From mboxrd@z Thu Jan 1 00:00:00 1970 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=-3.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=no 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 C75C6C432C0 for ; Mon, 25 Nov 2019 07:55:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 3BAC52071E for ; Mon, 25 Nov 2019 07:55:32 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=dlink.ru header.i=@dlink.ru header.b="jXrsbGoj" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1725992AbfKYHzb (ORCPT ); Mon, 25 Nov 2019 02:55:31 -0500 Received: from mail.dlink.ru ([178.170.168.18]:48526 "EHLO fd.dlink.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725793AbfKYHza (ORCPT ); Mon, 25 Nov 2019 02:55:30 -0500 Received: by fd.dlink.ru (Postfix, from userid 5000) id 48AB31B20A89; Mon, 25 Nov 2019 10:55:26 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 fd.dlink.ru 48AB31B20A89 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=dlink.ru; s=mail; t=1574668526; bh=hvwfIe2HDk9ILc0UQVhg8dykjGSlCUAMb+1VVK6Nd7Y=; h=Date:From:To:Cc:Subject:In-Reply-To:References; b=jXrsbGojjUz1itx5gHaRBnrS0/KftQSPHUmsgorWimUflZEMPZIY7eOsNc+0E1oD2 /cO8gHwH1JcsL6WUqIHiA9OAvoLtELouYzf5Fr04Ci3JXZrLmIsIB5kPH8RzPUA38n 8OCr34LDlAPU2S/OqWInsSh1CgE2dzBJNqggvymU= Received: from mail.rzn.dlink.ru (mail.rzn.dlink.ru [178.170.168.13]) by fd.dlink.ru (Postfix) with ESMTP id 9B8251B204A3; Mon, 25 Nov 2019 10:55:17 +0300 (MSK) DKIM-Filter: OpenDKIM Filter v2.11.0 fd.dlink.ru 9B8251B204A3 Received: from mail.rzn.dlink.ru (localhost [127.0.0.1]) by mail.rzn.dlink.ru (Postfix) with ESMTP id C9F2A1B2175B; Mon, 25 Nov 2019 10:54:44 +0300 (MSK) Received: from mail.rzn.dlink.ru (localhost [127.0.0.1]) by mail.rzn.dlink.ru (Postfix) with ESMTPA; Mon, 25 Nov 2019 10:54:44 +0300 (MSK) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Date: Mon, 25 Nov 2019 10:54:44 +0300 From: Alexander Lobakin To: Nicholas Johnson Cc: David Miller , ecree@solarflare.com, jiri@mellanox.com, edumazet@google.com, idosch@mellanox.com, pabeni@redhat.com, petrm@mellanox.com, sd@queasysnail.net, f.fainelli@gmail.com, jaswinder.singh@linaro.org, ilias.apalodimas@linaro.org, netdev@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 net-next] net: core: use listified Rx for GRO_NORMAL in napi_gro_receive() In-Reply-To: References: <20191014080033.12407-1-alobakin@dlink.ru> <20191015.181649.949805234862708186.davem@davemloft.net> <7e68da00d7c129a8ce290229743beb3d@dlink.ru> User-Agent: Roundcube Webmail/1.4.0 Message-ID: X-Sender: alobakin@dlink.ru Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Nicholas Johnson wrote 25.11.2019 10:29: > Hi, > > On Wed, Oct 16, 2019 at 10:31:31AM +0300, Alexander Lobakin wrote: >> David Miller wrote 16.10.2019 04:16: >> > From: Alexander Lobakin >> > Date: Mon, 14 Oct 2019 11:00:33 +0300 >> > >> > > Commit 323ebb61e32b4 ("net: use listified RX for handling GRO_NORMAL >> > > skbs") made use of listified skb processing for the users of >> > > napi_gro_frags(). >> > > The same technique can be used in a way more common napi_gro_receive() >> > > to speed up non-merged (GRO_NORMAL) skbs for a wide range of drivers >> > > including gro_cells and mac80211 users. >> > > This slightly changes the return value in cases where skb is being >> > > dropped by the core stack, but it seems to have no impact on related >> > > drivers' functionality. >> > > gro_normal_batch is left untouched as it's very individual for every >> > > single system configuration and might be tuned in manual order to >> > > achieve an optimal performance. >> > > >> > > Signed-off-by: Alexander Lobakin >> > > Acked-by: Edward Cree >> > >> > Applied, thank you. >> >> David, Edward, Eric, Ilias, >> thank you for your time. >> >> Regards, >> ᚷ ᛖ ᚢ ᚦ ᚠ ᚱ > > I am very sorry to be the bearer of bad news. It appears that this > commit is causing a regression in Linux 5.4.0-rc8-next-20191122, > preventing me from connecting to Wi-Fi networks. I have a Dell XPS 9370 > (Intel Core i7-8650U) with Intel Wireless 8265 [8086:24fd]. Hi! It's a bit strange as this commit doesn't directly affect the packet flow. I don't have any iwlwifi hardware at the moment, so let's see if anyone else will be able to reproduce this (for now, it is the first report in a ~6 weeks after applying to net-next). Anyway, I'll investigate iwlwifi's Rx processing -- maybe I could find something driver-specific that might produce this. Thank you for the report. > I did a bisect, and this commit was named the culprit. I then applied > the reverse patch on another clone of Linux next-20191122, and it > started working. > > 6570bc79c0dfff0f228b7afd2de720fb4e84d61d > net: core: use listified Rx for GRO_NORMAL in napi_gro_receive() > > You can see more at the bug report I filed at [0]. > > [0] > https://bugzilla.kernel.org/show_bug.cgi?id=205647 > > I called on others at [0] to try to reproduce this - you should not > pull > a patch because of a single reporter - as I could be wrong. > > Please let me know if you want me to give more debugging information or > test any potential fixes. I am happy to help to fix this. :) > > Kind regards, > Nicholas Johnson Regards, ᚷ ᛖ ᚢ ᚦ ᚠ ᚱ