Return-path: Received: from purkki.adurom.net ([80.68.90.206]:33235 "EHLO purkki.adurom.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758201Ab2EJJqP (ORCPT ); Thu, 10 May 2012 05:46:15 -0400 From: Kalle Valo To: Soumik DAS Cc: John Linville , linux-wireless , Johannes Berg Subject: Re: [PATCH] mac80211: Increment probe_send_count earlier References: <2E48302EED53D048A7BA72B0A307FB511FB9009098@EXDCVYMBSTM005.EQ1STM.local> <87vck48q92.fsf@purkki.adurom.net> <2E48302EED53D048A7BA72B0A307FB511FB9009215@EXDCVYMBSTM005.EQ1STM.local> Date: Thu, 10 May 2012 12:46:10 +0300 In-Reply-To: <2E48302EED53D048A7BA72B0A307FB511FB9009215@EXDCVYMBSTM005.EQ1STM.local> (Soumik DAS's message of "Thu, 10 May 2012 10:43:57 +0200") Message-ID: <87mx5g8j31.fsf@purkki.adurom.net> (sfid-20120510_114618_699775_9FD8F2D6) MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Sender: linux-wireless-owner@vger.kernel.org List-ID: Hi Soumik, Soumik DAS writes: > In some cases the sequence of events gets changed - > a. call ieee80211_send_nullfunc() > (current thread gets scheduled out/pre-empted at this point) > b. null frame gets transmitted and acked > c. probe_send_count is incremented > d. mac80211 waits for some specified timeout and checks that probe_send_count is still > 0. It concludes that AP did not acknowledge the null frame and disassociates from the current AP. > e. After a scan STA again re-associate with the same AP. Ok, so there's a race in mac80211? You should describe the race in the commit log so that a random developer understands what's happening. It doesn't need to be anything fancy, usually just few sentences is enough to give sufficient background for the patch. Where the race is, how often it happens and how to fix it properly, that sort of things. I repeat this a lot (sorry!) but the most important question the commit log should answer is "Why?". The question "What?" isn't actually that important as anyone can read the patch themselves. -- Kalle Valo