From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752648AbbC1KYV (ORCPT ); Sat, 28 Mar 2015 06:24:21 -0400 Received: from mail-wi0-f170.google.com ([209.85.212.170]:38330 "EHLO mail-wi0-f170.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752054AbbC1KYT (ORCPT ); Sat, 28 Mar 2015 06:24:19 -0400 Date: Sat, 28 Mar 2015 11:24:13 +0100 From: Ingo Molnar To: Linus Torvalds Cc: linux-kernel@vger.kernel.org, Peter Zijlstra , Thomas Gleixner , Andrew Morton , Arnaldo Carvalho de Melo , Jiri Olsa Subject: [GIT PULL] perf fix Message-ID: <20150328102413.GA12717@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline User-Agent: Mutt/1.5.23 (2014-03-12) 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 # HEAD: d525211f9d1be8b523ec7633f080f2116f5ea536 perf: Fix irq_work 'tail' recursion A perf kernel side fix for a fuzzer triggered lockup. Thanks, Ingo ------------------> Peter Zijlstra (1): perf: Fix irq_work 'tail' recursion kernel/events/core.c | 10 ++++++++++ 1 file changed, 10 insertions(+) diff --git a/kernel/events/core.c b/kernel/events/core.c index 453ef61311d4..2fabc0627165 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -4574,6 +4574,13 @@ static void perf_pending_event(struct irq_work *entry) { struct perf_event *event = container_of(entry, struct perf_event, pending); + int rctx; + + rctx = perf_swevent_get_recursion_context(); + /* + * If we 'fail' here, that's OK, it means recursion is already disabled + * and we won't recurse 'further'. + */ if (event->pending_disable) { event->pending_disable = 0; @@ -4584,6 +4591,9 @@ static void perf_pending_event(struct irq_work *entry) event->pending_wakeup = 0; perf_event_wakeup(event); } + + if (rctx >= 0) + perf_swevent_put_recursion_context(rctx); } /*