Re: [PATCH] efi: x86/xen: switch to efi_get_secureboot_mode helper

[boris.ostrovsky@xxxxxxxxxx]

On 11/4/20 5:14 PM, Ard Biesheuvel wrote:
> Now that we have a static inline helper to discover the platform's secure
> boot mode that can be shared between the EFI stub and the kernel proper,
> switch to it, and drop some comments about keeping them in sync manually.
>
> Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
> ---
>  arch/x86/xen/efi.c                        | 37 +++++---------------
>  drivers/firmware/efi/libstub/secureboot.c |  3 --
>  2 files changed, 9 insertions(+), 31 deletions(-)
>
> diff --git a/arch/x86/xen/efi.c b/arch/x86/xen/efi.c
> index 205a9bc981b0..a27444acaf1e 100644
> --- a/arch/x86/xen/efi.c
> +++ b/arch/x86/xen/efi.c
> @@ -93,37 +93,22 @@ static efi_system_table_t __init *xen_efi_probe(void)
>  
>  /*
>   * Determine whether we're in secure boot mode.
> - *
> - * Please keep the logic in sync with
> - * drivers/firmware/efi/libstub/secureboot.c:efi_get_secureboot().
>   */
>  static enum efi_secureboot_mode xen_efi_get_secureboot(void)
>  {
> -     static efi_guid_t efi_variable_guid = EFI_GLOBAL_VARIABLE_GUID;
>       static efi_guid_t shim_guid = EFI_SHIM_LOCK_GUID;
> +     enum efi_secureboot_mode mode;
>       efi_status_t status;
> -     u8 moksbstate, secboot, setupmode;
> +     u8 moksbstate;
>       unsigned long size;
>  
> -     size = sizeof(secboot);
> -     status = efi.get_variable(L"SecureBoot", &efi_variable_guid,
> -                               NULL, &size, &secboot);
> -
> -     if (status == EFI_NOT_FOUND)
> -             return efi_secureboot_mode_disabled;
> -
> -     if (status != EFI_SUCCESS)
> -             goto out_efi_err;
> -
> -     size = sizeof(setupmode);
> -     status = efi.get_variable(L"SetupMode", &efi_variable_guid,
> -                               NULL, &size, &setupmode);
> -
> -     if (status != EFI_SUCCESS)
> -             goto out_efi_err;
> -
> -     if (secboot == 0 || setupmode == 1)
> -             return efi_secureboot_mode_disabled;
> +     mode = efi_get_secureboot_mode(efi.get_variable);


Which tree is this patch against? I don't see a definition of 
efi_get_secureboot_mode().


> +     if (mode == efi_secureboot_mode_unknown) {
> +             efi_err("Could not determine UEFI Secure Boot status.\n");


We need to include drivers/firmware/efi/libstub/efistub.h for that. Which I am 
not sure is meant to be included anywhere outside of libstub.


-boris