INFO: task syz.1.248:7444 blocked for more than 143 seconds.
      Not tainted syzkaller #0
"echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message.
task:syz.1.248       state:D stack:26184 pid:7444  tgid:7417  ppid:5612   task_flags:0x400040 flags:0x00080002
Call Trace:
 <TASK>
 __schedule+0x1821/0x5740
 schedule+0x164/0x360
 schedule_preempt_disabled+0x13/0x30
 rwsem_down_write_slowpath+0x883/0x1080
 down_write+0x1bc/0x200
 f2fs_issue_checkpoint+0x437/0x790
 f2fs_do_sync_file+0x818/0x19e0
 __x64_sys_fsync+0x12a/0x180
 do_syscall_64+0x15f/0x560
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4dd379ce59
RSP: 002b:00007f4dd4719028 EFLAGS: 00000246 ORIG_RAX: 000000000000004a
RAX: ffffffffffffffda RBX: 00007f4dd3a16090 RCX: 00007f4dd379ce59
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 000000000000000b
RBP: 00007f4dd3832d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4dd3a16128 R14: 00007f4dd3a16090 R15: 00007ffc8feb6138
 </TASK>

Showing all locks held in the system:
1 lock held by khungtaskd/34:
 #0: ffffffff8e95cce0 (rcu_read_lock){....}-{1:3}, at: debug_show_all_locks+0x2e/0x180
4 locks held by kworker/u10:4/81:
 #0: ffff8881622ef940 ((wq_completion)writeback){+.+.}-{0:0}, at: process_scheduled_works+0xa35/0x1860
 #1: ffffc9000231fc40 ((work_completion)(&(&wb->dwork)->work)){+.+.}-{0:0}, at: process_scheduled_works+0xa70/0x1860
 #2: ffff88801f8b20d8 (&type->s_umount_key#59){++++}-{4:4}, at: super_trylock_shared+0x20/0xf0
 #3: ffff88811fca14b8 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_issue_checkpoint+0x437/0x790
2 locks held by getty/5440:
 #0: ffff8881119fd0a0 (&tty->ldisc_sem){++++}-{0:0}, at: tty_ldisc_ref_wait+0x25/0x70
 #1: ffffc900034732e8 (&ldata->atomic_read_lock){+.+.}-{4:4}, at: n_tty_read+0x45c/0x13a0
3 locks held by syz.1.248/7418:
1 lock held by syz.1.248/7444:
 #0: ffff88811fca14b8 (&sbi->gc_lock){+.+.}-{4:4}, at: f2fs_issue_checkpoint+0x437/0x790
1 lock held by syz-executor/10786:
 #0: ffffffff8e962fe8 (rcu_state.exp_mutex){+.+.}-{4:4}, at: synchronize_rcu_expedited+0x38d/0x770

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

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+0xfd3/0x1030
 kthread+0x389/0x470
 ret_from_fork+0x514/0xb70
 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: 7418 Comm: syz.1.248 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:kasan_check_range+0x5d/0x2c0
Code: cc cc 49 b9 00 00 00 00 00 00 00 ff 4c 39 cf 0f 82 14 02 00 00 49 89 ff 49 c1 ef 03 49 ba 00 00 00 00 00 fc ff df 4f 8d 1c 17 <49> ff c8 4d 89 c1 49 c1 e9 03 48 bb 01 00 00 00 00 fc ff df 4d 8d
RSP: 0018:ffffc90007a87168 EFLAGS: 00000a06
RAX: 00000000ffffff01 RBX: ffff88811fca0c18 RCX: ffffffff81a2479b
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc90007a871e0
RBP: ffffc90007a87250 R08: ffffc90007a871e4 R09: ffff800000000000
R10: dffffc0000000000 R11: fffff52000f50e3c R12: 1ffff92000f50e38
R13: ffff88811fca0c20 R14: dffffc0000000000 R15: 1ffff92000f50e3c
FS:  00007f4dd473a6c0(0000) GS:ffff88818dc87000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 000000110c339464 CR3: 000000010c54a000 CR4: 00000000000006f0
Call Trace:
 <TASK>
 do_raw_spin_lock+0x12b/0x2f0
 f2fs_write_checkpoint+0xb3b/0x26a0
 f2fs_issue_checkpoint+0x456/0x790
 f2fs_do_shutdown+0x111/0x590
 __f2fs_ioctl+0x45c7/0xbd20
 __se_sys_ioctl+0xfc/0x170
 do_syscall_64+0x15f/0x560
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
RIP: 0033:0x7f4dd379ce59
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:00007f4dd473a028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007f4dd3a15fa0 RCX: 00007f4dd379ce59
RDX: 0000200000000080 RSI: 000000008004587d RDI: 0000000000000008
RBP: 00007f4dd3832d6f R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f4dd3a16038 R14: 00007f4dd3a15fa0 R15: 00007ffc8feb6138
 </TASK>
