The IOMMUv2 APIs (for supporting shared virtual memory with PASID)
configures the domain with IOMMU v2 page table, and sets DTE[Mode]=0.
This configuration cannot be supported on SNP-enabled system.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpa...@amd.com>
---
drivers/iommu/amd/init.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index a9152d3f33bf..1565f0fb955a 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -3435,7 +3435,12 @@ __setup("ivrs_acpihid", parse_ivrs_acpihid);
bool amd_iommu_v2_supported(void)
{
- return amd_iommu_v2_present;
+ /*
+ * Since DTE[Mode]=0 is prohibited on SNP-enabled system
+ * (i.e. EFR[SNPSup]=1), IOMMUv2 page table cannot be used without
+ * setting up IOMMUv1 page table.
+ */
+ return amd_iommu_v2_present && !amd_iommu_snp_en;
}
EXPORT_SYMBOL(amd_iommu_v2_supported);
--
2.32.0
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