Comment 13 for bug 719129

If dmraid does not create the base disk device, then yes, kpartx has nothing to do. The problem arises when dmraid has activated the array, and creates the partitions with one name scheme, and then kpartx is run and tries to use another scheme. If dmraid does not add the 'p' and kpartx does, then kpartx ends up creating duplicate devices for the partitions with the 'p', so you have one with, and one without.

Now that libparted has the functionality, shouldn't it be removed from gparted, rather than duplicating it? If it is going to duplicate it, then it should at least do it the same way. Long term it seems like the whole DMRaid.cc module could go away and go back to letting libparted handle things, since it does so correctly now. If gparted wants to be able to work with older versions of libparted, then perhaps it could be made a configuration option?

As for fixing this bug for Natty, it looks like the -P argument needs dropped, and gparted needs to add the 'p'. Parted and dmraid also could be patched to add the 'p' only if the previous character is a digit. Does that sound like a reasonable simple fix for now?