Cannot access GUI after kernel update - problem with nvidia drivers on ubuntu

Dear Nvidia community,

After a recent Kernel update on my Workstation, the nvidia graphics drivers stopped working. Unfortunately some attempts at fixing the issues were done in my absence but were not documented so I’m not entirely sure of some of the changes that were done.

My setup:
nvidia-bug-report.log.gz (567.2 KB)

OS : Linux-5.4.0-77-generic-x86_64-with-debian-buster-sid - Ubuntu 18.04
GPUS : dual Quadro RTX 6000 - driver version 460.84

Description of the issue:
The machine boots and then freezes on a blue login screen with with unresponsive mouse and keyboard (see image). I emphasize that my machine has ubuntu 18.04 installed so I would expect the usual purple background to be visible.
The driver seems to be installed correctly as ‘nvidia-smi’ yields the expected output.

What I tried so far:

  • purging all nvidia files and reinstalling from scratch both via .run installer and ubuntu repositories following the correct instructions ( i.e blacklisting nouveau drivers , disabling secure boot , installing prime-select, deleting xorg.conf files etc.)

I’ll attach the nvidia-bug report,

I am deeply grateful for any advice/help,

Adriano