iv/linux
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

perf intel-pt: Fix divide by zero when TSC is not available

Browse Source 
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@intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: stable@vger.kernel.org # v4.9+
Link: https://lkml.kernel.org/n/tip-1i4j0wqoc8vlbkcizqqxpsf4@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Adrian Hunter 2019-03-01 12:35:36 +02:00 committed by Greg Kroah-Hartman
parent da4f86ffdb
commit 73e0b59ffb
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
tools/perf/util/intel-pt.c
View File

@ -2545,6 +2545,8 @@ int intel_pt_process_auxtrace_info(union perf_event *event,
}
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;