I switched back to the Ubuntu linux-image-4.10.0-33-generic kernel and about 6 reboots later it happened again, so its definitely specific to the Ubuntu kernel. I was able to catch it right as it happened, the last thing before the NMI watchgdog messages occur is:
[ OK ] Reached target Shutdown. The only errors visible on the screen are [FAILED] unmounting /tmp and /var , I always get the failure unmounting /var but not /tmp, maybe that is significant? I had /tmp on a separate partition, I removed its fstab entry so it will be on the / root partition, we'll see if that changes anything. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1713751 Title: soft lockup / stall on CPU when shutting down with hwe 4.10 kernel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux-hwe/+bug/1713751/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
