Re: [RFC v2 27/32] x86/tdx: Exclude Shared bit from __PHYSICAL_MASK

From: Kuppuswamy, Sathyanarayanan
Date: Wed May 19 2021 - 01:00:19 EST


Hi Dave,

On 4/26/21 11:01 AM, Kuppuswamy Sathyanarayanan wrote:
From: "Kirill A. Shutemov"<kirill.shutemov@xxxxxxxxxxxxxxx>

tdx_shared_mask() returns the mask that has to be set in a page
table entry to make page shared with VMM.

Also, note that we cannot club shared mapping configuration between
AMD SME and Intel TDX Guest platforms in common function. SME has
to do it very early in __startup_64() as it sets the bit on all
memory, except what is used for communication. TDX can postpone as
we don't need any shared mapping in very early boot.

Signed-off-by: Kirill A. Shutemov<kirill.shutemov@xxxxxxxxxxxxxxx>
Reviewed-by: Andi Kleen<ak@xxxxxxxxxxxxxxx>
Signed-off-by: Kuppuswamy Sathyanarayanan<sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>

Any comments on this patch?

--
Sathyanarayanan Kuppuswamy
Linux Kernel Developer