feat(grubby): provide the /etc/sysconfig/kernel file

[ddstreet]

This file has a setting, UPDATEDEFAULT=, which is used by the kernel-install (aka installkernel) program to determine if the default kernel should be updated to use the newly installed kernel.

This sets UPDATEDEFAULT=yes, so a newly installed kernel will be set as the default kernel (on the next boot); without this, the default kernel will remain set to the current kernel.

Taken from upstream:
https://src.fedoraproject.org/rpms/grubby/c/482a2825c47c4fd28a18beb279a3e826461bf878

Fixes: AB#20392

[Copilot]

Pull request overview

Note

Copilot was unable to run its full agentic suite in this review.

Adds an /etc/sysconfig/kernel configuration file to the grubby package/component so kernel-install can set defaults consistently.

Changes:

• Add a kernel.sysconfig file defining UPDATEDEFAULT and DEFAULTKERNEL.
• Update grubby.spec to ship /etc/sysconfig/kernel as %config(noreplace).
• Add a grubby component overlay definition (and adjust component indexing/lock fingerprint).

Reviewed changes

Copilot reviewed 5 out of 6 changed files in this pull request and generated 4 comments.

Show a summary per file

File	Description
specs/g/grubby/kernel.sysconfig	Adds the sysconfig file content to be shipped with the RPM.
specs/g/grubby/grubby.spec	Adds Source999, installs the sysconfig file, and marks it as config.
locks/grubby.lock	Updates input fingerprint to reflect content changes.
base/comps/grubby/kernel.sysconfig	Adds the same sysconfig file content for the component overlay system.
base/comps/grubby/grubby.comp.toml	Defines overlays to add the sysconfig file and patch the spec.
base/comps/components.toml	Removes the components.grubby entry from the central component list.

[ddstreet]

verified this does fix the kernel default update behavior:

verifying issue exists, on a fresh install of azl4 beta from marketplace:

$ sudo grubby --default-kernel
/boot/vmlinuz-6.18.29-1.1.azl4.x86_64
$ sudo dnf update -y
...(updates kernel)...
$ sudo grubby --default-kernel
/boot/vmlinuz-6.18.29-1.1.azl4.x86_64
$ sudo reboot
...(reboots)...
$ uname -r
6.18.29-1.1.azl4.x86_64

verifying issue fixed, on a fresh install of azl4 beta from marketplace:

(First, scp patched grubby rpm to system)

$ sudo grubby --default-kernel
/boot/vmlinuz-6.18.29-1.1.azl4.x86_64
$ sudo dnf install ./grubby-8.40-87.azl4.x86_64.rpm
$ sudo dnf update -y
...(updates kernel)...
$ sudo grubby --default-kernel
/boot/vmlinuz-6.18.31-1.3.azl4.x86_64
$ sudo reboot
...(reboots)...
$ uname -r
6.18.31-1.3.azl4.x86_64

[ddstreet]

closing this in favor of updating grubby to f44 version with this change