Re: [PATCH 2/2] perf: cs-etm: Fix corrupt inject files when only last branch option is enabled

From: Arnaldo Carvalho de Melo <acme@kernel.org>
To: Leo Yan <leo.yan@linaro.org>
Cc: James Clark <james.clark@arm.com>,
	linux-perf-users@vger.kernel.org, mathieu.poirier@linaro.org,
	coresight@lists.linaro.org, Mike Leach <mike.leach@linaro.org>,
	John Garry <john.garry@huawei.com>, Will Deacon <will@kernel.org>,
	Mark Rutland <mark.rutland@arm.com>,
	Alexander Shishkin <alexander.shishkin@linux.intel.com>,
	Jiri Olsa <jolsa@redhat.com>, Namhyung Kim <namhyung@kernel.org>,
	linux-arm-kernel@lists.infradead.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] perf: cs-etm: Fix corrupt inject files when only last branch option is enabled
Date: Tue, 15 Feb 2022 12:07:18 -0300	[thread overview]
Message-ID: <YgvBpvYzAMCGSECj@kernel.org> (raw)
In-Reply-To: <20220211160516.GD475776@leoy-ThinkPad-X240s>

Em Sat, Feb 12, 2022 at 12:05:16AM +0800, Leo Yan escreveu:
> On Thu, Feb 10, 2022 at 08:06:20PM +0000, James Clark wrote:
> > Perf inject with Coresight data generates files that cannot be opened
> > when only the last branch option is specified:
> > 
> >   perf inject -i perf.data --itrace=l -o inject.data
> >   perf script -i inject.data
> >   0x33faa8 [0x8]: failed to process type: 9 [Bad address]
> > 
> > This is because cs_etm__synth_instruction_sample() is called even when
> > the sample type for instructions hasn't been setup. Last branch records
> > are attached to instruction samples so it doesn't make sense to generate
> > them when --itrace=i isn't specified anyway.
> > 
> > This change disables all calls of cs_etm__synth_instruction_sample()
> > unless --itrace=i is specified, resulting in a file with no samples if
> > only --itrace=l is provided, rather than a bad file.
> > 
> > Signed-off-by: James Clark <james.clark@arm.com>
> 
> Reviewed-by: Leo Yan <leo.yan@linaro.org>

Thanks, applied.

- Arnaldo

> > ---
> >  tools/perf/util/cs-etm.c | 2 ++
> >  1 file changed, 2 insertions(+)
> > 
> > diff --git a/tools/perf/util/cs-etm.c b/tools/perf/util/cs-etm.c
> > index 796a065a500e..8b95fb3c4d7b 100644
> > --- a/tools/perf/util/cs-etm.c
> > +++ b/tools/perf/util/cs-etm.c
> > @@ -1553,6 +1553,7 @@ static int cs_etm__flush(struct cs_etm_queue *etmq,
> >  		goto swap_packet;
> >  
> >  	if (etmq->etm->synth_opts.last_branch &&
> > +	    etmq->etm->synth_opts.instructions &&
> >  	    tidq->prev_packet->sample_type == CS_ETM_RANGE) {
> >  		u64 addr;
> >  
> > @@ -1610,6 +1611,7 @@ static int cs_etm__end_block(struct cs_etm_queue *etmq,
> >  	 * the trace.
> >  	 */
> >  	if (etmq->etm->synth_opts.last_branch &&
> > +	    etmq->etm->synth_opts.instructions &&
> >  	    tidq->prev_packet->sample_type == CS_ETM_RANGE) {
> >  		u64 addr;
> >  
> > -- 
> > 2.28.0
> > 

-- 

- Arnaldo