There is a bad bug in the ext2 file system, namely the fact
that the magic number is not stored in the same relative
position as minix uses.
This is not really a bug in the ext2 filesystem --- *all* of the
filesystems store their magic numbers at different offsets.
A clean solution to all of this would be to have the genhd code store
the partition type code in the partition table along with all of the
rest of the partition table's vital statistics, and then have the root
filesystem autodetection code use that type code as a hint to see which
filesystem it should try to mount first.
- Ted