Re: [RFC PATCH] mm: extend memfd with ability to create "secret" memory areas

Edgecombe, Rick P
2020-02-11T19:52:52Z

On Sat, 2020-02-08 at 19:39 +0200, Mike Rapoport wrote:
> > Do we need to make kmap() work on these?
>
> I don't think we need to make kmap() work on these. The idea is to prevent
> kernel from accessing such memory areas.

For the VM use case, KVM does kmap() guest memory when emulating page table
operations in some cases:
arch/x86/kvm/paging_tmpl.h:FNAME(cmpxchg_gpte).