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Date: Thu, 11 Apr 2024 23:41:59 +0800
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Subject: Re: [ANNOUNCE] PUCK Notes - 2024.04.03 - TDX Upstreaming Strategy
To: Sean Christopherson <seanjc@google.com>
Cc: Rick P Edgecombe <rick.p.edgecombe@intel.com>,
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 Isaku Yamahata <isaku.yamahata@intel.com>, Wei W Wang <wei.w.wang@intel.com>
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From: Xiaoyao Li <xiaoyao.li@intel.com>
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On 4/11/2024 11:26 PM, Sean Christopherson wrote:
> On Thu, Apr 11, 2024, Xiaoyao Li wrote:
>> flexible (configurable) bits is known to VMM (KVM and userspace) because TDX
>> module has interface to report them. So we can treat a bit as fixed if it is
>> not reported in the flexible group. (of course the dynamic bits are special
>> and excluded.)
> 
> Does that interface reported the fixed _values_?

No.

But as I said, we can get what the fixed _values_ are after TD is 
initialized by TDH.MNG.INIT via another interface.

Yes. It is a bit late. But at least we have interface to get the fixed 
value runtime instead of hardcoding them.

Meanwhile, we are working internally with TDX architecture team to 
request new interface to report fixed bits and values as the 
configurable bits that doesn't require the TD is initialized. But not 
guarantee on it and not sure when it will be public.