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_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 8DC61C43381 for ; Fri, 22 Feb 2019 19:46:33 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 5FF6D2077B for ; Fri, 22 Feb 2019 19:46:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726557AbfBVTqc (ORCPT ); Fri, 22 Feb 2019 14:46:32 -0500 Received: from shards.monkeyblade.net ([23.128.96.9]:57124 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1725917AbfBVTqb (ORCPT ); Fri, 22 Feb 2019 14:46:31 -0500 Received: from localhost (unknown [IPv6:2601:601:9f80:35cd::bf5]) (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 507B614A8E429; Fri, 22 Feb 2019 11:46:30 -0800 (PST) Date: Fri, 22 Feb 2019 11:46:29 -0800 (PST) Message-Id: <20190222.114629.1475722353193768939.davem@davemloft.net> To: pabeni@redhat.com Cc: netdev@vger.kernel.org, dsahern@gmail.com Subject: Re: [PATCH net v2] ipv6: route: purge exception on removal From: David Miller In-Reply-To: <1cf1aef01dd9294347df6e339d2f8f042172fb54.1550679150.git.pabeni@redhat.com> References: <1cf1aef01dd9294347df6e339d2f8f042172fb54.1550679150.git.pabeni@redhat.com> 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]); Fri, 22 Feb 2019 11:46:30 -0800 (PST) Sender: netdev-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org From: Paolo Abeni Date: Wed, 20 Feb 2019 18:18:12 +0100 > When a netdevice is unregistered, we flush the relevant exception > via rt6_sync_down_dev() -> fib6_ifdown() -> fib6_del() -> fib6_del_route(). > > Finally, we end-up calling rt6_remove_exception(), where we release > the relevant dst, while we keep the references to the related fib6_info and > dev. Such references should be released later when the dst will be > destroyed. > > There are a number of caches that can keep the exception around for an > unlimited amount of time - namely dst_cache, possibly even socket cache. > As a result device registration may hang, as demonstrated by this script: ... > Fixes: 93531c674315 ("net/ipv6: separate handling of FIB entries from dst based routes") > Signed-off-by: Paolo Abeni Applied and queued up for -stable, thanks.