9 Year Old Mesa Bug Fixed, Addresses Stability With RadeonSI Gallium3D

A nine-year-old Mesa bug has now been squashed by Marek Olšák. This Mesa bug ended up affecting the RadeonSI driver and causing stability issues, which has now been addressed and should help open-source AMD Linux gamers run titles like Team Fortress 2 and Batman Arkham: Origins (Wine).

This Mesa commit looks rather small, but it caused big problems and led to an unstable experience for RadeonSI users with some games.

One of the affected games was Team Fortress 2 for RadeonSI, which has this bug report dating back nearly one year. In there, AMD's Michel Dänzer commented, "the fundamental problem caught by Marek (good catch!) was there for almost 9 years. It just might not have had quite as severe consequences with other drivers." There's also been this Valve Software bug report among other RadeonSI stability issue reports that can be closed thanks to this fix. The fix is currently in 13.1-dev Git but should be back-ported to Mesa 13.0 too while Mesa 12.0 isn't expected to see any more point releases.