Re: [PATCH v2] iommu/amd: Set translation valid bit only when IO page tables are in used

From: Suravee Suthikulpanit
Date: Wed May 25 2022 - 23:29:32 EST


Joerg,

On 5/20/22 3:09 PM, Joerg Roedel wrote:
Hi Suravee,

On Mon, May 16, 2022 at 07:27:51PM +0700, Suravee Suthikulpanit wrote:

- Also, it seems that the current iommu v2 page table use case, where GVA->GPA=SPA
will no longer be supported on system w/ SNPSup=1. Any thoughts?

Support for that is not upstream yet, it should be easy to disallow this
configuration and just use the v1 page-tables when SNP is active. This
can be handled entirely inside the AMD IOMMU driver.


Actually, I am referring to when user uses the IOMMU v2 table for shared virtual address
in current iommu_v2 driver (e.g. amd_iommu_init_device(), amd_iommu_bind_pasid).

Best Regards,
Suravee