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=-2.3 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, MSGID_FROM_MTA_HEADER,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 665F7C43331 for ; Fri, 3 Apr 2020 11:30:35 +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 33ADC2073B for ; Fri, 3 Apr 2020 11:30:35 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=virtuozzo.com header.i=@virtuozzo.com header.b="mXb1AU9/" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 33ADC2073B Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=virtuozzo.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([::1]:53882 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jKKWw-0000SO-Dg for qemu-devel@archiver.kernel.org; Fri, 03 Apr 2020 07:30:34 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:45847) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1jKKWG-0008IR-05 for qemu-devel@nongnu.org; Fri, 03 Apr 2020 07:29:53 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1jKKWE-0002LS-9S for qemu-devel@nongnu.org; Fri, 03 Apr 2020 07:29:51 -0400 Received: from mail-eopbgr130098.outbound.protection.outlook.com ([40.107.13.98]:52430 helo=EUR01-HE1-obe.outbound.protection.outlook.com) by eggs.gnu.org with esmtps (TLS1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1jKKWD-0002Ki-MH; Fri, 03 Apr 2020 07:29:50 -0400 ARC-Seal: i=1; a=rsa-sha256; s=arcselector9901; d=microsoft.com; cv=none; b=lBAULB6NMyEdHLSnJs8SQTYNUlIdJAFAqbtwUCH59faW+ScmLhK/HjGYSZgq17KQiU5il9dLvDNYOGLMM4t905ARojFw7Q1H81nSWU9s2Me6GjoZJnN4TQpUbrpDZKt+zjQ9V3+bXZch1l10cfCwSlLA1HqmvtF30TLTf/irXC9YnlHVwqItLMKLl6xnZSDEC6zEgPSobaP19ijtfT4bpP3Is6+W4DdaeBSWEVKtm33hhQFpNRfMjG1EX76g7QF5m8phx1vmgqzJTqBeOyFUkKz2WKl6zAdaSxiy2gBjqkzKlXr+KDK9ae1bbTp3yjeD7kX916OfKiGw/bdRNoOYHw== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=microsoft.com; s=arcselector9901; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=4z/TKV0r5hP3dq7rhCmWx4J9TYEPY59IS1emOa3Bs7Q=; b=gCs6qthhSaKisF+XIO+KppWQ8ASysIAL4SFxIeGzWS0DQgc29sRG9IL5J73/JqGKNzhi1NSCMqzRvBLqYTazEbyejfVTxdEXTFXpbLofEy43aG1o/xSDYJ3Ad9IEF6XDkR3oVy4Qj9lT6PeW7Wg9PLBZNdY/vqKQ3D7YRbsRIL2/PQyPAqpF6s8x7aLx3XqT2cEhKF5bVABqLtfxAS3a6EJhdz9V2gSqgNdCQ2hIUdlMDnnnSd3VCwIQ+OY8UWWW84z47HGDb9wWdtQ33/pcmAT/QAVBKr7Kzc6g4dORg61EaOXXTGRANljzo5iDzm2ZmLxSanNdnflMwBqxBm0xeQ== ARC-Authentication-Results: i=1; mx.microsoft.com 1; spf=pass smtp.mailfrom=virtuozzo.com; dmarc=pass action=none header.from=virtuozzo.com; dkim=pass header.d=virtuozzo.com; arc=none DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=virtuozzo.com; s=selector2; h=From:Date:Subject:Message-ID:Content-Type:MIME-Version:X-MS-Exchange-SenderADCheck; bh=4z/TKV0r5hP3dq7rhCmWx4J9TYEPY59IS1emOa3Bs7Q=; b=mXb1AU9/wlnd+Hd4d1z7g6GfLc4OozJM327rvGASnTD4UmDLzE2xhqMmI8W6AqqmlNhK76TWf3vz1sIvK/HAyiD5GeC1oYyFwv0wLCzhASptuchtdUB8xlscgFVcdimS4SkfahfPXfJUw9+SMEtQrp5bRNpQ5p43v5VSkAQedDs= Authentication-Results: spf=none (sender IP is ) smtp.mailfrom=vsementsov@virtuozzo.com; Received: from AM7PR08MB5494.eurprd08.prod.outlook.com (10.141.175.15) by AM7PR08MB5527.eurprd08.prod.outlook.com (10.141.175.146) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2856.20; Fri, 3 Apr 2020 11:29:47 +0000 Received: from AM7PR08MB5494.eurprd08.prod.outlook.com ([fe80::3944:477e:1562:cfcf]) by AM7PR08MB5494.eurprd08.prod.outlook.com ([fe80::3944:477e:1562:cfcf%8]) with mapi id 15.20.2878.016; Fri, 3 Apr 2020 11:29:47 +0000 Subject: Re: [PATCH v2 0/5] fix migration with bitmaps and mirror To: Peter Krempa References: <20191219085106.22309-1-vsementsov@virtuozzo.com> <20191219103638.GJ4914@andariel.pipo.sk> <20200403112358.GV578401@andariel.pipo.sk> From: Vladimir Sementsov-Ogievskiy X-Tagtoolbar-Keys: D20200403142945475 Message-ID: Date: Fri, 3 Apr 2020 14:29:45 +0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.2.1 In-Reply-To: <20200403112358.GV578401@andariel.pipo.sk> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit X-ClientProxiedBy: AM0PR06CA0001.eurprd06.prod.outlook.com (2603:10a6:208:ab::14) To AM7PR08MB5494.eurprd08.prod.outlook.com (2603:10a6:20b:dc::15) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from [192.168.100.2] (185.215.60.62) by AM0PR06CA0001.eurprd06.prod.outlook.com (2603:10a6:208:ab::14) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.2878.15 via Frontend Transport; Fri, 3 Apr 2020 11:29:46 +0000 X-Tagtoolbar-Keys: D20200403142945475 X-Originating-IP: [185.215.60.62] X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: 6987dbd7-9f1f-4ca6-058f-08d7d7c25071 X-MS-TrafficTypeDiagnostic: AM7PR08MB5527: X-MS-Exchange-Transport-Forked: True X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:8273; X-Forefront-PRVS: 0362BF9FDB X-Forefront-Antispam-Report: CIP:255.255.255.255; CTRY:; LANG:en; SCL:1; SRV:; IPV:NLI; SFV:NSPM; H:AM7PR08MB5494.eurprd08.prod.outlook.com; PTR:; CAT:NONE; SFTY:; SFS:(10019020)(4636009)(136003)(366004)(396003)(376002)(346002)(39840400004)(53546011)(316002)(8936002)(186003)(66946007)(31696002)(26005)(478600001)(86362001)(66556008)(31686004)(966005)(16526019)(2616005)(956004)(66476007)(8676002)(4326008)(5660300002)(6486002)(36756003)(6916009)(16576012)(81156014)(2906002)(52116002)(81166006); DIR:OUT; SFP:1102; Received-SPF: None (protection.outlook.com: virtuozzo.com does not designate permitted sender hosts) X-MS-Exchange-SenderADCheck: 1 X-Microsoft-Antispam: BCL:0; X-Microsoft-Antispam-Message-Info: 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 X-MS-Exchange-AntiSpam-MessageData: p+em+J0jFdvCn1DQ+BBckrie+0l+B/TRsjSmeE5lyu6mAix9UZ6xk+hCcnxOZdIvofFu8s/djpSTcl7/jQn5dq/EwfQZz8PEP8NM4sXu5bF2ws1WlL3VpmJxTHXvuZzb89tNJpFMY9zquZWh/CGd3g== X-OriginatorOrg: virtuozzo.com X-MS-Exchange-CrossTenant-Network-Message-Id: 6987dbd7-9f1f-4ca6-058f-08d7d7c25071 X-MS-Exchange-CrossTenant-OriginalArrivalTime: 03 Apr 2020 11:29:47.0969 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 0bc7f26d-0264-416e-a6fc-8352af79c58f X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: Gj4hM7y4FIOSf0F2/HtLZNIArDBMRhVvP5ARGESwbaq+m+hwfsjRlyPNpSCOl++oWWKlRnafd19luKpsh9WOv1RabyWelTTCyIyrjkow7xY= X-MS-Exchange-Transport-CrossTenantHeadersStamped: AM7PR08MB5527 X-detected-operating-system: by eggs.gnu.org: Windows NT kernel [generic] [fuzzy] X-Received-From: 40.107.13.98 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: fam@euphon.net, kwolf@redhat.com, qemu-block@nongnu.org, quintela@redhat.com, dgilbert@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com, den@openvz.org, mreitz@redhat.com Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" 03.04.2020 14:23, Peter Krempa wrote: > On Fri, Apr 03, 2020 at 14:02:47 +0300, Vladimir Sementsov-Ogievskiy wrote: >> 19.12.2019 13:36, Peter Krempa wrote: >>> On Thu, Dec 19, 2019 at 11:51:01 +0300, Vladimir Sementsov-Ogievskiy wrote: >>>> Hi all! >>>> >>>> It's a continuation for >>>> "bitmap migration bug with -drive while block mirror runs" >>>> <315cff78-dcdb-a3ce-2742-da3cc9f0ca97@redhat.com> >>>> https://lists.gnu.org/archive/html/qemu-devel/2019-09/msg07241.html >>>> >>>> The problem is that bitmaps migrated to node with same node-name or >>>> blk-parent name. And currently only the latter actually work in libvirt. >>>> And with mirror-top filter it doesn't work, because >>>> bdrv_get_device_or_node_name don't go through filters. >>> >>> I want to point out that since libvirt-5.10 we use -blockdev to >>> configure the backend of storage devices with qemu-4.2 and later. This >>> means unfortunately that the BlockBackend of the drive does not have a >>> name any more and thus the above will not work even if you make the >>> lookup code to see through filters. >> >> Not that this series doesn't make things worse, as it loops through named >> block backends when trying to use their name for migration. So with these >> patches applied, qemu will just work in more possible scenarios. > > Okay, if that's so it's fair enough in this case. > > I'm just very firmly against baking in the assumption that > node names mean the same thing accross migration, because that will > create a precedent situation and more stuff may be baked in on top of > this in the future. It seems that it has already happened though and > it's wrong. And the worst part is that it's never mentioned that this > might occur. But again, don't do that and preferrably remove the > matching of node names for bitmaps altogether until we can control it > arbitrarily. > > We've also seen this already before with the backend name of memory > devices being baked in to the migration stream which creates an unwanted > dependancy. > Hmm. Actually, matching by node-name never worked. May be just drop it now, and allow only matching by blk-name? And then (in 5.1) implement special qmp commands for precise mapping. -- Best regards, Vladimir