[root@client-el8 ldiskfs]# for i in $(seq 0 2 1024); do dd if=/dev/zero of=testfile bs=4K count=1 seek=$i oflag=direct conv=notrunc; sync ; done
...
[root@client-el8 ldiskfs]# debugfs -c -R 'stat testfile' /tmp/ext4
debugfs 1.47.3-wc2 (11-Nov-2025)
Inode: 12   Type: regular    Mode:  0644   Flags: 0x80000
Generation: 109735300    Version: 0x00000000:00000001
User:     0   Group:     0   Project:     0   Size: 4198400
File ACL: 0
Links: 1   Blockcount: 4120
Fragment:  Address: 0    Number: 0    Size: 0
 ctime: 0x69c69b9c:637defc0 -- Fri Mar 27 16:00:44 2026
 atime: 0x69c69b97:814af470 -- Fri Mar 27 16:00:39 2026
 mtime: 0x69c69b9c:637defc0 -- Fri Mar 27 16:00:44 2026
crtime: 0x69c69b97:814af470 -- Fri Mar 27 16:00:39 2026
Size of extra inode fields: 32
EXTENTS:
(ETB0):33795, (0):34817, (2):36865, (4):35337,...(ETB0):34306, (680):38652, (682):38655, (684):38658...(1024):39936
[root@client-el8 ~]# umount /mnt/ldiskfs
[root@client-el8 ldiskfs]# debugfs -w /tmp/ext4
debugfs 1.47.3-wc2 (11-Nov-2025)
debugfs:  set_inode_field testfile size 4096
debugfs:  set_super_value last_orphan 12
[root@client-el8 ~]# e2fsck -v /tmp/ext4
e2fsck 1.47.3-wc2 (11-Nov-2025)
Truncating orphaned inode 12 (uid=0, gid=0, mode=0100644, size=4096)
Setting free blocks count to 2554682 (was 2554683)
/tmp/ext4: clean, 13/655360 files, 66758/2621440 blocks
[root@client-el8 ~]# e2fsck -f /tmp/ext4
e2fsck 1.47.3-wc2 (11-Nov-2025)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Pass 5: Checking group summary information
Free blocks count wrong (2554682, counted=2554683).
Fix<y>? yes

/tmp/ext4: ***** FILE SYSTEM WAS MODIFIED *****
/tmp/ext4: 13/655360 files (0.0% non-contiguous), 66757/2621440 blocks
[root@client-el8 ~]# debugfs -c -R 'stat testfile' /tmp/ext4
debugfs 1.47.3-wc2 (11-Nov-2025)
Inode: 12   Type: regular    Mode:  0644   Flags: 0x80000
Generation: 109735300    Version: 0x00000000:00000001
User:     0   Group:     0   Project:     0   Size: 4096
File ACL: 0
Links: 1   Blockcount: 16
Fragment:  Address: 0    Number: 0    Size: 0
 ctime: 0x69c69b9c:637defc0 -- Fri Mar 27 16:00:44 2026
 atime: 0x69c69b97:814af470 -- Fri Mar 27 16:00:39 2026
 mtime: 0x69c69b9c:637defc0 -- Fri Mar 27 16:00:44 2026
crtime: 0x69c69b97:814af470 -- Fri Mar 27 16:00:39 2026
Size of extra inode fields: 32
EXTENTS:
(ETB0):33795, (0):34817

[root@client-el8 ldiskfs]# setfattr -n user.lala -v "$(for ((i=0; i < 4096*2; i++)); do echo -n a; done)" toto
[root@client-el8 ldiskfs]# debugfs -c -R 'stat toto' /tmp/ext4 
debugfs 1.47.3-wc2 (11-Nov-2025)
Inode: 12   Type: regular    Mode:  0644   Flags: 0x80000
Generation: 1419816429    Version: 0x00000000:00000001
User:     0   Group:     0   Project:     0   Size: 0
File ACL: 0
Links: 1   Blockcount: 16
Fragment:  Address: 0    Number: 0    Size: 0
 ctime: 0x69c6925a:c64cda70 -- Fri Mar 27 15:21:14 2026
 atime: 0x69c6924d:7b31d064 -- Fri Mar 27 15:21:01 2026
 mtime: 0x69c6924d:7b31d064 -- Fri Mar 27 15:21:01 2026
crtime: 0x69c6924d:7b31d064 -- Fri Mar 27 15:21:01 2026
Size of extra inode fields: 32
Extended attributes:
  inode <13> user.lala (8192)
EXTENTS:
[root@client-el8 ~]# umount /tmp/ext4
[root@client-el8 ~]# debugfs -w /tmp/ext4
debugfs 1.47.3-wc2 (11-Nov-2025)
debugfs:  set_super_value last_orphan 12
debugfs:  set_inode_field toto links_count 0              
debugfs:  unlink toto
[root@client-el8 ~]# e2fsck -f -vvvv /tmp/ext4                                
e2fsck 1.47.3-wc2 (11-Nov-2025)
Clearing orphaned inode 12 (uid=0, gid=0, mode=0100644, size=0)
Pass 1: Checking inodes, blocks, and sizes
Pass 2: Checking directory structure
Pass 3: Checking directory connectivity
Pass 4: Checking reference counts
Regular filesystem inode 13 has EA_INODE flag set. Clear<y>? yes
Unattached inode 13
Connect to /lost+found<y>? yes
Inode 13 ref count is 2, should be 1.  Fix<y>? yes
Pass 5: Checking group summary information

/tmp/ext4: ***** FILE SYSTEM WAS MODIFIED *****

          12 inodes used (0.00%, out of 655360)
           0 non-contiguous files (0.0%)
           0 non-contiguous directories (0.0%)
             # of inodes with ind/dind/tind blocks: 0/0/0
             Extent depth histogram: 4
       66755 blocks used (2.55%, out of 2621440)
           0 bad blocks
           1 large file

           1 regular file
           2 directories
           0 character device files
           0 block device files
           0 fifos
           0 links
           0 symbolic links (0 fast symbolic links)
           0 sockets
------------
           2 files