Looks like Bug #148003.
IMHO, it's a race between udev and cryptsetup (libdevmapper).
I "fixed" it by removing /etc/udev/rules.d/65-dmsetup.rules.
This file seems to have been introduced by a recent Ubuntu patch. Presumably there was a good reason for it, but it causes havoc.
Looks like Bug #148003.
IMHO, it's a race between udev and cryptsetup (libdevmapper).
I "fixed" it by removing /etc/udev/ rules.d/ 65-dmsetup. rules.
This file seems to have been introduced by a recent Ubuntu patch. Presumably there was a good reason for it, but it causes havoc.