[PATCH AUTOSEL 5.13 44/88] iommu/vt-d: Add present bit check in pasid entry setup helpers
From: Sasha Levin <sashal@kernel.org>
Date: 2021-09-10 00:51:03
Also in:
linux-iommu, lkml
Subsystem:
intel iommu (vt-d), iommu subsystem, the rest · Maintainers:
David Woodhouse, Lu Baolu, Joerg Roedel, Will Deacon, Linus Torvalds
From: Liu Yi L <redacted> [ Upstream commit 423d39d8518c1bba12e0889a92beeddbb1502392 ] The helper functions should not modify the pasid entries which are still in use. Add a check against present bit. Signed-off-by: Liu Yi L <redacted> Link: https://lore.kernel.org/r/20210817042425.1784279-1-yi.l.liu@intel.com (local) Signed-off-by: Lu Baolu <baolu.lu@linux.intel.com> Link: https://lore.kernel.org/r/20210818134852.1847070-10-baolu.lu@linux.intel.com (local) Signed-off-by: Joerg Roedel <redacted> Signed-off-by: Sasha Levin <sashal@kernel.org> --- drivers/iommu/intel/pasid.c | 16 ++++++++++++++++ 1 file changed, 16 insertions(+)
diff --git a/drivers/iommu/intel/pasid.c b/drivers/iommu/intel/pasid.c
index 581c694b7cf4..a4e79d52be27 100644
--- a/drivers/iommu/intel/pasid.c
+++ b/drivers/iommu/intel/pasid.c@@ -540,6 +540,10 @@ void intel_pasid_tear_down_entry(struct intel_iommu *iommu, struct device *dev, devtlb_invalidation_with_pasid(iommu, dev, pasid); } +/* + * This function flushes cache for a newly setup pasid table entry. + * Caller of it should not modify the in-use pasid table entries. + */ static void pasid_flush_caches(struct intel_iommu *iommu, struct pasid_entry *pte, u32 pasid, u16 did)
@@ -591,6 +595,10 @@ int intel_pasid_setup_first_level(struct intel_iommu *iommu, if (WARN_ON(!pte)) return -EINVAL; + /* Caller must ensure PASID entry is not in use. */ + if (pasid_pte_is_present(pte)) + return -EBUSY; + pasid_clear_entry(pte); /* Setup the first level page table pointer: */
@@ -690,6 +698,10 @@ int intel_pasid_setup_second_level(struct intel_iommu *iommu, return -ENODEV; } + /* Caller must ensure PASID entry is not in use. */ + if (pasid_pte_is_present(pte)) + return -EBUSY; + pasid_clear_entry(pte); pasid_set_domain_id(pte, did); pasid_set_slptr(pte, pgd_val);
@@ -729,6 +741,10 @@ int intel_pasid_setup_pass_through(struct intel_iommu *iommu, return -ENODEV; } + /* Caller must ensure PASID entry is not in use. */ + if (pasid_pte_is_present(pte)) + return -EBUSY; + pasid_clear_entry(pte); pasid_set_domain_id(pte, did); pasid_set_address_width(pte, iommu->agaw);
--
2.30.2