From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from eggs.gnu.org ([2001:4830:134:3::10]:47502)
	by lists.gnu.org with esmtp (Exim 4.71)
	(envelope-from <ghammer@redhat.com>) id 1Z1yxN-0001l8-2q
	for qemu-devel@nongnu.org; Mon, 08 Jun 2015 11:27:21 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <ghammer@redhat.com>) id 1Z1yxI-0000wE-4Z
	for qemu-devel@nongnu.org; Mon, 08 Jun 2015 11:27:21 -0400
Received: from mx1.redhat.com ([209.132.183.28]:43070)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <ghammer@redhat.com>) id 1Z1yxI-0000va-0J
	for qemu-devel@nongnu.org; Mon, 08 Jun 2015 11:27:16 -0400
Received: from int-mx09.intmail.prod.int.phx2.redhat.com
	(int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22])
	by mx1.redhat.com (Postfix) with ESMTPS id ADCE119F275
	for <qemu-devel@nongnu.org>; Mon,  8 Jun 2015 15:27:15 +0000 (UTC)
Message-ID: <5575B497.9030808@redhat.com>
Date: Mon, 08 Jun 2015 18:28:23 +0300
From: Gal Hammer <ghammer@redhat.com>
MIME-Version: 1.0
References: <1430133591-6197-1-git-send-email-ghammer@redhat.com>
	<1430133591-6197-5-git-send-email-ghammer@redhat.com>
	<556F2D51.2000203@redhat.com> <55759BB8.3010604@redhat.com>
	<55759C1B.7000905@redhat.com> <55759E0A.3090102@redhat.com>
	<55759EC2.5090802@redhat.com> <20150608135854.GC19157@redhat.com>
	<20150608165951-mutt-send-email-mst@redhat.com>
	<5575B20B.9000502@redhat.com>
	<20150608171921-mutt-send-email-mst@redhat.com>
In-Reply-To: <20150608171921-mutt-send-email-mst@redhat.com>
Content-Type: text/plain; charset=windows-1252; format=flowed
Content-Transfer-Encoding: 7bit
Subject: Re: [Qemu-devel] [PATCH V15 4/5] i386: add a Virtual Machine
	Generation ID device
List-Id: <qemu-devel.nongnu.org>
List-Unsubscribe: <https://lists.nongnu.org/mailman/options/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <https://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: "Michael S. Tsirkin" <mst@redhat.com>, Paolo Bonzini <pbonzini@redhat.com>
Cc: imammedo@redhat.com, qemu-devel@nongnu.org

On 08/06/2015 18:22, Michael S. Tsirkin wrote:
> On Mon, Jun 08, 2015 at 05:17:31PM +0200, Paolo Bonzini wrote:
>>
>>
>> On 08/06/2015 17:01, Michael S. Tsirkin wrote:
>>> Are there applications that would actually use this?  For microsoft this
>>> seems to be mostly driven by ActiveDirectory needs.
>>> It seems quite possible that applications solve the problem
>>> differently on Linux.
>>
>> I'm not aware of a different solution to the problem on Linux.
>>
>> Paolo
>
> Adding it by default for everyone still seems too aggressive.
> We had a ton of pain with pvpanic exactly because of a
> similar "can't hurt" approach.
>
> I think a better approach would be to merge the code in qemu,
> merge a linux driver. Once that's available, and some apps use it,
> enabling it by default will seem more reasonable.
>

You should not enable it by default. It should be left for the 
management system to decide. QEmu by itself can't follow rules/spec on 
when to change the UUID.

     Gal.