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Re: GPT attributes in dkwedge [PATCH]



    Date:        Mon, 25 Sep 2023 09:45:25 -0000 (UTC)
    From:        mlelstv%serpens.de@localhost (Michael van Elst)
    Message-ID:  <uerkrk$80f$1%serpens.de@localhost>

  | There can be multiple EFI system partitions on a drive,

That was my understanding from reading the spec.

  | but it sometimes confuses software,

What can I say to that...

  | some boot procedures will only handle the first ESP.

See my reply to RVP's reply just below.

  | But you "should" be able to select an ESP in UEFI just like you would
  | select a boot device in BIOS.

There's no problem picking the correct ESP from which to load efibootx64.efi
(or whatever the magic name is) - that part works fine, and if I have multiple
ESPs with NetBSD's efiboot in them I can pick whichever one I want (I think,
which probably gives me another option for testing updated efiboot code).

It is just boot.cfg which is giving problems.

rvp%SDF.ORG@localhost said:
  | The first EFI partition. Without a bootme etc., flag, the NetBSD UEFI
  | bootloader tries to read /EFI/NetBSD/boot.cfg from there, first. 

I wondered about that when I saw Edgar's first message earlier, it
suddenly occurred to me that I normally never go near that ESP (that one
was set up by the system builders to boot wintrash - a subject which has
no interest to me, but I have retained intact (just reduced the size of the
wintrash partition) so it can be used for repairs, which I suspect is what
just happened.

So, I went and checked, but it turns out that I was (apparently) very
thorough when I was scattering boot.cfg files around, I discovered that
I have:

	./EFI/Boot/boot.cfg
	./EFI/NetBSD/boot.cfg
	./EFI/boot.cfg
	./boot.cfg

(that is relative to /mnt where I briefly temporarily mounted that parition).

None of those are used...  (there's no NetBSD boot code there, EFI/Boot
is a wintrash boot directory, but the boot.cfg file doesn't seem to bother 
that).

  | I've hacked my bootloader locally to make it try a /EFI/NetBSD/boot.cfg on
  | the partition where it itself was loaded from

I'd suggest that's what it should always attempt first, absent other info,
rather than being a local hack for you.

kre



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