System crashes on lid close and screensaver

[Lee H]

On Ubuntu 12.04.3 LTS on a Lenovo Thinkpad S540.

Upon closing the lid or leaving the laptop unattended for a certain time (such that the screen dims and re-login is required), the
system freezes. The mouse can still be moved, but clicks do nothing and keyboard is non responsive.

It possible to recover by ALT+CTRL+F1 then ALT+CTRL+F7, at which point the login prompt is presented and active.

My power settings are set to "Don't suspend" (battery and AC) and "Do nothing when the lid is closed" (battery and AC), so I expect nothing to happen when closing the lid. From the dimmed screen, I expect to be able to re-login with the system freezing.

I've attached also the results from doing `Alt+SysRq+1` then `Alt+SysRq+t` at the tty
, dumping into kern.log. The file is called "trace dump".

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: xserver-xorg-lts-raring 1:7.7+1ubuntu4~precise1
ProcVersionSignature: Ubuntu 3.8.0-34.49~precise1-generic 3.8.13.12
Uname: Linux 3.8.0-34-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu17.6
Architecture: amd64
Date: Thu Dec 26 02:11:26 2013
InstallationMedia: Ubuntu 12.04.3 LTS "Precise Pangolin" - Release amd64 (20130820.1)
MarkForUpload: True
ProcEnviron:
 LANGUAGE=en_GB:en
 TERM=xterm
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/bash
SourcePackage: xorg-lts-raring
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[penalvch (penalvch)]

Lee H, thank you for reporting this and helping make Ubuntu better. Please execute the following command, as it will automatically gather debugging information, in a terminal:
apport-collect 1264196

[Launchpad Janitor (janitor)]

[Expired for linux (Ubuntu) because there has been no activity for 60 days.]