https://bugs.freedesktop.org/show_bug.cgi?id=35312
--- Comment #4 from Francis Whittle FJ.Whittle@gmail.com 2011-04-16 00:08:05 PDT --- Patch is strictly a work-around and a bloody hack (dripping even). Indicates there's something should be happening in the driver code that isn't. "Fixes" was a bad word choice.
Anyway, I can confirm this bug on RS880 (Radeon HD 4200).