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Message-ID: <b172898d-0464-054a-9182-1110297f3629@gmail.com>
Date:   Wed, 23 Feb 2022 19:02:49 +0800
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Subject: Re: [PATCH 1/4] x86/hyperv: Add missing ARCH_HAS_CC_PLATFORM
 dependency
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To:     Borislav Petkov <bp@alien8.de>
Cc:     "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Wei Liu <wei.liu@kernel.org>, tglx@linutronix.de,
        mingo@redhat.com, dave.hansen@intel.com, luto@kernel.org,
        peterz@infradead.org, sathyanarayanan.kuppuswamy@linux.intel.com,
        aarcange@redhat.com, ak@linux.intel.com, dan.j.williams@intel.com,
        david@redhat.com, hpa@zytor.com, jmattson@google.com,
        seanjc@google.com, thomas.lendacky@amd.com, brijesh.singh@amd.com,
        x86@kernel.org, linux-kernel@vger.kernel.org,
        "K. Y. Srinivasan" <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        Stephen Hemminger <sthemmin@microsoft.com>,
        Dexuan Cui <decui@microsoft.com>,
        Tianyu Lan <Tianyu.Lan@microsoft.com>
References: <20220222185740.26228-1-kirill.shutemov@linux.intel.com>
 <20220222185740.26228-2-kirill.shutemov@linux.intel.com>
 <YhVCoveTwsDZXE5G@zn.tnic> <4769a3c0-449b-184a-5c61-a0e155f9c5b4@gmail.com>
 <YhYPPHKZFsGzaI2U@zn.tnic> <bcdbd534-a077-3bb3-3d37-c9eb2a048854@gmail.com>
 <YhYS00FywnE8g4Um@zn.tnic>
From:   Tianyu Lan <ltykernel@gmail.com>
In-Reply-To: <YhYS00FywnE8g4Um@zn.tnic>
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On 2/23/2022 6:56 PM, Borislav Petkov wrote:
> On Wed, Feb 23, 2022 at 06:43:40PM +0800, Tianyu Lan wrote:
>> Hyper-V code check cpuid during runtime and there is no Hyper-V
>> isolation VM option.
> 
> So how does "Current Hyper-V Isolation VM requires AMD_MEM_ENCRYPT" work
> exactly?
> 
> Please explain in detail and not in piecemeal sentences.
>
The kernel in the image needs to select AMD_MEM_ENCRYPT option
otherwise the kernel can't boot up due to missing SEV support and
sev_es_ghcb_hv_call() always return error.