Comment # 8 on bug 61533 from Alex Deucher

This is most likely a mesa issue; there are several new features in mesa that
are only enabled with a 3.8 kernel.  Can one of you use git to bisect mesa to
see what commit broke things?  bisecting is a feature of git that allows you to
easily narrow down what commit to a project caused the breakage.  You might
also try mesa from the 9.1 branch.  Also, if you are using the llvm backend in
the r600 driver, you might try disabling that.