Here's how I'd suggest to convert the tests from
tests/avocado/boot_linux_console.py :
Copy the whole LinuxKernelTest class (well, let's drop extract_from_rpm
for now since it is completely unused), so we can copy the test code
with only some few modifications (using the Q800 test as an example here).

Thomas Huth (2):
  tests/functional: Add the LinuxKernelTest for testing the Linux boot
    process
  tests/functional: Convert the m68k Q800 Avocado test into a functional
    test

 MAINTAINERS                               |  1 +
 tests/avocado/boot_linux_console.py       | 24 -------------
 tests/functional/meson.build              |  3 +-
 tests/functional/qemu_test/__init__.py    |  1 +
 tests/functional/qemu_test/linuxkernel.py | 41 +++++++++++++++++++++++
 tests/functional/test_m68k_q800.py        | 37 ++++++++++++++++++++
 6 files changed, 82 insertions(+), 25 deletions(-)
 create mode 100644 tests/functional/qemu_test/linuxkernel.py
 create mode 100755 tests/functional/test_m68k_q800.py

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2.46.0