From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932099Ab0ERRRw (ORCPT ); Tue, 18 May 2010 13:17:52 -0400 Received: from hera.kernel.org ([140.211.167.34]:60759 "EHLO hera.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758492Ab0ERRRp (ORCPT ); Tue, 18 May 2010 13:17:45 -0400 Date: Tue, 18 May 2010 17:16:01 GMT From: tip-bot for Stephane Eranian Cc: linux-kernel@vger.kernel.org, acme@redhat.com, paulus@samba.org, eranian@google.com, hpa@zytor.com, mingo@redhat.com, a.p.zijlstra@chello.nl, efault@gmx.de, fweisbec@gmail.com, tglx@linutronix.de, mingo@elte.hu Reply-To: mingo@redhat.com, hpa@zytor.com, eranian@google.com, paulus@samba.org, acme@redhat.com, linux-kernel@vger.kernel.org, fweisbec@gmail.com, a.p.zijlstra@chello.nl, efault@gmx.de, tglx@linutronix.de, mingo@elte.hu In-Reply-To: <4bf13674.014fd80a.6c82.ffffb20c@mx.google.com> References: <4bf13674.014fd80a.6c82.ffffb20c@mx.google.com> To: linux-tip-commits@vger.kernel.org Subject: [tip:perf/core] perf: Fix errors path in perf_output_begin() Message-ID: Git-Commit-ID: 00d1d0b095ba4e5c0958cb228b2a9c445d4a339d X-Mailer: tip-git-log-daemon MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Disposition: inline X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.2.3 (hera.kernel.org [127.0.0.1]); Tue, 18 May 2010 17:16:02 +0000 (UTC) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Commit-ID: 00d1d0b095ba4e5c0958cb228b2a9c445d4a339d Gitweb: http://git.kernel.org/tip/00d1d0b095ba4e5c0958cb228b2a9c445d4a339d Author: Stephane Eranian AuthorDate: Mon, 17 May 2010 12:46:01 +0200 Committer: Ingo Molnar CommitDate: Tue, 18 May 2010 18:35:47 +0200 perf: Fix errors path in perf_output_begin() In case the sampling buffer has no "payload" pages, nr_pages is 0. The problem is that the error path in perf_output_begin() skips to a label which assumes perf_output_lock() has been issued which is not the case. That triggers a WARN_ON() in perf_output_unlock(). This patch fixes the problem by skipping perf_output_unlock() in case data->nr_pages is 0. Signed-off-by: Stephane Eranian Signed-off-by: Peter Zijlstra Cc: Mike Galbraith Cc: Paul Mackerras Cc: Arnaldo Carvalho de Melo Cc: Frederic Weisbecker LKML-Reference: <4bf13674.014fd80a.6c82.ffffb20c@mx.google.com> Signed-off-by: Ingo Molnar --- kernel/perf_event.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/perf_event.c b/kernel/perf_event.c index 17ac47f..8d61d29 100644 --- a/kernel/perf_event.c +++ b/kernel/perf_event.c @@ -3036,7 +3036,7 @@ int perf_output_begin(struct perf_output_handle *handle, handle->sample = sample; if (!data->nr_pages) - goto fail; + goto out; have_lost = atomic_read(&data->lost); if (have_lost)