I just built an image with…

$ sudo autopkgtest-build-qemu --boot=bios trixie Misc/sink/autopkgtest-images/trixie.qcow2

… which “All went fine”, but it does not work:

autopkgtest [19:45:47]: starting date and time: 2026-04-21 19:45:47+0200
autopkgtest [19:45:47]: version 5.49
autopkgtest [19:45:47]: host tgb1.mirbsd.org; command line: /usr/bin/autopkgtest -B -o klog -s '/var/cache/pbuilder/result-trixie/isc-kea_3.0.3-1~bpo13+1_amd64.changes' -- qemu --baseimage --ram-size=8192 -d Misc/sink/autopkgtest-images/trixie.qcow2
autopkgtest-virt-qemu: DBG: Assuming nothing special needs to be done to set up firmware to boot this machine (boot method: bios)
autopkgtest-virt-qemu: DBG: executing open
autopkgtest-virt-qemu: DBG: qemu architecture: x86_64
autopkgtest-virt-qemu: DBG: qemu command: qemu-system-x86_64
autopkgtest-virt-qemu: DBG: find_free_port: trying 10022
autopkgtest-virt-qemu: DBG: find_free_port: 10022 is free
autopkgtest-virt-qemu: DBG: execute-timeout: qemu-img info --output=json Misc/sink/autopkgtest-images/trixie.qcow2
autopkgtest-virt-qemu: DBG: Creating temporary overlay image in /tmp/autopkgtest-qemu.cehefrhs/overlay.img
autopkgtest-virt-qemu: DBG: execute-timeout: qemu-img create -f qcow2 -F qcow2 -b /home/tg/Misc/sink/autopkgtest-images/trixie.qcow2 /tmp/autopkgtest-qemu.cehefrhs/overlay.img
autopkgtest-virt-qemu: DBG: Forwarding local port 10022 to VM ssh port 22
autopkgtest-virt-qemu: DBG: Detected KVM capable AMD host CPU, enabling nested KVM
autopkgtest-virt-qemu: DBG: full qemu command-line: ['qemu-system-x86_64', '-m', '8192', '-smp', '1', '-nographic', '-device', 'virtio-net-pci,netdev=net0', '-netdev', 'user,id=net0,hostfwd=tcp:127.0.0.1:10022-:22', '-object', 'rng-random,filename=/dev/urandom,id=rng0', '-device', 'virtio-rng-pci,rng=rng0,id=rng-device0', '-monitor', 'unix:/tmp/autopkgtest-qemu.cehefrhs/monitor,server=on,wait=off', '-virtfs', 'local,id=autopkgtest,path=/tmp/autopkgtest-qemu.cehefrhs/shared,security_model=none,mount_tag=autopkgtest', '-device', 'virtio-serial', '-chardev', 'socket,path=/tmp/autopkgtest-qemu.cehefrhs/hvc0,server=on,wait=off,id=hvc0', '-device', 'virtconsole,chardev=hvc0', '-chardev', 'socket,path=/tmp/autopkgtest-qemu.cehefrhs/hvc1,server=on,wait=off,id=hvc1', '-device', 'virtconsole,chardev=hvc1', '-serial', 'unix:/tmp/autopkgtest-qemu.cehefrhs/ttyS0,server=on,wait=off', '-serial', 'unix:/tmp/autopkgtest-qemu.cehefrhs/ttyS1,server=on,wait=off', '-drive', 'index=0,file=/tmp/autopkgtest-qemu.cehefrhs/overlay.img,format=qcow2,cache=unsafe,if=virtio,discard=unmap', '-enable-kvm', '-cpu', 'host']
autopkgtest-virt-qemu: DBG: expect: b' login: '
autopkgtest-virt-qemu: DBG: expect: found "'login prompt on serial console'"
autopkgtest-virt-qemu: DBG: expect: b'ok'
autopkgtest-virt-qemu: DBG: expect: found "b'ok'"
autopkgtest-virt-qemu: DBG: setup_shell(): there already is a shell on hvc1
autopkgtest-virt-qemu: DBG: expect: b'672d125a-bb46-4ea4-ab67-9ab2dc1b0e32[1]'
qemu-system-x86_64: terminating on signal 15 from pid 17665 (/usr/bin/python3)
autopkgtest-virt-qemu: DBG: cleanup...
Unexpected error:
Traceback (most recent call last):
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 869, in mainloop
    command()
    ~~~~~~~^^
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 784, in command
    r = f(c, ce)
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 352, in cmd_open
    caller.hook_open()
    ~~~~~~~~~~~~~~~~^^
  File "/usr/bin/autopkgtest-virt-qemu", line 639, in hook_open
    setup_baseimage(tty, prompt)
    ~~~~~~~~~~~~~~~^^^^^^^^^^^^^
  File "/usr/bin/autopkgtest-virt-qemu", line 310, in setup_baseimage
    VirtSubproc.expect(term, prompt.expected_prompt, 10)
    ~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 332, in expect
    block = sock.recv(4096)
  File "/usr/share/autopkgtest/lib/VirtSubproc.py", line 76, in alarm_handler
    raise Timeout(to)
VirtSubproc.Timeout: 10
autopkgtest [19:46:12]: ERROR: testbed failure: unexpected eof from the testbed

It exits with errorlevel 16.

Also present in the backport.

Lowering severity: an image building tool for a single virt server
failing on a system does not mean the package is RC-buggy.

As I wrote, it’s NOT the image building tools that fails (it works),
but the autopkgtest runner itself.

*sigh…*,
//Thorsten