Re: [PATCH v2 0/7] re-fork wic pcbios and efi plugins

[Henning Schild <henning.schild@siemens.com>]

Am Mon, 6 Sep 2021 07:05:17 +0200
schrieb Jan Kiszka <jan.kiszka@siemens.com>:

> On 03.09.21 14:53, Henning Schild wrote:
> > changes since v1:
> >   - efi plugin forked as well
> >   - systemd-boot support in efi plugin enabled
> >   - common functionality in utility library
> >   - test case for system-boot
> >   - "cp -a" moved to "find exec cp" because of ubuntu
> >   - changed wks files to exclude boot from root and mount it
> > 
> > The forked plugins have gotten out of sync with the last wic version
> > bumps. And the original fork was not exactly minimal or made for
> > easy maintenance.
> > 
> > This series does a re-fork of the two plugins with the aim to come
> > up with something readable, minimal and maintainable.
> >   
> 
> I already pointed this out to Baurzhan: We should create some
> developer doc somewhere that list the update procedures for forked
> elements. Which files come from upstream? Which are supposed to be
> vanilla? Which contain changes and should be revisited when upstream
> is updated? With such a file, both maintainers and contributors can
> check what to do when the want to update affected files / components
> or see patches touching them.
> 
> Maybe start that file with covering wic and its plugins?

This is a good idea but i would not want to include a patch into this
series. Something to do on top.
The main reason is that we also have half-forked bits like the wks
files and especially meta/classes/wic-img.bbclass which probably has
not been checked in a long time. 

> > There used to be a special case for grub-efi where the actual
> > kernel and initrd would remain in the root partition, which kind of
> > allowed kernel updates with apt-get. Now all three bootloaders
> > (systemd-boot now works as well) place bootloader, config and boot
> > artifacts in a boot-partition.
> > 
> > Kernel updates with apt-get are now consistantly "broken". That
> > consistency very likely is not too bad. A generic solution for this
> > feature (if wanted) will need to be found. Covering not just these
> > three bootloaders but possibly also u-boot and efibootguard.  
> 
> I assume that this only applies to efi and pcbios images, not
> u-boot-script or anything else that manages kernel updates more or
> less properly already.

Right. The u-boot plugin is not a fork but our own. It might contain
copied bits but i did not look at it at all. And it is currently the
only bootloader bringing an update-script to generate bootloader conf
when updating the kernel with apt-get.

At a later point we can see if we can enable "apt-get update <kernel>"
bootloader indep. I think that should be possible very similar to how
we do things for u-boot.

But that is a story for the future, after this series has been merged.
I see it as a win to move from "mostly broken" to "consistently
broken". The only case that sometimes worked was grub ... depending on
which wic version and whether one would mount <boot> at /boot.

Henning

> Jan
>