https://bugs.freedesktop.org/show_bug.cgi?id=83416
--- Comment #2 from Michel Dänzer michel@daenzer.net --- I get no lockup either, but I do see the same GPUVM protection faults:
radeon 0000:01:00.0: VM_CONTEXT1_PROTECTION_FAULT_ADDR 0x0FF00819
The FF bits make me suspect bits 32-4x of the GPUVM address are getting clobbered, maybe because of the LLVM backend generating invalid shader code.