constant lock wierd signs instead of letter

[Laurynas Riliskis]

after last weeks updates my lenovo x201s laptop have started to lock to the extend that I need to take out batteries... moreover, the text in browser or e-mail can get very weird and unreadable, like some kind of other encoding.
also these crash reports are detected but the reporter crashes every time it tries to collect the data, so it goes in evil circles...

Description: Ubuntu 12.10
Release: 12.10

ProblemType: Bug
DistroRelease: Ubuntu 12.10
Package: xorg 1:7.7+1ubuntu4
ProcVersionSignature: Ubuntu 3.5.0-26.40-generic 3.5.7.6
Uname: Linux 3.5.0-26-generic x86_64
.tmp.unity.support.test.0:

ApportVersion: 2.6.1-0ubuntu10
Architecture: amd64
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: Mon Mar 4 22:47:08 2013
DistUpgraded: 2012-10-25 20:32:36,001 DEBUG enabling apt cron job
DistroCodename: quantal
DistroVariant: ubuntu
ExtraDebuggingInterest: Yes, including running git bisection searches
GraphicsCard:
 Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller [8086:0126] (rev 09) (prog-if 00 [VGA controller])
   Subsystem: Lenovo Device [17aa:21da]
InstallationDate: Installed on 2012-04-14 (324 days ago)
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120413)
MachineType: LENOVO 42914BG
MarkForUpload: True
ProcKernelCmdLine: BOOT_IMAGE=/boot/vmlinuz-3.5.0-26-generic root=UUID=5d0e4579-0e9d-4238-948b-865793d441a7 ro quiet splash xbmc=autostart,nodiskmount loglevel=0 vt.handoff=7
SourcePackage: xorg
UpgradeStatus: Upgraded to quantal on 2012-10-25 (130 days ago)
dmi.bios.date: 12/01/2011
dmi.bios.vendor: LENOVO
dmi.bios.version: 8DET56WW (1.26 )
dmi.board.asset.tag: Not Available
dmi.board.name: 42914BG
dmi.board.vendor: LENOVO
dmi.board.version: Not Available
dmi.chassis.asset.tag: No Asset Information
dmi.chassis.type: 10
dmi.chassis.vendor: LENOVO
dmi.chassis.version: Not Available
dmi.modalias: dmi:bvnLENOVO:bvr8DET56WW(1.26):bd12/01/2011:svnLENOVO:pn42914BG:pvrThinkPadX220:rvnLENOVO:rn42914BG:rvrNotAvailable:cvnLENOVO:ct10:cvrNotAvailable:
dmi.product.name: 42914BG
dmi.product.version: ThinkPad X220
dmi.sys.vendor: LENOVO
version.compiz: compiz 1:0.9.8.6-0ubuntu1
version.ia32-libs: ia32-libs N/A
version.libdrm2: libdrm2 2.4.39-0ubuntu1
version.libgl1-mesa-dri: libgl1-mesa-dri 9.0.2-0ubuntu0.1
version.libgl1-mesa-dri-experimental: libgl1-mesa-dri-experimental N/A
version.libgl1-mesa-glx: libgl1-mesa-glx 9.0.2-0ubuntu0.1
version.xserver-xorg-core: xserver-xorg-core 2:1.13.0-0ubuntu6.1
version.xserver-xorg-input-evdev: xserver-xorg-input-evdev 1:2.7.3-0ubuntu2
version.xserver-xorg-video-ati: xserver-xorg-video-ati 1:6.99.99~git20120913.8637f772-0ubuntu1
version.xserver-xorg-video-intel: xserver-xorg-video-intel 2:2.20.9-0ubuntu2
version.xserver-xorg-video-nouveau: xserver-xorg-video-nouveau 1:1.0.2-0ubuntu3

[Timo Aaltonen (tjaalton)]

try an earlier kernel than -26 which you seem to have.

[Massimo Dal Zotto (dz)]

This bugs happens continuously with all kernels AFTER linux-image-3.5.0-24-generic (installed automatically by dist-upgrade):

- linux-image-3.5.0-25-generic 3.5.0-25.39
- linux-image-3.5.0-26-generic 3.5.0-26.40
- linux-image-3.5.0-26-generic 3.5.0-26.42

The bug disappears if I reboot the system with linux-image-3.5.0-24-generic (3.5.0-24.37) so I assume it was introduced by some change in linux-image-3.5.0-25-generic.

The bug happens in various contexts but is very often triggered by switching firefox to a tab already opened on the url http://girovagandoinmontagna.com/forums/

The symptoms are usually:

- system freezes for several seconds then resumes
- garbled fonts or missing text in the above firefox page. Other urls seem to display better.
- sometimes apport-gtk loops forever while collecting bug information. Sometimes it works.

The following messages appear in the kernel log (dmesg):

[ 230.894186] [drm:i915_hangcheck_hung] *ERROR* Hangcheck timer elapsed... GPU hung
[ 230.894190] [drm] capturing error event; look for more information in /debug/dri/0/i915_error_state
[ 230.897745] [drm] Enabling RC6 states: RC6 on, RC6p off, RC6pp off

[Chris Wilson (ickle)]

TLB invalidate bug; always present just a timing change in v3.5 to trigger one presumes.

[Chris Wilson (ickle)]

And fixed in raring.