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=-4.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 66F8DC04AB5 for ; Thu, 6 Jun 2019 18:42:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4129920868 for ; Thu, 6 Jun 2019 18:42:58 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726917AbfFFSm5 (ORCPT ); Thu, 6 Jun 2019 14:42:57 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:55674 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726066AbfFFSm5 (ORCPT ); Thu, 6 Jun 2019 14:42:57 -0400 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::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 74E2914DE9A90; Thu, 6 Jun 2019 11:42:56 -0700 (PDT) Date: Thu, 06 Jun 2019 11:42:55 -0700 (PDT) Message-Id: <20190606.114255.365204463731451300.davem@davemloft.net> To: jcline@redhat.com Cc: dsahern@kernel.org, netdev@vger.kernel.org, ian.kumlien@gmail.com, alan.maguire@oracle.com, dsahern@gmail.com Subject: Re: [PATCH net] neighbor: Reset gc_entries counter if new entry is released before insert From: David Miller In-Reply-To: <20190606170729.GA15882@laptop.jcline.org> References: <20190502010834.25519-1-dsahern@kernel.org> <20190504.004100.415091334346243894.davem@davemloft.net> <20190606170729.GA15882@laptop.jcline.org> 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]); Thu, 06 Jun 2019 11:42:56 -0700 (PDT) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Jeremy Cline Date: Thu, 6 Jun 2019 13:07:29 -0400 > Hi, > > On Sat, May 04, 2019 at 12:41:00AM -0400, David Miller wrote: >> From: David Ahern >> Date: Wed, 1 May 2019 18:08:34 -0700 >> >> > From: David Ahern >> > >> > Ian and Alan both reported seeing overflows after upgrades to 5.x kernels: >> > neighbour: arp_cache: neighbor table overflow! >> > >> > Alan's mpls script helped get to the bottom of this bug. When a new entry >> > is created the gc_entries counter is bumped in neigh_alloc to check if a >> > new one is allowed to be created. ___neigh_create then searches for an >> > existing entry before inserting the just allocated one. If an entry >> > already exists, the new one is dropped in favor of the existing one. In >> > this case the cleanup path needs to drop the gc_entries counter. There >> > is no memory leak, only a counter leak. >> > >> > Fixes: 58956317c8d ("neighbor: Improve garbage collection") >> > Reported-by: Ian Kumlien >> > Reported-by: Alan Maguire >> > Signed-off-by: David Ahern >> >> Applied and queued up for -stable. > > Did this get lost in the shuffle? I see it in mainline, but I don't see > it in stable. Folks are encountering it with recent 5.1 kernels in > Fedora: https://bugzilla.redhat.com/show_bug.cgi?id=1708717. It's there in the -stable queue: https://patchwork.ozlabs.org/bundle/davem/stable/?series=&submitter=&state=*&q=&archive= So it will (eventually) get sent.