On Wed, Oct 16, 2024 at 04:10:53PM +1100, Alistair Popple wrote: > On that note how is the refcounting of the returned p2pdma page expected > to work? We don't want the driver calling hmm_range_fault() to be able > to pin the page with eg. get_page(), so the returned p2pdma page should > have a zero refcount to enforce that.
I think that is just the rule for hmm stuff in general, don't touch the refcount. We don't need to enforce, it we don't know what else the driver will want to use that P2P page for after all. It might stick it in a VMA for some unrelated reason. Jason
