From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753585AbdDJUQT (ORCPT ); Mon, 10 Apr 2017 16:16:19 -0400 Received: from mail-pf0-f181.google.com ([209.85.192.181]:35249 "EHLO mail-pf0-f181.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752844AbdDJUPE (ORCPT ); Mon, 10 Apr 2017 16:15:04 -0400 From: David Carrillo-Cisneros To: linux-kernel@vger.kernel.org Cc: Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Alexander Shishkin , Andi Kleen , Simon Que , Wang Nan , Jiri Olsa , He Kuang , Masami Hiramatsu , Stephane Eranian , Paul Turner , David Carrillo-Cisneros Subject: [PATCH 2/7] perf inject: copy events when reordering events in pipe mode Date: Mon, 10 Apr 2017 13:14:27 -0700 Message-Id: <20170410201432.24807-3-davidcc@google.com> X-Mailer: git-send-email 2.12.2.715.g7642488e1d-goog In-Reply-To: <20170410201432.24807-1-davidcc@google.com> References: <20170410201432.24807-1-davidcc@google.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org __perf_session__process_pipe_events reuses the same memory buffer to process all events in the pipe. When reordering is needed (e.g. -b option), events are not immediately flushed, but kept around until reordering is possible, causing memory corruption. The problem is usually observed by a "Unknown sample error" output. It can easily be reproduced by: perf record -o - noploop | perf inject -b > output Signed-off-by: David Carrillo-Cisneros --- tools/perf/util/ordered-events.c | 3 ++- tools/perf/util/session.c | 1 + 2 files changed, 3 insertions(+), 1 deletion(-) diff --git a/tools/perf/util/ordered-events.c b/tools/perf/util/ordered-events.c index fe84df1875aa..e70e935b1841 100644 --- a/tools/perf/util/ordered-events.c +++ b/tools/perf/util/ordered-events.c @@ -79,7 +79,7 @@ static union perf_event *dup_event(struct ordered_events *oe, static void free_dup_event(struct ordered_events *oe, union perf_event *event) { - if (oe->copy_on_queue) { + if (event && oe->copy_on_queue) { oe->cur_alloc_size -= event->header.size; free(event); } @@ -150,6 +150,7 @@ void ordered_events__delete(struct ordered_events *oe, struct ordered_event *eve list_move(&event->list, &oe->cache); oe->nr_events--; free_dup_event(oe, event->event); + event->event = NULL; } int ordered_events__queue(struct ordered_events *oe, union perf_event *event, diff --git a/tools/perf/util/session.c b/tools/perf/util/session.c index 24259bc2c598..a25302bc55a8 100644 --- a/tools/perf/util/session.c +++ b/tools/perf/util/session.c @@ -1656,6 +1656,7 @@ static int __perf_session__process_pipe_events(struct perf_session *session) buf = malloc(cur_size); if (!buf) return -errno; + ordered_events__set_copy_on_queue(oe, true); more: event = buf; err = readn(fd, event, sizeof(struct perf_event_header)); -- 2.12.2.715.g7642488e1d-goog