Bug#956131: [live-build] boot failure, broken bootloaders when not using syslinux

[jnqnfe@gmail.com]

Hi,

Okay, so I've just take a cursory look at your liveid stuff which also
led me to #924053 where you've already brought up the EFI failure side
of things.

I'll limit my response here (this bug report discussion) to matters
relating to simply fixing the broken ability to get bootable images;
discussion of a unique-disc identification solution can take place
separately.

To fix the issue of broken EFI booting when syslinux is not used (and
thus binary_syslinux was not put in place /live/vmlinuz), I was
intending to solve by moving creation of short filename kernel files
out of binary_syslinux into somewhere common.

The first problem with this though is that alone of course it is not
enough because it does not cover the `/live/vmlinuz1` multi-flavour
case, so a change to binaru_grub-efi would also be needed in order to
dynamically change the searched for file to /live/vmlinuz1 where
appropriate.

However, I now understand from reading #924053 that although this would
fix things in all/most cases, it's at risk of breaking for odd
situations like your HP laptop case. Using /.disc/info as the searched
for file as proposed in #924053 is much a better solution.

My current intention is to take the patch of yours provided in #924053
that makes this change, though with a tweaked commit message (I think
the problem is EFI specific not Secure Boot specific), and submit it in
an MR, along with the fix for grub-pc, and some additional loosely
related work, in one or more MRs.

While the concept of correctly identifying discs (aka liveid type
stuff) is interesting and of some potential value, priority should be
given to simply fixing the ability to create working images first and
foremost.

I will have the patches mark this bug and #924053 as closed, and leave
you to create a new wishlist bug to propose or re-start discussion of
the unique-disc identification stuff as you wish.

Regards,
Lyndon

On Wed, 2020-04-08 at 09:40 +0200, adrian15sgd wrote:
> I think what you need is liveid.
> 
> https://github.com/rescatux/liveid
> 
> Here you can find the technical details and commits:
> 
> https://github.com/rescatux/liveid/blob/master/LIVEID_LIVE_BUILD_IMPLEMENTATION_1.md
> 
> That way you won't longer depend on arbitrary files such as vmlinuz.
> 
> 
> Feedback is welcome.
> 
> 
> P.S.: I was going to do proper merge requests in about 5 or 6 months 
> later but here you are.
> 
> adrian15
> 
> 
> El 8/4/20 a las 1:02, jnqnfe@gmail.com escribió:
> > update:
> > 
> > 1) from my notes, in fact I'd gone back as far as v5.0 confirming
> > the
> > presence of the grub-pc failure.
> > 
> > 2) I've noticed the presence of the fixed path '/live/vmlinuz' in
> > binary_grub-efi, and with a hack to have this replaced with the
> > long
> > name '/live/vmlinuz-4.19.0-8-amd64' this also fixes the EFI side of
> > the
> > problem, so that explains how the EFI stuff ends up checking that
> > fixed
> > /live/vmlinuz' path and presents an alternate opportunity for a
> > fix. It
> > seems the author of the EFI live-build functionality only tested it
> > with syslinux.
> >