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=-7.5 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, 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 2E339C433DB for ; Sun, 21 Mar 2021 21:01:54 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 004CD61925 for ; Sun, 21 Mar 2021 21:01:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229955AbhCUVBP (ORCPT ); Sun, 21 Mar 2021 17:01:15 -0400 Received: from smtp-fw-6002.amazon.com ([52.95.49.90]:52568 "EHLO smtp-fw-6002.amazon.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230107AbhCUVAp (ORCPT ); Sun, 21 Mar 2021 17:00:45 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=amazon.com; i=@amazon.com; q=dns/txt; s=amazon201209; t=1616360446; x=1647896446; h=to:cc:references:from:message-id:date:mime-version: in-reply-to:content-transfer-encoding:subject; bh=bR/zGL5bgmIYKJX4KBNvUn1W7VU3s2jvkoCpPNEsc+Y=; b=D+80gHtukbZoYMZx8KbnoPhQyra/OZnnFHS7/XDep9bqxDXTZIR6vCnz QPj3mzZEIsBYjFWqDHndISrWokjBAmCVvGwbjXEttGPPUj/uei55tI48E X+278dJOrIIHhVvRDJopZNwLlJpG4irJX3jgW5vS5CrNLmtVVq33SztIU c=; X-IronPort-AV: E=Sophos;i="5.81,266,1610409600"; d="scan'208";a="99384150" Subject: Re: [net-next 1/2] xen-netback: add module parameter to disable ctrl-ring Received: from iad12-co-svc-p1-lb1-vlan2.amazon.com (HELO email-inbound-relay-1a-821c648d.us-east-1.amazon.com) ([10.43.8.2]) by smtp-border-fw-out-6002.iad6.amazon.com with ESMTP; 21 Mar 2021 21:00:39 +0000 Received: from EX13D12EUA002.ant.amazon.com (iad12-ws-svc-p26-lb9-vlan3.iad.amazon.com [10.40.163.38]) by email-inbound-relay-1a-821c648d.us-east-1.amazon.com (Postfix) with ESMTPS id C740FA1F51; Sun, 21 Mar 2021 21:00:36 +0000 (UTC) Received: from 147dda3ee008.ant.amazon.com (10.43.166.52) by EX13D12EUA002.ant.amazon.com (10.43.165.103) with Microsoft SMTP Server (TLS) id 15.0.1497.2; Sun, 21 Mar 2021 21:00:33 +0000 To: Andrew Lunn CC: Leon Romanovsky , , , , , , References: <20210311225944.24198-1-andyhsu@amazon.com> <64f5c7a8-cc09-3a7f-b33b-a64d373aed60@amazon.com> <12f643b5-7a35-d960-9b1f-22853aea4b4c@amazon.com> From: "Hsu, Chiahao" Message-ID: <818b5f7c-92ce-dca9-ee83-c6220c8292da@amazon.com> Date: Sun, 21 Mar 2021 22:00:21 +0100 User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10.15; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8"; format=flowed Content-Transfer-Encoding: 8bit Content-Language: en-US X-Originating-IP: [10.43.166.52] X-ClientProxiedBy: EX13D10EUA003.ant.amazon.com (10.43.165.52) To EX13D12EUA002.ant.amazon.com (10.43.165.103) Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org Andrew Lunn 於 2021/3/21 21:29 寫道: > CAUTION: This email originated from outside of the organization. Do not click links or open attachments unless you can confirm the sender and know the content is safe. > > > >>> At the end, it will be more granular module parameter that user still >>> will need to guess. >> I believe users always need to know any parameter or any tool's flag before >> they use it. >> For example, before user try to set/clear this ctrl_ring_enabled, they >> should already have basic knowledge about this feature, >> or else they shouldn't use it (the default value is same as before), and >> that's also why we use the 'ctrl_ring_enabled' as parameter name. > To me, it seems you are fixing this problem in the wrong place. As a > VM user in the cloud, i have no idea how the cloud provider needs the > VM configured to allow the cloud provider to migrate the VM to > somewhere else in the bitbarn. As the VM user, it should not be my > problem. I would expect the cloud provider to configure the VM host to > only expose facilities to the VM which allows it to be migrated. 'the users' I mentioned it's the cloud provider, not a VM user. Sorry for the confusion. And agree with you, just wondering how the cloud provider can expose the facilities to the VM if there's no way to set/clr it at runtime, unless reconfigure kernel?  These features are enabled by default. > > This is a VM host problem, not a VM problem. > > Andrew Thanks