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Message-ID: <69da742a6970b3b7c4e6feffa91f3162e0c6cf80.camel@infradead.org>
Subject: Re: [PATCH RFC 02/39] KVM: x86/xen: intercept xen hypercalls if
 enabled
From:   David Woodhouse <dwmw2@infradead.org>
To:     Joao Martins <joao.m.martins@oracle.com>
Cc:     Ankur Arora <ankur.a.arora@oracle.com>,
        Boris Ostrovsky <boris.ostrovsky@oracle.com>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        "H. Peter Anvin" <hpa@zytor.com>, x86@kernel.org,
        kvm@vger.kernel.org, linux-kernel@vger.kernel.org
Date:   Wed, 02 Dec 2020 12:12:54 +0000
In-Reply-To: <f30f1f50-9533-1416-e0ef-79f9fbd8d0e5@oracle.com>
References: <20190220201609.28290-1-joao.m.martins@oracle.com>
         <20190220201609.28290-3-joao.m.martins@oracle.com>
         <b56f763e6bf29a65a11b7a36c4d7bfa79b2ec1b2.camel@infradead.org>
         <85c49b9c31f6b74f23ad58f93ec73786b7d48391.camel@infradead.org>
         <f30f1f50-9533-1416-e0ef-79f9fbd8d0e5@oracle.com>
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On Wed, 2020-12-02 at 11:17 +0000, Joao Martins wrote:
> Xen viridian mode is indeed one thing that needed fixing. And definitely =
a
> separate patch as you do here. Both this one and the previous is looking =
good.
>=20
> I suppose that because you switch to kvm_vcpu_write_guest() you no longer=
 need
> to validate that the hypercall page is correct neither marking as dirty. =
Probably
> worth making that explicit in the commit message.

I had intended that to be covered by "open-coding it".

Surely the *point* in using a helper function and not open-coding it is
that we don't *have* to care about the details of what it does ;)


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