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 151BBC433DF for ; Wed, 27 May 2020 18:12:19 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E1DFC2075A for ; Wed, 27 May 2020 18:12:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2391810AbgE0SMR (ORCPT ); Wed, 27 May 2020 14:12:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:51160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2388720AbgE0SMR (ORCPT ); Wed, 27 May 2020 14:12:17 -0400 Received: from shards.monkeyblade.net (shards.monkeyblade.net [IPv6:2620:137:e000::1:9]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 39434C08C5C1 for ; Wed, 27 May 2020 11:12:17 -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 89D29128B13F5; Wed, 27 May 2020 11:12:14 -0700 (PDT) Date: Wed, 27 May 2020 11:12:11 -0700 (PDT) Message-Id: <20200527.111211.1980078971767456943.davem@davemloft.net> To: ivecera@redhat.com Cc: dcaratti@redhat.com, netdev@vger.kernel.org, tahiliani@nitk.edu.in, jhs@mojatatu.com Subject: Re: [PATCH net] net/sched: fix infinite loop in sch_fq_pie From: David Miller In-Reply-To: <20200527092451.5ae03435@ceranb> References: <416eb03a8ca70b5dfb5e882e2752b7fc13c42f92.1590537338.git.dcaratti@redhat.com> <20200527092451.5ae03435@ceranb> X-Mailer: Mew version 6.8 on Emacs 26.3 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]); Wed, 27 May 2020 11:12:14 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Ivan Vecera Date: Wed, 27 May 2020 09:24:51 +0200 > On Wed, 27 May 2020 02:04:26 +0200 > Davide Caratti wrote: > >> this command hangs forever: >> >> # tc qdisc add dev eth0 root fq_pie flows 65536 >> >> watchdog: BUG: soft lockup - CPU#1 stuck for 23s! [tc:1028] ... >> >> we can't accept 65536 as a valid number for 'nflows', because the loop on >> 'idx' in fq_pie_init() will never end. The extack message is correct, but >> it doesn't say that 0 is not a valid number for 'flows': while at it, fix >> this also. Add a tdc selftest to check correct validation of 'flows'. >> >> CC: Ivan Vecera >> Fixes: ec97ecf1ebe4 ("net: sched: add Flow Queue PIE packet scheduler") >> Signed-off-by: Davide Caratti ... > Good catch, Davide. > > Reviewed-by: Ivan Vecera Applied and queued up for v5.6 -stable, thanks.