On 6/22/2022 12:50 AM, Peter Gonda wrote:
On Tue, Jun 21, 2022 at 11:45 AM Kalra, Ashish <Ashish.Kalra@xxxxxxx> wrote:
[AMD Official Use Only - General]
Hello Peter,
+bool iommu_sev_snp_supported(void)
+{
+ struct amd_iommu *iommu;
+
+ /*
+ * The SEV-SNP support requires that IOMMU must be enabled, and is
+ * not configured in the passthrough mode.
+ */
+ if (no_iommu || iommu_default_passthrough()) {
+ pr_err("SEV-SNP: IOMMU is either disabled or
+ configured in passthrough mode.\n");
Like below could this say something like snp support is disabled because of iommu settings.
Here we may need to be more precise with the error information indicating why SNP is not enabled.
Please note that this patch may actually become part of the IOMMU + SNP patch series, where
additional checks are done, for example, not enabling SNP if IOMMU v2 page tables are enabled,
so precise error information will be useful here.
I agree we should be more precise. I just thought we should explicitly
state something like: "SEV-SNP: IOMMU is either disabled or configured
in passthrough mode, SNP cannot be supported".
I can update this in the other patch series here
https://lists.linuxfoundation.org/pipermail/iommu/2022-June/066399.html
Thank you,
Suravee