qemus/qemu-docker

KVM acceleration not detected

Facundojs opened this issue · 8 comments

Facundojs commented

Im testing with this image.
Following specifications, i include it in my docker-compose.yml.

# docker-compose.yml
version: "3.9"

services:
    rest:
         #...
    appium:
          #...
    qemu:
        image: qemux/qemu-docker:latest
        stop_grace_period: 1m
        container_name: qemu
        restart: on-failure
        privileged: true
        environment:
            # DISK_SIZE: "32G"
            ALLOCATE: "N"
            BOOT: "https://dl-cdn.alpinelinux.org/alpine/v3.18/releases/x86_64/alpine-standard-3.18.2-x86_64.iso"
        devices:
            - /dev/kvm
            - /dev/vhost-net
        cap_add:
            - ALL
        ports:
            - 22:22
    android:
        container_name: android
        privileged: true
        env_file: .env
        image: android
        command: opt/android-sdk-linux/emulator/emulator -avd test -netdelay none -netspeed full -no-window -no-audio -no-boot-anim -no-snapshot
        build:
            context: .
            dockerfile: dockerfile
            target: android

networks:
    vlan:
        external: true

And when i run it with docker compose up --build i get the following error:

[+] Building 0.9s (11/11) FINISHED                                                                                                                    
[+] Running 2/2
 ✔ Container android  Created                                                                                                                    0.0s 
 ✔ Container qemu     Recreated                                                                                                                  0.1s 
Attaching to android, qemu
qemu     | ❯ Starting QEMU for Docker v2.20...
qemu     | ❯ ERROR: KVM acceleration not detected (device file missing), see the FAQ about this.
android exited with code 0
qemu exited with code 0

In my pc i checked kvm using kvm-ok and is okey.

OS: Ubuntu 22.04

kroese commented

Can you verify the file /dev/kvm does exist on your host machine? Because the container cannot find it.

Or maybe it has the wrong permissions, the correct default permissions should be 660 and root:kvm ownership for the /dev/kvm file.

Facundojs commented

After verify, kvm is correctly installed in /dev/kvm and kvm-ok return a success message.
Also i gave permissions with command

sudo chmod 660 /dev/kvm    
sudo chown root:kvm /dev/kvm

But error persist with same message

kroese commented

Are you using Docker Swarm by any chance?

Facundojs commented

I think not, when i docker info i got Swarm: inactive

kroese commented

Okay, I have seen this problem one time before and it turned out to be caused by Docker Swarm not supporting passing devices to the container.

But if you are not using that, then it must be something else. Its a really strange issue, because you are passing the device correctly in your compose, but the container cannot see it?

So Im not sure what could be the reason. Are you using a recent version of Docker? Is there anything special about your installation?

Facundojs commented

Im using the last docker version.
I hard reseted my pc days ago so i dont think is a old-version-problem. I install docker following the odicial doc page. Maybe is a newer version problem. Which version of docker do you use?

Client: Docker Engine - Community
 Version:    24.0.4
 Context:    desktop-linux
 Debug Mode: false
 Plugins:
  buildx: Docker Buildx (Docker Inc.)
    Version:  v0.11.0
    Path:     /usr/lib/docker/cli-plugins/docker-buildx
  compose: Docker Compose (Docker Inc.)
    Version:  v2.19.1
    Path:     /usr/lib/docker/cli-plugins/docker-compose
  dev: Docker Dev Environments (Docker Inc.)
    Version:  v0.1.0
    Path:     /usr/lib/docker/cli-plugins/docker-dev
  extension: Manages Docker extensions (Docker Inc.)
    Version:  v0.2.20
    Path:     /usr/lib/docker/cli-plugins/docker-extension
  init: Creates Docker-related starter files for your project (Docker Inc.)
    Version:  v0.1.0-beta.6
    Path:     /usr/lib/docker/cli-plugins/docker-init
  sbom: View the packaged-based Software Bill Of Materials (SBOM) for an image (Anchore Inc.)
    Version:  0.6.0
    Path:     /usr/lib/docker/cli-plugins/docker-sbom
  scan: Docker Scan (Docker Inc.)
    Version:  v0.26.0
    Path:     /usr/lib/docker/cli-plugins/docker-scan
  scout: Command line tool for Docker Scout (Docker Inc.)
    Version:  0.16.1
    Path:     /usr/lib/docker/cli-plugins/docker-scout
kroese commented

I have the same version of Docker and Ubuntu, but I cannot reproduce your problem.

You can add the debug-variable to your compose:

environment:
    DEBUG: "Y"

And it will disable the check for KVM, and launch the system without it. The performance will be slower, but at least you should be able to boot Alpine that way.

kroese commented

Closing because of no response.