Xorg crash - black screen then redirected to login

[Budoc]

I assume that this is an xorg problem. I was browsing the internet when suddenly my screen went black and eventually I was redirected back to the login screen. After this happened, I logged back in and ran ubuntu-bug. This is the first time that this has happened, so I do not know how to reproduce this bug.

lsb_release -rd
Description: Ubuntu 12.04.1 LTS
Release: 12.04

xorg:
  Installed: 1:7.6+12ubuntu1
  Candidate: 1:7.6+12ubuntu1
  Version table:
 *** 1:7.6+12ubuntu1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ precise/main i386 Packages
        100 /var/lib/dpkg/status

What I'd expect to happen: not getting a black screen and after a while getting redirected to the login screen.
What happened instead: getting a black screen and then redirected to the login screen.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: xorg 1:7.6+12ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-31.50-generic-pae 3.2.28
Uname: Linux 3.2.0-31-generic-pae i686
.tmp.unity.support.test.0:

ApportVersion: 2.0.1-0ubuntu13
Architecture: i386
CompizPlugins: [core,composite,opengl,compiztoolbox,decor,vpswitch,snap,mousepoll,resize,place,move,wall,grid,regex,imgpng,session,gnomecompat,animation,fade,unitymtgrabhandles,workarounds,scale,expo,ezoom,unityshell]
CompositorRunning: compiz
Date: Sat Sep 29 09:28:59 2012
DistUpgraded: Fresh install
DistroCodename: precise
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, if not too technical
GraphicsCard:
 Intel Corporation Mobile 915GM/GMS/910GML Express Graphics Controller [8086:2592] (rev 03) (prog-if 00 [VGA controller])
   Subsystem: Toshiba America Info Systems Device [1179:ff04]
   Subsystem: Toshiba America Info Systems Device [1179:ff04]
InstallationMedia: Ubuntu 12.04.1 LTS "Precise Pangolin" - Release i386 (20120817.3)
Lsusb:
 Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
 Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
 Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
MachineType: TOSHIBA 00000000000000000000
PccardctlIdent:
 Socket 0:
   no product info available
PccardctlStatus:
 Socket 0:
   no card
ProcEnviron:
 LANGUAGE=en_GB:en
 PATH=(custom, no user)
 LANG=en_GB.UTF-8
 SHELL=/bin/zsh
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.2.0-31-generic-pae root=UUID=1fb109ba-28e6-439d-b8c8-97f42c743407 ro quiet splash vt.handoff=7
SourcePackage: xorg
Symptom: display
Title: Xorg crash
UpgradeStatus: No upgrade log present (probably fresh install)
dmi.bios.date: 12/26/2005
dmi.bios.vendor: TOSHIBA
dmi.bios.version: V1.30
dmi.board.name: HTW00
dmi.board.vendor: TOSHIBA
dmi.board.version: Null
dmi.chassis.asset.tag: *
dmi.chassis.type: 10
dmi.chassis.vendor: TOSHIBA
dmi.chassis.version: N/A
dmi.modalias: dmi:bvnTOSHIBA:bvrV1.30:bd12/26/2005:svnTOSHIBA:pn00000000000000000000:pvr0000000000000000:rvnTOSHIBA:rnHTW00:rvrNull:cvnTOSHIBA:ct10:cvrN/A:
dmi.product.name: 00000000000000000000
dmi.product.version: 0000000000000000
dmi.sys.vendor: TOSHIBA
version.compiz: compiz 1:0.9.7.8-0ubuntu1.4
version.libdrm2: libdrm2 2.4.32-1ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 8.0.3+8.0.2-0ubuntu3.2
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 8.0.3+8.0.2-0ubuntu3.2
version.xserver-xorg-core: xserver-xorg-core 2:1.11.4-0ubuntu10.8
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.0-0ubuntu1.2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.14.99~git20111219.aacbd629-0ubuntu2
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.17.0-1ubuntu4.1
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:0.0.16+git20111201+b5534a1-1build2

[Chris Wilson (ickle)]

Resource leak in the driver coupled with another kernel failure to evict space.

The 'Fail to clip video to any crtc!' is an interesting oddity. But that looks to be just an overzealous debug message, as the event is expected for a number of circumstances.

[Chris Wilson (ickle)]

Timo, this doesn't affect raring but still affects LTS, so how do you want to procede?

[Chris Wilson (ickle)]

Fixed in raring.