Re: [PATCH v1 02/20] iommu: Introduce a test_dev domain op and an internal helper

Jason Gunthorpe
2025-11-03T18:54:33Z

On Thu, Oct 30, 2025 at 12:43:59PM -0700, Nicolin Chen wrote:

> FWIW, I am thinking of another design based on Jason's remarks:
> https://lore.kernel.org/linux-iommu/aQBopHFub8wyQh5C@Asurada-Nvidia/
>
> So, instead of core initiating the round trip between the blocking
> domain and group->domain, it forwards dev_reset_prepare/done to the
> driver where it does a low-level attachment that wouldn't fail:
> For SMMUv3, it's an STE update.
> For intel_iommu, it seems to be the context table update?

Kevin, how bad do you think the UAPI issue is if we ignore it?

Jason