A few times now after updating to the 515 driver I’ve experienced lock-ups. The display is frozen with the lock screen. Normally when I move the mouse, a prompt for the password will appear. But that does not happen. The machine responded to magic-sysrq and I was able to switch into a terminal and run the nvidia bug report script.
The notable entries from the system log look like this:
[143167.318664] nvidia-modeset: ERROR: GPU:0: Error while waiting for GPU progress: 0x0000c57d:0 2:0:256:240
nvidia-bug-report.log.gz (980.4 KB)