Comment # 17 on bug 64201 from Aaron Watry

I can at least confirm that the lock-ups also happen on a CEDAR (HD 5400) with
the 3.9.0 kernel and latest drm/llvm/mesa master.  This machine at least
doesn't hard lock (GPU resets after 10 seconds...), so I'll attach the results
of:

R600_DEBUG=trace_cs,nodma bfgminer -v1