[Bug 55411] sysfs per-cpu cpufreq subdirs/symlinks screwed up after s2ram

bugzilla-daemon
2013-03-18T09:56:04Z

--- Comment #4 from Duncan <1i5t5.duncan@cox.net> 2013-03-18 09:56:04 ---
Created an attachment (id=95721)
--> (https://bugzilla.kernel.org/attachment.cgi?id=95721)
grep . cpu?/cpufreq/* (good/pre-suspend)

Good/pre-s2ram grep . cpu?/cpufreq/*

I deliberately redirected STDERR as well to hilite a question I've always had,
as this is the best chance I suppose I'll get for a good answer:

Obviously as non-root:

grep: /sys/devices/system/cpu/cpu?/cpufreq/cpuinfo_cur_freq: Permission denied

Root is required to read cpuinfo_cur_freq.

But /sys/devices/system/cpu/cpu?/cpufreq/scaling_cur_freq:1400000

scaling_cur_freq is readable by world.

What's the difference between the two files and why is cpuinfo_cur_freq so
special as to be the only file in the dir with 0400 perms, as opposed to 0444?