Re: [RFC PATCH v2 1/3] mm/huge_memory: make persistent huge zero folio read-only

[Lance Yang]

On 2026/6/11 20:21, David Hildenbrand (Arm) wrote:
> On 6/11/26 13:58, Lance Yang wrote:
> > On Thu, Jun 11, 2026 at 01:28:58PM +0200, David Hildenbrand (Arm) wrote:
> > > On 6/10/26 04:15, Lance Yang wrote:
> > > > Right, this came from the RFC v1 discussion[1]. David preferred a page-
> > > > range helper for possible future non-folio callers, not something folio-
> > > > only.
> > > >
> > > > Of course, we could also add a folio wrapper on top of that if needed :)
> > >
> > > Best to document that as part of the patch description: we don't really expect
> > > to have a lot of read-only folios in the near future (zero page is rather
> > > special; maybe it won't even be a folio in the future).
> >
> > Ah, good to know, thanks. Will spell that out in RFC v3.
> >
> > Maybe something like this?
> >
> > The huge zero page is pretty special case, and maybe it won't even be a
> > folio in the future. Since read-only folios are unlikely to become a
> > common thing, a page-range helper is the cleaner fit.
>
> Right. And if read-only folios in FSes become a real thing, we can always add
> infrastructure for that.

Got it, that draws the line nicely :P