If X fails to start, Plymouth should redirect to a command line login

[Julien Aubin]

Hi,

After purge of old packages with command "sudo aptitude purge ~c" on Trusty 14.04.2 LTS on two of my systems, the system did not boot, it was locked on Plymouth splash screen.

The culprit is that for a reason I don't know symlink /etc/X11/X was removed during the upgrade, and X failed to start.

In that case Plymouth should just fall back to a prompt shell login, otherwise there's no way to log onto the machine except SSH...

Steps to reproduce :
DO : Remove symlink /etc/X11/X (it occurs sometimes during kernel upgrades, I did not identify the culprit but this is not the first time I see this)
DO : Reboot
EXPECT : After a failed attempt to start X, Plymouth should fall back to the command prompt
ACTUAL : The user is locked up and the only ways to recover are to log via SSH or in failsafe mode.

The best would be to fix the original bug, i.e. symlink to X deleted when purging old packages. This can occur on Ubuntu LTS upgraded w/ HWE as the xserver-xorg package changed, while this won't occur on other systems.

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: plymouth 0.8.8-0ubuntu17.1
ProcVersionSignature: Ubuntu 3.16.0-36.48~14.04.1-generic 3.16.7-ckt9
Uname: Linux 3.16.0-36-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.14.1-0ubuntu3.10
Architecture: amd64
CurrentDesktop: KDE
Date: Wed Apr 29 20:28:50 2015
DefaultPlymouth: /lib/plymouth/themes/kubuntu-logo/kubuntu-logo.plymouth
InstallationDate: Installed on 2014-09-08 (233 days ago)
InstallationMedia: Kubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140416.1)
MachineType: ASUS All Series
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-36-generic root=UUID=ef1513cf-ddee-4714-bc0b-a7f84529908e ro quiet splash
ProcFB:

ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.16.0-36-generic root=UUID=ef1513cf-ddee-4714-bc0b-a7f84529908e ro quiet splash
SourcePackage: plymouth
TextPlymouth: /lib/plymouth/themes/kubuntu-text/kubuntu-text.plymouth
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 02/12/2015
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2205
dmi.board.asset.tag: To be filled by O.E.M.
dmi.board.name: Z97-A
dmi.board.vendor: ASUSTeK COMPUTER INC.
dmi.board.version: Rev 1.xx
dmi.chassis.asset.tag: To Be Filled By O.E.M.
dmi.chassis.type: 3
dmi.chassis.vendor: To Be Filled By O.E.M.
dmi.chassis.version: To Be Filled By O.E.M.
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2205:bd02/12/2015:svnASUS:pnAllSeries:pvrSystemVersion:rvnASUSTeKCOMPUTERINC.:rnZ97-A:rvrRev1.xx:cvnToBeFilledByO.E.M.:ct3:cvrToBeFilledByO.E.M.:
dmi.product.name: All Series
dmi.product.version: System Version
dmi.sys.vendor: ASUS