From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from he.sipsolutions.net ([78.46.109.217]:38798 "EHLO sipsolutions.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751799Ab1HHI32 (ORCPT ); Mon, 8 Aug 2011 04:29:28 -0400 Subject: Re: [PATCHv2 2/2] mac80211: Don't use a buf_size=0 in ADDBA requests From: Johannes Berg To: Helmut Schaa Cc: John Linville , linux-wireless@vger.kernel.org, Kalle Valo In-Reply-To: <1312537579-18950-1-git-send-email-helmut.schaa@googlemail.com> (sfid-20110805_114652_677728_F18AA5DB) References: <1311675508-29005-2-git-send-email-helmut.schaa@googlemail.com> <1312537579-18950-1-git-send-email-helmut.schaa@googlemail.com> (sfid-20110805_114652_677728_F18AA5DB) Content-Type: text/plain; charset="UTF-8" Date: Mon, 08 Aug 2011 10:29:23 +0200 Message-ID: <1312792163.4372.5.camel@jlt3.sipsolutions.net> (sfid-20110808_102935_153348_46B5A636) Mime-Version: 1.0 Sender: linux-wireless-owner@vger.kernel.org List-ID: On Fri, 2011-08-05 at 11:46 +0200, Helmut Schaa wrote: > According to 802.11-2007, 7.3.1.14 it is compliant to use a buf_size of > 0 in ADDBA requests. But some devices (AVM Fritz Stick N) arn't able to > handle that correctly and will reply with an ADDBA reponse with a > buf_size of 0 which in turn will disallow BA sessions for these > devices. > > To work around this problem, initialize hw.max_tx_aggregation_subframes > to the maximum AMPDU buffer size 0x40. > > Using 0 as default for the bufsize was introduced in commit > 5dd36bc933e8be84f8369ac64505a2938f9ce036 (mac80211: allow advertising > correct maximum aggregate size). So, are you saying the problem with getting 0 in replies is solved by not sending 0 in requests? Patch looks fine to me, but it's not clear to me that it's the only thing needed? Acked-by: Johannes Berg johannes