Still doing this on daily build dated 9th April. Looks like it's an issue with configuring secure boot, possibly related to NVIDIA 3rd party drivers: Here is the log from the point just before it starts the death-loop. 2024-04-09T09:47:40.626784+00:00 ubuntu subiquity_log.3969[21274]: INFO:Enable nvidia 2024-04-09T09:47:40.626924+00:00 ubuntu subiquity_log.3969[21274]: DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/lenovo_thinkpad 2024-04-09T09:47:40.627134+00:00 ubuntu subiquity_log.3969[21274]: DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/put_your_quirks_here 2024-04-09T09:47:40.627244+00:00 ubuntu subiquity_log.3969[21274]: DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/dell_latitude 2024-04-09T09:47:40.727617+00:00 ubuntu subiquity_log.3969[21275]: debconf: unable to initialize frontend: Dialog 2024-04-09T09:47:40.727666+00:00 ubuntu subiquity_log.3969[21275]: debconf: (TERM is not set, so the dialog frontend is not usable.) 2024-04-09T09:47:40.727687+00:00 ubuntu subiquity_log.3969[21275]: debconf: falling back to frontend: Readline 2024-04-09T09:47:40.734532+00:00 ubuntu subiquity_log.3969[21275]: debconf: unable to initialize frontend: Readline 2024-04-09T09:47:40.734598+00:00 ubuntu subiquity_log.3969[21275]: debconf: (This frontend requires a controlling tty.) 2024-04-09T09:47:40.734628+00:00 ubuntu subiquity_log.3969[21275]: debconf: falling back to frontend: Teletype 2024-04-09T09:47:40.747688+00:00 ubuntu subiquity_log.3969[21289]: Loading new nvidia-550.67 DKMS files... 2024-04-09T09:47:40.815529+00:00 ubuntu subiquity_log.3969[21393]: Building for 6.8.0-22-generic 2024-04-09T09:47:40.823727+00:00 ubuntu subiquity_log.3969[21289]: Building for architecture x86_64 2024-04-09T09:47:40.855542+00:00 ubuntu subiquity_log.3969[21289]: Building initial module for 6.8.0-22-generic 2024-04-09T09:47:41.054244+00:00 ubuntu subiquity_log.3969[21275]: Configuring Secure Boot 2024-04-09T09:47:41.054310+00:00 ubuntu subiquity_log.3969[21275]: ----------------------- 2024-04-09T09:47:41.054354+00:00 ubuntu subiquity_log.3969[21275]: Your system has UEFI Secure Boot enabled. 2024-04-09T09:47:41.054383+00:00 ubuntu subiquity_log.3969[21275]: UEFI Secure Boot requires additional configuration to work with third-party 2024-04-09T09:47:41.054432+00:00 ubuntu subiquity_log.3969[21275]: drivers. 2024-04-09T09:47:41.054482+00:00 ubuntu subiquity_log.3969[21275]: The system will assist you in configuring UEFI Secure Boot. To permit the use of 2024-04-09T09:47:41.054533+00:00 ubuntu subiquity_log.3969[21275]: third-party drivers, a new Machine-Owner Key (MOK) has been generated. This key 2024-04-09T09:47:41.054561+00:00 ubuntu subiquity_log.3969[21275]: now needs to be enrolled in your system's firmware. 2024-04-09T09:47:41.054604+00:00 ubuntu subiquity_log.3969[21275]: To ensure that this change is being made by you as an authorized user, and not 2024-04-09T09:47:41.054625+00:00 ubuntu subiquity_log.3969[21275]: by an attacker, you must choose a password now and then confirm the change after 2024-04-09T09:47:41.054655+00:00 ubuntu subiquity_log.3969[21275]: reboot using the same password, in both the "Enroll MOK" and "Change Secure Boot 2024-04-09T09:47:41.054679+00:00 ubuntu subiquity_log.3969[21275]: state" menus that will be presented to you when this system reboots. 2024-04-09T09:47:41.054698+00:00 ubuntu subiquity_log.3969[21275]: If you proceed but do not confirm the password upon reboot, Ubuntu will still be 2024-04-09T09:47:41.054722+00:00 ubuntu subiquity_log.3969[21275]: able to boot on your system but any hardware that requires third-party drivers 2024-04-09T09:47:41.054760+00:00 ubuntu subiquity_log.3969[21275]: to work correctly may not be usable. 2024-04-09T09:47:41.054796+00:00 ubuntu subiquity_log.3969[21275]: Enter a password for Secure Boot. It will be asked again after a reboot. 2024-04-09T09:47:41.054847+00:00 ubuntu subiquity_log.3969[21275]: Enter the same password again to verify you have typed it correctly. 2024-04-09T09:47:41.054886+00:00 ubuntu subiquity_log.3969[21275]: Use of uninitialized value $_[1] in join or string at /usr/share/perl5/Debconf/DbDriver/Stack.pm line 112. 2024-04-09T09:47:41.054925+00:00 ubuntu subiquity_log.3969[21275]: Use of uninitialized value $_[1] in join or string at /usr/share/perl5/Debconf/DbDriver/Stack.pm line 112. 2024-04-09T09:47:41.059128+00:00 ubuntu subiquity_log.3969[21275]: Invalid password 2024-04-09T09:47:41.059162+00:00 ubuntu subiquity_log.3969[21275]: The Secure Boot key you've entered is not valid. The password used must be 2024-04-09T09:47:41.059199+00:00 ubuntu subiquity_log.3969[21275]: between 8 and 16 characters. 2024-04-09T09:47:41.059241+00:00 ubuntu subiquity_log.3969[21275]: Enter a password for Secure Boot. It will be asked again after a reboot. 2024-04-09T09:47:41.059283+00:00 ubuntu subiquity_log.3969[21275]: Enter the same password again to verify you have typed it correctly. 2024-04-09T09:47:41.059316+00:00 ubuntu subiquity_log.3969[21275]: Use of uninitialized value $_[1] in join or string at /usr/share/perl5/Debconf/DbDriver/Stack.pm line 112. 2024-04-09T09:47:41.059350+00:00 ubuntu subiquity_log.3969[21275]: Use of uninitialized value $_[1] in join or string at /usr/share/perl5/Debconf/DbDriver/Stack.pm line 112. 2024-04-09T09:47:41.063008+00:00 ubuntu subiquity_log.3969[21275]: Invalid password