Date:   Mon, 3 Jan 2022 16:47:52 -0600
From:   Venu Busireddy <venu.busireddy@oracle.com>
To:     Brijesh Singh <brijesh.singh@amd.com>
Cc:     x86@kernel.org, linux-kernel@vger.kernel.org, kvm@vger.kernel.org,
        linux-efi@vger.kernel.org, platform-driver-x86@vger.kernel.org,
        linux-coco@lists.linux.dev, linux-mm@kvack.org,
        Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, Joerg Roedel <jroedel@suse.de>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        "H. Peter Anvin" <hpa@zytor.com>, Ard Biesheuvel <ardb@kernel.org>,
        Paolo Bonzini <pbonzini@redhat.com>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Jim Mattson <jmattson@google.com>,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Sergio Lopez <slp@redhat.com>, Peter Gonda <pgonda@google.com>,
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        Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com>,
        David Rientjes <rientjes@google.com>,
        Dov Murik <dovmurik@linux.ibm.com>,
        Tobin Feldman-Fitzthum <tobin@ibm.com>,
        Borislav Petkov <bp@alien8.de>,
        Michael Roth <michael.roth@amd.com>,
        Vlastimil Babka <vbabka@suse.cz>,
        "Kirill A . Shutemov" <kirill@shutemov.name>,
        Andi Kleen <ak@linux.intel.com>,
        "Dr . David Alan Gilbert" <dgilbert@redhat.com>,
        tony.luck@intel.com, marcorr@google.com,
        sathyanarayanan.kuppuswamy@linux.intel.com
Subject: Re: [PATCH v8 11/40] x86/sev: Register GHCB memory when SEV-SNP is
 active
Message-ID: <YdN9GNLQiajXbV7U@dt>
References: <20211210154332.11526-1-brijesh.singh@amd.com>
 <20211210154332.11526-12-brijesh.singh@amd.com>
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On 2021-12-10 09:43:03 -0600, Brijesh Singh wrote:
> The SEV-SNP guest is required by the GHCB spec to register the GHCB's
> Guest Physical Address (GPA). This is because the hypervisor may prefer
> that a guest use a consistent and/or specific GPA for the GHCB associated
> with a vCPU. For more information, see the GHCB specification section
> "GHCB GPA Registration".
> 
> Signed-off-by: Brijesh Singh <brijesh.singh@amd.com>

Reviewed-by: Venu Busireddy <venu.busireddy@oracle.com>

> ---
>  arch/x86/include/asm/sev.h   |   2 +
>  arch/x86/kernel/cpu/common.c |   4 ++
>  arch/x86/kernel/head64.c     |   1 +
>  arch/x86/kernel/sev-shared.c |   2 +-
>  arch/x86/kernel/sev.c        | 120 ++++++++++++++++++++---------------
>  5 files changed, 77 insertions(+), 52 deletions(-)
>