Since I can’t upgrade my ancient iPad mini 3 (64GB) for years now, I’ve replaced it with iPad Air M2 (128GB) some time ago. It has sort of better CPU than my MacBook Pro (M1Max). Well close but newer CPU family.
Been wondering what else can it be used other than the easy tasks of entertainment, editing video, and retouching images. Enter UTM SE, running virtual machine locally on iPad.

You can download a bunch of different linux from UTM’s gallery page. Tried a few. All seems to stuck with “Display is not active” after boot. Left it untouched for since then with other priorities. Until recently, found some solutions (at least works on iPad Air M2) with Debian 11 (xfce).
First, it does take a long time to boot, and I mean a long time for real due to no virtualisation on iPadOS. So must be patient for linux to boot.
Second, to fix the “Display is not active”, need to pick “vitro-gpu-gl-pci (GPU Supported)” in the virtual machine’s Settings > Display > Emulated Display Card. After change, must click “Save” to make it into effect. This does fixed the display issue after boot.

Third, greeted with login screen and type the default login and password, I ended up with a blank screen with blue background. No menu whatsoever.

Turns out the xfce settings is kind of wonky and need to be reset. But the fix is rather simple:
Press ALT-CTRL-F1 to go to terminal login. From there, login in as user “debian” again.
cd .config
mv xfc4 xfce4.bak
sudo reboot
and the VM is finally ready to play with. Be warned though. It is slow and you never know when Apple will disable the JIT.
