Character corruption with 2.6.37

[Tino Keitel <tino.keitel+xorg@tikei.de>]

Hi,

I see character corruption in X with 2.6.37, libdrm 2.4.21 and 2.4.23,
intel-xorg 2.13 and Xserver 1.7.7 (Debian Sid). In the kernel, I see
such log entries:

[drm:i915_gem_object_unbind] *ERROR* Attempting to unbind pinned buffer

Xorg.0.log looks like this:

(WW) intel(0): intel_uxa_prepare_access: bo map failed: Invalid argument
(EE) intel(0): Failed to submit batch buffer, expect rendering
corruption or even a frozen display: Invalid argument.

This happens on a Mac mini Core Duo with i945 graphics.

Any hints how to fix this? I tested some 2.6.37-rc kernels (rc3 to rc8)
without having this issue. So it might be some upgrade of another
component. I downgraded libdrm2 from 2.4.23 to 2.4.21, and restarted
the X server, but it didn't help.

Regards,
Tino