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=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,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 0CE05C04E84 for ; Wed, 15 May 2019 06:53:05 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id D6C6220862 for ; Wed, 15 May 2019 06:53:04 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org D6C6220862 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=linux.intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:60592 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQnmi-00059k-6s for qemu-devel@archiver.kernel.org; Wed, 15 May 2019 02:53:04 -0400 Received: from eggs.gnu.org ([209.51.188.92]:50802) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQnih-0001gL-10 for qemu-devel@nongnu.org; Wed, 15 May 2019 02:48:56 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hQnZ9-0006rX-H1 for qemu-devel@nongnu.org; Wed, 15 May 2019 02:39:04 -0400 Received: from mga12.intel.com ([192.55.52.136]:14924) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hQnZ9-0006jE-4t for qemu-devel@nongnu.org; Wed, 15 May 2019 02:39:03 -0400 X-Amp-Result: UNKNOWN X-Amp-Original-Verdict: FILE UNKNOWN X-Amp-File-Uploaded: False Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga106.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 May 2019 23:39:00 -0700 X-ExtLoop1: 1 Received: from richard.sh.intel.com (HELO localhost) ([10.239.159.54]) by orsmga005.jf.intel.com with ESMTP; 14 May 2019 23:38:59 -0700 Date: Wed, 15 May 2019 14:38:27 +0800 From: Wei Yang To: "Dr. David Alan Gilbert" Message-ID: <20190515063827.GB11845@richard> References: <20190424004700.12766-1-richardw.yang@linux.intel.com> <20190424004700.12766-3-richardw.yang@linux.intel.com> <0eb5e5a5-593e-f4a2-7e2d-a9fed481ab6c@gmail.com> <20190426005133.GB25513@richard> <20190514151813.GL2753@work-vm> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20190514151813.GL2753@work-vm> User-Agent: Mutt/1.10.1 (2018-07-13) X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 192.55.52.136 Subject: Re: [Qemu-devel] [PATCH 2/4] migration/savevm: use migration_is_blocked to validate X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Reply-To: Wei Yang Cc: quintela@redhat.com, Daniel Henrique Barboza , Wei Yang , qemu-devel@nongnu.org Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Tue, May 14, 2019 at 04:18:14PM +0100, Dr. David Alan Gilbert wrote: >* Wei Yang (richardw.yang@linux.intel.com) wrote: >> >> Well, when you look into the source side of migration: >> >> qmp_migrate >> migrate_prepare >> migration_is_blocked >> >> This means if migration_is_blocked fails, the source will not start migration. >> And it is the same as save_snapshot. >> >> From my understanding, when we load a vm, it should check the same >> requirement. > >I've been thinking about this, and I think I agree with Daniel on this. >The 'migration_blockers' list tells you that something about the >*current* state of a device means that it can't be migrated - e.g. >a 9pfs with a mounted filesystem can't be migrated. > >If we're about to reload the state from a snapshot, then the saved >snapshot's state must have been migratable, so that's OK. > The situation is on a vm with 'migration_blockers' still could reload from a snapshot. This sounds reasonable. Thanks :-) >(Whether all the device code is actually OK about being reset in >that state is a different question; but I think it should be). > >Dave > >> -- >> Wei Yang >> Help you, Help me >-- >Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK -- Wei Yang Help you, Help me