Re: [RFC PATCH] efivarfs: Introduce efivarfs refresh remount

[Weizhao Ouyang]

On Wed, Jan 15, 2025 at 10:34 PM James Bottomley
<James.Bottomley@xxxxxxxxxxxxxxxxxxxxx> wrote:
>
> On Wed, 2025-01-15 at 22:14 +0800, Weizhao Ouyang wrote:
> > Currently, when setting efi variables through the runtime service,
> > efivarfs cannot sync variable updates properly. Introduce efivarfs
> > refresh remount to support efivarfs information updates from other
> > sources.
>
> What other sources could there possibly be?  While the Linux kernel has
> sole possession of the EFI RT interface after ExitBootServices has been
> called, nothing else should be able to update the variables except
> efivarfs.  This is a guarantee from UEFI so why do you think we can't
> rely on it?

One route that may exist is: drivers/firmware/efi/test/efi_test.c holds
some ioctls to call runtime service.

BR,
Weizhao

>
> Regards,
>
> James
>