On BIOS systems with manual partitioning, a warning message is displayed whether you use an EFI partition or a bios-grub partition (Ubuntu Kylin)

[Aaron Rainbolt]

Test hardware: HP Elitebook 8570p, 3rd gen Intel Core i5, 16 GB RAM, 1 TB SSD, UEFI, Secure Boot disabled in hardware. Test done in GNOME Boxes with SeaBIOS as the firmware.

Expected result: If using manual partitioning, no warnings should be displayed if the selected partition configuration will allow the system to boot successfully and function normally after installation is complete.

Actual result: When installing Ubuntu Kylin on a BIOS system, creating a bios-grub partition and no EFI partition results in a warning about the missing EFI partition. Backing up and creating an EFI partition with no bios-grub partition results in a warning about the missing bios-grub partition. Installing using the bios-grub partition and disregarding the warning about the missing EFI partition results in a bootable, usable system after installation.

Steps to reproduce:

1: Download the latest Ubuntu Kylin 22.04.1 daily ISO.
2: Boot the ISO using GNOME Boxes, ensuring that you do not enable EFI during the initial VM setup.
3: When the installer window appears, change the language to English and click "Install Ubuntu Kylin".
4: Set the keyboard layout as appropriate for your system (the default layout will probably be wrong unless you know Chinese).
5: Proceed through the installer accepting the default options until you get to the "Installation type" screen.
5: When presented with the "Installation type" screen in the installer, select "Something else".
6: Create a 1 MB bios-grub partition, and a single BTRFS partition containing the balance of the disk. Set the BTRFS partition to be mounted at /, then click "Install Now". A warning will appear about the missing EFI partition.
7: Go back, remove all partitions, then create a single 300MB EFI system partition, a single BTRFS partition spanning the rest of the disk, set the BTRFS partition to be mounted at /, and set the bootloader to be installed on the EFI partition, then click "Install Now". A warning will appear about the missing bios-grub partition.
8: Go back again and repeat step 6.
9: Rather than going back, continue with the installation this time, and proceed through the rest of the installer as normal.
10: When the installation is finished, reboot into the installed system. The system will boot and function normally.

ProblemType: Bug
DistroRelease: Ubuntu Kylin 22.04
Package: ubiquity (not installed)
ProcVersionSignature: Ubuntu 5.15.0-43.46-generic 5.15.39
Uname: Linux 5.15.0-43-generic x86_64
ApportVersion: 2.20.11-0ubuntu82.1
Architecture: amd64
CasperMD5CheckResult: pass
CurrentDesktop: UKUI
Date: Wed Aug 3 14:50:23 2022
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed locale=zh_CN keyboard-configuration/layoutcode?=cn maybe-ubiquity quiet splash ---
InstallationDate: Installed on 2022-08-03 (0 days ago)
InstallationMedia: Ubuntu-Kylin 22.04.1 LTS "Jammy Jellyfish" - Release amd64 (20220801)
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Ubuntu QA Website (ubuntuqa)]

This bug has been reported on the Ubuntu ISO testing tracker.

A list of all reports related to this bug can be found here:
http://iso.qa.ubuntu.com/qatracker/reports/bugs/1983512