Re: [PATCH] mm/huge_memory: Initialise the tags of the huge zero folio

[Catalin Marinas <catalin.marinas@arm.com>]

On Mon, Nov 03, 2025 at 03:41:03PM +0100, David Hildenbrand (Red Hat) wrote:
> > diff --git a/arch/arm64/mm/fault.c b/arch/arm64/mm/fault.c
> > index d816ff44faff..125dfa6c613b 100644
> > --- a/arch/arm64/mm/fault.c
> > +++ b/arch/arm64/mm/fault.c
> > @@ -969,6 +969,16 @@ struct folio *vma_alloc_zeroed_movable_folio(struct vm_area_struct *vma,
> >   void tag_clear_highpage(struct page *page)
> >   {
> > +	/*
> > +	 * Check if MTE is supported and fall back to clear_highpage().
> > +	 * get_huge_zero_folio() unconditionally passes __GFP_ZEROTAGS and
> > +	 * post_alloc_hook() will invoke tag_clear_highpage().
> > +	 */
> > +	if (!system_supports_mte()) {
> > +		clear_highpage(page);
> > +		return;
> > +	}
> 
> LGTM!

I tested it with and without MTE and it works fine.

Andrew, would you like a separate patch or are you ok with folding this
into the previous patch?

Thanks.

-- 
Catalin