Re: [PATCHv6 02/15] mm: Add support for unaccepted memory

From: Andrew Morton
Date: Tue May 17 2022 - 13:45:27 EST


On Tue, 17 May 2022 18:34:31 +0300 "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> wrote:

> UEFI Specification version 2.9 introduces the concept of memory
> acceptance. Some Virtual Machine platforms, such as Intel TDX or AMD
> SEV-SNP, require memory to be accepted before it can be used by the
> guest. Accepting happens via a protocol specific to the Virtual Machine
> platform.
>
> ...
>
> --- a/include/linux/page-flags.h
> +++ b/include/linux/page-flags.h
> @@ -928,6 +928,14 @@ static inline bool is_page_hwpoison(struct page *page)
> #define PG_offline 0x00000100
> #define PG_table 0x00000200
> #define PG_guard 0x00000400
> +#define PG_unaccepted 0x00000800

"For pages that are never mapped to userspace (and aren't PageSlab),
page_type may be used."

Is that true of these pages?