https://bugs.freedesktop.org/show_bug.cgi?id=101229
--- Comment #15 from Michel Dänzer michel@daenzer.net --- (In reply to Paul from comment #0)
Has affected mesa 12 and kernel 4.8 onwards.
BTW, Paul, does this mean that the problem doesn't occur if you use Mesa < 12 or kernel < 4.8? If so, can you bisect Mesa or the kernel?