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=-10.3 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,NICE_REPLY_A, SPF_HELO_NONE,SPF_PASS,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 89DFDC4743C for ; Tue, 22 Jun 2021 02:05:25 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 59AD561003 for ; Tue, 22 Jun 2021 02:05:25 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230047AbhFVCHj (ORCPT ); Mon, 21 Jun 2021 22:07:39 -0400 Received: from mga11.intel.com ([192.55.52.93]:14707 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229663AbhFVCHj (ORCPT ); Mon, 21 Jun 2021 22:07:39 -0400 IronPort-SDR: wF2sSkZm2jhURPSwsRDwOzpzOr9gVndzTI0IbcnUOMnAaxiGVrS2isLLs7SwAmczZHbHUPl7Ws 9IBGZogY3Rhw== X-IronPort-AV: E=McAfee;i="6200,9189,10022"; a="203955518" X-IronPort-AV: E=Sophos;i="5.83,290,1616482800"; d="scan'208";a="203955518" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by fmsmga102.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jun 2021 19:05:24 -0700 IronPort-SDR: dLdw0mYa572hkEWgSGeMhCBpF7mlTIUXdEFSv85ioGGyeb0SniKyr3vmVizlAGg4dgBU+dFXJA S/uIZjF15L1w== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,290,1616482800"; d="scan'208";a="490101021" Received: from allen-box.sh.intel.com (HELO [10.239.159.118]) ([10.239.159.118]) by fmsmga002.fm.intel.com with ESMTP; 21 Jun 2021 19:05:18 -0700 Cc: baolu.lu@linux.intel.com, robdclark@chromium.org, linux-kernel@vger.kernel.org, saravanak@google.com, linux-arm-msm@vger.kernel.org, linux-mmc@vger.kernel.org, quic_c_gdjako@quicinc.com, iommu@lists.linux-foundation.org, linux-pci@vger.kernel.org, joel@joelfernandes.org, rajatja@google.com, sonnyrao@chromium.org, vbadigan@codeaurora.org Subject: Re: [PATCH 4/6] iommu: Combine device strictness requests with the global default To: Douglas Anderson , gregkh@linuxfoundation.org, rafael@kernel.org, rafael.j.wysocki@intel.com, will@kernel.org, robin.murphy@arm.com, joro@8bytes.org, bjorn.andersson@linaro.org, ulf.hansson@linaro.org, adrian.hunter@intel.com, bhelgaas@google.com References: <20210621235248.2521620-1-dianders@chromium.org> <20210621165230.4.Id84a954e705fcad3fdb35beb2bc372e4bf2108c7@changeid> From: Lu Baolu Message-ID: Date: Tue, 22 Jun 2021 10:03:45 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101 Thunderbird/78.8.1 MIME-Version: 1.0 In-Reply-To: <20210621165230.4.Id84a954e705fcad3fdb35beb2bc372e4bf2108c7@changeid> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-arm-msm@vger.kernel.org On 6/22/21 7:52 AM, Douglas Anderson wrote: > @@ -1519,7 +1542,8 @@ static int iommu_get_def_domain_type(struct device *dev) > > static int iommu_group_alloc_default_domain(struct bus_type *bus, > struct iommu_group *group, > - unsigned int type) > + unsigned int type, > + struct device *dev) > { > struct iommu_domain *dom; > > @@ -1534,6 +1558,12 @@ static int iommu_group_alloc_default_domain(struct bus_type *bus, > if (!dom) > return -ENOMEM; > > + /* Save the strictness requests from the device */ > + if (dev && type == IOMMU_DOMAIN_DMA) { > + dom->request_non_strict = dev->request_non_strict_iommu; > + dom->force_strict = dev->force_strict_iommu; > + } > + An iommu default domain might be used by multiple devices which might have different "strict" attributions. Then who could override who? Best regards, baolu