Following FLUSP tutorial “Building and booting a custom Linux kernel for ARM using kw”

It took me some time, but eventually this tutorial clicked into place and I got a better understanding of how things were related.

First things first: installing kw.

During the installation, I had to make a small adjustment to the dependency tracker. In kw/documentation/dependencies/arch.dependencies, I updated the script to recognize pipewire-pulse as a valid dependency instead of pulseaudio. This is due to Pipewire being the default on my Manjaro system.

Once kw was installed, I needed to adjust the kw remote command to play nicely with the custom port forwarding network tweak I set up in the previous tutorial:

kw remote --add arm64 root@127.0.0.1:2222 --set-default

(Note: I also had to run sudo apt install rsync inside the VM, as kw relies on it for fast file transfers).

Booting the VM

I spent some hours trying to get my newly compiled kernel to actually boot on my VM. Initially, it would just hang without sending any information to the console. I don’t quite get what happened, but I decided to redo the steps from this tutorial from scratch and eventually things started to work.

On this second run, things started to make more sense and I think I got a better understanding of the overall compilation architecture. The hardest part for me was connecting the dots between:

• What the .config file does.
• What is actually being compiled when you run kw build.
• The difference between what gets compiled as a loadable .ko module vs. what gets baked directly into the main Kernel Image.