From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751910Ab2G0KQL (ORCPT ); Fri, 27 Jul 2012 06:16:11 -0400 Received: from cantor2.suse.de ([195.135.220.15]:57824 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751643Ab2G0KQI (ORCPT ); Fri, 27 Jul 2012 06:16:08 -0400 Message-ID: <50126A64.9040206@suse.de> Date: Fri, 27 Jul 2012 12:16:04 +0200 From: Hannes Reinecke User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:13.0) Gecko/20120601 Thunderbird/13.0 MIME-Version: 1.0 To: James Bottomley Cc: Christoph Hellwig , Paolo Bonzini , linux-kernel@vger.kernel.org, linux-scsi@vger.kernel.org Subject: Re: [PATCH] sd: do not set changed flag on all unit attention conditions References: <1342454772-9018-1-git-send-email-pbonzini@redhat.com> <1342455503.3176.42.camel@dabdike.int.hansenpartnership.com> <50044D56.6000400@redhat.com> <1342511100.3039.9.camel@dabdike.int.hansenpartnership.com> <50052390.7030908@redhat.com> <1342514444.3039.23.camel@dabdike.int.hansenpartnership.com> <5005285E.8060706@redhat.com> <1342516317.3039.35.camel@dabdike.int.hansenpartnership.com> <20120717163612.GA15995@infradead.org> <1342562390.3039.100.camel@dabdike.int.hansenpartnership.com> In-Reply-To: <1342562390.3039.100.camel@dabdike.int.hansenpartnership.com> X-Enigmail-Version: 1.4.2 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 07/17/2012 11:59 PM, James Bottomley wrote: > On Tue, 2012-07-17 at 12:36 -0400, Christoph Hellwig wrote: >> On Tue, Jul 17, 2012 at 10:11:57AM +0100, James Bottomley wrote: >>> There's no such thing in the market today as a removable disk that's >>> resizeable. Removable disks are for things like backup cartridges and >>> ageing jazz drives. Worse: most removeable devices today are USB card >>> readers whose standards compliance varies from iffy to non existent. >>> Resizeable disks are currently the province of storage arrays. >> >> The virtual disks exported by aacraid are both marked removable and >> can be resized. > > So what are properties of these things? ... or is this just an instance > of a RAID manufacturer hacking around a problem by adding a removable > flag? > Presumably. The general intention is to automatically catch any disk resizing. As the SCSI stack (used to) ignore these things that was their way of working around it. Curiously, though; the aacraid driver is the only one doing this, plus the process is quite involved (using a proprietary application for doing so etc). None of the FC driver do this, despite the fact that resizing a disk is even easier here. I even tried to remove that line once, but then got told off by then Adaptec that I would break their apps. Since then there's a patch in the SLES kernel for adding a module option switching off this behaviour. We should ask Adaptec/PMC-Sierra here. Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage hare@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg)