Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934193Ab2EXTRf (ORCPT ); Thu, 24 May 2012 15:17:35 -0400 Received: from acsinet15.oracle.com ([141.146.126.227]:48718 "EHLO acsinet15.oracle.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S965465Ab2EXTRY (ORCPT ); Thu, 24 May 2012 15:17:24 -0400 Date: Thu, 24 May 2012 15:10:39 -0400 From: Konrad Rzeszutek Wilk To: "Liu, Jinsong" Cc: Borislav Petkov , "linux-kernel@vger.kernel.org" , "Luck, Tony" , "xen-devel@lists.xensource.com" Subject: Re: [Xen-devel] [PATCH 1/3] xen/mce: Add mcelog support for Xen platform (v2) Message-ID: <20120524191039.GB28338@phenom.dumpdata.com> References: <20120522092354.GB18578@aftab.osrc.amd.com> <20120524103023.GA27063@aftab.osrc.amd.com> <20120524162605.GK27063@aftab.osrc.amd.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.21 (2010-09-15) X-Source-IP: acsinet22.oracle.com [141.146.126.238] Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2188 Lines: 50 > >> The reason is, if we do so, it would be covered by native > >> misc_register(&mce_chrdev_device) later when native kernel init (xen > >> init first and then start native kernel). > >> Under such case, if linux running under xen platform, /dev/mcelog > >> point to vcpu, that's pointless since it cannot get any mcelog from > >> physical cpu (which owned by xen). > >> > >> Yes, we can use another misc device like /dev/xen-mcelog, w/ another > >> device minor like 226, but that's not good for userspace mcelog > >> tools. As far as I know, Novell mcelog use unified /dev/mcelog > >> interface for linux running under either bare metal or xen platform. > > > > Maybe create a symlink in /dev/mcelog pointing to /dev/xen-mcelog? > > > > That should solve it. > > Kernel has created a file /dev/mcelog no matter running at native or xen platform. > If xen try to mask kernel creating /dev/mcelog, that would be harmful to native kernel. Huh? The Xen code won't run under native kernel so how will it mask it? > > > > >> This patch just do redirection at xen code path, and that would not > >> hurt anything to native kernel. > > > > My concern is that if we remove /dev/mcelog one day, xen people will > > cry. Hehe. The goal here is to serve the distros so to say. So if the distros stop using /dev/mcelog and the /dev/mcelog goes away we won't cry b/c well, the user of it has gone away! So the moment you remove that, pls CC us so we can remove it too and retool to use the MCElogv2. > > Don't worry :) > Xen people would handle that case (that's not trouble for xen), just notify us is enough. > If kernel really remove /dev/mcelog some day, xen just need simply add 1 line misc_register(&xen_mce_chrdev_device), since currently all other code are xen-self-contained. Well, I will delete it. My customer is distro (Fedora, Debian, Oracle and SuSE)- and if the distro is not using it there is not point of keeping it. -- 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/