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=-15.5 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,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 BCA34C433E6 for ; Thu, 7 Jan 2021 23:54:48 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 972A0235DD for ; Thu, 7 Jan 2021 23:54:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729355AbhAGXyj (ORCPT ); Thu, 7 Jan 2021 18:54:39 -0500 Received: from mga04.intel.com ([192.55.52.120]:43624 "EHLO mga04.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727858AbhAGXyi (ORCPT ); Thu, 7 Jan 2021 18:54:38 -0500 IronPort-SDR: KPzm0TVKueA9LWdFGJxyGzMjkvMTqNn5DmFxjj6o+pJajpsH/tRRrX18t9YtXkh6Ww4648RTmL vyNLgHeM8UcQ== X-IronPort-AV: E=McAfee;i="6000,8403,9857"; a="174935433" X-IronPort-AV: E=Sophos;i="5.79,330,1602572400"; d="scan'208";a="174935433" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jan 2021 15:52:52 -0800 IronPort-SDR: STUYzP1dmLk5rXkzTQFfUHnw4R0sK1nl2mGZ8Xx/VvgmNgfthmWjQSqGTB1GPv3B9u0R6fZTvR qJkph4PCMZ3g== X-IronPort-AV: E=Sophos;i="5.79,330,1602572400"; d="scan'208";a="379907722" Received: from blu2-mobl3.ccr.corp.intel.com (HELO [10.255.31.120]) ([10.255.31.120]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Jan 2021 15:52:49 -0800 Cc: baolu.lu@linux.intel.com, Joerg Roedel , Ashok Raj , Jacob Pan , Guo Kaijie , Liu Yi L , iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org To: Will Deacon References: <20201231005323.2178523-1-baolu.lu@linux.intel.com> <20201231005323.2178523-2-baolu.lu@linux.intel.com> <20210105190357.GA12182@willie-the-truck> From: Lu Baolu Subject: Re: [PATCH 2/5] iommu/vt-d: Fix unaligned addresses for intel_flush_svm_range_dev() Message-ID: <9b26b7ac-b5c7-f38a-a078-b53a6b6bf375@linux.intel.com> Date: Fri, 8 Jan 2021 07:52:47 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:78.0) Gecko/20100101 Thunderbird/78.6.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Will, On 2021/1/6 9:09, Lu Baolu wrote: > Hi Will, > > Happy New Year! > > On 2021/1/6 3:03, Will Deacon wrote: >> On Thu, Dec 31, 2020 at 08:53:20AM +0800, Lu Baolu wrote: >>> The VT-d hardware will ignore those Addr bits which have been masked by >>> the AM field in the PASID-based-IOTLB invalidation descriptor. As the >>> result, if the starting address in the descriptor is not aligned with >>> the address mask, some IOTLB caches might not invalidate. Hence people >>> will see below errors. >>> >>> [ 1093.704661] dmar_fault: 29 callbacks suppressed >>> [ 1093.704664] DMAR: DRHD: handling fault status reg 3 >>> [ 1093.712738] DMAR: [DMA Read] Request device [7a:02.0] PASID 2 >>>                 fault addr 7f81c968d000 [fault reason 113] >>>                 SM: Present bit in first-level paging entry is clear >>> >>> Fix this by using aligned address for PASID-based-IOTLB invalidation. >>> >>> Fixes: 1c4f88b7f1f92 ("iommu/vt-d: Shared virtual address in scalable >>> mode") >>> Reported-and-tested-by: Guo Kaijie >>> Signed-off-by: Lu Baolu >>> --- >>>   drivers/iommu/intel/svm.c | 22 ++++++++++++++++++++-- >>>   1 file changed, 20 insertions(+), 2 deletions(-) >>> >>> diff --git a/drivers/iommu/intel/svm.c b/drivers/iommu/intel/svm.c >>> index 69566695d032..b16a4791acfb 100644 >>> --- a/drivers/iommu/intel/svm.c >>> +++ b/drivers/iommu/intel/svm.c >>> @@ -118,8 +118,10 @@ void intel_svm_check(struct intel_iommu *iommu) >>>       iommu->flags |= VTD_FLAG_SVM_CAPABLE; >>>   } >>> -static void intel_flush_svm_range_dev (struct intel_svm *svm, struct >>> intel_svm_dev *sdev, >>> -                unsigned long address, unsigned long pages, int ih) >>> +static void __flush_svm_range_dev(struct intel_svm *svm, >>> +                  struct intel_svm_dev *sdev, >>> +                  unsigned long address, >>> +                  unsigned long pages, int ih) >>>   { >>>       struct qi_desc desc; >>> @@ -170,6 +172,22 @@ static void intel_flush_svm_range_dev (struct >>> intel_svm *svm, struct intel_svm_d >>>       } >>>   } >>> +static void intel_flush_svm_range_dev(struct intel_svm *svm, >>> +                      struct intel_svm_dev *sdev, >>> +                      unsigned long address, >>> +                      unsigned long pages, int ih) >>> +{ >>> +    unsigned long shift = ilog2(__roundup_pow_of_two(pages)); >>> +    unsigned long align = (1ULL << (VTD_PAGE_SHIFT + shift)); >>> +    unsigned long start = ALIGN_DOWN(address, align); >>> +    unsigned long end = ALIGN(address + (pages << VTD_PAGE_SHIFT), >>> align); >>> + >>> +    while (start < end) { >>> +        __flush_svm_range_dev(svm, sdev, start, align >> >>> VTD_PAGE_SHIFT, ih); >>> +        start += align; >>> +    } >>> +} >> >> Given that this only seems to be called from intel_invalidate_range(), >> which >> has to compute 'pages' only to have it pulled apart again here, >> perhaps it >> would be cleaner for intel_flush_svm_range() to take something like an >> 'order' argument instead? >> >> What do you think? > > We need to clean up here. It's duplicate with the qi_flush_piotlb() > helper. I have a patch under testing for this. I will post it for review > later. I'm sorry, above reply is a little vague. I meant to say, let's take 'pages' as the argument. We are going to use qi_flush_piotlb() here to avoid duplicate QI interactions. The qi_flush_piotlb() helper also takes 'pages', so keep 'pages' here will make things easier. My cleanup patch is for v5.12. Can you please take this for v5.11? Best regards, baolu