bug#26339: [PATCH 02/18] system: Add extlinux support.

[Mathieu Othacehe]

Hi !

> So it should probably pick the current (not the newest) bootloader type.

I'm not fan of installing every bootloader config because it means
multiple gcroots and filling /boot with possibly useless stuff.

However, reading the "parameters" of current system, extracting
bootloader type, and reinstalling *only* the bootloader configuration
file for this type seems a good idea to me.

I'll use this solution for v4. Plus we can come up later with a more
intelligent solution, storing bootloader store path in "parameters" and
creating a gcroot for it.

Thanks,

Mathieu

2017-05-12 13:36 GMT+02:00 Ludovic Courtès <address@hidden>:

Hi,

Danny Milosavljevic <address@hidden> skribis:

> On Fri, 12 May 2017 10:26:53 +0200
> address@hidden (Ludovic Courtès) wrote:
>
>> > If there is a switch between extlinux and grub, the bootloader config file format (and name, too) will change.
>> >
>> > So if you do switch the config file out but don't switch the actual bootloader out it will not boot, right?
>>
>> Unless you regenerate the bootloader’s config file upon
>> ‘switch-configuration’.
>
> Yes, for the last-guix-installed bootloader (presumably the still-installed one).  Good point.
>
> That would mean only the bootloader type of the newest system generation would be checked - also when restoring older generations.
>
> Can the newest system generation be deleted?  Then eventually Guix could read the wrong bootloader type (of a bootloader which isn't actually installed at the time).

The newest generation can be deleted, but the current one cannot (it’s
possible that the current one is not the newest if you picked an old
entry in the boot menu.)

So it should probably pick the current (not the newest) bootloader type.

Ludo’.