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Message-ID: <d5f95b6b-df7f-416f-14c0-b4e284125d2a@intel.com>
Date:   Mon, 21 Nov 2022 13:01:45 -0800
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Subject: Re: [PATCH 4/6] x86/hyperv: Add hv_isolation_type_tdx() to detect TDX
 guests
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To:     Dexuan Cui <decui@microsoft.com>, ak@linux.intel.com,
        arnd@arndb.de, bp@alien8.de, brijesh.singh@amd.com,
        dan.j.williams@intel.com, dave.hansen@linux.intel.com,
        haiyangz@microsoft.com, hpa@zytor.com, jane.chu@oracle.com,
        kirill.shutemov@linux.intel.com, kys@microsoft.com,
        linux-arch@vger.kernel.org, linux-hyperv@vger.kernel.org,
        luto@kernel.org, mingo@redhat.com, peterz@infradead.org,
        rostedt@goodmis.org, sathyanarayanan.kuppuswamy@linux.intel.com,
        seanjc@google.com, tglx@linutronix.de, tony.luck@intel.com,
        wei.liu@kernel.org, x86@kernel.org
Cc:     linux-kernel@vger.kernel.org
References: <20221121195151.21812-1-decui@microsoft.com>
 <20221121195151.21812-5-decui@microsoft.com>
From:   Dave Hansen <dave.hansen@intel.com>
In-Reply-To: <20221121195151.21812-5-decui@microsoft.com>
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On 11/21/22 11:51, Dexuan Cui wrote:
> +			switch (hv_get_isolation_type()) {
> +			case HV_ISOLATION_TYPE_VBS:
> +			case HV_ISOLATION_TYPE_SNP:
>  				cc_set_vendor(CC_VENDOR_HYPERV);
> +				break;
> +
> +			case HV_ISOLATION_TYPE_TDX:
> +				static_branch_enable(&isolation_type_tdx);
> +				break;

This makes zero logical sense to me.

Running on Hyper-V, a HV_ISOLATION_TYPE_SNP is CC_VENDOR_HYPERV, but a
HV_ISOLATION_TYPE_TDX guest is *NOT* CC_VENDOR_HYPERV?