Re: [PATCHv3 02/17] mm/khugepaged: Do not collapse pages in encrypted VMAs

From: Dave Hansen
Date: Wed Jun 13 2018 - 13:50:29 EST

On 06/12/2018 07:39 AM, Kirill A. Shutemov wrote:
> Pages for encrypted VMAs have to be allocated in a special way:
> we would need to propagate down not only desired NUMA node but also
> whether the page is encrypted.
> It complicates not-so-trivial routine of huge page allocation in
> khugepaged even more. It also puts more pressure on page allocator:
> we cannot re-use pages allocated for encrypted VMA to collapse
> page in unencrypted one or vice versa.
> I think for now it worth skipping encrypted VMAs. We can return
> to this topic later.

You're asking for this to be included, but without a major piece of THP
support. Is THP support unimportant for this feature?

Are we really asking the x86 maintainers to merge this feature with this
restriction in place?