This is a note to let you know that I've just added the patch titled iommu/vt-d: Preset Access/Dirty bits for IOVA over FL to the 5.10-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: iommu-vt-d-preset-access-dirty-bits-for-iova-over-fl.patch and it can be found in the queue-5.10 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From a8ce9ebbecdfda3322bbcece6b3b25888217f8e3 Mon Sep 17 00:00:00 2001 From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Date: Fri, 15 Jan 2021 08:42:02 +0800 Subject: iommu/vt-d: Preset Access/Dirty bits for IOVA over FL From: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> commit a8ce9ebbecdfda3322bbcece6b3b25888217f8e3 upstream. The Access/Dirty bits in the first level page table entry will be set whenever a page table entry was used for address translation or write permission was successfully translated. This is always true when using the first-level page table for kernel IOVA. Instead of wasting hardware cycles to update the certain bits, it's better to set them up at the beginning. Suggested-by: Ashok Raj <ashok.raj@xxxxxxxxx> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210115004202.953965-1-baolu.lu@xxxxxxxxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/iommu/intel/iommu.c | 14 ++++++++++++-- include/linux/intel-iommu.h | 2 ++ 2 files changed, 14 insertions(+), 2 deletions(-) --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -1028,8 +1028,11 @@ static struct dma_pte *pfn_to_dma_pte(st domain_flush_cache(domain, tmp_page, VTD_PAGE_SIZE); pteval = ((uint64_t)virt_to_dma_pfn(tmp_page) << VTD_PAGE_SHIFT) | DMA_PTE_READ | DMA_PTE_WRITE; - if (domain_use_first_level(domain)) + if (domain_use_first_level(domain)) { pteval |= DMA_FL_PTE_XD | DMA_FL_PTE_US; + if (domain->domain.type == IOMMU_DOMAIN_DMA) + pteval |= DMA_FL_PTE_ACCESS; + } if (cmpxchg64(&pte->val, 0ULL, pteval)) /* Someone else set it while we were thinking; use theirs. */ free_pgtable_page(tmp_page); @@ -2359,9 +2362,16 @@ static int __domain_mapping(struct dmar_ return -EINVAL; attr = prot & (DMA_PTE_READ | DMA_PTE_WRITE | DMA_PTE_SNP); - if (domain_use_first_level(domain)) + if (domain_use_first_level(domain)) { attr |= DMA_FL_PTE_PRESENT | DMA_FL_PTE_XD | DMA_FL_PTE_US; + if (domain->domain.type == IOMMU_DOMAIN_DMA) { + attr |= DMA_FL_PTE_ACCESS; + if (prot & DMA_PTE_WRITE) + attr |= DMA_FL_PTE_DIRTY; + } + } + if (!sg) { sg_res = nr_pages; pteval = ((phys_addr_t)phys_pfn << VTD_PAGE_SHIFT) | attr; --- a/include/linux/intel-iommu.h +++ b/include/linux/intel-iommu.h @@ -42,6 +42,8 @@ #define DMA_FL_PTE_PRESENT BIT_ULL(0) #define DMA_FL_PTE_US BIT_ULL(2) +#define DMA_FL_PTE_ACCESS BIT_ULL(5) +#define DMA_FL_PTE_DIRTY BIT_ULL(6) #define DMA_FL_PTE_XD BIT_ULL(63) #define ADDR_WIDTH_5LEVEL (57) Patches currently in stable-queue which might be from baolu.lu@xxxxxxxxxxxxxxx are queue-5.10/iommu-vt-d-remove-wo-permissions-on-second-level-paging-entries.patch queue-5.10/revert-iommu-vt-d-remove-wo-permissions-on-second-level.patch queue-5.10/revert-iommu-vt-d-preset-access-dirty-bits-for-iova.patch queue-5.10/iommu-vt-d-preset-access-dirty-bits-for-iova-over-fl.patch