4.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: Adrian Hunter <adrian.hunter@xxxxxxxxx> commit 076333870c2f5bdd9b6d31e7ca1909cf0c84cbfa upstream. When TSC is not available, "timeless" decoding is used but a divide by zero occurs if perf_time_to_tsc() is called. Ensure the divisor is not zero. Signed-off-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: Jiri Olsa <jolsa@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx # v4.9+ Link: https://lkml.kernel.org/n/tip-1i4j0wqoc8vlbkcizqqxpsf4@xxxxxxxxxxxxxx Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- tools/perf/util/intel-pt.c | 2 ++ 1 file changed, 2 insertions(+) --- a/tools/perf/util/intel-pt.c +++ b/tools/perf/util/intel-pt.c @@ -2507,6 +2507,8 @@ int intel_pt_process_auxtrace_info(union } pt->timeless_decoding = intel_pt_timeless_decoding(pt); + if (pt->timeless_decoding && !pt->tc.time_mult) + pt->tc.time_mult = 1; pt->have_tsc = intel_pt_have_tsc(pt); pt->sampling_mode = false; pt->est_tsc = !pt->timeless_decoding;
