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Message-ID: <5263c580-ccfb-4382-936a-e767eeae5af2@intel.com>
Date:   Fri, 20 Oct 2023 13:13:30 -0700
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Subject: Re: [PATCH] x86/mm: Print the encryption features correctly when a
 paravisor is present
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To:     Dexuan Cui <decui@microsoft.com>,
        KY Srinivasan <kys@microsoft.com>,
        Haiyang Zhang <haiyangz@microsoft.com>,
        "wei.liu@kernel.org" <wei.liu@kernel.org>,
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        "dave.hansen@linux.intel.com" <dave.hansen@linux.intel.com>,
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        "luto@kernel.org" <luto@kernel.org>,
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        Tim Gardner <tim.gardner@canonical.com>,
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From:   Dave Hansen <dave.hansen@intel.com>
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On 10/20/23 13:00, Dexuan Cui wrote:
>> OK, then what good is this patch in the first place?  If you are right,
>> then this would give equivalent information:
>>
>> cat /proc/cpuinfo | grep -q Intel && echo 'TDX'
>> cat /proc/cpuinfo | grep -q AMD   && echo 'SEV'
>>
>> No kernel patching needed, right?
> Currently arch/x86/mm/mem_encrypt.c: print_mem_encrypt_feature_info()
> prints an incorrect and confusing message 
> "Memory Encryption Features active: AMD SEV".
> when an Intel TDX VM with a paravisor runs on Hyper-V.
> 
> So I think a kernel patch is needed.

How about either removing the message entirely or removing the ": AMD
SEV" part?