Draft Development Dockerfile

[julianrubisch]

Good morning!

I thought I'd spike the creation of a Dockerfile which might or might not be useful for local development. (It is possible to use the local sound device as a passthrough, I've explored this here a while ago.)

The build command is

docker buildx build -t ubuntu-avb . 

Currently I'm stuck at the modprobe step, which needs privileged access to run. But even if I run the container manually (docker run --rm -ti --privileged ubuntu-avb) and try to load the module, I get:

# modprobe -S $KVERSION snd-avb
modprobe: ERROR: could not insert 'snd_avb': Exec format error

dmesg output:

[47018.397452] module soundcore: .gnu.linkonce.this_module section size must match the kernel's built struct module size at run time

This might have to do with the following warning during make:

Skipping BTF generation for /linux-avb-driver/snd-avb.ko due to unavailability of vmlinux

Which is probably due to the use of linux-virtual headers. So it might not be possible after all...

[julianrubisch]

Note: Apparently running modprobe in a CMD on container boot is the way to go, but I can't get past the Exec format error for now

[grrrr]

Not sure what the problem is, but passing KVERSION to make should not be necessary if one is building for the running kernel. Exec error could be an architecture or kernel version mismatch.

[grrrr]

By the way, i have CI running on the gitlab server which mirrors the github project, and vice versa.

[julianrubisch]

Not sure what the problem is, but passing KVERSION to make should not be necessary if one is building for the running kernel. Exec error could be an architecture or kernel version mismatch.

yeah the problem is that $(uname -r) will output the kernel version of the host system, which in my case is orbstack. using linux-virtual under linuxkit is actually the way it's supposed to work, but I guess I'm pushing the boundaries here.

Anyway, not a real problem, I just pondered how I'd go about setting up a minimal local dev environment. I'll keep working on this when I have time.

[grrrr]

Btw, out of interest, i read this article on kernel modules in Docker.
Obviously, the modules are not isolated in the Docker environment. In this case, why use Docker at all?