Re: [PATCH v3 10/15] iommu/amd: Add support for nest parent domain allocation

[Jason Gunthorpe]

On Thu, Oct 09, 2025 at 11:57:50PM +0000, Suravee Suthikulpanit wrote:
> To support nested translation, the nest parent domain is allocated with
> IOMMU_HWPT_ALLOC_NEST_PARENT flag, and stores information of the v1 page
> table for stage 2 (i.e. GPA->SPA).
> 
> Also, only support nest parent domain on AMD system, which can support
> the Guest CR3 Table (GCR3TRPMode) feature. This feature is required in
> order to program DTE[GCR3 Table Root Pointer] with the GPA.
> 
> Reviewed-by: Nicolin Chen <nicolinc@xxxxxxxxxx>
> Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@xxxxxxx>
> ---
>  drivers/iommu/amd/amd_iommu_types.h |  1 +
>  drivers/iommu/amd/iommu.c           | 26 +++++++++++++++++++++++---
>  2 files changed, 24 insertions(+), 3 deletions(-)

Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>

Jason