Unable to boot due to all processes terminated with status 255

After upgrading to 14.04, I find myself unable to fully boot. All of my processes are then killed with status 255:

[4.099638] init: hwclock main process (232) terminated with status 255
[4.099638] init: startpar-bridge (hostname--stopped) main process (240) terminated with status 255
[4.099638] init: startpar-bridge (ureadahead--stopped) main process (241) terminated with status 255
[4.099638] init: startpar-bridge (plymouth-upstart-bridge--stopped) main process (242) terminated with status 255

etc...

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: mountall 2.53
ProcVersionSignature: Ubuntu 3.19.0-25.26~14.04.1-generic 3.19.8-ckt2
Uname: Linux 3.19.0-25-generic x86_64
.run.mount.utab:

ApportVersion: 2.14.1-0ubuntu3.21
Architecture: amd64
Date: Tue Oct 11 09:28:02 2016
InstallationDate: Installed on 2015-09-02 (405 days ago)
InstallationMedia: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
Mounts: Error: command ['mount'] failed with exit code 255:
ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcKernelCmdline: BOOT_IMAGE=/vmlinuz-3.19.0-25-generic root=/dev/mapper/ubuntu--vg-root ro recovery nomodeset
SourcePackage: mountall
UpgradeStatus: No upgrade log present (probably fresh install)