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Message-ID: <78bf00d0a25042bd21d1e3d2916ae007c25e9c10.camel@infradead.org>
Subject: Re: [PATCH v10 10/19] KVM: xen: (re-)initialize shared_info if
 guest (32/64-bit) mode is set
From:   David Woodhouse <dwmw2@infradead.org>
To:     Paul Durrant <paul@xen.org>, Paolo Bonzini <pbonzini@redhat.com>,
        Jonathan Corbet <corbet@lwn.net>,
        Sean Christopherson <seanjc@google.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
        Dave Hansen <dave.hansen@linux.intel.com>, x86@kernel.org,
        "H. Peter Anvin" <hpa@zytor.com>, Shuah Khan <shuah@kernel.org>,
        kvm@vger.kernel.org, linux-doc@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org
Date:   Thu, 14 Dec 2023 13:44:40 +0000
In-Reply-To: <20231204144334.910-11-paul@xen.org>
References: <20231204144334.910-1-paul@xen.org>
         <20231204144334.910-11-paul@xen.org>
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On Mon, 2023-12-04 at 14:43 +0000, Paul Durrant wrote:
> From: Paul Durrant <pdurrant@amazon.com>
>=20
> If the shared_info PFN cache has already been initialized then the conten=
t
> of the shared_info page needs to be (re-)initialized whenever the guest
> mode is (re)set.
> Setting the guest mode is either done explicitly by the VMM via the
> KVM_XEN_ATTR_TYPE_LONG_MODE attribute, or implicitly when the guest write=
s
> the MSR to set up the hypercall page.
>=20
> Signed-off-by: Paul Durrant <pdurrant@amazon.com>


Reviewed-by: David Woodhouse <dwmw@amazon.co.uk>

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