https://bugs.freedesktop.org/show_bug.cgi?id=60236
--- Comment #5 from Alex Deucher agd5f@yahoo.com --- (In reply to comment #1)
linux 3.8-rc6 3.7.4 had it also
325422c49449acdd8df1eb2ca8ed81f7696c38cc (r600g: add async for staging buffer upload v2) only takes affect on 3.8 kernels. Previous kernels didn't support the DMA rings. So if you are seeing the same issue on multiple kernels, it's either something else or you are seeing two issues. It may be the same issue as bug 58042.