Re: [RFCv2 09/16] KVM: mm: Introduce VM_KVM_PROTECTED

[Kirill A. Shutemov]

On Wed, Oct 21, 2020 at 06:47:32PM +0000, Edgecombe, Rick P wrote:
> On Tue, 2020-10-20 at 09:18 +0300, Kirill A. Shutemov wrote:
> >  include/linux/mm.h  |  8 ++++++++
> >  mm/gup.c            | 20 ++++++++++++++++----
> >  mm/huge_memory.c    | 20 ++++++++++++++++----
> >  mm/memory.c         |  3 +++
> >  mm/mmap.c           |  3 +++
> >  virt/kvm/async_pf.c |  2 +-
> >  virt/kvm/kvm_main.c |  9 +++++----
> >  7 files changed, 52 insertions(+), 13 deletions(-)
> 
> There is another get_user_pages() in
> paging_tmpl.h:FNAME(cmpxchg_gpte). 

Right, I will look into it. I wounder why I don't step onto it.

> Also, did you leave off FOLL_KVM in gfn_to_page_many_atomic() on
> purpose? It looks like its only used for pte prefetch which I guess is
> not required.

FOLL_FAST_ONLY is going to fail anyway. The caller has to handle it
gracefully.

-- 
 Kirill A. Shutemov