# mkfs.ext4 /dev/loop0 100M # adjust if necessary, should be less than partition size Superblock backups stored on blocks: 8193, 24577, 40961, 57345, 73729 (pick one) # mount -t ext4 -o sb=40961 /dev/loop0 /media/ # resize2fs /dev/loop0 resize2fs 1.42.12 (29-Aug-2014) Filesystem at /dev/loop0 is mounted on /media; on-line resizing required old_desc_blocks = 1, new_desc_blocks = 4 Now, depending on your luck, various things may happen. resize2fs may hang. You might see BUG() in your dmesg. Either way, system will become severely corrupted (as indicated by fsck). You won't be able to mount it, either. [ 2669.510800] EXT4-fs (loop0): resizing filesystem from 128000 to 256000 blocks [ 2669.513558] EXT4-fs warning (device loop0): reserve_backup_gdb:969: reserved block 32770 not at offset 1 [ 2669.513569] EXT4-fs (loop0): resized filesystem to 256000 [ 2669.516328] EXT4-fs warning (device loop0): ext4_group_extend:1734: can't shrink FS - resize aborted -- Maxim Malkov Software Engineering Department, ISPRAS -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html