Return-path: Received: from mail-it0-f54.google.com ([209.85.214.54]:35803 "EHLO mail-it0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752720AbcITFjY (ORCPT ); Tue, 20 Sep 2016 01:39:24 -0400 Received: by mail-it0-f54.google.com with SMTP id r192so88769380ita.0 for ; Mon, 19 Sep 2016 22:39:24 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: <24d0d9c5-7695-9364-c5fa-97e9d52712dc@gmail.com> References: <24d0d9c5-7695-9364-c5fa-97e9d52712dc@gmail.com> From: Emmanuel Grumbach Date: Tue, 20 Sep 2016 08:39:23 +0300 Message-ID: (sfid-20160920_073928_454462_41B1D66A) Subject: Re: Problem with 40Mhz on 2.5GHz with Intel 8260 To: Volker Mische Cc: linux-wireless Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi, On Mon, Sep 19, 2016 at 5:00 PM, Volker Mische wrote: > Hi, > > 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. > > Now I wonder, is it worth debugging the issue with being on 40MHz or is > disabling the proper solution and I should bother. Well... depends whom you ask and how much time you have :) 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. What you can try is to disable low power states (by using power_scheme in iwlmvm) and see if it helps. This setting has a bigger impact than cfg80211_disable_40mhz_24ghz but it can give a hint as where the problem is coming from. > > [1]: > https://wireless.wiki.kernel.org/en/users/drivers/iwlwifi#about_platform_noise > > Cheers, > Volker