Re: [PATCH v3 7/7] iommu/amd: Do not support IOMMUv2 APIs when SNP is enabled

[Joerg Roedel]

On Wed, Jun 22, 2022 at 12:11:31PM -0500, Suravee Suthikulpanit wrote:
>  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;

IOMMU_v2 APIs could actually be supported with GIOV and IOMMUv2
page-tables in-use, no?

Regards,

	Joerg