From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756778AbaGIXBN (ORCPT ); Wed, 9 Jul 2014 19:01:13 -0400 Received: from mail-ob0-f171.google.com ([209.85.214.171]:51698 "EHLO mail-ob0-f171.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754457AbaGIXBM (ORCPT ); Wed, 9 Jul 2014 19:01:12 -0400 MIME-Version: 1.0 In-Reply-To: <3908561D78D1C84285E8C5FCA982C28F328574D1@ORSMSX114.amr.corp.intel.com> References: <1404925766-32253-1-git-send-email-hskinnemoen@google.com> <1404925766-32253-7-git-send-email-hskinnemoen@google.com> <3908561D78D1C84285E8C5FCA982C28F328574D1@ORSMSX114.amr.corp.intel.com> Date: Wed, 9 Jul 2014 16:01:12 -0700 Message-ID: Subject: Re: [PATCH 6/6] x86-mce: ensure the MCP timer is not already set in the mce_timer_fn. From: Havard Skinnemoen To: "Luck, Tony" Cc: Borislav Petkov , "linux-kernel@vger.kernel.org" , Ewout van Bekkum Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Jul 9, 2014 at 2:04 PM, Luck, Tony wrote: > + /* Ensure a CMCI interrupt can't preempt this. */ > + local_irq_save(flags); > if (mce_available(__this_cpu_ptr(&cpu_info))) { > machine_check_poll(MCP_TIMESTAMP, > &__get_cpu_var(mce_poll_banks)); > > Does this remove the problem that you fixed in part4? If a CMCI can > no longer interrupt a poll ... do we really need the locks you added? It's possible this fixes part of the problem. But I still think there's a race between multiple CPUs polling shared banks. Havard