diskimage-builder/diskimage_builder
Ian Wienand 2d47d4157c Fix BLS based bootloader installation
This reverts I2701260d54cf6bc79f1ac765b512d99d799e8c43,
Idf2a471453c5490d927979fb97aa916418172153 and part of
Iecf7f7e4c992bb23437b6461cdd04cdca96aafa6 which added special flags to
update kernels via grubby.

These changes actually ended up reverting the behaviour on Fedora 35,
which is what led me to investigate what was going on more fully.

All distros still support setting GRUB_DEVICE in /etc/default/grub;
even the BLS based ones (i.e. everything !centos7).

The implementation *is* confusing -- in earlier distros each BLS entry
would refer to the variable $kernelopts; which grub2-mkconfig would
write into /boot/grub2/grubenv.  After commit [1] this was reverted,
and the kernel options are directly written into the BLS entry.

But the real problem is this bit from [2]

 get_sorted_bls()
 {
     if ! [ -d "${blsdir}" ] || ! [ -e /etc/machine-id ]; then
        return
     fi
     ...
     files=($(for bls in ${blsdir}/${machine_id}-*.conf; do
     ...
 }

i.e., to avoid overwriting BLS entries for other OS-boots (?),
grub2-mkconfig will only update those BLS entries that match the
current machine-id.

The problem for DIB is that we are clearing the machine-id early in
finalise.d/01-clear-machine-id, but then running the bootloader update
later in finalise.d/50-bootloader.

The result is that the bootloader entry generated when we installed
the kernel (which guessed at the root= device, etc.) is *not* updated.
Even more annoyingly, the gate doesn't pick this up -- because the
gate tests run on a DIB image that was booted with
"root=LABEL=cloudimg-rootfs" the kernel initially installed with
"install-kernel" (that we never updated) is actually correct.  But
this fails when built on a production host.

Thus we don't need any of the explicit grubby updates; these are
reverted here.  This moves the machine-id clearing to after the
bootloader setup, which allows grub2-mkconfig to setup the BLS entries
correctly.

[1] 4a742183a3
[2] https://src.fedoraproject.org/rpms/grub2/blob/rawhide/f/0062-Add-BLS-support-to-grub-mkconfig.patch

Depends-On: https://review.opendev.org/c/zuul/nodepool/+/818705
Change-Id: Ia0e49980eb50eae29a5377d24ef0b31e4d78d346
2021-11-25 14:26:23 +11:00
..
block_device Replace deprecated import of ABCs from collections 2021-07-17 01:02:19 +09:00
elements Fix BLS based bootloader installation 2021-11-25 14:26:23 +11:00
lib Merge "Add element block-device-efi-lvm" 2021-07-08 01:08:26 +00:00
tests Switch from unittest2 compat methods to Python 3.x methods 2020-07-07 11:11:28 +08:00
__init__.py Bump hacking to 0.9.x series 2014-07-21 10:15:41 +02:00
disk_image_create.py Remove virtualenv activation 2020-06-11 16:49:15 +10:00
element_dependencies.py Uncap hacking 2020-02-24 10:34:46 +11:00
logging_config.py Add timestamp output filter 2017-06-16 15:58:50 +10:00
paths.py Move diskimage-image-create to an entry point 2016-11-02 05:12:11 +00:00
version.py Create docs site containing element READMEs 2015-02-10 11:45:35 -08:00