The ext2fs translator from the upstream Hurd code base can only handle file
systems with sizes of less than roughly 2 GiB.
A patch exists to lift this limitation (and is being used in the
Debian GNU/Hurd distribution), but it introduces another
incompatibility: ext2fs then only supports block sizes of 4096 bytes.
Smaller block sizes are commonly automatically selected by mke2fs when using
small backend stores, like floppy devices.