From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lu Baolu Subject: [PATCH v1 8/9] iommu/vt-d: Flush IOTLB for untrusted device in time Date: Tue, 12 Mar 2019 14:00:04 +0800 Message-ID: <20190312060005.12189-9-baolu.lu@linux.intel.com> References: <20190312060005.12189-1-baolu.lu@linux.intel.com> Return-path: In-Reply-To: <20190312060005.12189-1-baolu.lu@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org To: David Woodhouse , Joerg Roedel , ashok.raj@intel.com, jacob.jun.pan@intel.com, alan.cox@intel.com, kevin.tian@intel.com, mika.westerberg@linux.intel.com, pengfei.xu@intel.com Cc: iommu@lists.linux-foundation.org, linux-kernel@vger.kernel.org, Lu Baolu , Jacob Pan List-Id: iommu@lists.linux-foundation.org By default, for performance consideration, Intel IOMMU driver won't flush IOTLB immediately after a buffer is unmapped. It schedules a thread and flushes IOTLB in a batched mode. This isn't suitable for untrusted device since it still can access the memory even if it isn't supposed to do so. Cc: Ashok Raj Cc: Jacob Pan Signed-off-by: Lu Baolu Tested-by: Xu Pengfei Tested-by: Mika Westerberg --- drivers/iommu/intel-iommu.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/intel-iommu.c b/drivers/iommu/intel-iommu.c index 36909f8e7788..4f2fdd68658c 100644 --- a/drivers/iommu/intel-iommu.c +++ b/drivers/iommu/intel-iommu.c @@ -3749,10 +3749,14 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size) unsigned long iova_pfn; struct intel_iommu *iommu; struct page *freelist; + struct pci_dev *pdev = NULL; if (iommu_no_mapping(dev)) return; + if (dev_is_pci(dev)) + pdev = to_pci_dev(dev); + domain = find_domain(dev); BUG_ON(!domain); @@ -3768,7 +3772,7 @@ static void intel_unmap(struct device *dev, dma_addr_t dev_addr, size_t size) freelist = domain_unmap(domain, start_pfn, last_pfn); - if (intel_iommu_strict) { + if (intel_iommu_strict || (pdev && pdev->untrusted)) { iommu_flush_iotlb_psi(iommu, domain, start_pfn, nrpages, !freelist, 0); /* free iova */ -- 2.17.1