Re: [PATCH v6 2/9] mm: x86: add CONFIG_ARCH_HAS_NONLEAF_PMD_YOUNG

[Linus Torvalds]

On Tue, Jan 4, 2022 at 12:23 PM Yu Zhao <yuzhao@xxxxxxxxxx> wrote:
>
> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> index 5c2ccb85f2ef..5a4843242f09 100644
> --- a/arch/x86/Kconfig
> +++ b/arch/x86/Kconfig
> @@ -85,6 +85,7 @@ config X86
> +       select ARCH_HAS_NONLEAF_PMD_YOUNG       if X86_64

Why is this limited to 64-bit?

I'm ok with that - maybe it's a simple case of "this is not worth
doing on 32-bit", but I'd like the explanation to be written out.

Right now the commit message literally points the architecture manual
that sio relevant for both 32-bit and 64-bit - and then the patch
itself makes it 64-bit only.

              Linus