Re: [PATCHv11 6/9] efi/unaccepted: Avoid load_unaligned_zeropad() stepping into unaccepted memory

[Dave Hansen]

On 5/16/23 11:08, Ard Biesheuvel wrote:
>> But, this approach does not work for unaccepted memory. For TDX, a load
>> from unaccepted memory will not lead to a recoverable exception within
>> the guest. The guest will exit to the VMM where the only recourse is to
>> terminate the guest.
>>
> Does this mean that the kernel maps memory before accepting it? As
> otherwise, I would assume that such an access would page fault inside
> the guest before triggering an exception related to the unaccepted
> state.

Yes, the kernel maps memory before accepting it (modulo things like
DEBUG_PAGEALLOC).