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Date:   Thu, 11 Aug 2022 12:27:56 +0000
From:   Quentin Perret <qperret@google.com>
To:     Sean Christopherson <seanjc@google.com>
Cc:     David Hildenbrand <david@redhat.com>,
        Chao Peng <chao.p.peng@linux.intel.com>, kvm@vger.kernel.org,
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        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
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        dhildenb@redhat.com, Michael Roth <michael.roth@amd.com>,
        mhocko@suse.com, Muchun Song <songmuchun@bytedance.com>,
        Will Deacon <will@kernel.org>, Fuad Tabba <tabba@google.com>
Subject: Re: [PATCH v7 03/14] mm: Introduce memfile_notifier
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References: <20220706082016.2603916-1-chao.p.peng@linux.intel.com>
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+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.