Re: [PATCH v3] perf report: Skip unsupported new event types

[Namhyung Kim <namhyung@kernel.org>]

On Fri, Apr 11, 2025 at 10:45:21AM -0700, Chun-Tse Shao wrote:
> `perf report` currently halts with an error when encountering
> unsupported new event types (`event.type >= PERF_RECORD_HEADER_MAX`).
> This patch modifies the behavior to skip these samples and continue
> processing the remaining events. Additionally, stops reporting if the
> new event size is not 8-byte aligned.
> 
> Signed-off-by: Chun-Tse Shao <ctshao@google.com>
> Suggested-by: Arnaldo Carvalho de Melo <acme@kernel.org>
> Suggested-by: Namhyung Kim <namhyung@kernel.org>
> ---
>  tools/perf/util/session.c | 13 +++++++++++--
>  1 file changed, 11 insertions(+), 2 deletions(-)
> 
> diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c
> index 60fb9997ea0d..f55b2ac4e103 100644
> --- a/tools/perf/util/session.c
> +++ b/tools/perf/util/session.c
> @@ -1639,8 +1639,17 @@ static s64 perf_session__process_event(struct perf_session *session,
>  	if (session->header.needs_swap)
>  		event_swap(event, evlist__sample_id_all(evlist));
>  
> -	if (event->header.type >= PERF_RECORD_HEADER_MAX)
> -		return -EINVAL;
> +	if (event->header.type >= PERF_RECORD_HEADER_MAX) {
> +		/* perf should not support unaligned event, stop here. */
> +		if (event->header.size % sizeof(u64))
> +			return -EINVAL;
> +
> +		/* This perf is outdated and does not support the latest event type. */
> +		ui__warning("Unsupported type %u, please considering update perf.\n",
> +			    event->header.type);
> +		/* Skip unsupported/unaligned event by returning its size. */

This comment also needs update.  Other than that looks good to me.

Thanks,
Namhyung

> +		return event->header.size;
> +	}
>  
>  	events_stats__inc(&evlist->stats, event->header.type);
>  
> -- 
> 2.49.0.604.gff1f9ca942-goog
>