RE: [PATCH v5 10/15] iommupt: Add a mock pagetable format for iommufd selftest to use

Tian, Kevin
2025-09-26T07:50:08Z

> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Thursday, September 4, 2025 1:47 AM
>
> The iommufd self test uses an xarray to store the pfns and their orders to
> emulate a page table. Slightly modify the amdv1 page table to create a
> real page table that has similar properties:
>
> - 2k base granule to simulate something like a 4k page table on a 64K
> PAGE_SIZE ARM system
> - Contiguous page support for every PFN order
> - Dirty tracking
>
> AMDv1 is the closest format, as it is the only one that already supports
> every page size. Tweak it to have only 5 levels and an 11 bit base granule
> and compile it separately as a format variant.
>
> Tested-by: Alejandro Jimenez <alejandro.j.jimenez@oracle.com>
> Signed-off-by: Jason Gunthorpe <jgg@nvidia.com>

Reviewed-by: Kevin Tian <kevin.tian@intel.com>