Re: [PATCH v7 1/9] mm: Consolidate freeing of typed folios on final folio_put()

[Fuad Tabba <tabba@google.com>]

Hi David,

On Mon, 14 Apr 2025 at 11:00, David Hildenbrand <david@redhat.com> wrote:
>
> On 18.03.25 17:18, Fuad Tabba wrote:
> > Some folio types, such as hugetlb, handle freeing their own
> > folios. Moreover, guest_memfd will require being notified once a
> > folio's reference count reaches 0 to facilitate shared to private
> > folio conversion, without the folio actually being freed at that
> > point.
> >
> > As a first step towards that, this patch consolidates freeing
> > folios that have a type. The first user is hugetlb folios. Later
> > in this patch series, guest_memfd will become the second user of
> > this.
> >
> > Suggested-by: David Hildenbrand <david@redhat.com>
> > Acked-by: Vlastimil Babka <vbabka@suse.cz>
> > Acked-by: David Hildenbrand <david@redhat.com>
> > Signed-off-by: Fuad Tabba <tabba@google.com>
> > ---
>
> As discussed in the last upstream meeting, we should focus on using the
> folio_put() hook only for the post-truncate case where required (e.g.,
> re-assemble hugetlb).
>
> For shared->private conversion doing it synchronously (unmap, try
> freezing refcount) and failing if impossible to signal user space to
> retry is a better first approach.
>
> So this patch will be dropped from your series for now, correct?

Yes it will.

Thanks,
/fuad

> --
> Cheers,
>
> David / dhildenb
>