Saw same hang when upgrading from 10.04 to 10.10. Problem for me is the dialog for grub-pc configuration was behind the main update manager's window. Waiting on input. But I couldn't rearrange the windows to accept the grub-pc configuration question.
CPU usage was near 100% with no processes using large amounts of CPU. Sat like that for 2 or 3 hours with no progress. What allowed me to continue was to set System->Preferences->Appearance->Visual Effects from None to Normal setting. Once this was done I could rearrange the windows and click the button to accept grub-pc config. A friend had the same problem and he aborted. I was able to recover one machine as others had after reboot. The other, grub-pc had to be un- installed and re-installed to clean up partial upgrade. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/691569 Title: grub-setup hangs on upgrade (natty) -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs