From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:39663) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z7lzP-0002ZZ-LP for qemu-devel@nongnu.org; Wed, 24 Jun 2015 10:49:24 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1Z7lzM-0000ow-As for qemu-devel@nongnu.org; Wed, 24 Jun 2015 10:49:23 -0400 Received: from cantor2.suse.de ([195.135.220.15]:38370 helo=mx2.suse.de) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1Z7lli-0002lu-NT for qemu-devel@nongnu.org; Wed, 24 Jun 2015 10:35:14 -0400 Message-ID: <558AC021.1080403@suse.de> Date: Wed, 24 Jun 2015 16:35:13 +0200 From: =?windows-1252?Q?Andreas_F=E4rber?= MIME-Version: 1.0 References: <558951C0.3050806@suse.de> <20150623150828.GD3134@thinpad.lan.raisama.net> <20150623173048-mutt-send-email-mst@redhat.com> <20150623155832.GE3134@thinpad.lan.raisama.net> <55898637.6080804@suse.de> <20150623162555.GL30318@redhat.com> <20150623183115-mutt-send-email-mst@redhat.com> <20150623164204.GM30318@redhat.com> <20150623231818-mutt-send-email-mst@redhat.com> <20150624141651.GS3134@thinpad.lan.raisama.net> <20150624161820-mutt-send-email-mst@redhat.com> In-Reply-To: <20150624161820-mutt-send-email-mst@redhat.com> Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH 0/2] target-i386: "custom" CPU model + script to dump existing CPU models List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Michael S. Tsirkin" Cc: mimu@linux.vnet.ibm.com, qemu-devel@nongnu.org, Alexander Graf , borntraeger@de.ibm.com, Igor Mammedov , Paolo Bonzini , Jiri Denemark , rth@twiddle.net, Eduardo Habkost Am 24.06.2015 um 16:19 schrieb Michael S. Tsirkin: > On Wed, Jun 24, 2015 at 11:16:51AM -0300, Eduardo Habkost wrote: >>> IMHO -M pc is not supposed to mean "can break at any time". >> >> It means "it may have new host-side requirements and may become runnab= le >> in your host (or require additional command-line flags to run) at any = time". >=20 > That would be pretty bad. I don't think we ever had such cases in pract= ice. Why is that bad or unexpected? If you install new software, it may have new dependencies. QEMU would be no different from other software there. Yesterday Eduardo said it was about having a fixed version installed and therein switching from a legacy machine to a newer machine. In that case the dependencies existed ever since installation but were not immediately visible to the end user due to our stability guarantees. Andreas --=20 SUSE Linux GmbH, Maxfeldstr. 5, 90409 N=FCrnberg, Germany GF: Felix Imend=F6rffer, Jane Smithard, Dilip Upmanyu, Graham Norton; HRB 21284 (AG N=FCrnberg)