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=-6.8 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED autolearn=ham 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 923A8C76195 for ; Mon, 15 Jul 2019 13:53:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7584B217D9 for ; Mon, 15 Jul 2019 13:53:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1732322AbfGONxP (ORCPT ); Mon, 15 Jul 2019 09:53:15 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39272 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1732302AbfGONxK (ORCPT ); Mon, 15 Jul 2019 09:53:10 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 496FC30C2534; Mon, 15 Jul 2019 13:53:10 +0000 (UTC) Received: from localhost.localdomain (unknown [10.36.118.16]) by smtp.corp.redhat.com (Postfix) with ESMTP id 04F755B681; Mon, 15 Jul 2019 13:53:02 +0000 (UTC) From: Juan Quintela To: qemu-devel@nongnu.org Cc: Paolo Bonzini , kvm@vger.kernel.org, Juan Quintela , Thomas Huth , Richard Henderson , Laurent Vivier , "Dr. David Alan Gilbert" , Peng Tao , Yury Kotov , Jiangshan Lai , Xu Wang Subject: [PULL 18/21] migration: allow private destination ram with x-ignore-shared Date: Mon, 15 Jul 2019 15:51:22 +0200 Message-Id: <20190715135125.17770-19-quintela@redhat.com> In-Reply-To: <20190715135125.17770-1-quintela@redhat.com> References: <20190715135125.17770-1-quintela@redhat.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Scanned-By: MIMEDefang 2.79 on 10.5.11.15 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.40]); Mon, 15 Jul 2019 13:53:10 +0000 (UTC) Sender: kvm-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: kvm@vger.kernel.org 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 " -- 2.21.0