Return-path: Received: from mail-qc0-f179.google.com ([209.85.216.179]:37795 "EHLO mail-qc0-f179.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750736AbbBZFCQ (ORCPT ); Thu, 26 Feb 2015 00:02:16 -0500 Received: by qcrw7 with SMTP id w7so6744853qcr.4 for ; Wed, 25 Feb 2015 21:02:16 -0800 (PST) MIME-Version: 1.0 In-Reply-To: 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> Date: Thu, 26 Feb 2015 16:02:15 +1100 Message-ID: (sfid-20150226_060222_856788_61B0B96D) Subject: Re: [ath9k-devel] AR9462 problems connecting again.. From: Andrew McGregor To: Adrian Chadd Cc: Linus Torvalds , Jouni Malinen , Felix Fietkau , =?UTF-8?B?VGhvbWFzIEjDvGhu?= , "Luis R. Rodriguez" , linux-wireless , "ath9k-devel@lists.ath9k.org" , Kalle Valo Content-Type: text/plain; charset=UTF-8 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Thu, Feb 26, 2015 at 7:22 AM, Adrian Chadd wrote: > On 25 February 2015 at 10:14, 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? >> >> I'm talking about the two from Jouni - the "don't encrypt EAPOL >> frames" one, and the one-liner that makes all EAPOL frames go at the >> lowest data rate. >> >> Even if "lowest data rate" is ridiculously low, and even if that might >> disturb other things going on on the same channel at the same time, >> those authentication packets shouldn't be so common as to be a >> problem. No? >> >> Jouni has a few packet dumps for me, and he's stumped as to what >> exactly is going on, but those two patches (well, the one-liner "low >> data rate EAPOL" in particular, it seems) do seem to make my >> connections go through reliably. >> >> And it seems that other drivers already are working around the EAPOL >> issue in similar ways, judging by the comments about iwlwifi. > > [snip] > >> So I'm sure I can improve reception of my laptop, but that's not the >> point. The point is that bad wireless networks aren't so unusual, and >> right now things clearly don't work as well as they could. >> >> 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.. > > I agree with you. I think you should just have EAPOL frames go out at > the lowest rate for now and then worry about experimenting with more > interesting ways to make EAPOL / DHCP frames cheaper. It fixes a lot > of problems in noisy areas. That hack was hiding around in various > commercial drivers I've seen, and it's been in FreeBSD for a while. > > Same with DHCP traffic too - it's the second set of data frames that > the rate control code sees, and it's the primary reason I dropped the > initial sample rate down in FreeBSD so the DHCP exchange would have a > better chance of succeeding after association. > > > > -adrian +1 Really, who cares about efficiency here; these are rare control packets.