Re: [PATCH v2 03/14] mm: Convert vmf_insert_mixed() from using pte_devmap to pte_special

[David Hildenbrand]

On 17.06.25 11:49, David Hildenbrand wrote:
> On 16.06.25 13:58, Alistair Popple wrote:
> > DAX no longer requires device PTEs as it always has a ZONE_DEVICE page
> > associated with the PTE that can be reference counted normally. Other users
> > of pte_devmap are drivers that set PFN_DEV when calling vmf_insert_mixed()
> > which ensures vm_normal_page() returns NULL for these entries.
> >
> > There is no reason to distinguish these pte_devmap users so in order to
> > free up a PTE bit use pte_special instead for entries created with
> > vmf_insert_mixed(). This will ensure vm_normal_page() will continue to
> > return NULL for these pages.
> >
> > Architectures that don't support pte_special also don't support pte_devmap
> > so those will continue to rely on pfn_valid() to determine if the page can
> > be mapped.
> >
> > Signed-off-by: Alistair Popple <apopple@xxxxxxxxxx>
> > Reviewed-by: Jason Gunthorpe <jgg@xxxxxxxxxx>
> > Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx>
> > ---

As Andrew notes offlined, there is no content here. I sent this by mistake
after replying to patch#6 instead.

--
Cheers,

David / dhildenb