Hello,

After I updated my system from Tumbleweed AArch64 snapshot 20201218 to snapshot
20210108, I noticed that there appears to be a problem with
kernel-default-5.10.4-1.1. It may be related to the kernel module for the VL805
chip that handles USB on the Raspberry Pi 4. This issue does not affect the
Raspberry Pi 3 which still appear to run normally.

This problem can be seen in a few different ways. When booting the system from
the installation DVD, I have keyboard input in GRUB, but as soon as the system
starts booting into the installer, my keyboard and mouse goes dead. It will
boot all the way to the screen where it asks you to accept the license
agreement (including downloading what it needs to update the installer), but
you cannot use either the mouse or keyboard. You also are unable to interact
with the system during the boot process using the keyboard (to switch from the
splash to a verbose mode). Because of this, you cannot actually install
Tumbleweed 20210108 on the Raspberry Pi 4 from the USB.

I tested this on a Raspberry Pi 4 4GB that boots entirely from a USB drive (no
SD card), I installed 20201218, then I did a zypper dup to 20210108. While you
can interact with the system using the keyboard during GRUB, during the boot
process, it stalls completely, and the system times out and goes into a
recovery prompt (since it can no longer see the USB drive it is booting from).
You cannot type anything here since all USB devices appear to be dead.

I also tested this on the same Raspberry Pi 4 4GB with an SD card. I installed
20201218 using the USB drive, then I did a zypper dup to 20210108. This time,
it will boot up until the prompt to enter a password to unlock encrypted drives
(I use LUKS on my home partition to encrypt it), but you are unable to enter a
password to unlock the drive since the system does not respond to the keyboard.
You are also unable to interact with the system using the keyboard during the
boot process (you can switch between the splash and verbose mode with the
keyboard).

The workaround was to boot the system up using kernel-default-5.9.14-1, since
it was previously installed when I installed 20201218. When I did this, the
system worked as expected both when booted from USB and when booted from an SD
card.

I've seen this behavior previously when I ran the Debian AArch64 and Ubuntu
AArch64 installer. You can interact with the system during GRUB, but as soon as
the installer starts, you lose any ability to use USB devices. It appears also
related to the VL805 chip the Raspberry Pi 4 uses since I was able to boot and
run through the installation for both of these on the Raspberry Pi 3.