F2FS-fs (loop0): Disable nat_bits due to incorrect cp_ver (13274671252798256465, 0)
F2FS-fs (loop0): Try to recover 2th superblock, ret: 0
F2FS-fs (loop0): Mounted with checkpoint version = 15213551
============================================
WARNING: possible recursive locking detected
5.17.0-rc1-syzkaller #0 Not tainted
--------------------------------------------
syz-executor288/4062 is trying to acquire lock:
ffff888017bc4390 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2149 [inline]
ffff888017bc4390 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_write_checkpoint+0x466/0x5ae0 fs/f2fs/checkpoint.c:1615

but task is already holding lock:
ffff888017bc5338 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2149 [inline]
ffff888017bc5338 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_issue_checkpoint+0x2a0/0x430 fs/f2fs/checkpoint.c:1834

other info that might help us debug this:
 Possible unsafe locking scenario:

       CPU0
       ----
  lock(&sem->internal_rwsem#2);
  lock(&sem->internal_rwsem#2);

 *** DEADLOCK ***

 May be due to missing lock nesting notation

2 locks held by syz-executor288/4062:
 #0: ffff888076f680e0 (&type->s_umount_key#50){+.+.}-{3:3}, at: deactivate_super+0x5f/0x80 fs/super.c:362
 #1: ffff888017bc5338 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_down_write fs/f2fs/f2fs.h:2149 [inline]
 #1: ffff888017bc5338 (&sem->internal_rwsem#2){++++}-{3:3}, at: f2fs_issue_checkpoint+0x2a0/0x430 fs/f2fs/checkpoint.c:1834

stack backtrace:
CPU: 0 PID: 4062 Comm: syz-executor288 Not tainted 5.17.0-rc1-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x57/0x7d lib/dump_stack.c:106
 print_deadlock_bug kernel/locking/lockdep.c:2956 [inline]
 check_deadlock kernel/locking/lockdep.c:2999 [inline]
 validate_chain kernel/locking/lockdep.c:3788 [inline]
 __lock_acquire.cold+0x12c/0x3a9 kernel/locking/lockdep.c:5027
 lock_acquire kernel/locking/lockdep.c:5639 [inline]
 lock_acquire+0x1ab/0x510 kernel/locking/lockdep.c:5604
 down_write+0x90/0x150 kernel/locking/rwsem.c:1514
 f2fs_down_write fs/f2fs/f2fs.h:2149 [inline]
 f2fs_write_checkpoint+0x466/0x5ae0 fs/f2fs/checkpoint.c:1615
 __write_checkpoint_sync fs/f2fs/checkpoint.c:1745 [inline]
 f2fs_issue_checkpoint+0x2ad/0x430 fs/f2fs/checkpoint.c:1842
 sync_filesystem fs/sync.c:63 [inline]
 sync_filesystem+0x15c/0x1f0 fs/sync.c:30
 generic_shutdown_super+0x64/0x3a0 fs/super.c:445
 kill_block_super+0x90/0xd0 fs/super.c:1394
 kill_f2fs_super+0x241/0x340 fs/f2fs/super.c:4523
 deactivate_locked_super+0x7b/0x130 fs/super.c:332
 cleanup_mnt+0x324/0x4d0 fs/namespace.c:1143
 task_work_run+0xc0/0x160 kernel/task_work.c:164
 exit_task_work include/linux/task_work.h:32 [inline]
 do_exit+0x9a6/0x2500 kernel/exit.c:806
 do_group_exit+0xb2/0x2a0 kernel/exit.c:935
 __do_sys_exit_group kernel/exit.c:946 [inline]
 __se_sys_exit_group kernel/exit.c:944 [inline]
 __x64_sys_exit_group+0x35/0x40 kernel/exit.c:944
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fbcb9731929
Code: Unable to access opcode bytes at RIP 0x7fbcb97318ff.
RSP: 002b:00007fff0bd71888 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7