From patchwork Fri Jul 12 14:32:07 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Juan Quintela X-Patchwork-Id: 11042393 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 96B5D112C for ; Fri, 12 Jul 2019 14:33:03 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 8429428BF4 for ; Fri, 12 Jul 2019 14:33:03 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 786EB28C1C; Fri, 12 Jul 2019 14:33:03 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-7.9 required=2.0 tests=BAYES_00,MAILING_LIST_MULTI, RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 6440A28BF4 for ; Fri, 12 Jul 2019 14:33:02 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727505AbfGLOdB (ORCPT ); Fri, 12 Jul 2019 10:33:01 -0400 Received: from mx1.redhat.com ([209.132.183.28]:42506 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727538AbfGLOdB (ORCPT ); Fri, 12 Jul 2019 10:33:01 -0400 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 672F34E908; Fri, 12 Jul 2019 14:33:00 +0000 (UTC) Received: from localhost.localdomain (unknown [10.36.118.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id 4E7EA608C2; Fri, 12 Jul 2019 14:32:57 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Cc: Laurent Vivier , Richard Henderson , Paolo Bonzini , kvm@vger.kernel.org, "Dr. David Alan Gilbert" , Juan Quintela , Thomas Huth , Peng Tao , Yury Kotov , Jiangshan Lai , Xu Wang Subject: [PULL 19/19] migration: allow private destination ram with x-ignore-shared Date: Fri, 12 Jul 2019 16:32:07 +0200 Message-Id: <20190712143207.4214-20-quintela@redhat.com> In-Reply-To: <20190712143207.4214-1-quintela@redhat.com> References: <20190712143207.4214-1-quintela@redhat.com> MIME-Version: 1.0 X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Fri, 12 Jul 2019 14:33:00 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP From: Peng Tao By removing the share ram check, qemu is able to migrate to private destination ram when x-ignore-shared capability is on. Then we can create multiple destination VMs based on the same source VM. This changes the x-ignore-shared migration capability to work similar to Lai's original bypass-shared-memory work(https://lists.gnu.org/archive/html/qemu-devel/2018-04/msg00003.html) which enables kata containers (https://katacontainers.io) to implement the VM templating feature. An example usage in kata containers(https://katacontainers.io): 1. Start the source VM: qemu-system-x86 -m 2G \ -object memory-backend-file,id=mem0,size=2G,share=on,mem-path=/tmpfs/template-memory \ -numa node,memdev=mem0 2. Stop the template VM, set migration x-ignore-shared capability, migrate "exec:cat>/tmpfs/state", quit it 3. Start target VM: qemu-system-x86 -m 2G \ -object memory-backend-file,id=mem0,size=2G,share=off,mem-path=/tmpfs/template-memory \ -numa node,memdev=mem0 \ -incoming defer 4. connect to target VM qmp, set migration x-ignore-shared capability, migrate_incoming "exec:cat /tmpfs/state" 5. create more target VMs repeating 3 and 4 Cc: Dr. David Alan Gilbert Cc: Yury Kotov Cc: Jiangshan Lai Cc: Xu Wang Signed-off-by: Peng Tao Reviewed-by: Juan Quintela Reviewed-by: Dr. David Alan Gilbert Message-Id: <1560494113-1141-1-git-send-email-tao.peng@linux.alibaba.com> Signed-off-by: Juan Quintela --- migration/ram.c | 7 ------- 1 file changed, 7 deletions(-) diff --git a/migration/ram.c b/migration/ram.c index 8a6ad61d3d..8622b4dc49 100644 --- a/migration/ram.c +++ b/migration/ram.c @@ -3426,7 +3426,6 @@ static int ram_save_setup(QEMUFile *f, void *opaque) } if (migrate_ignore_shared()) { qemu_put_be64(f, block->mr->addr); - qemu_put_byte(f, ramblock_is_ignored(block) ? 1 : 0); } } @@ -4393,12 +4392,6 @@ static int ram_load(QEMUFile *f, void *opaque, int version_id) } if (migrate_ignore_shared()) { hwaddr addr = qemu_get_be64(f); - bool ignored = qemu_get_byte(f); - if (ignored != ramblock_is_ignored(block)) { - error_report("RAM block %s should %s be migrated", - id, ignored ? "" : "not"); - ret = -EINVAL; - } if (ramblock_is_ignored(block) && block->mr->addr != addr) { error_report("Mismatched GPAs for block %s "