From: Jeremi Piotrowski <jpiotrowski@xxxxxxxxxxxxx>
Hyper-V VMs do not have access to an IOMMU but can support hosting SNP
VMs. amd_iommu_snp_enable() is on the SNP init path and should not fail
in that case.
Signed-off-by: Jeremi Piotrowski <jpiotrowski@xxxxxxxxxxxxxxxxxxx>
---
drivers/iommu/amd/init.c | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/drivers/iommu/amd/init.c b/drivers/iommu/amd/init.c
index d1270e3c5baf..8049dbe78a27 100644
--- a/drivers/iommu/amd/init.c
+++ b/drivers/iommu/amd/init.c
@@ -3619,6 +3619,12 @@ int amd_iommu_pc_set_reg(struct amd_iommu *iommu, u8 bank, u8 cntr, u8 fxn, u64
#ifdef CONFIG_AMD_MEM_ENCRYPT
int amd_iommu_snp_enable(void)
{
+ /*
+ * If we're running virtualized there doesn't have to be an IOMMU for SNP to work.
+ */
+ if (init_state == IOMMU_NOT_FOUND && boot_cpu_has(X86_FEATURE_HYPERVISOR))
+ return 0;
+
/*
* The SNP support requires that IOMMU must be enabled, and is
* not configured in the passthrough mode.
--
2.25.1
