Unable to access KVM kernel module when running QEMU-KVM about docker-github-actions-runner

[myoung34]

I'm not sure honestly. If I had to guess either the module isnt loaded or virtualization isnt enabled, but this is a bit outside the scope of the docker runner itself

[fabifont]

I've managed to resolve the problem by creating a custom image with qemu-kvm and dependencies, as well as updating the docker-compose.yaml file.

Here is the Dockerfile:

FROM myoung34/github-runner:latest

# Update packages and install qemu-kvm and dependencies
RUN apt-get update -y && \
    apt-get upgrade -y && \
    apt-get install -y qemu-kvm libvirt-daemon-system libvirt-clients bridge-utils && \
    apt-get clean && \
    rm -rf /var/lib/apt/lists/*

And here is the updated docker-compose.yaml:

version: "3.9"

services:
  my-worker:
    build:
      context: .
      dockerfile: Dockerfile
    privileged: true
    devices:
      - "/dev/kvm:/dev/kvm"
    environment:
      REPO_URL: https://github.com/my-user/my-repo
      RUNNER_NAME: my-runner
      RUNNER_TOKEN: ${RUNNER_TOKEN}
      RUNNER_WORKDIR: /tmp/runner/work
      RUNNER_SCOPE: "repo"
      LABELS: linux,x64,gpu
    security_opt:
      # needed on SELinux systems to allow docker container to manage other docker containers
      - label:disable
    volumes:
      - "/var/run/docker.sock:/var/run/docker.sock"
      - "/tmp/my-runner:/tmp/runner"
      # note: a quirk of docker-in-docker is that this path
      # needs to be the same path on host and inside the container,
      # docker mgmt cmds run outside of docker but expect the paths from within

Please note that while this solution worked in this particular instance, it may not be the most optimal depending on the specifics of your setup and needs.