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From:   Dionna Amalie Glaze <dionnaglaze@google.com>
Date:   Mon, 15 May 2023 09:45:10 -0700
Message-ID: <CAAH4kHbLrZZ6xvXYc-TLEyN4pAd=-PL4d2T2yUF318yuh+=_pw@mail.gmail.com>
Subject: Re: [PATCH RFC v7 52/64] KVM: SVM: Provide support for
 SNP_GUEST_REQUEST NAE event
To:     Sean Christopherson <seanjc@google.com>
Cc:     Tom Lendacky <thomas.lendacky@amd.com>,
        Alexey Kardashevskiy <aik@amd.com>,
        Ashish Kalra <ashish.kalra@amd.com>,
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        linux-crypto@vger.kernel.org, x86@kernel.org,
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On Thu, May 11, 2023 at 4:33=E2=80=AFPM Sean Christopherson <seanjc@google.=
com> wrote:
>
> On Thu, May 11, 2023, Dionna Amalie Glaze wrote:
> > Would it be okay to request that we add a KVM stat for how often there
> > are GUEST_REQUEST_NAE exits? I think it'd be good for service
> > operators to get a better idea how valued the feature is.
>
> Heh, it's always ok to request something, but sometimes the answer will b=
e no.
>
> And in the case, the answer is likely "no stat for you".  A year or so ag=
o, in the
> context of us (Google) trying to upstream a pile of stats, we (KVM folks)=
 came to
> a rough consensus that KVM should only add upstream stats if they are rel=
atively
> generic and (almost) universally useful[*].  IMO, a one-off stat for a sp=
ecific exit
> reason is too narrowly focused, e.g. collecting information on all exit r=
easons is
> superior.  And no, that won't be accepted upstream either, because for so=
me environments
> gathering detailed information on all exits is too much overhead (also co=
vered in
> the link).
>
> FWIW, we (GCE) plan on carrying stats like this in out-of-tree patches, i=
.e. your
> request for stats is likely something that would get accepted internally =
(if it
> isn't already captured through our generic stats collection).
>
> [*] https://lore.kernel.org/all/87czp0voqg.wl-maz@kernel.org

Thanks Sean, noted :)

--=20
-Dionna Glaze, PhD (she/her)