[PROBLEM] Kernel 5.4.32 breaks HDMI

[Darkguy]

TLDR:

• uprading from Kernel 5.4.27 to 5.4.32 breaks HDMI output
• rolling back thorugh BTRFS snapshots or downgrading through apt doesn't fix things
• even re-flashing Xbian doesn't fix things
• using the latest Raspbian gets the picture back
  

Hi,

had to reinstall an RPi due to an SD card failing. Took the opportunity to replace the aging RPi 2B I was using up to that point with an RPi 3B.

I used the latest image (installed to USB instead of SD-card this time), hooked the Pi up to the TV and Ethernet and got the boot animation and Xbian welcome screen. Went to set everything else up through SSH (this installation doubles as a local MariaDB/Samba Server for a few other installations, media files are at a remote location and are being accessed through SSHFS) and the TV was used for other things in the meantime.

At some point, I checked for updates and was offered to upgrade the Kernel from 5.4.27 to 5.4.32. Thought nothing of it, installed it, rebooted a few times (the system was fine through SSH) and eventually went to see if the databases I had restored from SQL dumps from the old installation worked correctly - and had the attached telelvision display "no signal".

Tried a number of various HDMI-related config changes in the config.txt to no avail (mind you, the same config and cable was working for years and everything displayed fine after the inital flash).

Tried the USB in an RPi 3B+ I also had around with the same result. Tried rolling back to a previous snapshot (before the Kernel upgrade and MariaDB installations) with the same result. Re-flashed the USB stick and still got no picture on the 3B.

Put the stick (with the fresh installation) into the 3B+ and it booted/displayed an image. Started setting everything up again (this time with the TV turned on and in sight) and lo and behold, after upgrading the Kernel, same result as before - no picture, not even after rolling back.

So this means, something seemingly is being done to the GPU firmware as well, at least that is my guess. I ended up downloading the latest Raspbian, flashing that and booting it up and got an HDMI signal again.

I once again flashed Xbian, set everything up yet again this morning, made sure not to manually upgrade the Kernel and thought that was it. Everything seemed to work. I did enable auto-updates within Xbian (previously, I had done the updates manually) and thought maybe that Kernel wasn't meant to be used yet and Xbian would handle it.

A few hours later, Kodi displayed a request to reboot, which I did. As you can guess, no picture after that. SSH'd in, and of course, Kernel 5.4.32 had been installed automatically. Sigh.

This time, I tried manually downgrading to the previous Kernel (5.4.27), but it still won't display a picture and the TV still shows "no signal".

Any ideas/fixes or anyone else with the same issue?