Re: [PATCH v2 1/3] arm64: mm: use appropriate ctors for page tables

[Matthew Wilcox]

On Mon, Feb 18, 2019 at 10:32:05PM -0700, Yu Zhao wrote:
> pgtable_pmd_page_ctor() must be used on user pmd. For kernel pmd,
> it's okay to use pgtable_page_ctor() instead only because kernel
> doesn't have thp.

I'm not sure that's true.  I think you can create THPs in vmalloc
these days.  See HAVE_ARCH_HUGE_VMAP which is supported by arm64.