[PATCH v1 0/2] udmabuf: Add back support for mapping hugetlb pages

[Jason Gunthorpe]

On Mon, Jun 26, 2023 at 08:14:27PM +0200, David Hildenbrand wrote:

> So we might have to implement the same page migration as gup does on
> FOLL_LONGTERM here ... maybe there are more such cases/drivers that actually
> require that handling when simply taking pages out of the memfd, believing
> they can hold on to them forever.

In general I would like to see an interface to FOLL_LONGTERM pin pages
from a memfd. I would quite happily use that in iommufd as well.

It solves some problems we have there with fork/exec/etc if the pages
are not linked to a mm_struct.

Jason