RE: [PATCH] x86/mm: Print the encryption features correctly when a paravisor is present

[Dexuan Cui]

> From: Dave Hansen <dave.hansen@xxxxxxxxx>
> Sent: Friday, October 20, 2023 11:40 AM
> To: Dexuan Cui <decui@xxxxxxxxxxxxx>; KY Srinivasan
> [...]
> On 10/19/23 23:01, Dexuan Cui wrote:
> > This patch only modifies x86 related files. I think it's unlikely to see
> > a third hardware Coco implementation for x86 in the foreseeable feature
> (?)
> 
> 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.