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=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 235C6C3A5A9 for ; Mon, 4 May 2020 18:51:15 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id F3A6B20721 for ; Mon, 4 May 2020 18:51:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726635AbgEDSvN (ORCPT ); Mon, 4 May 2020 14:51:13 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:36768 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S1726334AbgEDSvN (ORCPT ); Mon, 4 May 2020 14:51:13 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 76BEDC061A0E for ; Mon, 4 May 2020 11:51:13 -0700 (PDT) Received: from localhost (unknown [IPv6:2601:601:9f00:477::3d5]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id C0D1111F5F61A; Mon, 4 May 2020 11:51:12 -0700 (PDT) Date: Mon, 04 May 2020 11:51:11 -0700 (PDT) Message-Id: <20200504.115111.2011826515282537226.davem@davemloft.net> To: brouer@redhat.com Cc: netdev@vger.kernel.org, kuba@kernel.org, stephen@networkplumber.org, dsahern@gmail.com Subject: Re: [PATCH net-next V2] net: sched: fallback to qdisc noqueue if default qdisc setup fail From: David Miller In-Reply-To: <158824694174.2180470.8094886910962590764.stgit@firesoul> References: <158824694174.2180470.8094886910962590764.stgit@firesoul> X-Mailer: Mew version 6.8 on Emacs 26.1 Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 04 May 2020 11:51:12 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jesper Dangaard Brouer Date: Thu, 30 Apr 2020 13:42:22 +0200 > Currently if the default qdisc setup/init fails, the device ends up with > qdisc "noop", which causes all TX packets to get dropped. > > With the introduction of sysctl net/core/default_qdisc it is possible > to change the default qdisc to be more advanced, which opens for the > possibility that Qdisc_ops->init() can fail. > > This patch detect these kind of failures, and choose to fallback to > qdisc "noqueue", which is so simple that its init call will not fail. > This allows the interface to continue functioning. > > V2: > As this also captures memory failures, which are transient, the > device is not kept in IFF_NO_QUEUE state. This allows the net_device > to retry to default qdisc assignment. > > Signed-off-by: Jesper Dangaard Brouer Applied, thanks.