Re: [PATCH v3 2/3] efi: Reserve confidential computing secret area

From: Greg KH
Date: Thu Oct 14 2021 - 09:36:31 EST


On Thu, Oct 14, 2021 at 01:08:47PM +0000, Dov Murik wrote:
> When efi-stub copies an EFI-provided confidential computing (coco)
> secret area, reserve that memory block for future use within the kernel.
>
> Signed-off-by: Dov Murik <dovmurik@xxxxxxxxxxxxx>
> ---
> arch/x86/platform/efi/efi.c | 1 +
> drivers/firmware/efi/Makefile | 2 +-
> drivers/firmware/efi/coco.c | 41 +++++++++++++++++++++++++++++++++++
> drivers/firmware/efi/efi.c | 4 ++++
> include/linux/efi.h | 3 +++
> 5 files changed, 50 insertions(+), 1 deletion(-)
> create mode 100644 drivers/firmware/efi/coco.c
>
> diff --git a/arch/x86/platform/efi/efi.c b/arch/x86/platform/efi/efi.c
> index 147c30a81f15..35e082e5f603 100644
> --- a/arch/x86/platform/efi/efi.c
> +++ b/arch/x86/platform/efi/efi.c
> @@ -93,6 +93,7 @@ static const unsigned long * const efi_tables[] = {
> #ifdef CONFIG_LOAD_UEFI_KEYS
> &efi.mokvar_table,
> #endif
> + &efi.coco_secret,

Shouldn't this depend on CONFIG_EFI_SECRET?

Why build all of this code if that option is not enabled?

thanks,

greg k-h