RE: 2.6 kernel failing lofs mount from lsb-runtime-test

> Appears to be true. md5sum of my backup and the original file differ, 
> after the failed run. (4 unresolved - mini streamio run)

Well, it /is/ written to, if only to update inode times,
so I wouldn't expect it to be identical.

> losetup -d /dev/loop0 doesn't work, I get
> 
> ioctl: LOOP_CLR_FD: Device or resource busy

This would seem to be what Chis observed: it won't unmount.

> A reboot into a 2.4 kernel with the modified loopback_disk.ext2
> generates failures.  Same mount points in /proc/mounts.

Any chance there are incompatible changes in the ext2
filesystem module between 2.4 and 2.6?  I guess you
would have seen this with other filesystems, though.