Comment 45 for bug 430496

Documented at <https://wiki.ubuntu.com/KarmicKoala/ReleaseNotes#Optional%20encrypted%20partitions%20must%20be%20marked%20bootwait%20in%20/etc/fstab>:

In addition to the above, users who have configured any encrypted partitions in {{{/etc/crypttab}}} to start at boot time (i.e., not using the {{{noauto}}} option) should make sure that the filesystems on these volumes are listed in {{{/etc/fstab}}} if they are not mounted at a standard system mountpoint. Failure to do this on a desktop system will lead to problems from the X server and {{{cryptsetup}}} trying to control the console at the same time. At best, this will prevent the user from seeing the passphrase prompt; at worst it will also cause the X server to spin and consume 100% CPU. (Bug:430496)