Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.5 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS,USER_AGENT_MUTT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 68BC3C43381 for ; Tue, 12 Mar 2019 21:44:51 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 37DE92077B for ; Tue, 12 Mar 2019 21:44:51 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726427AbfCLVou (ORCPT ); Tue, 12 Mar 2019 17:44:50 -0400 Received: from vulcan.kevinlocke.name ([107.191.43.88]:50222 "EHLO vulcan.kevinlocke.name" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726329AbfCLVot (ORCPT ); Tue, 12 Mar 2019 17:44:49 -0400 Received: from kevinolos (unknown [71.15.201.20]) (Authenticated sender: kevin@kevinlocke.name) by vulcan.kevinlocke.name (Postfix) with ESMTPSA id 493FCDBFD9C; Tue, 12 Mar 2019 21:44:47 +0000 (UTC) Received: by kevinolos (Postfix, from userid 1000) id E7B97130040B; Tue, 12 Mar 2019 15:44:45 -0600 (MDT) Date: Tue, 12 Mar 2019 15:44:45 -0600 From: Kevin Locke To: "Grumbach, Emmanuel" Cc: linuxwifi@intel.com, linux-wireless@vger.kernel.org, "Coelho, Luciano" Subject: Re: [linuxwifi] [RFC] iwlwifi: enable TX AMPDU for some iwldvm Message-ID: <20190312214445.GA20993@kevinolos> Mail-Followup-To: Kevin Locke , "Grumbach, Emmanuel" , linuxwifi@intel.com, linux-wireless@vger.kernel.org, "Coelho, Luciano" References: <20190312171205.GA12792@kevinolos> <0f9132187a5567fa94e396ed317efbae1aa4de14.camel@intel.com> <1b6eaef941d3bc887a9fbedea47c2677e5511cdd.camel@intel.com> <20190312203101.GA19902@kevinolos> <58bd45ab11912eef5c809427449a31800ecdbf53.camel@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <58bd45ab11912eef5c809427449a31800ecdbf53.camel@intel.com> User-Agent: Mutt/1.10.1 (2018-07-13) Sender: linux-wireless-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-wireless@vger.kernel.org On Tue, 2019-03-12 at 20:48 +0000, Grumbach, Emmanuel wrote: > On Tue, 2019-03-12 at 14:31 -0600, Kevin Locke wrote: >> On Tue, 2019-03-12 at 19:47 +0000, Grumbach, Emmanuel wrote: >>> We had issues with reclaim path upon BACK. This is of course a >>> firmware problem... >> >> Does that suggest the issue may have been fixed by a firmware update? >> For reference, I'm currently using "firmware version 9.221.4.1 build >> 25532" from the firmware-iwlwifi Debian package (version 20190114-1). >> >> If it would be helpful, I could attempt to bisect the firmware >> revisions to find the one that fixed it (assuming I can reproduce the >> issue with a previous firmware version). > > Well.. Sorry, I wasn't very "technical". > So the problem was really that we stopped getting BACK notifications > from the firmware and that caused a reclaim stall which in turn was > caught by a Tx queue stuck timer firing in the driver. > I was never able to reproduce this. What I can do is to enable A-MPDU > on my old system that has this same device, just to see what happens. Thanks for the additional details and for offering to try it out, that would be great! > While chasing this bug, I even found another one which bought me a few > moments of fame: > > commit d6ee27eb13beab94056e0de52d81220058ca2297 > Author: Emmanuel Grumbach > Date: Wed Jun 6 09:13:36 2012 +0200 > > iwlwifi: don't mess up the SCD when removing a key > > and in the commit message of that very commit: > > This doesn't seem to fix the higher queues that get stuck > from time to time. > > There were no new versions of the firmware released since then. > I tried to skim through bugzilla, but couldn't find the bugs I was > handling then. Ah. You are right about the firmware version. I should have checked. I see what you mean. I found several reports for TX queue stuck issues in Bugzilla. Perhaps this is one (or one of its many dups): https://bugzilla.kernel.org/show_bug.cgi?id=56581 Let me know if there is anything I can do to help search or test. Thanks again, Kevin