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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS, T_HK_NAME_DR,URIBL_BLOCKED,USER_AGENT_MUTT 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 1BEA8C31E57 for ; Mon, 17 Jun 2019 10:48:48 +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 E674C2084A for ; Mon, 17 Jun 2019 10:48:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org E674C2084A 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]:46022 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hcpBs-0005oV-Q4 for qemu-devel@archiver.kernel.org; Mon, 17 Jun 2019 06:48:46 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:44480) by lists.gnu.org with esmtp (Exim 4.86_2) (envelope-from ) id 1hcp9y-0005Iu-F8 for qemu-devel@nongnu.org; Mon, 17 Jun 2019 06:46:47 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hcp9x-0004pz-4a for qemu-devel@nongnu.org; Mon, 17 Jun 2019 06:46:46 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57476) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hcp9w-0004Fi-Ry for qemu-devel@nongnu.org; Mon, 17 Jun 2019 06:46:45 -0400 Received: from smtp.corp.redhat.com (int-mx02.intmail.prod.int.phx2.redhat.com [10.5.11.12]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 0AF32149A2; Mon, 17 Jun 2019 10:46:09 +0000 (UTC) Received: from work-vm (ovpn-117-216.ams2.redhat.com [10.36.117.216]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 33968784A6; Mon, 17 Jun 2019 10:46:04 +0000 (UTC) Date: Mon, 17 Jun 2019 11:46:02 +0100 From: "Dr. David Alan Gilbert" To: Peng Tao Message-ID: <20190617104601.GA2679@work-vm> References: <1560494113-1141-1-git-send-email-tao.peng@linux.alibaba.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1560494113-1141-1-git-send-email-tao.peng@linux.alibaba.com> User-Agent: Mutt/1.11.4 (2019-03-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.12 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.38]); Mon, 17 Jun 2019 10:46:14 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH] migration: allow private destination ram with x-ignore-shared 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: Yury Kotov , Xu Wang , qemu-devel@nongnu.org, Jiangshan Lai , kata-dev@lists.katacontainers.io Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" * Peng Tao (tao.peng@linux.alibaba.com) wrote: > 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 I think this is OK, but please post this to qemu-devel. Reviewed-by: Dr. David Alan Gilbert > --- > migration/ram.c | 7 ------- > 1 file changed, 7 deletions(-) > > diff --git a/migration/ram.c b/migration/ram.c > index 1ca9ba7..cdb82a3 100644 > --- a/migration/ram.c > +++ b/migration/ram.c > @@ -3373,7 +3373,6 @@ 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); > } > } > > @@ -4340,12 +4339,6 @@ 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 " > -- > 1.8.3.1 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK