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
