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

bugzilla-daemon
2013-03-18T11:53:47Z

Viresh Kumar <viresh.kumar@linaro.org> changed:

What |Removed |Added
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CC| |viresh.kumar@linaro.org

--- Comment #6 from Viresh Kumar <viresh.kumar@linaro.org> 2013-03-18 11:53:47 ---
(In reply to comment #4)
> Created an attachment (id=95721)
--> (https://bugzilla.kernel.org/attachment.cgi?id=95721) [details]
> 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?

cpuinfo_cur_freq is the freq read from the hardware and so has such
permissions.
It will mostly be same as scaling_cur_freq (software stored value of same
hardware freq).

BTW, I must be the guy who screwed up your system in 3.9-rc .. I have come to
your rescue now and will try to fix it for you.

BTW, it will be good if you can provide me suspend/resume log with all debug
prints enabled.