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Subject: Re: [PATCH] x86/sev: Add AMD_SEV_ES_GUEST Kconfig for including
 SEV-ES support
To:     Borislav Petkov <bp@alien8.de>,
        Sean Christopherson <seanjc@google.com>
Cc:     Thomas Gleixner <tglx@linutronix.de>,
        Ingo Molnar <mingo@redhat.com>, x86@kernel.org,
        Andy Lutomirski <luto@kernel.org>,
        Dave Hansen <dave.hansen@linux.intel.com>,
        Peter Zijlstra <peterz@infradead.org>,
        "H. Peter Anvin" <hpa@zytor.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Jim Mattson <jmattson@google.com>,
        Joerg Roedel <joro@8bytes.org>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org, Tom Lendacky <thomas.lendacky@amd.com>,
        Brijesh Singh <brijesh.singh@amd.com>
References: <20210116002517.548769-1-seanjc@google.com>
 <20210118202931.GI30090@zn.tnic>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <5f7bbd70-35c3-24ca-7ec5-047c71b16b1f@redhat.com>
Date:   Mon, 18 Jan 2021 21:32:07 +0100
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On 18/01/21 21:29, Borislav Petkov wrote:
> On Fri, Jan 15, 2021 at 04:25:17PM -0800, Sean Christopherson wrote:
>> Introduce a new Kconfig, AMD_SEV_ES_GUEST, to control the inclusion of
>> support for running as an SEV-ES guest.  Pivoting on AMD_MEM_ENCRYPT for
>> guest SEV-ES support is undesirable for host-only kernel builds as
>> AMD_MEM_ENCRYPT is also required to enable KVM/host support for SEV and
>> SEV-ES.
> 
> Huh, what?
> 
> I'm not sure I understand what you're trying to say here and am not
> convinced why yet another Kconfig symbol is needed?

I think it makes sense because AMD_SEV_ES_GUEST's #VC handling is quite 
a bit of code that you may not want or need.  The commit message does 
need a rewrite though.

Paolo