Re: [PATCH v7 18/36] x86/efi: Update EFI pagetable creation to work with SME

From: Matt Fleming
Date: Thu Jun 22 2017 - 06:58:39 EST


On Fri, 16 Jun, at 01:53:17PM, Tom Lendacky wrote:
> When SME is active, pagetable entries created for EFI need to have the
> encryption mask set as necessary.
>
> When the new pagetable pages are allocated they are mapped encrypted. So,
> update the efi_pgt value that will be used in cr3 to include the encryption
> mask so that the PGD table can be read successfully. The pagetable mapping
> as well as the kernel are also added to the pagetable mapping as encrypted.
> All other EFI mappings are mapped decrypted (tables, etc.).
>
> Reviewed-by: Borislav Petkov <bp@xxxxxxx>
> Signed-off-by: Tom Lendacky <thomas.lendacky@xxxxxxx>
> ---
> arch/x86/platform/efi/efi_64.c | 15 +++++++++++----
> 1 file changed, 11 insertions(+), 4 deletions(-)

Reviewed-by: Matt Fleming <matt@xxxxxxxxxxxxxxxxxxx>