Trying out the "x86, AMD: Correct F15h IC aliasing issue" patch by AMD's Borislav Petkov from a Linux 3.1 (post RC10, Git) and testing with the unalias_va_addr=(32|64|off) options.
Compare your own system(s) to this result file with the Phoronix Test Suite by running the command: phoronix-test-suite benchmark 1110200-AR-BULLDOZER41