Re: RFC: A partition for grubenv, etc.

[Chris Murphy]

On Thu, May 27, 2021 at 2:59 AM Michael Chang <mchang@suse.com> wrote:
>
> On Wed, May 26, 2021 at 08:36:05PM -0600, Chris Murphy wrote:
> > So is the next era going to be we recommend /boot on FAT?
>
> No. I meant a new partition type only for grubenv files and keep
> everything else as is. The filesystem can be extX or FAT whichever is
> writable by grub.  For efi, we probably don't need to define new
> partition, as we can reuse the efi system partition.

Or use the same partition for consistency instead of yet another exception?

But also, GRUB strictly speaking doesn't write to any file system.
It's overwriting a sector or two, no file system metadata is updated,
hence the problem.

> It is easier to handle in script as we only need to point to the new
> writable location if available, the concern to admin is that we also
> have to define mount point for linux (eg /boot/grubenv).

That'd be three partitions needed by BIOS GRUB: BIOS Boot, grubenv,
and /boot. Plus ~440 bytes on LBA 0, quasi-partition. Seems like a
lot.

What about a FAT formatted file system at /boot/grub and everything
just lives there? Deprecate BIOS Boot, use blocklists instead. Grubenv
partition proposal isn't needed, it can just stay where it is,
unchanged and can be reliably written to. And whether UEFI or BIOS,
grub looks to /boot/grub/ for all modules and configuration files?



-- 
Chris Murphy