Comment 6 for bug 456814

I'm still have the issue using

apt-cache policy xserver-xorg
xserver-xorg:
  Installed: 1:7.4+3ubuntu7
  Candidate: 1:7.4+3ubuntu7
  Version table:
 *** 1:7.4+3ubuntu7 0
        500 http://ch.archive.ubuntu.com karmic/main Packages
        100 /var/lib/dpkg/status

It's now worst because I'm now unable to login with GDM. When I enter my password my session starts to load but the screen goes black with small green vertical lines and I switch temporarily to the console (Alt-F1) and see those errors :

[ 57.477288] mtrr: base(0x44000000) is not aligned on a size(0x3aa000) boundary
[ 57.631701] [drm] Using v1.4 init.
[ 60.812018] [drm:drm_reclaim_locked_buffers] *ERROR* reclaim_buffers_locked() deadlock. Please rework this
[ 60.812027] driver to use reclaim_buffers_idlelocked() instead.
[ 60.812032] I will go on reclaiming the buffers anyway.
[ 94.560032] [drm:i810_wait_ring] *ERROR* space: 65520 wanted 65528
[ 94.560101] [drm:i810_wait_ring] *ERROR* lockup