Re: [REGRESSION 3.10.1] System does not wake up from suspend

["Srivatsa S. Bhat" <srivatsa.bhat@linux.vnet.ibm.com>]

On 07/17/2013 11:34 AM, Sören Brinkmann wrote:
> On Tue, Jul 16, 2013 at 10:38:20PM -0700, Sören Brinkmann wrote:
>> On Wed, Jul 17, 2013 at 10:27:15AM +0530, Srivatsa S. Bhat wrote:
>>> On 07/17/2013 08:27 AM, Sören Brinkmann wrote:
>>>> On Mon, Jul 15, 2013 at 12:20:19PM +0530, Srivatsa S. Bhat wrote:
>>>>> On 07/15/2013 10:24 AM, Willy Tarreau wrote:
>>>>>> On Sun, Jul 14, 2013 at 09:36:25PM -0700, Sören Brinkmann wrote:
>>>>>>> Hi Greg,
>>>>>>>
>>>>>>> since upgrading to 3.10.1 I find my system not waking up from suspend
>>>>>>> from time to time. Unfortunately, I couldn't figure out how to reliably
>>>>>>> reproduce the issue. Sometimes it works just fine.
>>>>>>>
>>>>>>> All I know so far:
>>>>>>> On 3.10 I had my system completely freezing a few times. But that did
>>>>>>> not seem to be related to suspend/resume. I never experienced the
>>>>>>> behavior described below on 3.10.
>>>>>>>
>>>>>>> On 3.10.1 I hit this bug a few times, that my system did not wake up.
>>>>>>> I.e. the screen stayed black and the power LED kept flashing. But
>>>>>>> nothing brought the system back up and I had to longpress power to reset
>>>>>>> the system.
>>>>>>> I had none of the system freezes like the ones described above anymore.
>>>>>>
>>>>>> Fortunately, 3.10.1 is very small. The only patch it contains which is
>>>>>> related to suspend is 18/19 (cpufreq ondemand governor). Maybe you're
>>>>>> having a problem with cpufreq on this machine in fact.
>>>>>>
>>>>>> You may want to try to force it to performance mode or powersave mode
>>>>>> and try for a while, it is possible that both 3.10 and 3.10.1 will work
>>>>>> fine.
>>>>>>
>>>>>
>>>>> Or, you could try applying the patch shown below on top of 3.10.1 and
>>>>> see if it fixes the suspend/resume regression for you.
>>>>>
>>>>> https://lkml.org/lkml/2013/7/11/661
>>>>>
>>>>> (Just apply patch 1, not the entire patchset).
>>>> So, this didn't end well. With that patch applied I end up in a kernel
>>>> panic on suspend, reproducible - well two out of two is a small test set,
>>>> but anyway. Unfortunately too late to get any information about it
>>>> and my logs don't show anything either. But it's seems worse than the
>>>> rather occasional hangs on resume on the vanilla 3.10.1 kernel.
>>>>
>>>
>>> Kernel panic? Weird.. I suspect something _else_ is wrong. I suggest trying
>>> out the following:
>>>
>>> 1. My patches only touch cpufreq. So completely turn off cpufreq by setting
>>>    CONFIG_CPU_FREQ=n. Then try suspend/resume and see how it goes. If it
>>>    fails, that shows that something _else_ is wrong and you can try a git
>>>    bisect for that.
>> I changed my config like shown below. That one has a two out of two
>> success rate for suspend/resume so far.
>>
>>>
>>>    However, if suspend/resume succeeds with CONFIG_CPU_FREQ=n, then try out
>>>    step 2 below.
>>>
>>> 2. Apply patch 1 (not the entire patchset)
>>>    https://lkml.org/lkml/2013/7/11/661
>> That's the one I already have in my tree
>>
>>>
>>>    On top of that, apply this patch:
>>>    https://patchwork.kernel.org/patch/2827512/
>> This one does not apply. I'll see if I can make it apply.
> Got it ported.
> So, with that additional patch and going back to my original config
> (with cpufreq included), I'm currently at 3 out of 3 successful
> suspend/resume cycles.

Great! :)

> Unless the odds are playing an ill game with me, you should be close to
> the actual culprit.
> 

Thanks for all your testing efforts!

Regards,
Srivatsa S. Bhat