Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Subject: Re: [PATCH v5 27/34] KVM: SVM: Add support for booting APs for an
 SEV-ES guest
To:     Tom Lendacky <thomas.lendacky@amd.com>, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, x86@kernel.org
Cc:     Jim Mattson <jmattson@google.com>, Joerg Roedel <joro@8bytes.org>,
        Sean Christopherson <seanjc@google.com>,
        Vitaly Kuznetsov <vkuznets@redhat.com>,
        Wanpeng Li <wanpengli@tencent.com>,
        Borislav Petkov <bp@alien8.de>, Ingo Molnar <mingo@redhat.com>,
        Thomas Gleixner <tglx@linutronix.de>,
        Brijesh Singh <brijesh.singh@amd.com>
References: <cover.1607620209.git.thomas.lendacky@amd.com>
 <47d11ed1c1a48ab71858fc3cde766bf67a4612d1.1607620209.git.thomas.lendacky@amd.com>
 <8ed48a0f-d490-d74d-d10a-968b561a4f2e@redhat.com>
 <2fd11067-a04c-7ce6-3fe1-79a4658bdfe7@amd.com>
 <620a7760-2c4b-c8b9-51e1-8008bf29221d@amd.com>
 <d411beab-b8b2-a7c9-af5b-3722db037910@amd.com>
From:   Paolo Bonzini <pbonzini@redhat.com>
Message-ID: <1433c219-ef19-aa19-7f5c-e872beff7356@redhat.com>
Date:   Mon, 4 Jan 2021 18:50:47 +0100
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:78.0) Gecko/20100101
 Thunderbird/78.5.0
MIME-Version: 1.0
In-Reply-To: <d411beab-b8b2-a7c9-af5b-3722db037910@amd.com>
Content-Type: text/plain; charset=utf-8; format=flowed
Content-Language: en-US
Content-Transfer-Encoding: 7bit
Precedence: bulk

On 04/01/21 18:38, Tom Lendacky wrote:
>>
>> Paolo, is this something along the lines of what you were thinking, or am
>> I off base? I created kvm_emulate_ap_reset_hold() to keep the code
>> consolidated and remove the duplication, but can easily make those 
>> changes
>> local to sev.c. I'd also like to rename SVM_VMGEXIT_AP_HLT_LOOP to
>> SVM_VMGEXIT_AP_RESET_HOLD to more closely match the GHBC document, but
>> that can be done later (if possible, since it is already part of the uapi
>> include file).
> 
> Paolo, a quick ping after the holidays as to whether this is the 
> approach you were thinking. I think there are a couple of places in 
> x86.c to update (vcpu_block() and kvm_arch_vcpu_ioctl_get_mpstate()), also.

Yes, this is the basic idea.

Paolo