I upgraded to 12.10 from 12.04 yesterday. The system has frozen 3 times since then. The 'freeze' is gradual - at first windows become unresponsive, or intermittently unresponsive. Then it is not possible to switch to an alternative window. Then the pointer freezes. It is not possible to switch to a TTY terminal at this point either.
On one occasion I had a TTY open and was able to see that Compiz was using 100% CPU. I killed Compiz and, whilst this ruined my desktop session, the pointer unfroze.
ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: xorg 1:7.7+1ubuntu4
ProcVersionSignature: Ubuntu 3.5.0-26.42-generic 3.5.7.6
Uname: Linux 3.5.0-26-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.6.1-0ubuntu10
Architecture: amd64
Date: Tue Apr 2 10:42:48 2013
DistroCodename: quantal
DistroVariant: ubuntu
GpuHangFrequency: Several times a day
InstallationDate: Installed on 2010-04-03 (1094 days ago)
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Beta amd64 (20100318)
MarkForUpload: True
ProcEnviron:
PATH=(custom, no user)
XDG_RUNTIME_DIR=<set>
LANG=en_GB.UTF-8
SHELL=/bin/bash
SourcePackage: xorg
Symptom: display
Title: Xorg freeze
UpgradeStatus: Upgraded to quantal on 2013-04-01 (0 days ago)
I presume when it locks up to the point of un-usability, the only way out is a reboot?
If so, when you boot back up, can you login from a console and grab the ~/.xsession-errors and attach it to this bug report. You can also collect data about your system to make it easier to diagnose using the following command:-
apport-collect 1163209
I'd also run this just to make sure nothing went missing during the upgrade from 12.04 to 12.10 (note the caret):-
sudo apt-get install ubuntu-desktop^