Re: [PATCH mm-new v3 1/1] mm/khugepaged: abort collapse scan on non-swap entries

[Lance Yang]

On 2025/10/14 22:32, David Hildenbrand wrote:
> > static inline int pte_protnone(pte_t pte)
> > {
> >     return (pte_flags(pte) & (_PAGE_PROTNONE | _PAGE_PRESENT))
> >         == _PAGE_PROTNONE;
> > }
> >
> > static inline int pte_present(pte_t a)
> > {
> >     return pte_flags(a) & (_PAGE_PRESENT | _PAGE_PROTNONE);
> > }
> > ```
> >
> > On x86, pte_present() returns true for a protnone pte. And I'd assume
> > other archs behave similarly ...
>
> Applies to all architecture. prot-none entries must be present, 
> otherwise we'd have a lot of other issues :)

Thanks for confirming, David! That's good to know ;p

So @Lorenzo, looks like we're good here on the protnone front. Does
that clear up your concern?