I'm having the same problem on a 2008 Mac Pro with dual Xeon E5462s, and kernel 3.16.0-25.33. Was working fine on 14.04.
Very suspicious that we all have dual quad-core Clovertown or Harpertown Xeons. Let me know if you need additional info. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1386473 Title: Not using all cores after upgrade to 14.10 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1386473/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs