Comment 28 for bug 725408

Phillip, in post # 23 you say "1) ntfs-3g canonicalizes the name so that if you mount with /dev/mapper/foo, the device name listed in mtab is /dev/dm-n, so you can not umount /dev/mapper/foo"

A similar remark has just been posted to the ntfs-3g forum http://tuxera.com/forum/viewtopic.php?f=3&t=27391&sid=cbf10a9a3e0fce875eebb4605ef24028 What ntfs-3g does to the device name is limited to removing occurrences of ".." and "." in the device path, and resolving symbolic links for security reasons. Is "/dev/mapper/foo" a symbolic link to "/dev/dm-n" ? If so, the proper fix is to have it accepted by umount, instead of working it around in all filesystem drivers.