Comment 55 for bug 103177

The removal of evms (make sure you that you have a valid /etc/fstab and remove it when upgrading) takes care of all the /dev/mapper problems. But the race condition still exists in Gutsy:
[ 4.684000] sd 0:0:0:0: [sda] 234441648 512-byte hardware sectors (120034 MB)
...
[ 4.688000] sda: sda1 sda2 sda3 sda4
...
[ 4.956000] md: bind<sda2>
[ 4.960000] md: md1 stopped.
[ 4.964000] md: bind<sda3>
[ 4.964000] md: md0 stopped.
[ 4.964000] md: unbind<sda2>
[ 4.964000] md: export_rdev(sda2)
[ 4.972000] md: bind<sda2>
[ 5.080000] hda: SAMSUNG SP1213N, ATA DISK drive
...
[ 7.492000] hda: hda1 hda2 hda3 hda4 < hda5 hda6 hda7 >

and my RAIDs end up without the partitions from hda.