Description of problem: Upgrading to the latest released FC5 kernel breaks CPU frequency scaling on my notbook, which works fine with the previous kernel. Version-Release number of selected component (if applicable): kernel-2.6.17-1.2174_FC5 How reproducible: Every time. Steps to Reproduce: 1. Running kernel 2.6.17-1.2157_FC5, note that CPU frequency scaling is alive and well: [root@madmax ~]# ls /sys/devices/system/cpu/cpu0/cpufreq affected_cpus ondemand scaling_driver cpuinfo_cur_freq scaling_available_frequencies scaling_governor cpuinfo_max_freq scaling_available_governors scaling_max_freq cpuinfo_min_freq scaling_cur_freq scaling_min_freq 2. Reboot with kernel 2.6.17-1.2174_FC5 3. Note that CPU frequency scaling is dead and gone: [root@madmax ~]# ls -l /sys/devices/system/cpu/cpu0/cpufreq ls: /sys/devices/system/cpu/cpu0/cpufreq: No such file or directory Actual results: No CPU frequency scaling available. Expected results: CPU frequency scaling available. Additional info: [root@madmax ~]# cat /proc/cpuinfo processor : 0 vendor_id : GenuineIntel cpu family : 6 model : 9 model name : Intel(R) Pentium(R) M processor 1400MHz stepping : 5 cpu MHz : 600.000 cache size : 1024 KB fdiv_bug : no hlt_bug : no f00f_bug : no coma_bug : no fpu : yes fpu_exception : yes cpuid level : 2 wp : yes flags : fpu vme de pse tsc msr mce cx8 mtrr pge mca cmov pat clflush dts acpi mmx fxsr sse sse2 tm pbe est tm2 bogomips : 1197.27 In my /etc/rc.local, I usually configure frequency scaling like so: /sbin/modprobe cpufreq_ondemand echo "ondemand" > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
A new kernel update has been released (Version: 2.6.18-1.2200.fc5) based upon a new upstream kernel release. Please retest against this new kernel, as a large number of patches go into each upstream release, possibly including changes that may address this problem. This bug has been placed in NEEDINFO state. Due to the large volume of inactive bugs in bugzilla, if this bug is still in this state in two weeks time, it will be closed. Should this bug still be relevant after this period, the reporter can reopen the bug at any time. Any other users on the Cc: list of this bug can request that the bug be reopened by adding a comment to the bug. In the last few updates, some users upgrading from FC4->FC5 have reported that installing a kernel update has left their systems unbootable. If you have been affected by this problem please check you only have one version of device-mapper & lvm2 installed. See bug 207474 for further details. If this bug is a problem preventing you from installing the release this version is filed against, please see bug 169613. If this bug has been fixed, but you are now experiencing a different problem, please file a separate bug for the new problem. Thank you.
In the time since my initial report, I tried it again when kernel-2.6.17-1.2187_FC5 became available. It seemed to work fine on that one. I've just upgraded to kernel-2.6.18-1.2200.fc5 and tested again. Frequency scaling *is* available with this kernel. However, when on battery power, the scaling_max_freq is set to the lowest of the available set of frequencies. This behavior differs from previous versions of the kernel and to my understanding is not how the ondemand governor is supposed to work. However, this may be a separate issue... If you want to mark this issue resolved, I can file a new issue describing that as a separate problem. Bret