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=-2.3 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,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 18209C43331 for ; Mon, 11 Nov 2019 02:20:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id E758E2067B for ; Mon, 11 Nov 2019 02:20:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726845AbfKKCUV (ORCPT ); Sun, 10 Nov 2019 21:20:21 -0500 Received: from mga11.intel.com ([192.55.52.93]:48162 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726785AbfKKCUV (ORCPT ); Sun, 10 Nov 2019 21:20:21 -0500 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga004.fm.intel.com ([10.253.24.48]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 10 Nov 2019 18:20:20 -0800 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.68,291,1569308400"; d="scan'208";a="228794367" Received: from allen-box.sh.intel.com (HELO [10.239.159.136]) ([10.239.159.136]) by fmsmga004.fm.intel.com with ESMTP; 10 Nov 2019 18:20:19 -0800 Cc: baolu.lu@linux.intel.com, Joerg Roedel , David Woodhouse , kevin.tian@intel.com, ashok.raj@intel.com, linux-kernel@vger.kernel.org, iommu@lists.linux-foundation.org, jacob.jun.pan@intel.com Subject: Re: [PATCH v2 1/1] iommu/vt-d: Add Kconfig option to enable/disable scalable mode To: Qian Cai References: <519c1126-ab91-1308-bdd0-c8d1be7a1c63@linux.intel.com> <2BBFF955-5533-43CD-849A-2BA6B2CC1AF2@lca.pw> From: Lu Baolu Message-ID: <8663cb77-6ec3-fc2a-87bb-3d6629ec1a7f@linux.intel.com> Date: Mon, 11 Nov 2019 10:17:25 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.9.0 MIME-Version: 1.0 In-Reply-To: <2BBFF955-5533-43CD-849A-2BA6B2CC1AF2@lca.pw> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi, On 11/11/19 10:00 AM, Qian Cai wrote: > > >> On Nov 10, 2019, at 8:30 PM, Lu Baolu wrote: >> >> How about "pasid based multiple stages DMA translation"? > > It is better but I am still not sure how developers should select it or not when asking. Ideally, should it mention pros and cons of this? At minimal, there should be a line said “if not sure what this is, select N”? > Actually, I'd recommend "if not sure, use the default value". :-) Best regards, baolu