Seems pretty clear at this point it's a bug in the kernel's radeon drm driver rather than the X driver.
Maybe try removing vesafb from the kernel, or try apw's purple ppa, which has a proposed fix for the vesafb conflict.
Seems pretty clear at this point it's a bug in the kernel's radeon drm driver rather than the X driver.
Maybe try removing vesafb from the kernel, or try apw's purple ppa, which has a proposed fix for the vesafb conflict.