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Date:   Tue, 15 Feb 2022 15:41:10 +0100
From:   Borislav Petkov <bp@alien8.de>
To:     "Kirill A. Shutemov" <kirill@shutemov.name>
Cc:     Brijesh Singh <brijesh.singh@amd.com>, x86@kernel.org,
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        Jim Mattson <jmattson@google.com>,
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Subject: Re: [PATCH v10 21/45] x86/mm: Add support to validate memory when
 changing C-bit
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On Tue, Feb 15, 2022 at 04:15:22PM +0300, Kirill A. Shutemov wrote:
> I have no problem with cc_vendor idea. It looks good.

Good.

> Regarding the masks, if we want to have common ground here we can add two
> mask: cc_enc_mask and cc_dec_mask. And then

If we do two masks, then we can just as well leave the SME and TDX
masks. The point of the whole exercise is to have simpler code and less
ifdeffery.

If you "hide" how the mask works on each vendor in the respective
functions - and yes, cc_pgprot_dec/enc() reads better - then it doesn't
matter how the mask is defined.

Because you don't need two masks to encrypt/decrypt pages - you need a
single mask but apply it differently.

Thx.

-- 
Regards/Gruss,
    Boris.

https://people.kernel.org/tglx/notes-about-netiquette