How to safely use qvm-run with python?

User Support
1

Hello, I am trying to automate some stuff from dom0. I wrote a script to create qubes based on some json files. I wrote it in python, but I am not a very good programmer (learning on my own).

So far I have been using this to send a bash script to a VM that configures some things for me:

subprocess.run(
    ['qvm-run', '-u', 'user', '--no-shell', '--pass-io', vmname, '--', 'bash', '-c', '--', script],
    shell=False, check=False
)

The script is given as a string, and it worked, but if I give it too big of a script, then it failed with error 125:

2026-11-11 00:35:37.136 qrexec-client[605752]: vchan_timeout.c:46:qubes_wait_for_vchan_connection_with_timeout: vchan connection timeout
2026-11-11 00:35:37.136 qrexec-client[605752]: qrexec-client.c:408:main: qrexec connection timeout

The LLM suggested this:

result = subprocess.run(
    ['qvm-run', '-u', 'user', '--no-shell', '--pass-io', name, '--', 'bash', '-s'],
    input=script,
    text=True,
    shell=False,
    check=False,
)

Could someone more knowledgeable than me tell me if this is safe? Will it even work?

2

It seems to work, but I do not know, whether I am being retarded and introducing risks to dom0.