From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756685Ab0IRTOy (ORCPT ); Sat, 18 Sep 2010 15:14:54 -0400 Received: from kroah.org ([198.145.64.141]:43209 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755943Ab0IRTOt (ORCPT ); Sat, 18 Sep 2010 15:14:49 -0400 X-Mailbox-Line: From gregkh@clark.site Sat Sep 18 12:12:58 2010 Message-Id: <20100918191258.551425236@clark.site> User-Agent: quilt/0.48-11.2 Date: Sat, 18 Sep 2010 12:11:53 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Lin Ming , Cyrill Gorcunov , Frederic Weisbecker , Peter Zijlstra , Ingo Molnar Subject: [015/129] perf, x86, Pentium4: Clear the P4_CCCR_FORCE_OVF flag In-Reply-To: <20100918191317.GA11386@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.35-stable review patch. If anyone has any objections, please let us know. ------------------ From: Lin Ming commit 8d330919927ea31fa083b5a80084dc991da813a0 upstream. If on Pentium4 CPUs the FORCE_OVF flag is set then an NMI happens on every event, which can generate a flood of NMIs. Clear it. Reported-by: Vince Weaver Signed-off-by: Lin Ming Signed-off-by: Cyrill Gorcunov Cc: Frederic Weisbecker Cc: Peter Zijlstra Signed-off-by: Ingo Molnar Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/cpu/perf_event_p4.c | 2 ++ 1 file changed, 2 insertions(+) --- a/arch/x86/kernel/cpu/perf_event_p4.c +++ b/arch/x86/kernel/cpu/perf_event_p4.c @@ -457,6 +457,8 @@ static int p4_hw_config(struct perf_even event->hw.config |= event->attr.config & (p4_config_pack_escr(P4_ESCR_MASK_HT) | p4_config_pack_cccr(P4_CCCR_MASK_HT)); + + event->hw.config &= ~P4_CCCR_FORCE_OVF; } rc = x86_setup_perfctr(event);