Re: [PATCH 05/16] efi: Add EFI_SECURE_BOOT bit

[Josh Boyer]

On Thu, Nov 17, 2016 at 4:58 PM, Ard Biesheuvel
<ard.biesheuvel@xxxxxxxxxx> wrote:
> On 16 November 2016 at 21:47, David Howells <dhowells@xxxxxxxxxx> wrote:
>> From: Josh Boyer <jwboyer@xxxxxxxxxxxxxxxxx>
>>
>> UEFI machines can be booted in Secure Boot mode.  Add a EFI_SECURE_BOOT bit
>> for use with efi_enabled.
>>
>> Signed-off-by: Josh Boyer <jwboyer@xxxxxxxxxxxxxxxxx>
>> Signed-off-by: David Howells <dhowells@xxxxxxxxxx>
>> ---
>>
>>  arch/x86/kernel/setup.c |    1 +
>>  include/linux/efi.h     |    1 +
>>  2 files changed, 2 insertions(+)
>>
>> diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c
>> index 9521acce8378..539f29587712 100644
>> --- a/arch/x86/kernel/setup.c
>> +++ b/arch/x86/kernel/setup.c
>> @@ -1164,6 +1164,7 @@ void __init setup_arch(char **cmdline_p)
>>         if (boot_params.secure_boot &&
>>             IS_ENABLED(CONFIG_EFI_SECURE_BOOT_LOCK_DOWN)) {
>>                 lock_kernel_down();
>> +               set_bit(EFI_SECURE_BOOT, &efi.flags);
>
> Why is this x86 only? And why is this bit only set if

Because it was initially written like 3 years ago before ARM even had
UEFI.  Needs a refresh.

> CONFIG_EFI_SECURE_BOOT_LOCK_DOWN is enabled?

That part is new and something David added.  Probably not necessary.

josh