Re: [PATCH] perf daemon: Avoid msan warnings on send_cmd

From: Arnaldo Carvalho de Melo
Date: Tue Sep 21 2021 - 15:26:04 EST


Em Tue, Sep 21, 2021 at 10:45:45AM -0700, Ian Rogers escreveu:
> On Wed, Jun 16, 2021 at 10:55 PM Ian Rogers <irogers@xxxxxxxxxx> wrote:
>
> > As a full union is always sent, ensure all bytes of the union are
> > initialized with memset to avoid msan warnings of use of uninitialized
> > memory.
> >
> > An example warning from the daemon test:
> >
> > Uninitialized bytes in __interceptor_write at offset 71 inside
> > [0x7ffd98da6280, 72)
> > ==11602==WARNING: MemorySanitizer: use-of-uninitialized-value
> > #0 0x5597edccdbe4 in ion tools/lib/perf/lib.c:18:6
> > #1 0x5597edccdbe4 in writen tools/lib/perf/lib.c:47:9
> > #2 0x5597ed221d30 in send_cmd tools/perf/builtin-daemon.c:1376:22
> > #3 0x5597ed21b48c in cmd_daemon tools/perf/builtin-daemon.c
> > #4 0x5597ed1d6b67 in run_builtin tools/perf/perf.c:313:11
> > #5 0x5597ed1d6036 in handle_internal_command tools/perf/perf.c:365:8
> > #6 0x5597ed1d6036 in run_argv tools/perf/perf.c:409:2
> > #7 0x5597ed1d6036 in main tools/perf/perf.c:539:3
> >
> > SUMMARY: MemorySanitizer: use-of-uninitialized-value
> > tools/lib/perf/lib.c:18:6 in ion
> > Exiting
> >
> > Signed-off-by: Ian Rogers <irogers@xxxxxxxxxx>
> >
>
> This one appears to still be outstanding. Ping.

Thanks, applied.

- Arnaldo