From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.7 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE autolearn=ham autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id 7CE497D2F0 for ; Thu, 15 Aug 2019 06:56:45 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730478AbfHOG4p (ORCPT ); Thu, 15 Aug 2019 02:56:45 -0400 Received: from mga11.intel.com ([192.55.52.93]:41130 "EHLO mga11.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726098AbfHOG4o (ORCPT ); Thu, 15 Aug 2019 02:56:44 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga102.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 14 Aug 2019 23:56:44 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,388,1559545200"; d="scan'208";a="171034750" Received: from allen-box.sh.intel.com (HELO [10.239.159.136]) ([10.239.159.136]) by orsmga008.jf.intel.com with ESMTP; 14 Aug 2019 23:56:40 -0700 Cc: baolu.lu@linux.intel.com, corbet@lwn.net, tony.luck@intel.com, fenghua.yu@intel.com, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com, x86@kernel.org, linux-doc@vger.kernel.org, linux-ia64@vger.kernel.org, iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Thomas.Lendacky@amd.com, Suravee.Suthikulpanit@amd.com, Joerg Roedel Subject: Re: [PATCH 08/10] iommu: Set default domain type at runtime To: Joerg Roedel References: <20190814133841.7095-1-joro@8bytes.org> <20190814133841.7095-9-joro@8bytes.org> From: Lu Baolu Message-ID: Date: Thu, 15 Aug 2019 14:55:39 +0800 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:60.0) Gecko/20100101 Thunderbird/60.8.0 MIME-Version: 1.0 In-Reply-To: <20190814133841.7095-9-joro@8bytes.org> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Hi, On 8/14/19 9:38 PM, Joerg Roedel wrote: > From: Joerg Roedel > > Set the default domain-type at runtime, not at compile-time. > This keeps default domain type setting in one place when we > have to change it at runtime. > > Signed-off-by: Joerg Roedel > --- > drivers/iommu/iommu.c | 23 +++++++++++++++-------- > 1 file changed, 15 insertions(+), 8 deletions(-) > > diff --git a/drivers/iommu/iommu.c b/drivers/iommu/iommu.c > index 233bc22b487e..96cc7cc8ab21 100644 > --- a/drivers/iommu/iommu.c > +++ b/drivers/iommu/iommu.c > @@ -26,11 +26,8 @@ > > static struct kset *iommu_group_kset; > static DEFINE_IDA(iommu_group_ida); > -#ifdef CONFIG_IOMMU_DEFAULT_PASSTHROUGH > -static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_IDENTITY; > -#else > -static unsigned int iommu_def_domain_type = IOMMU_DOMAIN_DMA; > -#endif > + > +static unsigned int iommu_def_domain_type __read_mostly; > static bool iommu_dma_strict __read_mostly = true; > static u32 iommu_cmd_line __read_mostly; > > @@ -76,7 +73,7 @@ static void iommu_set_cmd_line_dma_api(void) > iommu_cmd_line |= IOMMU_CMD_LINE_DMA_API; > } > > -static bool __maybe_unused iommu_cmd_line_dma_api(void) > +static bool iommu_cmd_line_dma_api(void) > { > return !!(iommu_cmd_line & IOMMU_CMD_LINE_DMA_API); > } > @@ -115,8 +112,18 @@ static const char *iommu_domain_type_str(unsigned int t) > > static int __init iommu_subsys_init(void) > { > - pr_info("Default domain type: %s\n", > - iommu_domain_type_str(iommu_def_domain_type)); > + bool cmd_line = iommu_cmd_line_dma_api(); > + > + if (!cmd_line) { > + if (IS_ENABLED(CONFIG_IOMMU_DEFAULT_PASSTHROUGH)) > + iommu_set_default_passthrough(); > + else > + iommu_set_default_translated(); This overrides kernel parameters parsed in iommu_setup(), for example, iommu=pt won't work anymore. Best regards, Lu Baolu > + } > + > + pr_info("Default domain type: %s %s\n", > + iommu_domain_type_str(iommu_def_domain_type), > + cmd_line ? "(set via kernel command line)" : ""); > > return 0; > } >