runvm # Calls QEMU with the necessary commands, uses sudo for enabling kvm
#### Inside QEMU
# insmod module/helloworld.ko # Load the kernel module
# rmmod module/helloworld.ko # Unload the module
#### C^A+X to exit
cd helloworld
bear -- make # generate the compile_commands.json
vim helloworld.c # Start editing!
# exit and then nix develop .# or just direnv reload
# to rebuild and update the runvm command
In order to do this in Nix a custom config file is generated, using a modified version of the configfile
derivation in the generic kernel builder, also known as the buildLinux function.
This was necessary as the default NixOS distribution defaults needed to be removed.
More documentation is inside the flake. A new package set called linuxDev is then added
as an overlay using linuxPackagesFor. The initial ram disk is built using the new make-initrd-ng.
It is called through its nix wrapper which safely copies the nix store packages needed over.
Busybox is included and the helloworld kernel module.
This is based on jordanisaacs flake, to get started with kernel modules.