From 62e062a29ad5133f67c20b333ba0a952a99161ae Mon Sep 17 00:00:00 2001 From: Simon Xue Date: Mon, 23 Jun 2025 10:00:18 +0800 Subject: [PATCH 1/2] iommu/rockchip: prevent iommus dead loop when two masters share one IOMMU When two masters share an IOMMU, calling ops->of_xlate during the second master's driver init may overwrite iommu->domain set by the first. This causes the check if (iommu->domain == domain) in rk_iommu_attach_device() to fail, resulting in the same iommu->node being added twice to &rk_domain->iommus, which can lead to an infinite loop in subsequent &rk_domain->iommus operations. Cc: Fixes: 25c2325575cc ("iommu/rockchip: Add missing set_platform_dma_ops callback") Signed-off-by: Simon Xue Reviewed-by: Robin Murphy Link: https://lore.kernel.org/r/20250623020018.584802-1-xxm@rock-chips.com Signed-off-by: Joerg Roedel --- drivers/iommu/rockchip-iommu.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/iommu/rockchip-iommu.c b/drivers/iommu/rockchip-iommu.c index 22f74ba33a0e..e6bb3c784017 100644 --- a/drivers/iommu/rockchip-iommu.c +++ b/drivers/iommu/rockchip-iommu.c @@ -1157,7 +1157,6 @@ static int rk_iommu_of_xlate(struct device *dev, return -ENOMEM; data->iommu = platform_get_drvdata(iommu_dev); - data->iommu->domain = &rk_identity_domain; dev_iommu_priv_set(dev, data); platform_device_put(iommu_dev); @@ -1195,6 +1194,8 @@ static int rk_iommu_probe(struct platform_device *pdev) if (!iommu) return -ENOMEM; + iommu->domain = &rk_identity_domain; + platform_set_drvdata(pdev, iommu); iommu->dev = dev; iommu->num_mmu = 0; From 25b1b75bbaf96331750fb01302825069657b2ff8 Mon Sep 17 00:00:00 2001 From: Lu Baolu Date: Sat, 28 Jun 2025 18:03:51 +0800 Subject: [PATCH 2/2] iommu/vt-d: Assign devtlb cache tag on ATS enablement Commit <4f1492efb495> ("iommu/vt-d: Revert ATS timing change to fix boot failure") placed the enabling of ATS in the probe_finalize callback. This occurs after the default domain attachment, which is when the ATS cache tag is assigned. Consequently, the device TLB cache tag is missed when the domain is attached, leading to the device TLB not being invalidated in the iommu_unmap paths. Fix this by assigning the CACHE_TAG_DEVTLB cache tag when ATS is enabled. Fixes: 4f1492efb495 ("iommu/vt-d: Revert ATS timing change to fix boot failure") Cc: stable@vger.kernel.org Suggested-by: Kevin Tian Signed-off-by: Lu Baolu Tested-by: Shuicheng Lin Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20250625050135.3129955-1-baolu.lu@linux.intel.com Link: https://lore.kernel.org/r/20250628100351.3198955-2-baolu.lu@linux.intel.com Signed-off-by: Joerg Roedel --- drivers/iommu/intel/cache.c | 5 ++--- drivers/iommu/intel/iommu.c | 11 ++++++++++- drivers/iommu/intel/iommu.h | 2 ++ 3 files changed, 14 insertions(+), 4 deletions(-) diff --git a/drivers/iommu/intel/cache.c b/drivers/iommu/intel/cache.c index fc35cba59145..47692cbfaabd 100644 --- a/drivers/iommu/intel/cache.c +++ b/drivers/iommu/intel/cache.c @@ -40,9 +40,8 @@ static bool cache_tage_match(struct cache_tag *tag, u16 domain_id, } /* Assign a cache tag with specified type to domain. */ -static int cache_tag_assign(struct dmar_domain *domain, u16 did, - struct device *dev, ioasid_t pasid, - enum cache_tag_type type) +int cache_tag_assign(struct dmar_domain *domain, u16 did, struct device *dev, + ioasid_t pasid, enum cache_tag_type type) { struct device_domain_info *info = dev_iommu_priv_get(dev); struct intel_iommu *iommu = info->iommu; diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c index 7aa3932251b2..148b944143b8 100644 --- a/drivers/iommu/intel/iommu.c +++ b/drivers/iommu/intel/iommu.c @@ -3780,8 +3780,17 @@ static void intel_iommu_probe_finalize(struct device *dev) !pci_enable_pasid(to_pci_dev(dev), info->pasid_supported & ~1)) info->pasid_enabled = 1; - if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) + if (sm_supported(iommu) && !dev_is_real_dma_subdevice(dev)) { iommu_enable_pci_ats(info); + /* Assign a DEVTLB cache tag to the default domain. */ + if (info->ats_enabled && info->domain) { + u16 did = domain_id_iommu(info->domain, iommu); + + if (cache_tag_assign(info->domain, did, dev, + IOMMU_NO_PASID, CACHE_TAG_DEVTLB)) + iommu_disable_pci_ats(info); + } + } iommu_enable_pci_pri(info); } diff --git a/drivers/iommu/intel/iommu.h b/drivers/iommu/intel/iommu.h index 3ddbcc603de2..2d1afab5eedc 100644 --- a/drivers/iommu/intel/iommu.h +++ b/drivers/iommu/intel/iommu.h @@ -1289,6 +1289,8 @@ struct cache_tag { unsigned int users; }; +int cache_tag_assign(struct dmar_domain *domain, u16 did, struct device *dev, + ioasid_t pasid, enum cache_tag_type type); int cache_tag_assign_domain(struct dmar_domain *domain, struct device *dev, ioasid_t pasid); void cache_tag_unassign_domain(struct dmar_domain *domain,