Sorry, this did not fix it. I created a fresh image as follow:
sudo autopkgtest-build-qemu unstable /var/tmp/autopkgtest-unstable.img I then tried to launch a test as follow: $ autopkgtest dhcpcd -- qemu --ram-size 2047 /var/tmp/autopkgtest-unstable.img autopkgtest [23:12:05]: starting date and time: 2024-08-12 23:12:05+0300 autopkgtest [23:12:05]: version 5.39 autopkgtest [23:12:05]: host p8h61; command line: /usr/bin/autopkgtest dhcpcd -- qemu --ram-size 2047 /var/tmp/autopkgtest-unstable.img qemu-system-i386: terminating on signal 15 from pid 34522 (/usr/bin/python3) <VirtSubproc>: failure: timed out waiting for 'login prompt on serial console' autopkgtest [23:13:06]: ERROR: testbed failure: unexpected eof from the testbed Martin-Éric