 R09: ffff8881babba578
R10: ffffc90006367620 R11: fffff52000c6cef2 R12: ffff88816c430ba8
R13: ffff88816c430ba8 R14: ffff88816c430000 R15: 0000000000000002
FS:  0000555587911500(0000) GS:ffff88818de57000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c38907b CR3: 0000000172194000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 lock_acquire+0xf0/0x2e0
 _raw_spin_lock+0x2e/0x40
 writeback_single_inode+0x34/0xdc0
 sync_inode_metadata+0x122/0x1d0
 f2fs_write_checkpoint+0xb93/0x26a0
 kill_f2fs_super+0x314/0x720
 deactivate_locked_super+0xbc/0x130
 cleanup_mnt+0x437/0x4d0
 task_work_run+0x1d9/0x270
 exit_to_user_mode_loop+0xed/0x480
 do_syscall_64+0x32d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7fe2ff59e017
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:00007ffd205f2798 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 00007fe2ff632120 RCX: 00007fe2ff59e017
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffd205f2850
RBP: 00007ffd205f2850 R08: 00007ffd205f3850 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffd205f38e0
R13: 00007fe2ff632120 R14: 00000000000131bf R15: 00007ffd205f3920
 </TASK>
