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=-10.0 required=3.0 tests=BAYES_00,DKIM_INVALID, DKIM_SIGNED,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 0170FC64E8A for ; Wed, 2 Dec 2020 10:57:48 +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 4F14D221FB for ; Wed, 2 Dec 2020 10:57:47 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 4F14D221FB 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]:40540 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1kkPpS-0006U8-86 for qemu-devel@archiver.kernel.org; Wed, 02 Dec 2020 05:57:46 -0500 Received: from eggs.gnu.org ([2001:470:142:3::10]:53048) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1kkPMJ-0002ob-Hv for qemu-devel@nongnu.org; Wed, 02 Dec 2020 05:27:40 -0500 Received: from us-smtp-delivery-124.mimecast.com ([216.205.24.124]:28213) by eggs.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_CBC_SHA1:256) (Exim 4.90_1) (envelope-from ) id 1kkPMD-0006sy-Ee for qemu-devel@nongnu.org; Wed, 02 Dec 2020 05:27:37 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1606904851; h=from:from:reply-to:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:in-reply-to:in-reply-to: references:references; bh=lSxlnQ2709OFK05FqRtDIwpNRKL9qe7gwojgJLKHNxQ=; b=LjaFKQrJucyE32fUhiBu0I+T2rDvx8I7JBZkhTwVAmtnmrH+XWGJMx8uLdRFSQ1xOPiakO 3dNAqyL00uwMD/r0Hu5Y+Im1MhV4PQ0a/DMZVQx13dxMJqvcrl/C4njx9smnKiqkUd3BMH j/TfTCWO8QxjqJ0OPRAXTLXFzdrE7No= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-121-XSNQ-XdxPkqF3XogEW6_Yg-1; Wed, 02 Dec 2020 05:27:27 -0500 X-MC-Unique: XSNQ-XdxPkqF3XogEW6_Yg-1 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 781C9180A098 for ; Wed, 2 Dec 2020 10:27:26 +0000 (UTC) Received: from redhat.com (ovpn-115-57.ams2.redhat.com [10.36.115.57]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B98B019C48; Wed, 2 Dec 2020 10:27:21 +0000 (UTC) Date: Wed, 2 Dec 2020 10:27:18 +0000 From: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= To: "Michael S. Tsirkin" Subject: Re: [PATCH v2 01/27] migration: Network Failover can't work with a paused guest Message-ID: <20201202102718.GA2360260@redhat.com> References: <20201118083748.1328-1-quintela@redhat.com> <20201118083748.1328-2-quintela@redhat.com> <20201202050918-mutt-send-email-mst@kernel.org> MIME-Version: 1.0 In-Reply-To: <20201202050918-mutt-send-email-mst@kernel.org> User-Agent: Mutt/1.14.6 (2020-07-11) X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 Authentication-Results: relay.mimecast.com; auth=pass smtp.auth=CUSA124A263 smtp.mailfrom=berrange@redhat.com X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Received-SPF: pass client-ip=216.205.24.124; envelope-from=berrange@redhat.com; helo=us-smtp-delivery-124.mimecast.com X-Spam_score_int: -35 X-Spam_score: -3.6 X-Spam_bar: --- X-Spam_report: (-3.6 / 5.0 requ) BAYES_00=-1.9, DKIMWL_WL_HIGH=-1.497, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, RCVD_IN_DNSWL_NONE=-0.0001, RCVD_IN_MSPIKE_H3=0.001, RCVD_IN_MSPIKE_WL=0.001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001 autolearn=ham autolearn_force=no X-Spam_action: no action 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: , Reply-To: Daniel =?utf-8?B?UC4gQmVycmFuZ8Op?= Cc: Eduardo Habkost , Juan Quintela , Jason Wang , "Dr. David Alan Gilbert" , qemu-devel@nongnu.org, Paolo Bonzini Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" On Wed, Dec 02, 2020 at 05:13:18AM -0500, Michael S. Tsirkin wrote: > On Wed, Nov 18, 2020 at 09:37:22AM +0100, Juan Quintela wrote: > > If we have a paused guest, it can't unplug the network VF device, so > > we wait there forever. Just change the code to give one error on that > > case. > > > > Signed-off-by: Juan Quintela > > It's certainly possible but it's management that created > this situation after all - why do we bother to enforce > a policy? It is possible that management will unpause immediately > afterwards and everything will proceed smoothly. > > Yes migration will not happen until guest is > unpaused but the same it true of e.g. a guest that is stuck > because of a bug. That's pretty different behaviour from how migration normally handles a paused guest, which is that it is guaranteed to complete the migration in as short a time as network bandwidth allows. Just ignoring the situation I think will lead to surprise apps / admins, because the person/entity invoking the migration is not likely to have checked wether this particular guest uses net failover or not before invoking - they'll just be expecting a paused migration to run fast and be guaranteed to complete. Regards, Daniel -- |: https://berrange.com -o- https://www.flickr.com/photos/dberrange :| |: https://libvirt.org -o- https://fstop138.berrange.com :| |: https://entangle-photo.org -o- https://www.instagram.com/dberrange :|