Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758263Ab2EYSBL (ORCPT ); Fri, 25 May 2012 14:01:11 -0400 Received: from mga14.intel.com ([143.182.124.37]:60167 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756919Ab2EYSBI convert rfc822-to-8bit (ORCPT ); Fri, 25 May 2012 14:01:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.71,315,1320652800"; d="scan'208";a="147874220" From: "Liu, Jinsong" To: Konrad Rzeszutek Wilk 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) Thread-Topic: [Xen-devel] [PATCH 1/3] xen/mce: Add mcelog support for Xen platform (v2) Thread-Index: AQHNOeHZr6jLO/PX8Ee8ZH/5SHvSCZbazB1A Date: Fri, 25 May 2012 18:01:04 +0000 Message-ID: References: <20120522092354.GB18578@aftab.osrc.amd.com> <20120524103023.GA27063@aftab.osrc.amd.com> <20120524162605.GK27063@aftab.osrc.amd.com> <20120524191039.GB28338@phenom.dumpdata.com> In-Reply-To: <20120524191039.GB28338@phenom.dumpdata.com> Accept-Language: en-US Content-Language: en-US X-MS-Has-Attach: X-MS-TNEF-Correlator: x-originating-ip: [10.239.127.40] Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 8BIT MIME-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2353 Lines: 62 Konrad Rzeszutek Wilk wrote: >>>> 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? Hmm, I mean 'xen related code' of linux kernel, e.g. drivers/xen/... >> >>> >>>> 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/