From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43241) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V6KRV-00021J-86 for qemu-devel@nongnu.org; Mon, 05 Aug 2013 09:03:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1V6KRP-0007dG-9F for qemu-devel@nongnu.org; Mon, 05 Aug 2013 09:03:21 -0400 Received: from mail-lb0-f171.google.com ([209.85.217.171]:55087) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1V6KRP-0007cu-30 for qemu-devel@nongnu.org; Mon, 05 Aug 2013 09:03:15 -0400 Received: by mail-lb0-f171.google.com with SMTP id t13so2089467lbd.30 for ; Mon, 05 Aug 2013 06:03:14 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <20130805124922.GA5108@redhat.com> References: <1375701492-21759-1-git-send-email-peter.maydell@linaro.org> <20130805124922.GA5108@redhat.com> From: Peter Maydell Date: Mon, 5 Aug 2013 14:02:54 +0100 Message-ID: Content-Type: text/plain; charset=UTF-8 Subject: Re: [Qemu-devel] Versioned machine types for ARM/non-x86 ? (Was Re: [PATCH v4 0/2] ARM: add 'virt' platform) List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: aliguori@us.ibm.com, "Mian M. Hamayun" , patches@linaro.org, Markus Armbruster , qemu-devel@nongnu.org, kvmarm@lists.cs.columbia.edu On 5 August 2013 13:49, Daniel P. Berrange wrote: > On x86, we've long had versioned machine names, so that we can > make changes in future QEMU releases without breaking guest ABI > compatibility. AFAICT, the problem has basically been ignored > on non-x86 platforms in QEMU. Yes; this is deliberate on the basis that starting to do this is accepting a huge pile of maintenance workload (ie checking for things which change, keeping around a pile of old version machine models, retaining migration compatibility between old and new versions). Which isn't to say I'm against it but it means I'm not doing it until the pushback from users that it's necessary is pretty strong. > Given the increased interest in > ARM in particular, should we use the addition of this new 'virt' > machine type, as an opportunity to introduce versioning for > ARM too. eg make this machine be called 'virt-1.0.6' and then > have 'virt' simply be an alias that points to the most recent > version. I'm not convinced we're at the point where we need to do this yet. -- PMM