Hi Longpeng,
On 4/1/21 3:18 PM, Longpeng(Mike) wrote:
diff --git a/drivers/iommu/intel/iommu.c b/drivers/iommu/intel/iommu.c
index ee09323..cbcb434 100644
--- a/drivers/iommu/intel/iommu.c
+++ b/drivers/iommu/intel/iommu.c
@@ -2342,9 +2342,20 @@ static inline int hardware_largepage_caps(struct dmar_domain *domain,
* removed to make room for superpage(s).
* We're adding new large pages, so make sure
* we don't remove their parent tables.
+ *
+ * We also need to flush the iotlb before creating
+ * superpage to ensure it does not perserves any
+ * obsolete info.
*/
- dma_pte_free_pagetable(domain, iov_pfn, end_pfn,
- largepage_lvl + 1);
+ if (dma_pte_present(pte)) {
The dma_pte_free_pagetable() clears a batch of PTEs. So checking current
PTE is insufficient. How about removing this check and always performing
cache invalidation?
+ int i;
+
+ dma_pte_free_pagetable(domain, iov_pfn, end_pfn,
+ largepage_lvl + 1);
+ for_each_domain_iommu(i, domain)
+ iommu_flush_iotlb_psi(g_iommus[i], domain,
+ iov_pfn, nr_pages, 0, 0);
+
Best regards,
baolu
