Re: efivarfs fails with `No such device` when EFI runtime is missing

[Paul Menzel]

[Use Ard’s current email, and add other maintainers]

Am 11.05.21 um 22:55 schrieb Paul Menzel:
> Dear Linux folks,
>
>
> I migrated a 32-bit GNU/Linux installation from BIOS to EFI. Trying to 
> edit the entries in UEFI’s Boot Manager with `efibootmgr`, I got the error:
>
>     EFI variables are not supported on this system
>
> `sudo modprobe efivarfs` fails with
>
>     No such device
>
> After several tries, I found
>
>     [    0.000000] efi: No EFI runtime due to 32/64-bit mismatch with 
> kernel
>
> logged by Linux, and then I found the Stack Overflow thread *How could 
> 32bit kernel read efivars from 64bit UEFI?* [1].
>
> I would have thought, setting EFI variables is just directly writing to 
> some storage. But probably not.
>
> Could the error message for the efivarfs load failure be improved, that 
> *device* means the runtime service (if I am not mistaken)?
>
>
> Kind regards,
>
> Paul
>
>
> [1]: https://stackoverflow.com/questions/46610442/how-could-32bit-kernel-read-efivars-from-64bit-uefi