Error booting Kubuntu 20.04

[q4osteam]

Hello,

We are installing Kubuntu 20.04 (kubuntu-20.04-desktop-amd64.iso)

• Windows 10
• Virtualbox machine
• EFI activated
• Using "--isopath" method.

Wubi installer processed fine. Kubuntu started to boot, but after a while an error message appeared, see the attachment. We can reproduce the exact same error in KVM virtual machine.

[hakuna-m]

It is a possible duplicate of a known issue. see release notes

• user confirmation ("Continue") is necessary for new questions:

Go back to the menu and resume partitioning?

No EFI System Partition was found. This system will likely not be able to boot successfully, and the installation process may fail.

Please go back and add an EFI System Partition, or continue at your own risk.

Go back to the menu and correct this problem?

It is normally required for you to create a separate partition for the boot loader code in order to boot your system in EFI mode. This partition should be marked for use as an "EFI boot partition" and should be at least 35 MB in size. Note that this is not the same as a partition mounted on /boot.

If you do not go back to the partitioning menu and correct this error, boot loader installation may fail later, although it may still be possible to install the boot loader to a partition.

[q4osteam]

Even if we confirm by the "Continue" button, Kubuntu doesn't start. Another messagebox appears, see attachment. On clicking "Ignore button" the first error arises and cycle starts again. It's not possible to bypass this error to continue Kubuntu iso image booting.

[hakuna-m]

Does the issue only affect Kubuntu 20.04 (Kubuntu 19.10 and Ubuntu 20.04 work) for your configuration ?

Changes of Ubiquity has been the reason for the known issue of skipable warnings. Maybe, some additional parts for Kubuntu causes additional issues.

If there are serious errors instead of skipable warnings, we will try to create a new preseed file as workaround.

We hope that it is not necessary that we also need fixes for Ubiquity which is not part of our project.

[q4osteam]

Well, we will test Ubuntu 20.04 and post a result.

[q4osteam]

Ubuntu 20.04 installs just fine, except the need of confirmation the two dialogues. Configuration: Windows 10 in Virtualbox, EFI activated, --isopath method.
Unfortunately, no way to install Kubuntu 20.04 on exact the same configuration, see above.

[hakuna-m]

Ubuntu 20.04 installs just fine, except the need of confirmation the two dialogues.

Thanks. Your test confirms our previous tests.

Unfortunately, no way to install Kubuntu 20.04 on exact the same configuration, see above.

OK. We set a higher priority to fix the known issue. Probably, it works for Kubuntu, if we can avoid error handling for the first warning message.

[Aero37]

I get this same error on a normal desktop that's not a virtual machine and not using --isopath. After clicking either retry or ignore on the 2nd box, the screen just shows the background but doesn't move further. A hard reset is required to go back to windows. Pressing the power button on the desktop brings the Kubuntu logo up but it never finishes shutting down.

Everything is default except Kubuntu 20.04 chosen. I will install an older Kubuntu LTS and upgrade to try to work around this.

Update: Kubuntu 18.04 works. The same things seems to happen in Kubuntu 18.04 except only the first window pops up. I click ignore and then wait but the background is the only thing shown. If you wait long enough, however the computer restarts and everything works as expected. Kubuntu 18.04 successfully installs, just weirdly. May want to make a note of that besides the installation bar just not showing.

[hakuna-m]

Good news. We debugged Ubiquity to solve the issues with the EFI bootloader error messages. There are two possible entries for our preseed file to suppress the questions.

d-i partman-efi/no_efi boolean false
d-i partman-partitioning/no_bootable_efi boolean false  

Whereas the "partman-efi/no_efi" entry works out of the box, the "partman-partitioning/no_bootable_efi" does not work. The resaon is that the script /usr/lib/partman/check.d/08biosgrub on ISO within casper/filesystem.squashfs sets "partman-partitioning/no_bootable_efi" always to true. So we can skip the message but we cannot skip the error. An endless loop occurs.

As a workaround we can disable "db_set" in /usr/lib/partman/check.d/08biosgrub with the next release. So we can use preseed file to automatize installation.

[hakuna-m]

We tested Kubuntu 20.04.1 with wubi20041r342. The issue has been solved.