desktop/unity/active programme locks up and won't respond

[SimonC]

I think this is related to lightdm but I'm not 100% certain.

Periodically the desktop (i.e. Unity and whatever programmes I have open) locks up. I can move the mouse but clicking has no effect. I can switch to a terminal with ctrl-alt-1 etc. After a bit of trial and error I discovered that restarting lightdm (sudo service lightdm restart) got me back to a working GUI.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: lightdm 1.2.1-0ubuntu1.1
ProcVersionSignature: Ubuntu 3.2.0-31.50-generic 3.2.28
Uname: Linux 3.2.0-31-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.0.1-0ubuntu13
Architecture: amd64
Date: Fri Oct 12 23:25:36 2012
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release amd64 (20111012)
SourcePackage: lightdm
UpgradeStatus: Upgraded to precise on 2012-06-17 (117 days ago)