Re: [PATCH] cpufreq: fix garbage kobj on errors during suspend/resume

Srivatsa S. Bhat
2013-12-09T06:48:06Z

On 12/09/2013 08:29 AM, Lan Tianyu wrote:
> 2013/12/5 Rafael J. Wysocki <rjw@rjwysocki.net>:
>> On Wednesday, December 04, 2013 04:02:18 PM viresh kumar wrote:
>>> On Tuesday 03 December 2013 04:44 PM, Bjørn Mork wrote:
>>>> This is effectively a revert of commit 5302c3fb2e62 ("cpufreq: Perform
>>>> light-weight init/teardown during suspend/resume"), which enabled
>>>> suspend/resume optimizations leaving the sysfs files in place.
[...]
>> I took the Bjorn's patch for 3.13 and this one I can queued up for 3.14,
>> but for that I guess it should contain a revert of the change made by the
>> Bjorn's patch.
>
> This patch causes a s3 regression. Cc:Martin Ziegler
> https://bugzilla.kernel.org/show_bug.cgi?id=66751
>

Hmm.. With Bjorn's patch applied, the cpufreq hotplug callback should become
identical to what happens during regular CPU hotplug. So is regular CPU
hotplug also failing for you, Martin?

You can do CPU hotplug by:

CPU offline:
echo 0 > /sys/devices/system/cpu/cpu<num>/online

CPU online:
echo 1 > /sys/devices/system/cpu/cpu<num>/online

Bjorn's patch looks pretty innocuous to me.. I couldn't catch any obvious
bug looking at the code. So answer to the above question should help us dig
deeper.

Regards,
Srivatsa S. Bhat