Re: Problem with 40Mhz on 2.5GHz with Intel 8260

[Volker Mische <volker.mische@gmail.com>]

Hi,

On 09/21/2016 08:54 AM, Emmanuel Grumbach wrote:
>> On 09/20/2016 08:22 AM, Volker Mische wrote:
>>> On 09/20/2016 07:39 AM, Emmanuel Grumbach wrote:
>>>> On Mon, Sep 19, 2016 at 5:00 PM, Volker Mische <volker.mische@gmail.com> wrote:
>>>>> I'm having connectivity issues with an Intel 8260 on a 2.5GHz network
>>>>> when using 40Mhz. I'm getting errors like
>>>>>
>>>>>     Queue 2 stuck for 10000 ms.
>>>>>
>>>>> I've upgrade my system to the firmware version 21 (21.373438.0) and
>>>>> Kernel 4.8.0-rc6 in hope that it fixes the issue and to be able to debug
>>>>> the problem.
>>>>>
>>>>> I then found the page about platform noise [1]. I don't have any issue
>>>>> for several hours now (normally I was hitting the issue every few
>>>>> minutes) as I've set the cfg80211_disable_40mhz_24ghz parameter.
>>
>>>> We tried a few times to debug those, but they take a very long time to debug
>>>> since typically we need lots of reproductions and the firmware team
>>>> doesn't always
>>>> the time to look at the data immediately so in the end, the people who
>>>> reported this
>>>> originally went away.
>>>> Note that 40MHz on 2.4GHz is not an optimal configuration in crowded
>>>> environment,
>>>> but if you live in a place where you are pretty much the only one using those
>>>> frequencies, then, it can be beneficial.
>>>
>>> It's at home. I normally see only one other wifi (I need to check which
>>> frequency that one is using).
>>>
>>>
>>>> What you can try is to disable low power states (by using power_scheme
>>>> in iwlmvm) and see if it helps.
>>>
>>> I will try that.
>>
>> I've set the iwlmvm power_scheme to 1 (and allowed the 40Mhz
>> connection). First I thought it's good, but after a while the queue
>> still got stuck. Especially after waking up from a suspend (not sure if
>> that matters).
> 
> Ok - good to know.
> 
>>
>> What are the next steps?
> 
> can you try to unplug the power cord? I had reports that said that
> this can help. Again, just a debug step to give us a hint of what you
> can be experiencing.

Unplug without any module parameters or combined with the
cfg80211_disable_40mhz_24ghz or power_scheme one?


> Besides this, we need to go for firmware debugging. But as I said,
> don't expect this to be fast and easy. Please open a bug in
> bugzilla.kernel.org. CC linuxwifi@intel.com and we will guide you
> there on how to provide the information we need.

OK, will do once I did try with unplugging. I've seen previous reports
on the issue. As I'm already running a Kernel compiled from source I
hope that at least I can move fast :)

Cheers,
  Volker