ajz3d Nevertheless, I can promise you to do the testing once the appropriate driver version becomes available in the official Debian Testing repository.
@brians, I report back as promised. Yesterday 525.85.12 drivers were uploaded to Debian Testing repository, so I loaded up the test scene and it no longer crashes on Crag.
FWIW I had this same issue, (Karma / optix renders failing with "cuda error illegal adress") on Windows with a GTX390, Houdini 19.5.534. Upgrading to Houdini 19.5.569 and Nvidia Studio Driver 631.61 made the issue go away.