Re: GPT attributes in dkwedge [PATCH]

[Martin Husemann <martin%duskware.de@localhost>]

On Sun, Sep 24, 2023 at 05:41:30PM +0000, Taylor R Campbell wrote:
> The documentation in gpt(8) needs to be clarified -- and I'm not sure
> there's any other canonical reference about it in any of our
> documentation -- but it sounds to me like it is supposed to be:
> 
> (a) where NetBSD's efiboot finds the kernel, and/or
> (b) what root partition the kernel will use.
> 
> It's not clear what else the bootme flag would be for, and it seems
> that unless boot.cfg instructs the bootloader to pass a different root
> device to the kernel with the `root' command, the same partition that
> was used to find the kernel is a reasonable default choice of root
> device.
> 
> The bootme flag certainly not used to tell the machine firmware where
> to find efiboot -- it's is vendor-specific, a BSDism.

You are right. In my mental model it was always the GPT equivalent
of the MBR "active" flag - but that is not how the UEFI spec selects
the boot option firmware is going to boot.

To me the flag sounds totally useless and I'd say we should remove support
for it (or document it as only valid for compatibility with existing
setups).

What we need to fix instead is the full ability to set boot options from
inside NetBSD (and the install media) - with plain base system tools.
With that working and boot.cfg we have all the rope we need for whatever
complex boot scenarios we can imagine.

Martin