I also have a Sapphire 380X with Linux 4.5 and powerplay enabled. With latest git mesa glxinfo completely freezes the system. I have made a git bisect and it shows this commit: https://cgit.freedesktop.org/mesa/mesa/commit/?id=ec74deeb2466689a0eca52f290d5f9e44af6a97b radeonsi: set amdgpu metadata before exporting a texture I don't know if this has something to do with this bug but after reverting it i get no more freezes.