Bug#774899: libdrm-intel1: 855GM: Failed to submit batch buffer, expect rendering corruption: No space left on device

[Matthias Großmann <grossmms@googlemail.com>]

Update on this bug: My first assumption that
drm_intel_gem_check_aperture_space() causes this problem is probably
wrong. As it turned out, this function fails a lot more often than I
see the "failed to submit batch buffer" message in Xorg.0.log - in
general without any noticeable impact.

After enabling some more debug output, I am now seeing the error
message

Execbuffer fails to pin. Estimate: 234897408. Actual: 67125248. Available: 
130940928

so I guess that the DRM_IOCTL_I915_GEM_EXECBUFFER2 ioctl in do_exec2()
causes the failure.

LibreOffice's print dialog can (sometimes) also trigger this bug.