https://bugs.freedesktop.org/show_bug.cgi?id=58667
--- Comment #13 from Thomas Rohloff v10lator@myway.de --- After going back to kernel 3.6 (3.7 not tested) I'm unable to re-trigger this bug even after doing more actions that triggered it than in every test before. So I'm pretty sure this is a kernel bug!
Is anybody able to help be bisecting the kernel? I don't even know which tree (drm-next?)