From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754021AbbLCXe5 (ORCPT ); Thu, 3 Dec 2015 18:34:57 -0500 Received: from out4-smtp.messagingengine.com ([66.111.4.28]:36959 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753899AbbLCXe4 (ORCPT ); Thu, 3 Dec 2015 18:34:56 -0500 X-Sasl-enc: XnOG+g0bJKzHE6SSCgmIPFxBvxYPqYSwuHeP1gJyuWjt 1449185694 Date: Thu, 3 Dec 2015 15:34:53 -0800 From: Greg KH To: Ashok Raj Cc: linux-kernel@vger.kernel.org, stable@vger.kernel.org, linux-edac@vger.kernel.org, Boris Petkov , Tony Luck Subject: Re: [Patch V0] x86, mce: Ensure offline CPU's don't participate in mce rendezvous process. Message-ID: <20151203233453.GA15933@kroah.com> References: <1449188170-3909-1-git-send-email-ashok.raj@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1449188170-3909-1-git-send-email-ashok.raj@intel.com> User-Agent: Mutt/1.5.24 (2015-08-30) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Thu, Dec 03, 2015 at 07:16:10PM -0500, Ashok Raj wrote: > Linux has logical cpu offline capability. That can be triggered by: > > # echo 0 > /sys/devices/system/cpu/cpuX/online > > In Intel Architecture, MCE's are broadcasted to all CPUs in the system. > > This includes the CPUs marked offline by Linux. Unless the CPU's were removed > via an ACPI notification, in which case the cpu's are removed from the > cpu_present_map. > > This patch ensures offline CPU's don't participate in MCE rendezvous, but > simply perform clearing some status bits to ensure a second MCE wont cause > automatic shutdown. > > Without the patch, mce_start will increment mce_callin, but mce_start would > wait for all online_cpus. So offline cpu's should avoid participating in the > rendezvous process. > > Reviewed-by: Tony Luck > Signed-off-by: Ashok Raj > --- > arch/x86/kernel/cpu/mcheck/mce.c | 11 ++++++++++- > 1 file changed, 10 insertions(+), 1 deletion(-) > This is not the correct way to submit patches for inclusion in the stable kernel tree. Please read Documentation/stable_kernel_rules.txt for how to do this properly.