052072f69f
Intel Flexible Return and Event Delivery (FRED) adds instructions ERETS (return to supervisor) and ERETU (return to user). Intel PT instruction decoder needs to know about these instructions because they are branch instructions. Similar to IRET instructions, when the decoder encounters one of these instructions it will match it to a TIP (target instruction pointer) packet that informs what the branch destination is. The existing "x86 instruction decoder - new instructions" test can be used to test the result e.g. $ perf test -v ins |& grep eret Decoded ok: f2 0f 01 ca erets Decoded ok: f3 0f 01 ca eretu Signed-off-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lore.kernel.org/r/20230320183517.15099-2-adrian.hunter@intel.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>