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Message-ID: <85531c8e-e708-c76a-2d66-30ad7a3f8471@linux.intel.com>
Date:   Thu, 27 Oct 2022 05:40:13 -0700
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Subject: Re: [PATCH v6 16/21] x86/virt/tdx: Reserve TDX module global KeyID
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To:     Kai Huang <kai.huang@intel.com>, linux-kernel@vger.kernel.org,
        kvm@vger.kernel.org
Cc:     linux-mm@kvack.org, seanjc@google.com, pbonzini@redhat.com,
        dave.hansen@intel.com, dan.j.williams@intel.com,
        rafael.j.wysocki@intel.com, kirill.shutemov@linux.intel.com,
        reinette.chatre@intel.com, len.brown@intel.com,
        tony.luck@intel.com, peterz@infradead.org,
        isaku.yamahata@intel.com, chao.gao@intel.com,
        sathyanarayanan.kuppuswamy@linux.intel.com, bagasdotme@gmail.com,
        sagis@google.com, imammedo@redhat.com
References: <cover.1666824663.git.kai.huang@intel.com>
 <7558961d3dff6311c7872f57ac5bd6727f21e140.1666824663.git.kai.huang@intel.com>
From:   Andi Kleen <ak@linux.intel.com>
In-Reply-To: <7558961d3dff6311c7872f57ac5bd6727f21e140.1666824663.git.kai.huang@intel.com>
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On 10/26/2022 4:16 PM, Kai Huang wrote:
> TDX module initialization requires to use one TDX private KeyID as the
> global KeyID to protect the TDX module metadata.  The global KeyID is
> configured to the TDX module along with TDMRs.
>
> Just reserve the first TDX private KeyID as the global KeyID.  Keep the
> global KeyID as a static variable as KVM will need to use it too.
>
> Reviewed-by: Isaku Yamahata <isaku.yamahata@intel.com>
> Signed-off-by: Kai Huang <kai.huang@intel.com>
> ---
>   arch/x86/virt/vmx/tdx/tdx.c | 9 +++++++++
>   1 file changed, 9 insertions(+)
>
> diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
> index 5d74ada072ca..0820ba781f97 100644
> --- a/arch/x86/virt/vmx/tdx/tdx.c
> +++ b/arch/x86/virt/vmx/tdx/tdx.c
> @@ -62,6 +62,9 @@ static struct tdsysinfo_struct tdx_sysinfo;
>   static struct cmr_info tdx_cmr_array[MAX_CMRS] __aligned(CMR_INFO_ARRAY_ALIGNMENT);
>   static int tdx_cmr_num;
>   
> +/* TDX module global KeyID.  Used in TDH.SYS.CONFIG ABI. */
> +static u32 tdx_global_keyid;


Comment how this is serialized (or doesn't need it)