Re: [PATCH v2, RESEND] x86/efi: Safely enable unaccepted memory in UEFI

[Dave Hansen]

On 1/31/23 08:08, Dionna Amalie Glaze wrote:
>>> +       efi_status_t status;
>>> +
>>> +       if (!IS_ENABLED(CONFIG_UNACCEPTED_MEMORY))
>> Do we need to check for IS_ENABLED(CONFIG_AMD_MEM_ENCRYPT) here as well?
>>
> Arguably no, since the firmware should only make the protocol
> available when it determines that the protocol should be used. In our
> case, that's just SEV-SNP. The firmware's TDX logic will not expose
> this protocol.
> 
> This maintains flexibility for the rare case that the TDX go-to-market
> schedule doesn't align with upstream's acceptance of unaccepted memory
> support, but does accept the generic TDX support. Best not paint
> ourselves into a corner.

Yes, please.  Maintaining this functionality for TDX would provide some
more flexibility in how things get accepted upstream.