From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-5.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4AE17C433E0 for ; Wed, 3 Feb 2021 10:50:59 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id B691864E2C for ; Wed, 3 Feb 2021 10:50:58 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org B691864E2C Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:60914 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1l7FkP-0003BJ-KW for qemu-devel@archiver.kernel.org; Wed, 03 Feb 2021 05:50:57 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:44728) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1l7Fj6-0002Rs-DJ for qemu-devel@nongnu.org; Wed, 03 Feb 2021 05:49:38 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:29295) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1l7Fj4-0001Dc-0k for qemu-devel@nongnu.org; Wed, 03 Feb 2021 05:49:36 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1612349370; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Rd8w23L+ALOkmDtWFjFkCwnL82N7TJgRX2nzoeJjkPw=; b=dr9Rsic1ChGJTCCNVV0RWn0sXpOGaPawpf1x5e5rSF29egpQaJnBxOdeOphg/gD+u7U7Wy CA9gQ7gUfTXbXqcN02eBdI3QPXPzpWUT/cDmty98kdyF5ErRGVJcoFwpjg7LxzF6JUv6UZ KJH8lzCs5BrPxY2IyibUqO1IwkE4hOg= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-143-CiMASH0eOte2qyn8I8pkFQ-1; Wed, 03 Feb 2021 05:49:29 -0500 X-MC-Unique: CiMASH0eOte2qyn8I8pkFQ-1 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id F3D2B512C; Wed, 3 Feb 2021 10:49:27 +0000 (UTC) Received: from work-vm (ovpn-115-70.ams2.redhat.com [10.36.115.70]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 1BE8B5D9E8; Wed, 3 Feb 2021 10:49:22 +0000 (UTC) Date: Wed, 3 Feb 2021 10:49:20 +0000 From: "Dr. David Alan Gilbert" To: Peter Maydell Subject: Re: ARM Snapshots Not Backwards-Compatible Message-ID: <20210203104920.GE2950@work-vm> References: <153e5c54-f8bf-d088-502d-502309f5d2a6@redhat.com> <20210203102758.GC2950@work-vm> MIME-Version: 1.0 In-Reply-To: User-Agent: Mutt/1.14.6 (2020-07-11) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.14 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=dgilbert@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline Content-Transfer-Encoding: 8bit Received-SPF: pass client-ip=216.205.24.124; envelope-from=dgilbert@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -31 X-Spam_score: -3.2 X-Spam_bar: --- X-Spam_report: (-3.2 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-0.386, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_LOW=-0.7, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Andrew Jones , Juan Quintela , QEMU Developers , Aaron Lindsay , qemu-arm , Philippe =?iso-8859-1?Q?Mathieu-Daud=E9?= Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Peter Maydell (peter.maydell@linaro.org) wrote: > On Wed, 3 Feb 2021 at 10:28, Dr. David Alan Gilbert wrote: > > > > * Philippe Mathieu-Daudé (philmd@redhat.com) wrote: > > > Cc'ing migration team and qemu-arm@ list. > > > > I'll have to leave the detail of that to the ARM peole; but from a > > migration point of view I think we do want the 64 bit ARM migrations to > > be stable now. Please tie incompatible changes to machine types. > > That is the intention, but because there's no upstream testing > of migration compat, we never notice if we get it wrong. > What is x86 doing to keep cross-version migration working ? I know there used to be some of our team running Avocado tests for compatibility regularly, I'm not sure of the current status. It's something we also do regularly around when we do downstream releases, so we tend to catch them then, although even on x86 that often turns out to be a bit late. Avocado can take a separate qemu path for source/destination. Dave > thanks > -- PMM > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK