From: Liu Yi L <yi.l.liu@xxxxxxxxx> [ 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 <yi.l.liu@xxxxxxxxx> Link: https://lore.kernel.org/r/20210817042425.1784279-1-yi.l.liu@xxxxxxxxx Signed-off-by: Lu Baolu <baolu.lu@xxxxxxxxxxxxxxx> Link: https://lore.kernel.org/r/20210818134852.1847070-10-baolu.lu@xxxxxxxxxxxxxxx Signed-off-by: Joerg Roedel <jroedel@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- 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 9ec374e17469..60c07050f6a7 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
