Finally found what changed. I updated /etc/fstab to have /proc mounted with hidepid=2,gid=sudo for added security. This works perfectly on 16.04 but totally breaks on 17.10.
To recap: mounting /proc with "nodev,noexec,nosuid" works but adding "hidepid=2,gid=sudo" breaks. ** Tags added: regression -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1754401 Title: mounting /proc with hidepid causes: Fatal server error: (EE) xf86OpenConsole: Cannot open virtual console 1 (Permission denied) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/gdm3/+bug/1754401/+subscriptions -- ubuntu-bugs mailing list email@example.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs