[PATCH 10/16] efi_loader: UEFI variable persistence

Punit Agrawal
2020-03-30T10:03:27Z

Heinrich Schuchardt <xypron.glpk@gmx.de> writes:

> On 3/27/20 9:07 AM, Punit Agrawal wrote:
>> Heinrich Schuchardt <xypron.glpk@gmx.de> writes:
>>
>>> Persist non-volatile UEFI variables in a file on the EFI system partition.
>>>
>>> The file is written:
>>>
>>> * whenever a non-volatile UEFI variable is changed after initialization
>>> of the UEFI sub-system.
>>> * upon ExitBootServices()
>>
>> I might be missing something but how does this cope with the ESP being
>> on a storage medium access to which is owned by the OS at runtime? e.g.,
>> partition on eMMC or SATA drive.
>
> This development does not guard against manipulation by the OS.
>
> Ilias is cureently working on a solution for ATF based devices that will
> provide secure storage for variables.

Thanks for the clarification.

So the current patches are more RFC material - as it would be worth
seeing the whole picture before things start getting baked in.

I only recently started looking at EFI features in u-boot and am trying
to piece the story together based on the patches in-flight.

Thanks,
Punit …