I'm also seeing frequent lockups with VI using git Mesa and LLVM (X unresponsive, radeontop showing everything at 100%). Nothing in dmesg, but that's probably just because (afaik) gpu reset is not implemented for amdgpu in 4.5. GPU: R9 380X (tonga) Mesa 11.3.0-devel (git-715e97e) LLVM r265649