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Description of problem: cpufreq-info when run as root doesn't seem to understand the Division ID (DID) in the msr which signals the processor's Dynamic FSB Frequency Switching or Super Low Frequency Mode (SLFM) mode is in use. For example, when my SP9600 is idling in 800MHz it is fed a multiplier of 6 but against an 133MHz bus (266MHz reduced to half in SLFM mode). However, cpufreq-info when querying directly the hardware (msr?) reports frequency as 1600MHz. acpi-cpufreq driver seems to know about DID however and if cpufreq-info is run as a user and queries the kernel, it displays the correct 800MHz value. Version-Release number of selected component (if applicable): cpufrequtils-008-2.fc14.x86_64 (probably exists in the i686 version too but no way to check) How reproducible: Always Steps to Reproduce: 1. Login as root 2. run cpufreq-info Actual results: DID bit ignored, wrong frequency displayed when processor in SLFM mode. Expected results: DID bit detected and correct frequency displayed. Additional info: None
This is a difference between --freq and --hwfreq. 'cpufreq-info' gets values for both of them from the cpufreq sysfs interface -- scaling_cur_freq and cpuinfo_cur_freq (available only to root) respectively. If there's an issue, it's not in userspace. Re-assigning to kernel.
Indeed you're correct. There is a discrepancy between the values reported there. However, looking a bit further, it appears to be caused by the infamous linux-phc patch for processor undervolting I recently used. This is not a bug of the Fedora kernel. I'm sorry I've wasted your bandwidth.