Re: [PATCH v3 00/12] Revise the hwpt lifetime model

[Jason Gunthorpe <jgg@nvidia.com>]

On Wed, Mar 01, 2023 at 03:30:17PM -0400, Jason Gunthorpe wrote:
> As discussed here is a small series to address the confusing lifetime
> scheme for the hwpt. This was some leftover from prior rework that was
> never fully cleaned up.
> 
> Make it clear that the ioas and ioas->hwpt_list are associated with the
> hwpt during creation and never changed until it is destroyed. A hwpt with
> a positive reference count is always valid for device attachment.
> 
> This also improves the selftest handling of the mock domains so that we
> can implement more testing for the hwpt model.
> 
> This is a step toward the nesting and replace series.
> 
> I have this on github:
> 
> https://github.com/jgunthorpe/linux/commits/iommufd_hwpt
> 
> v3:
>  - Split patch to just make the hwpt_item handling consistent
>  - Remove two confusing comments
>  - Four new patches to clean up the confusing 'domain_id' in the selftest
> v2: https://lore.kernel.org/r/0-v2-406f7ac07936+6a-iommufd_hwpt_jgg@nvidia.com
>  - Basically completely different
>  - Add a test for HWPT cases by enhancing the mock iommu driver to be more
>    complete
>  - Move the device attachment as well into iommufd_hw_pagetable_alloc()
>    so destroy is more symmetric
> v1: https://lore.kernel.org/r/0-v1-4336b5cb2fe4+1d7-iommufd_hwpt_jgg@nvidia.com

Applied to iommufd for-next with the noted comment update

Thanks,
Jason