Thanks, Chris!
Could you also guide me to some instructions how to install these commits?
Sorry, but I haven't dared tinkering with my system at that level yet, but
having no alternatives, I may have to do it. My system is barely usable
right now.
Thanks for your patience!

On Mon, Mar 11, 2013 at 10:52 PM, Chris Wilson <email address hidden>wrote:

> You need:
>
> commit 7d54a904285b6e780291b91a518267bec5591913
> Author: Chris Wilson <email address hidden>
> Date:   Fri Aug 10 10:18:10 2012 +0100
>
>     drm/i915: Apply post-sync write for pipe control invalidates
>
> and
>
> commit 3ac7831314eba873d60b58718123c503f6961337
> Author: Jesse Barnes <email address hidden>
> Date:   Thu Oct 25 12:15:47 2012 -0700
>
>     drm/i915: PIPE_CONTROL TLB invalidate requires CS stall
>
> which are neither marked for stable, and available in v3.6 and v3.8
> respectively i.e. raring.
>
> --
> You received this bug notification because you are subscribed to the bug
> report.
> https://bugs.launchpad.net/bugs/1153587
>
> Title:
>   [sandybridge-m-gt2+ mesa] GPU lockup  IPEHR: 0x445c4000 IPEHR:
>   0x01000000
>
> Status in “xserver-xorg-video-intel” package in Ubuntu:
>   Fix Released
>
> Bug description:
>    I have been having random hangups for more than a year now, but only
>   since the beginning of last week, I have been getting the GPU hang-up
>   error messages, with or without system hang-ups. This one coincided
>   with one of the complete lock-ups, that could only be resolved by Alt
>   +SysRq-REISUB. I will now try the approach proposed in Comment #81,
>   hoping for the best. I hope that I am not seeing two different issues
>   here. The GPU hang-up error message has been reoccurring without
>   obvious hang-ups in the past few days, while my complete hang-ups have
>   been happening randomly, sometimes with the possibility to reboot as
>   outlined above, sometimes without (only the power button would do) and
>   sometimes the computer turned itself off without any interaction from
>   my side, and without leaving any trace of a crash in the log files...
>
>   ProblemType: Crash
>   DistroRelease: Ubuntu 12.10
>   Package: xserver-xorg-video-intel 2:2.20.9-0ubuntu2
>   ProcVersionSignature: Ubuntu 3.5.0-26.40-generic 3.5.7.6
>   Uname: Linux 3.5.0-26-generic x86_64
>   ApportVersion: 2.6.1-0ubuntu10
>   Architecture: amd64
>   Chipset: sandybridge-m-gt2+
>   Date: Mon Mar 11 14:03:28 2013
>   DistroCodename: quantal
>   DistroVariant: ubuntu
>   DuplicateSignature: [sandybridge-m-gt2+] GPU lockup  IPEHR: 0x445c4000
> IPEHR: 0x01000000 Ubuntu 12.10
>   ExecutablePath: /usr/share/apport/apport-gpu-error-intel.py
>   GpuHangFrequency: Several times a week
>   InstallationDate: Installed on 2011-06-28 (621 days ago)
>   InstallationMedia: Ubuntu 11.04 "Natty Narwhal" - Release amd64
> (20110427)
>   InterpreterPath: /usr/bin/python3.2mu
>   MachineType: Dell Inc. Latitude E6320
>   MarkForUpload: True
>   ProcCmdline: /usr/bin/python3 /usr/share/apport/apport-gpu-error-intel.py
>   ProcEnviron:
>
>   ProcKernelCmdLine: BOOT_IMAGE=/vmlinuz-3.5.0-26-generic
> root=UUID=5083e04c-1bad-44bf-a241-c839914a697a ro
> crashkernel=384M-2G:64M,2G-:128M quiet splash i915.semaphores=0
>   RelatedPackageVersions:
>    xserver-xorg             1:7.7+1ubuntu4
>    libdrm2                  2.4.39-0ubuntu1
>    xserver-xorg-video-intel 2:2.20.9-0ubuntu2
>   SourcePackage: xserver-xorg-video-intel
>   Title: [sandybridge-m-gt2+] GPU lockup  IPEHR: 0x445c4000 IPEHR:
> 0x01000000
>   UdevDb: Error: [Errno 2] No such file or directory: 'udevadm'
>   UpgradeStatus: Upgraded to quantal on 2012-10-27 (135 days ago)
>   UserGroups:
>
>   dmi.bios.date: 08/15/2012
>   dmi.bios.vendor: Dell Inc.
>   dmi.bios.version: A15
>   dmi.board.name: 087HK7
>   dmi.board.vendor: Dell Inc.
>   dmi.board.version: A00
>   dmi.chassis.type: 9
>   dmi.chassis.vendor: Dell Inc.
>   dmi.modalias:
> dmi:bvnDellInc.:bvrA15:bd08/15/2012:svnDellInc.:pnLatitudeE6320:pvr01:rvnDellInc.:rn087HK7:rvrA00:cvnDellInc.:ct9:cvr:
>   dmi.product.name: Latitude E6320
>   dmi.product.version: 01
>   dmi.sys.vendor: Dell Inc.
>
> To manage notifications about this bug go to:
>
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>