This occurs with both the 4.15 stock Ubuntu kernel and the 4.18.5 kernel I updated to in order to get the wifi interface to work. (Updated using uuku)
Things I have tried:
- Installing latest nvidia drivers with ubuntu-drivers autoinstall
- Doing this blacklists the nouveau driver which is the source of many posts on the topic.
- Disabling the nvidia-fallback.service causes the system to black screen on login so I re-enabled that service.
I can't find anything suspicious looking in any of the logs.
[Update 09/19/2018: I ran through the instructions in https://wiki.ubuntu.com/DebuggingKernelSuspend and interestingly the forced suspend command it contains does NOT trigger the crashing behavior! I can resume just fine when I do that - although I had to substitute systemctl suspend for the pm_suspend command since that's no longer available in 18.04 I think? Does closing the lid trigger a different suspend mechanism than systemctl suspend?]