I investigated further and something is really messed up with this last kernel. Every time I switch to a tty, the laptop freezes and the tty displays a huge list of error messages. And this happens even without "threadirqs". I'm attaching photos of the errors.
** Attachment added: "pictures - kernel commit 2cb85c0845e5826b789d755c97e13e8d5dc85368" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1269404/+attachment/3971627/+files/error-commit-2cb85c0845e5826b789d755c97e13e8d5dc85368.tar.gz -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1269404 Title: BUG: soft lockup - CPU#2 stuck for 22s! [systemd-udevd:546] To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1269404/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs