From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752134Ab1LQUzS (ORCPT ); Sat, 17 Dec 2011 15:55:18 -0500 Received: from mx3.mail.elte.hu ([157.181.1.138]:45223 "EHLO mx3.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751232Ab1LQUzP (ORCPT ); Sat, 17 Dec 2011 15:55:15 -0500 Date: Sat, 17 Dec 2011 21:53:18 +0100 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Arnaldo Carvalho de Melo , Andrew Morton , Thomas Gleixner Subject: [GIT PULL] perf fix Message-ID: <20111217205318.GA3146@elte.hu> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.21 (2010-09-15) X-ELTE-SpamScore: -2.0 X-ELTE-SpamLevel: X-ELTE-SpamCheck: no X-ELTE-SpamVersion: ELTE 2.0 X-ELTE-SpamCheck-Details: score=-2.0 required=5.9 tests=AWL,BAYES_00 autolearn=no SpamAssassin version=3.3.1 -2.0 BAYES_00 BODY: Bayes spam probability is 0 to 1% [score: 0.0000] 0.0 AWL AWL: From: address is in the auto white-list Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Linus, Please pull the latest perf-urgent-for-linus git tree from: git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip.git perf-urgent-for-linus Thanks, Ingo ------------------> Will Deacon (1): perf events: Fix ring_buffer_wakeup() brown paperbag bug kernel/events/core.c | 8 ++++++-- 1 files changed, 6 insertions(+), 2 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index d3b9df5..58690af 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -3558,9 +3558,13 @@ static void ring_buffer_wakeup(struct perf_event *event) rcu_read_lock(); rb = rcu_dereference(event->rb); - list_for_each_entry_rcu(event, &rb->event_list, rb_entry) { + if (!rb) + goto unlock; + + list_for_each_entry_rcu(event, &rb->event_list, rb_entry) wake_up_all(&event->waitq); - } + +unlock: rcu_read_unlock(); }