INFO: task syz.1.986:16478 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.986       state:D stack:22496 pid:16478 tgid:16477 ppid:13002  task_flags:0x400140 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: 0033:0x7f629219c799
RSP: 002b:00007f6292f86028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f6292415fa0 RCX: 00007f629219c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6292415fa0 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6292416038 R14: 00007f6292415fa0 R15: 00007ffd51b60c88
 </TASK>
INFO: task syz.1.986:16598 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.986       state:D stack:28832 pid:16598 tgid:16477 ppid:13002  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: 0033:0x7f629219c799
RSP: 002b:00007f62903f6028 EFLAGS: 00000246 ORIG_RAX: 00000000000000a2
RAX: ffffffffffffffda RBX: 00007f6292416090 RCX: 00007f629219c799
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000
RBP: 00007f6292416090 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f6292416128 R14: 00007f6292416090 R15: 00007ffd51b60c88
 </TASK>

Showing all locks held in the system:
5 locks held by kworker/u9:0/26:
1 lock held by khungtaskd/34:
 #0: ffffffff8e75e520 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
3 locks held by kworker/u10:4/83:
 #0: ffff888162297948 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0x9ea/0x1830
 #1: ffffc900017dfc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa25/0x1830
 #2: ffff88810f5e20e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
2 locks held by getty/5636:
 #0: ffff88811161c0a0 (&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
1 lock held by udevd/5820:
3 locks held by syz-executor/11335:
1 lock held by syz.1.986/16478:
 #0: ffff888113a5e0e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.1.986/16598:
 #0: ffff888113a5e0e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
1 lock held by syz.4.1228/21782:
 #0: ffff88810f5e2420 (sb_writers#18){.+.+}-{0:0}, at: mnt_want_write_file+0x60/0x200
2 locks held by f2fs_ckpt-7:4/21806:
1 lock held by syz.9.1261/22749:
 #0: ffff888113a5e0e0 (&type->s_umount_key#65){++++}-{4:4}, at: super_lock+0x2d6/0x3d0
2 locks held by syz.1.1408/24321:
2 locks held by syz.0.1409/24332:
3 locks held by syz.5.1407/24334:

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

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+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: 24334 Comm: syz.5.1407 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:vprintk_emit+0x45d/0x560
Code: 0f 84 44 ff ff ff e8 42 2d 21 00 fb eb 44 e8 3a 2d 21 00 e8 55 73 09 0a 4d 85 f6 74 94 e8 2b 2d 21 00 fb 48 c7 c7 60 09 75 8e <31> f6 ba 01 00 00 00 31 c9 41 b8 01 00 00 00 45 31 c9 53 e8 cb 16
RSP: 0018:ffffc900076ff180 EFLAGS: 00000287
RAX: ffffffff81a46f45 RBX: ffffffff81a46dbf RCX: 0000000000080000
RDX: ffffc90008303000 RSI: 0000000000054235 RDI: ffffffff8e750960
RBP: ffffc900076ff230 R08: ffffffff90118cb7 R09: 1ffffffff2023196
R10: dffffc0000000000 R11: fffffbfff2023197 R12: 0000000000000000
R13: 000000000000004c R14: 0000000000000200 R15: 1ffff92000edfe34
FS:  00007f6f725f66c0(0000) GS:ffff88818de63000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f8cd81ffc00 CR3: 000000016a53a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 _printk+0xdd/0x130
 f2fs_printk+0x48a/0x520
 f2fs_recover_fsync_data+0x2c3/0x8b80
 f2fs_fill_super+0x68d0/0x7740
 get_tree_bdev_flags+0x431/0x4f0
 vfs_get_tree+0x92/0x2a0
 do_new_mount+0x341/0xd30
 __se_sys_mount+0x31d/0x420
 do_syscall_64+0x14d/0xf80
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f6f7439da0a
Code: 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8 ff ff ff ff c3 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f6f725f5e58 EFLAGS: 00000246 ORIG_RAX: 00000000000000a5
RAX: ffffffffffffffda RBX: 00007f6f725f5ee0 RCX: 00007f6f7439da0a
RDX: 0000200000000140 RSI: 00002000000000c0 RDI: 00007f6f725f5ea0
RBP: 0000200000000140 R08: 00007f6f725f5ee0 R09: 000000000101880a
R10: 000000000101880a R11: 0000000000000246 R12: 00002000000000c0
R13: 00007f6f725f5ea0 R14: 000000000000550b R15: 0000200000000400
 </TASK>
