Comment # 15 on bug 1156441 from Ignaz Forster

(In reply to Michael Chang from comment #14)
> (In reply to Ignaz Forster from comment #12)
> > FYI: Setting the values in the env_block will work on a read-only root file
> > system, I tested that and it's currently in production ;-) The disadvantage
> > is that the command will still return with an error message, as the grubenv
> > file could not be modified, that's why I wanted to introduce the
> > /boot/writable subvolume.
> 
> This also made me confused, as the writable /boot/writable seems to be
> enough to overcome the ro snapshot that grubenv with $env_block could be
> directly created on. What's the reason it's not proceeded ?

>From what I understand $env_block is only written when using
/boot/grub/grubenv, but not other files according to line 442 in
https://build.opensuse.org/package/view_file/Base:System/grub2/grub2-grubenv-in-btrfs-header.patch?expand=1.