Re: [PATCH v7 03/14] mm: Introduce memfile_notifier

Quentin Perret
2022-08-11T12:28:08Z

+CC Fuad

On Wednesday 10 Aug 2022 at 14:38:43 (+0000), Sean Christopherson wrote:
> > I understand Sean's suggestion about abstracting, but if the new name
> > makes it harder to grasp and there isn't really an alternative to memfd
> > in sight, I'm not so sure I enjoy the tried abstraction here.
>
> ARM's pKVM implementation is potentially (hopefully) going to switch to this API
> (as a consumer) sooner than later. If they anticipate being able to use memfd,
> then there's unlikely to be a second backing type any time soon.
>
> Quentin, Will?

Yep, Fuad is currently trying to port the pKVM mm stuff on top of this
series to see how well it fits, so stay tuned. I think there is still
some room for discussion around page conversions (private->shared etc),
and we'll need a clearer idea of what the code might look like to have a
constructive discussion, but so far it does seem like using a memfd (the
new private one or perhaps just memfd_secret, to be discussed) + memfd
notifiers is a promising option.