https://bugs.freedesktop.org/show_bug.cgi?id=91994

--- Comment #5 from Adam Flott adam@adamflott.com --- (In reply to Adam Flott from comment #4)

This looks to have been fixed from 4.2->4.3 xf86-video-ati 7.5->7.6 and I thank you immensely. My sanity has been restored.

That is Linux kernel 4.2->4.3