Re: [PATCH 2/5] efi/x86: Implement support for unaccepted memory

[Dave Hansen]

On 8/9/21 11:26 PM, Kirill A. Shutemov wrote:
> +config UNACCEPTED_MEMORY
> +	bool
> +	depends on EFI_STUB
> +	help
> +	   Some Virtual Machine platforms, such as Intel TDX, introduce
> +	   the concept of memory acceptance, requiring memory to be accepted
> +	   before it can be used by the guest. This protects against a class of
> +	   attacks by the virtual machine platform.
> +
> +	   This option adds support for unaccepted memory and makes such memory
> +	   usable by kernel.

Do we really need a full-blown user-visible option here?  If we, for
instance, just did:

config UNACCEPTED_MEMORY
	bool
	depends on EFI_STUB

it could be 'select'ed from the TDX Kconfig and no users would ever be
bothered with it.  Would a user *ever* turn this on if they don't have
TDX (or equivalent)?