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=-7.3 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, NICE_REPLY_A,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 D47BEC433FE for ; Mon, 7 Dec 2020 10:15:38 +0000 (UTC) Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) (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 7369D2151B for ; Mon, 7 Dec 2020 10:15:38 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 7369D2151B Authentication-Results: mail.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=suse.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Received: from list by lists.xenproject.org with outflank-mailman.46104.81780 (Exim 4.92) (envelope-from ) id 1kmDYE-0004a8-TD; Mon, 07 Dec 2020 10:15:26 +0000 X-Outflank-Mailman: Message body and most headers restored to incoming version Received: by outflank-mailman (output) from mailman id 46104.81780; Mon, 07 Dec 2020 10:15:26 +0000 Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kmDYE-0004a1-OC; Mon, 07 Dec 2020 10:15:26 +0000 Received: by outflank-mailman (input) for mailman id 46104; Mon, 07 Dec 2020 10:15:25 +0000 Received: from us1-rack-iad1.inumbo.com ([172.99.69.81]) by lists.xenproject.org with esmtp (Exim 4.92) (envelope-from ) id 1kmDYD-0004Zv-7o for xen-devel@lists.xenproject.org; Mon, 07 Dec 2020 10:15:25 +0000 Received: from mx2.suse.de (unknown [195.135.220.15]) by us1-rack-iad1.inumbo.com (Halon) with ESMTPS id 0a5a6bde-27c8-463a-bf4d-459b1adea722; Mon, 07 Dec 2020 10:15:24 +0000 (UTC) Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id A99EEAC55; Mon, 7 Dec 2020 10:15:23 +0000 (UTC) X-BeenThere: xen-devel@lists.xenproject.org List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Errors-To: xen-devel-bounces@lists.xenproject.org Precedence: list Sender: "Xen-devel" X-Inumbo-ID: 0a5a6bde-27c8-463a-bf4d-459b1adea722 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1607336123; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=XS6kqLRvxf+KBioev+tUZsKw3t9Cq5o1WWozwu/1000=; b=awJ5kDavviU3ognfxNE7hNgrAMy5ap7qB2CDbwDnguPx82oBrlZpvdt7jK364LkcPxGNs5 ZpFkiQBFhCOlULu+KMclEuo5zXjiEr+flpPz56WL4mmE/FM9D2XZW9pRh+JP1mkAg5nH36 wZzffaSol5KzA8WvfEz/AHf6iXU52MU= Subject: Re: [PATCH v5 1/4] domctl: introduce a new domain create flag, XEN_DOMCTL_CDF_evtchn_fifo, ... To: Julien Grall Cc: 'Paul Durrant' , 'Eslam Elnikety' , 'Ian Jackson' , 'Wei Liu' , 'Anthony PERARD' , 'Andrew Cooper' , 'George Dunlap' , 'Stefano Stabellini' , 'Christian Lindig' , 'David Scott' , 'Volodymyr Babchuk' , =?UTF-8?B?J1JvZ2VyIFBhdSBNb25uw6kn?= , xen-devel@lists.xenproject.org, paul@xen.org References: <20201203124159.3688-1-paul@xen.org> <20201203124159.3688-2-paul@xen.org> <00ee01d6c98b$507af1c0$f170d540$@xen.org> <8a4a2027-0df3-aee2-537a-3d2814b329ec@suse.com> <00f601d6c996$ce3908d0$6aab1a70$@xen.org> <946280c7-c7f7-c760-c0d3-db91e6cde68a@suse.com> <011201d6ca16$ae14ac50$0a3e04f0$@xen.org> <4fb9fb4c-5849-25f1-ff72-ba3a046d3fd8@suse.com> <63af7714-9c03-35b6-99a1-795b678b8032@xen.org> From: Jan Beulich Message-ID: <93d4ff1c-9f8a-c318-50f8-add2820059d7@suse.com> Date: Mon, 7 Dec 2020 11:15:25 +0100 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.5.1 MIME-Version: 1.0 In-Reply-To: <63af7714-9c03-35b6-99a1-795b678b8032@xen.org> Content-Type: text/plain; charset=utf-8 Content-Language: en-US Content-Transfer-Encoding: 7bit On 07.12.2020 11:04, Julien Grall wrote: > On 07/12/2020 09:17, Jan Beulich wrote: >> On 04.12.2020 12:45, Julien Grall wrote: >>> You are making the assumption that the customer would have the choice to >>> target a specific versions of Xen. This may be undesirable for a cloud >>> provider as suddenly your customer may want to stick on the old version >>> of Xen. >> >> I've gone from you saying "You really need a solution that can restore >> the old VM environment, at least temporarily, for that customer." The >> "temporarily" to me implies that it is at least an option to tie a >> certain guest to a certain Xen version for in-guest upgrading purposes. > > >> If the deal with the customer doesn't include running on a certain Xen >> version, I don't see how this could have non-temporary consequences to >> the cloud provider. > > I think by "you", you mean Paul and not me? Oh, right, I didn't pay attention to who wrote that text. Sorry. Jan