The real problem seems to be indicated by the scaling driver: p4-clockmod: Warning: EST-capable CPU detected. The acpi-cpufreq module offers voltage scaling in addition to frequency scaling. You should use that instead of p4-clockmod, if possible.
Following the advise by simply renaming p4-clockmod.ko makes the kernel use acpi-cpufreq and then frequency scaling works again. So the bug is that the kernel loads the wrong scaling driver despite knowing better. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/799613 Title: [regression] ondemand governor failed, too long transition latency of HW, fallback to performance governor To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/799613/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
