I think I've solved the mystery. I was very bothered that I was the only/first one having it, given the ubiquity of my hardware. I believe this theory also explains why it sometimes awoke just fine from lid closed, but sometimes was all broken.
I believe my setting for "what to do when lid closes" got lost in upgrade to 18.04, so it wasn't suspending, and maybe wasn't doing anything at all! Then, if I happened to place it on good surfaces, it'd be fine and "wake up". When I placed it on bad surfaces, like bed sheets or other cloths, it'd overheat and cook itself into insanity, so when I opened the lid, it wouldn't "wake up" because it was cooked into a fever dream. This is my best guess. I'll let you know if I experience the issue any more, now that I've explicitly chosen "suspend" for "lid close" in Settings. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1754425 Title: Lots of pcieport and nvme kernel errors - system non-responsive To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gnome-shell/+bug/1754425/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
