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Date:   Tue, 15 Mar 2022 06:30:44 -0700
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To:     Isaku Yamahata <isaku.yamahata@gmail.com>,
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From:   Dave Hansen <dave.hansen@intel.com>
Subject: Re: [RFC 0/3] Expose Confidential Computing capabilities on sysfs
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On 3/14/22 15:43, Isaku Yamahata wrote:
>                 xfam_fixed0        fixed-0 value for TD xfam value as a
>                                    hexadecimal number with the "0x" prefix.
>                 xfam_fixed1        fixed-1 value for TD xfam value as a
>                                    hexadecimal number with the "0x" prefix.

I don't think we should be exporting things and creating ABI just for
the heck of it.  These are a prime example.  XFAM is reported to the
guest in CPUID.  Yes, these may be used to help *build* XFAM, but
userspace doesn't need to know how XFAM was built.  It just needs to
know what features it can use.