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From:   Fuad Tabba <tabba@google.com>
Date:   Wed, 19 Oct 2022 16:02:22 +0100
Message-ID: <CA+EHjTytCEup0m-nhnVHsuQ1xjaCxXNHO_Oxe+QbpwqaewpfKQ@mail.gmail.com>
Subject: Re: [PATCH v8 5/8] KVM: Register/unregister the guest private memory regions
To:     Chao Peng <chao.p.peng@linux.intel.com>
Cc:     Sean Christopherson <seanjc@google.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
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> > > This sounds good. Thank you.
> >
> > I like the idea of a separate Kconfig, e.g. CONFIG_KVM_GENERIC_PRIVATE_MEM or
> > something.  I highly doubt there will be any non-x86 users for multiple years,
> > if ever, but it would allow testing the private memory stuff on ARM (and any other
> > non-x86 arch) without needing full pKVM support and with only minor KVM
> > modifications, e.g. the x86 support[*] to test UPM without TDX is shaping up to be
> > trivial.
>
> CONFIG_KVM_GENERIC_PRIVATE_MEM looks good to me.

That sounds good to me, and just keeping the xarray isn't really an
issue for pKVM. We could end up using it instead of some of the other
structures we use for tracking.

Cheers,
/fuad

> Thanks,
> Chao
> >
> > [*] https://lore.kernel.org/all/Y0mu1FKugNQG5T8K@google.com