This is a note to let you know that I've just added the patch titled iommu/vt-d: Unconditionally flush device TLB for pasid table updates to the 6.11-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-unconditionally-flush-device-tlb-for-pasi.patch and it can be found in the queue-6.11 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b5f7c9a1e1e61ee5540b847d9083cd9d616d2ca2 Author: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Date: Mon Sep 2 10:27:20 2024 +0800 iommu/vt-d: Unconditionally flush device TLB for pasid table updates [ Upstream commit 1f5e307ca16c0c19186cbd56ac460a687e6daba0 ] The caching mode of an IOMMU is irrelevant to the behavior of the device TLB. Previously, commit <304b3bde24b5> ("iommu/vt-d: Remove caching mode check before device TLB flush") removed this redundant check in the domain unmap path. Checking the caching mode before flushing the device TLB after a pasid table entry is updated is unnecessary and can lead to inconsistent behavior. Extends this consistency by removing the caching mode check in the pasid table update path. Suggested-by: Yi Liu <yi.l.liu@xxxxxxxxx> Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240820030208.20020-1-baolu.lu@xxxxxxxxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c index b51fc268dc845..2e5fa0a232999 100644 --- a/drivers/iommu/intel/pasid.c +++ b/drivers/iommu/intel/pasid.c @@ -264,9 +264,7 @@ void intel_pasid_tear_down_entry(struct intel_iommu *iommu, struct device *dev, else iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH); - /* Device IOTLB doesn't need to be flushed in caching mode. */ - if (!cap_caching_mode(iommu->cap)) - devtlb_invalidation_with_pasid(iommu, dev, pasid); + devtlb_invalidation_with_pasid(iommu, dev, pasid); } /* @@ -493,9 +491,7 @@ int intel_pasid_setup_dirty_tracking(struct intel_iommu *iommu, iommu->flush.flush_iotlb(iommu, did, 0, 0, DMA_TLB_DSI_FLUSH); - /* Device IOTLB doesn't need to be flushed in caching mode. */ - if (!cap_caching_mode(iommu->cap)) - devtlb_invalidation_with_pasid(iommu, dev, pasid); + devtlb_invalidation_with_pasid(iommu, dev, pasid); return 0; } @@ -572,9 +568,7 @@ void intel_pasid_setup_page_snoop_control(struct intel_iommu *iommu, pasid_cache_invalidation_with_pasid(iommu, did, pasid); qi_flush_piotlb(iommu, did, pasid, 0, -1, 0); - /* Device IOTLB doesn't need to be flushed in caching mode. */ - if (!cap_caching_mode(iommu->cap)) - devtlb_invalidation_with_pasid(iommu, dev, pasid); + devtlb_invalidation_with_pasid(iommu, dev, pasid); } /**