Add example for kernel replacement

[plata]

I'm trying to use the linux-surface kernel.

In a VM, the following works:

sudo wget -O /etc/yum.repos.d/linux-surface.repo \
    https://pkg.surfacelinux.com/fedora/linux-surface.repo
wget https://github.com/linux-surface/linux-surface/releases/download/silverblue-20201215-1/kernel-20201215-1.x86_64.rpm
rpm-ostree override replace ./*.rpm

see linux-surface/linux-surface#1128

However, in the Containerfile:

RUN wget -O /etc/yum.repos.d/linux-surface.repo https://pkg.surfacelinux.com/fedora/linux-surface.repo && \
    wget https://github.com/linux-surface/linux-surface/releases/download/silverblue-20201215-1/kernel-20201215-1.x86_64.rpm  && \
    rpm-ostree override replace ./*.rpm && \
    rpm-ostree install surface-secureboot

This shows an error when generating initramfs during the build. Interestingly, the build still succeeds but after rebasing to the image, it boots with kernel panic.

The error:

dracut: No '/dev/log' or 'logger' included for syslog logging
dracut: Executing: /usr/libexec/rpm-ostree/wrapped/dracut --no-hostonly --kver 6.2.13-1.surface.fc38.x86_64 --reproducible -v --add ostree -f /tmp/.tmpOqYwdG/initramfs.img
dracut: /lib/modules/6.2.13-1.surface.fc38.x86_64//modules.dep is missing. Did you run depmod?
error: rpm-ostree kernel-install wrapper: Running dracut: Failed to generate initramfs (via dracut) for for kernel: 6.2.13-1.surface.fc38.x86_64: ExitStatus(unix_wait_status(256))

I tried to follow https://github.com/coreos/layering-examples/blob/main/replace-kernel/Containerfile but it gives the same issue.

RUN rpm-ostree override replace https://github.com/linux-surface/linux-surface/releases/download/fedora-38-6.2.13-1/kernel-surface-6.2.13-1.fc38.x86_64.rpm \
                                https://github.com/linux-surface/linux-surface/releases/download/fedora-38-6.2.13-1/kernel-surface-devel-6.2.13-1.fc38.x86_64.rpm

I don't think that this is specific to that kernel, so having some guideline on how to replace the kernel would be greatly appreciated.

[plata]

When following the surface-linux guide, I get

error: Could not depsolve transaction; 1 problem detected:
 Problem: package kernel-devel-matched-6.2.15-300.fc38.x86_64 from @System requires kernel-core = 6.2.15-300.fc38, but none of the providers can be installed
  - conflicting requests

This doesn't happen with base quay.io/fedora-ostree-desktops/kinoite. What's the difference in ublue?

[xynydev]

uBlue adds kernel modules, could that be it? I recommend also asking on Discord with the others.

[KE0VVT]

I used JosSamLoh's script to replace the kernel, but it did not work.

[plata]

That looks pretty similar to what I tried without success as well.

[xynydev]

Closing this issue now. Future efforts towards documentation for kernel replacement in images based on uBlue should be done under ublue-os/website, specifically added under an "Advanced" section in the Tinkerer's guide. In the meanwhile, discuss here https://github.com/orgs/ublue-os/discussions/169

[plata]

See https://github.com/ublue-os/surface/blob/04f10b17d13503dab2b737bebdfe63f5c6a84788/Containerfile#L19.

[plata]

I've copied the commands but it still doesn't work. Could it be that startingpoint behaves differently?

[xynydev]

I've copied the commands but it still doesn't work. Could it be that startingpoint behaves differently?

Are you basing on an image with kmods?

[plata]

Not quite sure: I based on ghcr.io/ublue-os/kinoite-main:38 should that have kmods?

[xynydev]

Yeah, I think that should be fine. There's no reason this shouldn't work AFAIK, so it just depends on diagnosing what kinda errors you're getting.

[plata]

After looking at the surface workflow and the changes to kmods, my understanding is that I must use *-nokmods for < 39 and *-main for >= 39.