Re: [RFC PATCH v2 07/11] iommufd: Use large IOMMU pages for provider mappings

[Fred Griffoul]

On Thu, Oct 15, 2026 at 09:14:48PM -0300, Jason Gunthorpe wrote:
> You are going to need to go into generic_pt and implement cut and a
> more suitable unmap to make this stuff work properly. We can't over
> unmap on conversions.

Agreed. I'll drop this patch from v3 for now.

Just to check I understand what you have in mind: a cut operation in
generic_pt that splits a large entry in place into smaller ones, so
that the revoke unmaps exactly its range, and iommufd uses large pages
only on domains that support it?

> Also please don't write commit messages with AI. WTF is this even
> trying to say? The subject is "use large pages" and this text says
> "map each page with its own call"

Sorry about that. It goes away with the patch, and I'll check and
rewrite the other commit messages for v3.

Fred