initramfs fails to mount LUKS root partition after upgrade to Quantal

[GOo]

After upgrading to 12.10 via "do-release-upgrade", I am no more able to boot. Previously I was able to boot with the same setup since Ubuntu 10.10.

My /, /home, /var and /mnt/media partitions are LUKS encrypted LVs on top of RAID10,RAID1 md arrays and accessed via a key-file on a usb-stick.
/boot is on an unencrypted md (md0).

What I would have expected is cryptsetup mapping the encrypted volumes, mounting them and normal boot of the system.
Actually cryptroot unlocks the key slot of the root filesystem (cryptsetup: cryptroot setup successfully) but it gets stuck on waiting for the root filesystem.

WORKAROUND:
Boot in recovery mode. Wait for the timeout for the root fs to finish. In the recovery menu select "root" to access the root shell.
Eventually the root filesystem is mounted after the failure hooks and I am able to boot by typing:

# mount / -o remount,rw
# mount /boot
# mount /mnt/keydev
# cryptsetup -d /mnt/keydev/keys/darkgoo/data-media luksOpen /dev/mapper/data-media data-media_crypt
# cryptsetup -d /mnt/keydev/keys/darkgoo/data-homes luksOpen /dev/mapper/data-homes data-homes_crypt
# cryptsetup -d /mnt/keydev/keys/darkgoo/data-var luksOpen /dev/mapper/data-var data-var_crypt
# mount /home
# mount /var
# mount /media
# exit

Select menu item "resume".
The system now boots succesfully.

#lsb_release -rd
Description: Ubuntu 12.10
Release: 12.10

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: initramfs-tools 0.103ubuntu0.2 [modified: usr/share/initramfs-tools/scripts/local]
ProcVersionSignature: Ubuntu 3.5.0-18.29-generic 3.5.7
Uname: Linux 3.5.0-18-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.6.1-0ubuntu6
Architecture: amd64
Date: Sat Oct 27 20:30:50 2012
EcryptfsInUse: Yes
InstallationDate: Installed on 2010-08-23 (796 days ago)
InstallationMedia: Kubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100427)
MarkForUpload: True
PackageArchitecture: all
ProcEnviron:
 LANGUAGE=en_US
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_US.utf8
 SHELL=/bin/bash
SourcePackage: initramfs-tools
UpgradeStatus: Upgraded to quantal on 2012-10-19 (8 days ago)
mtime.conffile..etc.initramfs.tools.initramfs.conf: 2012-03-07T06:09:36.142811
mtime.conffile..etc.initramfs.tools.update.initramfs.conf: 2010-09-04T17:39:23.260572

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Matthias Kretz (mkretz)]

I did a new install of 12.10 and experienced the same bug. I found a simple workaround: Create an empty file /etc/initramfs-tools/conf.d/cryptroot . Afterwards mkinitramfs will do the right thing and fill this file with the right data.

[GOo (goo)]

Unfortunatly that did not work for me. I'm experiencing the same behavior as before also with kernel 3.5.0-19-generic.

[dknollman (dknollman)]

I have a similar problem.
initramfs hangs and my hard drive light goes off.
Typing "exit" resumes the boot.