EXT4-fs (loop0): mounted filesystem without journal. Opts: ,errors=continue
EXT4-fs error (device loop0): __ext4_new_inode:930: comm syz-executor470: reserved inode found cleared - inode=1
incfs: Can't find or create .index dir in ./file0
BUG: Dentry ffff8881ecb99990{i=0,n=.index}  still in use (1) [unmount of ext4 loop0]
------------[ cut here ]------------
WARNING: CPU: 0 PID: 347 at fs/dcache.c:1597 umount_check+0x179/0x1c0 fs/dcache.c:1588
Modules linked in:
CPU: 0 PID: 347 Comm: syz-executor470 Not tainted 5.4.125-syzkaller-00030-g1e429b8f9eb9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:umount_check+0x179/0x1c0 fs/dcache.c:1588
Code: ff 4c 8b 0b 48 81 c5 20 04 00 00 48 c7 c7 a0 08 e9 84 4c 89 fe 4c 89 f2 4c 89 f9 45 89 e8 31 c0 55 e8 07 a2 af ff 48 83 c4 08 <0f> 0b e9 fd fe ff ff 89 e9 80 e1 07 80 c1 03 38 c1 0f 8c d4 fe ff
RSP: 0018:ffff8881e5a5fa58 EFLAGS: 00010282
RAX: 0000000000000054 RBX: ffffffff85faa1c0 RCX: 5d853390c599d000
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 0000000000000000
RBP: ffff8881dae68420 R08: ffffffff814e90e7 R09: ffffed103edc9608
R10: ffffed103edc9608 R11: 0000000000000000 R12: dffffc0000000000
R13: 0000000000000001 R14: 0000000000000000 R15: ffff8881ecb99990
FS:  00005555561d0300(0000) GS:ffff8881f6e00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f559c58c1d0 CR3: 0000000005e0e000 CR4: 00000000003406f0
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 do_one_tree fs/dcache.c:1604 [inline]
 shrink_dcache_for_umount+0x8a/0x1a0 fs/dcache.c:1620
 kill_block_super+0x79/0xd0 fs/super.c:1444
 deactivate_locked_super+0xaf/0x100 fs/super.c:335
 cleanup_mnt+0x432/0x4e0 fs/namespace.c:1102
 exit_task_work include/linux/task_work.h:22 [inline]
 do_exit+0xcb9/0x2bf0 kernel/exit.c:812
 do_group_exit+0x15c/0x2c0 kernel/exit.c:910
 __do_sys_exit_group+0x13/0x20 kernel/exit.c:921
 __se_sys_exit_group+0x10/0x10 kernel/exit.c:919
 __x64_sys_exit_group+0x37/0x40 kernel/exit.c:919
 do_syscall_64+0xcb/0x1e0 arch/x86/entry/common.c:290
 entry_SYSCALL_64_after_hwframe+0x44/0xa9
RIP: 0033:0x7f559c5170a9
Code: Bad RIP value.
RSP: 002b:00007ffe40c354c8 EFLAGS: 00000246 ORIG_RAX: 00000000000000e7
RAX: ffffffffffffffda RBX: 00007f559c58b330 RCX: 00007f559c5170a9
RDX: 000000000000003c RSI: 00000000000000e7 RDI: 0000000000000001
RBP: 0000000000000001 R08: ffffffffffffffc0 R09: 00007f559c585e40
R10: 0000000000000000 R11: 0000000000000246 R12: 00007f559c58b330
R13: 0000000000000001 R14: 0000000000000000 R15: 0000000000000001
---[ end trace 8bd8cc4c97358d1c ]---
VFS: Busy inodes after unmount of loop0. Self-destruct in 5 seconds.  Have a nice day...