Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752389AbaA2IMJ (ORCPT ); Wed, 29 Jan 2014 03:12:09 -0500 Received: from david.siemens.de ([192.35.17.14]:46555 "EHLO david.siemens.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751631AbaA2ILx (ORCPT ); Wed, 29 Jan 2014 03:11:53 -0500 Message-ID: <52E8B7B0.8050803@siemens.com> Date: Wed, 29 Jan 2014 09:11:28 +0100 From: Jan Kiszka User-Agent: Mozilla/5.0 (X11; U; Linux i686 (x86_64); de; rv:1.8.1.12) Gecko/20080226 SUSE/2.0.0.12-1.1 Thunderbird/2.0.0.12 Mnenhy/0.7.5.666 MIME-Version: 1.0 To: Andi Kleen CC: Ingo Molnar , Ingo Molnar , Thomas Gleixner , "H. Peter Anvin" , Linux Kernel Mailing List Subject: Re: [PATCH] x86: Plug racy xAPIC access of CPU hotplug code References: <52E6AFFE.3030004@siemens.com> <20140127202252.GA11821@two.firstfloor.org> <52E767C2.2090807@siemens.com> <20140128115549.GA26230@gmail.com> <52E79DEA.3010408@siemens.com> <20140128211702.GB11821@two.firstfloor.org> In-Reply-To: <20140128211702.GB11821@two.firstfloor.org> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2014-01-28 22:17, Andi Kleen wrote: > Also with irq-off you of course still always have races against > the NMI-level machine check. The self-IPI triggered over NMI won't touch the high-part of the ICR and will properly wait for ICR to become free again. So we are safe. Jan -- Siemens AG, Corporate Technology, CT RTC ITP SES-DE Corporate Competence Center Embedded Linux -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/