Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752223Ab3IIGVS (ORCPT ); Mon, 9 Sep 2013 02:21:18 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:35098 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751212Ab3IIGVR (ORCPT ); Mon, 9 Sep 2013 02:21:17 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.8.9 X-SHieldMailCheckerPolicyVersion: FJ-ISEC-20120718-2 Message-ID: <522D681E.1030809@jp.fujitsu.com> Date: Mon, 09 Sep 2013 15:18:06 +0900 From: HATAYAMA Daisuke User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130801 Thunderbird/17.0.8 MIME-Version: 1.0 To: Borislav Petkov CC: jingbai.ma@hp.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, ebiederm@xmission.com, akpm@linux-foundation.org, hpa@linux.intel.com, vgoyal@redhat.com Subject: Re: [PATCH 2/2] x86, apic: Disable BSP if boot cpu is AP References: <20130829092458.5476.10277.stgit@localhost6.localdomain6> <20130829092804.5476.95588.stgit@localhost6.localdomain6> <20130831052252.GC12617@x1.alien8.de> <5223F8DB.3040506@jp.fujitsu.com> <20130902071318.GA3406@x1.alien8.de> <52245D94.5050702@jp.fujitsu.com> <20130904061221.GA17791@x1.alien8.de> In-Reply-To: <20130904061221.GA17791@x1.alien8.de> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1098 Lines: 30 (2013/09/04 15:12), Borislav Petkov wrote: > On Mon, Sep 02, 2013 at 06:42:44PM +0900, HATAYAMA Daisuke wrote: >> The reason why I don't lookup BSP flag in MSR is that it's impossible. >> To read MSR of some CPU, we need to use rdmsr instruction on the CPU. >> However, in case of this issue, the BSP is halting or running in >> the kdump 1st kernel. > > Yes, and on the AP, that flag would be cleared which makes it not a BSP. > >> A whole explanation is written in the patch description. > > Those tend to get lost in git history when a bunch of whitespace jerk > offs appear ontop. So a nicely written comment in the code could be very > helpful. > > Thanks. > Yes, that's the point this patch series misses. I'll describe the explanation in Documentation/kexec/kexec.txt and point it in the comment of boot-up code. -- Thanks. HATAYAMA, Daisuke -- 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/