Return-path: Received: from mail.w1.fi ([212.71.239.96]:57897 "EHLO li674-96.members.linode.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753426AbbBZKUE (ORCPT ); Thu, 26 Feb 2015 05:20:04 -0500 Date: Thu, 26 Feb 2015 12:20:00 +0200 From: Jouni Malinen To: Linus Torvalds Cc: Felix Fietkau , Thomas =?utf-8?B?SMO8aG4=?= , "Luis R. Rodriguez" , Andrew McGregor , linux-wireless , "ath9k-devel@lists.ath9k.org" , Kalle Valo Subject: Re: [ath9k-devel] AR9462 problems connecting again.. Message-ID: <20150226102000.GA4839@w1.fi> (sfid-20150226_112010_648392_F5948C59) References: <20150223224305.GA30228@w1.fi> <21739.50662.902775.901924@gargle.gargle.HOWL> <20150224102611.GA30806@w1.fi> <80AA1103-EBCD-4C18-A950-B03FF516E5AC@net.t-labs.tu-berlin.de> <20150224181454.GA30859@w1.fi> <54ED56D8.9030806@openwrt.org> <20150225144723.GA6903@w1.fi> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: Sender: linux-wireless-owner@vger.kernel.org List-ID: On Wed, Feb 25, 2015 at 10:14:45AM -0800, Linus Torvalds wrote: > While I realize that people may disagree about the exact details of > how to fix this in the long run, may I suggest that in the meantime we > at least get the two workaround patches applied? > Does anybody hate Jouni's two patches *so* much that they can > articulate *why* it would be wrong to apply them as interim patches? > And if so, do you have better patches for me to try? Because if not.. Of all people, I do actually have some hatred on the one-liner to force minimum rate for all EAPOL TX attempts. That is punishing the vast majority of cases where the AP is perfectly fine with higher MCS rates being used (and MCS 0 being sufficient fallback option) for EAPOL. Being able to use higher TX rates as the initial attempt is a nice feature and even though this may be limited to number of upstream Linux drivers today, that part of the feature is an improvement, IMHO. This can even be more robust in some environments especially when going through long EAP exchange with certain types of interference. That said, it is clear to me that we need to modify the current behavior to be more conservative with some of the EAPOL frame retries. I'm not familiar enough with the current minstrel implementation to prepare a clean patch doing the approach I think that should be used here (replace the last rate with a low basic rate and add couple of tries with it). I have reason to believe that Felix might be able to look at this in couple of weeks, though. In other words, I think I'll send out a more formal version of the patches so that they can be applied now if desired while keeping in mind that we may want to replace the minrate-for-EAPOL with something else later. As far as the EAPOL-Key msg 4/4 retries without encryption patch is concerned, I think I have enough concern on the couple of corner cases that I know it does not address (and may break), so it may take some more time before I'm ready to suggest it (or a bit modified version of it) to be applied, though. -- Jouni Malinen PGP id EFC895FA