Return-path: Received: from senator.holtmann.net ([87.106.208.187]:54626 "EHLO mail.holtmann.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751814AbZGaT13 (ORCPT ); Fri, 31 Jul 2009 15:27:29 -0400 Subject: Re: [PATCH 000/002] Fix frequent reconnects caused by new conection monitor From: Marcel Holtmann To: Maxim Levitsky Cc: reinette chatre , linux-wireless , linville , Johannes Berg In-Reply-To: <1249067293.19089.10.camel@maxim-laptop> References: <1249056817.20593.1.camel@maxim-laptop> <1249066338.30019.214.camel@rc-desk> <1249067293.19089.10.camel@maxim-laptop> Content-Type: text/plain Date: Fri, 31 Jul 2009 12:27:29 -0700 Message-Id: <1249068449.23662.17.camel@localhost.localdomain> Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi Maxim, > > > Hi, here is the updated version of these two patches that fix the > > > $SUBJECT issue. > > > > > > I attach these (in case mailer mangles them), and reply with patches. > > > > > > Tested both with low quality signal, and beacon loss. > > > Lack of TX is found, every 30 seconds now, and quite reliable. > > > Lack of beacons, triggers probe like it did every 2 seconds. > > > > Thanks! > > > > I've been running with this for two hours now with no disconnects. This > > is where before the patches I would get disconnected after a few > > minutes. I did get two "No probe response from AP xx:xx:xx:xx:xx:xx > > after 500ms, try 1" messages in my log. > This is normal, or at least can be normal, I patched the driver to > display this message, when there is a probe timeout, but instead of > disconnect, it retries, currently 5 times, but this can be even further > increased is necessarily. > (these messages are only in logs when verbose mac debugging is enabled) > > I don't know exactly why probes aren't answered, but I strongly suspect > that my AP sometimes 'goes out to lunch' and then answers, since > typically after a failed probe it sends many replies. > (Or it could be some buffering done by iwl3945 microcode). I currently > can't monitor the connection from outside, but as soon as I can I see > whether the above is true. Nevertheless if signal quality isn't great, > there are valid reasons for probe loss, and it shouldn't cause all the > fuzz (and since I use WPA2, every reconnection causes whole WPA > handshake to be preformed, and this takes at least 2 seconds, and if a > reconnection happens each 5 seconds, it gets very very annoying, and > almost unusable. I am testing your patches and so far so good. Seems to be working perfectly fine. I see this in the logs: [41027.333419] wlan0: detected beacon loss from AP - sending probe request [41027.389260] wlan0: cancelling probereq poll due to a received beacon [41027.793518] No probe response from AP 00:1c:f0:62:88:5b after 500ms, try 1 [41028.292731] No probe response from AP 00:1c:f0:62:88:5b after 500ms, try 2 Need to watch out if this pattern emerges and if the beacon loss trigger might give us an indication. Maybe the ucode is just not ready then. Regards Marcel