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=-8.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 6AF6BC4332D for ; Fri, 20 Mar 2020 13:45:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3CBC520722 for ; Fri, 20 Mar 2020 13:45:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727303AbgCTNpb (ORCPT ); Fri, 20 Mar 2020 09:45:31 -0400 Received: from mga07.intel.com ([134.134.136.100]:55352 "EHLO mga07.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726843AbgCTNpa (ORCPT ); Fri, 20 Mar 2020 09:45:30 -0400 IronPort-SDR: hUZ8VycuTPqQm9rjkXI3yxRF82TF768XR3aaKmiJyuVsA3vT3QI0NhVM7L3W0JtrZwdqAw/xij qK312uKEyNKg== X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by orsmga105.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Mar 2020 06:45:30 -0700 IronPort-SDR: XWCIulE6yp6+th/bs8uRmyMAA5ISs6gfuFSfB8z5/OVeQIRotVXpkmp9N/LI2idKxn7gzysC3Y cJ1GhGhTDDbw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.72,284,1580803200"; d="scan'208";a="237234057" Received: from che5-mobl.ccr.corp.intel.com (HELO [10.254.213.15]) ([10.254.213.15]) by fmsmga007.fm.intel.com with ESMTP; 20 Mar 2020 06:45:27 -0700 Cc: baolu.lu@linux.intel.com, Raj Ashok , Yi Liu Subject: Re: [PATCH 1/3] iommu/vt-d: Remove redundant IOTLB flush To: Jacob Pan , LKML , iommu@lists.linux-foundation.org, Joerg Roedel , David Woodhouse References: <1584678751-43169-1-git-send-email-jacob.jun.pan@linux.intel.com> <1584678751-43169-2-git-send-email-jacob.jun.pan@linux.intel.com> From: Lu Baolu Message-ID: <26ab1917-f087-aafa-e861-6a2478000a6f@linux.intel.com> Date: Fri, 20 Mar 2020 21:45:26 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.6.0 MIME-Version: 1.0 In-Reply-To: <1584678751-43169-2-git-send-email-jacob.jun.pan@linux.intel.com> Content-Type: text/plain; charset=utf-8; format=flowed Content-Language: en-US Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/3/20 12:32, Jacob Pan wrote: > IOTLB flush already included in the PASID tear down process. There > is no need to flush again. It seems that intel_pasid_tear_down_entry() doesn't flush the pasid based device TLB? Best regards, baolu > > Cc: Lu Baolu > Signed-off-by: Jacob Pan > --- > drivers/iommu/intel-svm.c | 6 ++---- > 1 file changed, 2 insertions(+), 4 deletions(-) > > diff --git a/drivers/iommu/intel-svm.c b/drivers/iommu/intel-svm.c > index 8f42d717d8d7..1483f1845762 100644 > --- a/drivers/iommu/intel-svm.c > +++ b/drivers/iommu/intel-svm.c > @@ -268,10 +268,9 @@ static void intel_mm_release(struct mmu_notifier *mn, struct mm_struct *mm) > * *has* to handle gracefully without affecting other processes. > */ > rcu_read_lock(); > - list_for_each_entry_rcu(sdev, &svm->devs, list) { > + list_for_each_entry_rcu(sdev, &svm->devs, list) > intel_pasid_tear_down_entry(svm->iommu, sdev->dev, svm->pasid); > - intel_flush_svm_range_dev(svm, sdev, 0, -1, 0); > - } > + > rcu_read_unlock(); > > } > @@ -731,7 +730,6 @@ int intel_svm_unbind_mm(struct device *dev, int pasid) > * large and has to be physically contiguous. So it's > * hard to be as defensive as we might like. */ > intel_pasid_tear_down_entry(iommu, dev, svm->pasid); > - intel_flush_svm_range_dev(svm, sdev, 0, -1, 0); > kfree_rcu(sdev, rcu); > > if (list_empty(&svm->devs)) { >