Re: [PATCH v2 9/9] perf cs-etm: Show a warning for an unknown magic number

[Mathieu Poirier]

Hi Arnaldo,

On Wed, Sep 01, 2021 at 12:54:34PM -0300, Arnaldo Carvalho de Melo wrote:
> Em Tue, Aug 24, 2021 at 04:36:15PM +0800, Leo Yan escreveu:
> > On Fri, Aug 06, 2021 at 02:41:09PM +0100, James Clark wrote:
> > > Currently perf reports "Cannot allocate memory" which isn't very helpful
> > > for a potentially user facing issue. If we add a new magic number in
> > > the future, perf will be able to report unrecognised magic numbers.
> > > 
> > > Signed-off-by: James Clark <james.clark@xxxxxxx>
> > 
> > Reviewed-by: Leo Yan <leo.yan@xxxxxxxxxx>
> 
> Applies cleanly to my tree, test building it now, holler if there is
> something that prevents it from being merged.

Have you already merged this? 

If so than let it be.  Otherwise please hold off as I'd like to take a look,
something I intend on doing next week.

Thanks,
Mathieu

> - Arnaldo
>  
> > > ---
> > >  tools/perf/util/cs-etm.c | 5 +++++
> > >  1 file changed, 5 insertions(+)
> > > 
> > > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> > > index 788ad5a099f6..5b276bdb96a6 100644
> > > --- a/tools/perf/util/cs-etm.c
> > > +++ b/tools/perf/util/cs-etm.c
> > > @@ -2973,6 +2973,11 @@ int cs_etm__process_auxtrace_info(union perf_event *event,
> > >  
> > >  			/* ETE shares first part of metadata with ETMv4 */
> > >  			trcidr_idx = CS_ETMV4_TRCTRACEIDR;
> > > +		} else {
> > > +			ui__error("CS ETM Trace: Unrecognised magic number %#"PRIx64". File could be from a newer version of perf.\n",
> > > +				  ptr[i]);
> > > +			err = -EINVAL;
> > > +			goto err_free_metadata;
> > >  		}
> > >  
> > >  		if (!metadata[j]) {
> > > -- 
> > > 2.28.0
> > > 
> 
> -- 
> 
> - Arnaldo