Subject: [bug#26339] "extlinux", "extlinux" gpt, bootloader-configuration without package nor installer

From: Danny Milosavljevic <[email-masked]>
Date: Tue, 13 Jun 2017 07:07:11 +0200

Hi Ludo,

On Mon, 12 Jun 2017 22:20:54 +0200
[email-masked] (Ludovic Courtès) wrote:

> If “extlinux” is just the name of the configuration file format, 

It depends.

Syslinux-the-website thinks extlinux is the entire bootloader.

And https://fedoraproject.org//wiki/Changes/u-boot_syslinux which is a tracking page for adding support for extlinux.conf to u-boot (back then) says "syslinux style configuration files".

So we can also keep it as Mathieu intended and just overwrite the installer for u-boot.  Looks good to me.

>Given that the configuration file syntax is similar but presumably not identical (?) 

u-boot doesn't support the entire format.  For example it can't currently do submenus.  But the idea with the above Fedora change was to use the same extlinux.conf for ARM and x86_64.  No idea whether they are actually using a subset still.

>and that it’s fairly simple, it may be best to simply have
>both ‘extlinux-configuration-file’ and ‘u-boot-configuration-file’.
>It’s a case where factorization is probably a bad idea.

After looking into it some more, I'm fine with any of the ways to proceed and defer the decision to Mathieu.

At first I thought it would be clearer if we had the extlinux.conf file writer common (also PXEboot and other things use it in the wild) - but it's not that bad to duplicated it.  Maybe a little opaque and the different writers would probably diverge on accident as we added features - but if we were careful it would be OK.