Re: [PATCH v2 3/3] mm/mempolicy: skip zone device folios when queueing folios

[Gregory Price <gourry@gourry.net>]

On Tue, Aug 18, 2026 at 09:34:49AM +1000, Balbir Singh wrote:
> On Mon, Aug 17, 2026 at 06:08:10PM -0400, Gregory Price wrote:
> > 
> > diff --git a/mm/mempolicy.c b/mm/mempolicy.c
> > index 3498a5651d50f..3418b5664dcf8 100644
> > --- a/mm/mempolicy.c
> > +++ b/mm/mempolicy.c
> > @@ -662,6 +662,8 @@ static void queue_folios_pmd(pmd_t *pmd, struct mm_walk *walk)
> >  		return;
> >  	}
> >  	folio = pmd_folio(pmdval);
> > +	if (folio_is_zone_device(folio))
> > +		return;
> >  	if (is_huge_zero_folio(folio)) {
> >  		walk->action = ACTION_CONTINUE;
> >  		return;
> > -- 
> > 2.53.0-Meta
> >
> 
> 
> A similar patch was sent out earlier, but that was only for zone device
> private THP, we don't support migration of device coherent THP today (we
> should add support). The patch itself makes sense
> 

Yeah IIRC that was Usama's and I got confused thinking this had already
been resolved - but i realized this still affects device coherent.

ty!

~Gregory