From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756123Ab1HCX1E (ORCPT ); Wed, 3 Aug 2011 19:27:04 -0400 Received: from cantor2.suse.de ([195.135.220.15]:33555 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756107Ab1HCX04 (ORCPT ); Wed, 3 Aug 2011 19:26:56 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Wed Aug 3 15:12:48 2011 Message-Id: <20110803221248.000193604@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Wed, 03 Aug 2011 15:01:00 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org, Vince Weaver Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Ingo Molnar , Paul Mackerras , Arnaldo Carvalho de Melo , Peter Zijlstra Subject: [040/102] perf: Fix software event overflow In-Reply-To: <20110803221345.GA10346@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.0-stable review patch. If anyone has any objections, please let us know. ------------------ From: Peter Zijlstra The below patch is for -stable only, upstream has a much larger patch that contains the below hunk in commit a8b0ca17b80e92faab46ee7179ba9e99ccb61233 Vince found that under certain circumstances software event overflows go wrong and deadlock. Avoid trying to delete a timer from the timer callback. Reported-by: Vince Weaver Signed-off-by: Peter Zijlstra Signed-off-by: Greg Kroah-Hartman --- kernel/events/core.c | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -5016,11 +5016,8 @@ static int __perf_event_overflow(struct if (events && atomic_dec_and_test(&event->event_limit)) { ret = 1; event->pending_kill = POLL_HUP; - if (nmi) { - event->pending_disable = 1; - irq_work_queue(&event->pending); - } else - perf_event_disable(event); + event->pending_disable = 1; + irq_work_queue(&event->pending); } if (event->overflow_handler)