Would setting root by partition UUID be better than using the partition Label?
On my Raspberry Pi 4 I have used the the PINN installer to install both versions (KDE and Xfce) of Manjaro 20.04 side-by-side on the same 64GB SD card. https://github.com/procount/pinn
After the initial installs I can choose which OS to boot from the boot menu UI. The Manjaro /boot/cmdline.txt files reference the root filesystems by device paths in this initial install.
Then I upgraded each install to the 5.4 kernel:
sudo pacman -S linux-rpi4-next
This upgrade changes the /boot/cmdline.txt files to reference the root fs by partition Label.
The current PINN installer and OS chooser doesn't (yet?) understand naming conventions for the BOOT_MNJRO and ROOT_MNJRO partitions: https://github.com/procount/pinn/issues/395 so I manually renamed my partitions.
The partitions on my SD card look like this:
[pi@rpi-tv ~]$ lsblk -o name,label,fstype,uuid
NAME LABEL FSTYPE UUID
├─mmcblk0p1 RECOVERY vfat 008A-3DED
├─mmcblk0p5 SETTINGS ext4 09bfced7-0530-4a7c-aa48-35b6bbd8b40e
├─mmcblk0p6 BOOT_MNJRO vfat 759B-B584
├─mmcblk0p7 ROOT_MNJRO ext4 e64889d4-b11a-44a3-b002-cd340f5fe90e
├─mmcblk0p8 BOOT_MNJRO vfat 8995-1E55
└─mmcblk0p9 ROOT_MNJRO ext4 79f87218-5acf-4c3a-8083-bfa1b9328d1c
When I boot and use the PINN UI to choose a version of Manjaro to start I (almost) always end up loading the second OS on the card (Xfce in my case), regardless of my choice.
I think that the PINN installer/boot chooser /could/ be updated to manage the appropriate command lines, but would it be more robust for the Manjaro /boot/cmdline.txt to reference the root and boot partitions by UUID?
I have updated /etc/fstab and the /boot/cmdline.txt files in my 2 installs to use UUID=XXXX everywhere, and everything now works as expected, but I think that this configuration is likely to be overwritten with each new kernel upgrade?