Re: [PATCH v7 1/3] mm: make persistent huge zero folio read-only

[Xueyuan Chen]

On Thu, Sep 3, 2026 at 10:09 PM Dave Hansen <dave.hansen@xxxxxxxxx> wrote:
>
> On 9/3/26 02:20, Mike Rapoport wrote:
> > On Wed, Sep 02, 2026 at 01:59:15PM -0700, Dave Hansen wrote:
> >> On 9/1/26 08:18, Xueyuan Chen wrote:
> >>> +static inline int set_direct_map_ro(struct page *page, unsigned int nr)
> >>> +{
> >>> +   return 0;
> >>> +}
> >> I still really think the stub here needs to return an error *or* the
> >> thing needs to just be void and tell folks that they can't know whether
> >> it worked or not.
> > All other stubs return 0 here when an arch does not support set_direct_map.
> > I'm for keeping them all consistent and fixing that technical debt as a
> > whole rather than creating a one-off here.
>
> Oof. I didn't realize the set_direct_map_*() functions all did this.
>
> I do think it's generally a bad idea, and I'm also OK if it is not fixed
> up here.

OK, I'll leave it as-is then.

Thanks,
Xueyuan