https://bugs.freedesktop.org/show_bug.cgi?id=60802
--- Comment #9 from Jakob Nixdorf flocke@shadowice.org --- I got similar looking corruptions in Counter Strike: Source and Trine 2 (via Steam) since my update from kernel 3.7.9 to 3.8.0 this morning (Arch Linux x86_64, newest mesa from git).
When I get back from the university I will check if I can confirm your commit as the culprit.