QEMUDriver is killing the QEMU process when using the "power on" command

[LukeHackwell]

Hi!

I'm trying to get a setup working for the QEMUDriver.

I am using this guide as a base for my QEMU config - Boot ARM64 virtual machines on QEMU. I'm able to run this outside of Labgrid with no issues.

Here's my config for the QEMUDriver, based on to the guide above:

targets:
  main:
    resources:
      RemotePlace:
        name: my_board
    drivers:
      QEMUDriver:
        qemu_bin: 'qemu-system-aarch64'
        machine: 'virt'
        cpu: 'max'
        memory: '4G'
        extra_args: '-drive if=pflash,format=raw,file=efi.img,readonly=on -drive if=pflash,format=raw,file=varstore.img -drive if=none,file=ubuntu-24.04-server-cloudimg-arm64.img,id=hd0 -drive file=user-data.img,format=raw -device virtio-blk-device,drive=hd0 -netdev type=tap,id=net0 -device virtio-net-device,netdev=net0'

When I run labgrid-client -c qemu.config power on, I get the following error:
qemu-system-aarch64: terminating on signal 15 from pid <PID> (<PYTHON PATH>)

After debugging this, it seems that Labgrid is executing the QEMUDriver.on method which brings up the QEMU process. However, once it has finished it exits and triggers the QEMUDriver._atexit method, which kills the QEMU process, causing QEMU to print the error above.

I also get the same error when I run an "empty config":

targets:
  main:
    resources:
      RemotePlace:
        name: my_board
    drivers:
      QEMUDriver:
        qemu_bin: 'qemu-system-x86_64'
        machine: 'q35'
        cpu: 'max'
        memory: '4G'
        extra_args: ''

In this case I'd also expect the QEMU process to stay up

Any help is much appreciated.

Thanks!

[Emantor]

We can't keep the qemu process running since the client is exiting. It's possible to get the exact command arguments from the QemuDriver with qemu_get_base_args(), this way you can use labgrid as a library to retrieve the arguments and than spawn qemu yourself:

labgrid/labgrid/driver/qemudriver.py

Line 125 in 7f2c8fc

def get_qemu_base_args(self):

The tests for barebox use this to spawn qemu interactively, see here.

[LukeHackwell]

Ah okay thank-you. So its not really possible to use the QEMU driver via the labgrid-client CLI, but it is possible to use it as a utility in a script?

[Bastian-Krause]

Correct.