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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id B67F5C433F5 for ; Mon, 6 Dec 2021 23:24:08 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376617AbhLFX1g (ORCPT ); Mon, 6 Dec 2021 18:27:36 -0500 Received: from vps0.lunn.ch ([185.16.172.187]:41770 "EHLO vps0.lunn.ch" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1347405AbhLFX1f (ORCPT ); Mon, 6 Dec 2021 18:27:35 -0500 DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lunn.ch; s=20171124; h=In-Reply-To:Content-Disposition:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:From:Sender:Reply-To:Subject: Date:Message-ID:To:Cc:MIME-Version:Content-Type:Content-Transfer-Encoding: Content-ID:Content-Description:Content-Disposition:In-Reply-To:References; bh=X1OCibj2j+vUU+pRdKucv2D/GSCJAocjZ9wPf39Y1Us=; b=ykHK84BHlvzWkcO++YNIWviQzU uDAnQ8/xLJ/IWl6QKRCE9rzJdLgT2axl3Ozf+BaD+7y4l3hq3YgY2BDLKVi5DypxmVyrzpKN+odnL 6O3nLRA01MNMvtzzMLXMxC6keBUYlD62sbpVWhXTHDalHk/lRMRaMkfO6+j2MgMkkSuI=; Received: from andrew by vps0.lunn.ch with local (Exim 4.94.2) (envelope-from ) id 1muNKx-00FiZ8-97; Tue, 07 Dec 2021 00:23:59 +0100 Date: Tue, 7 Dec 2021 00:23:59 +0100 From: Andrew Lunn To: Eric Dumazet Cc: "David S . Miller" , Jakub Kicinski , netdev , Eric Dumazet , Dmitry Vyukov Subject: Re: [PATCH v3 net-next 00/23] net: add preliminary netdev refcount tracking Message-ID: References: <20211205042217.982127-1-eric.dumazet@gmail.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211205042217.982127-1-eric.dumazet@gmail.com> Precedence: bulk List-ID: X-Mailing-List: netdev@vger.kernel.org On Sat, Dec 04, 2021 at 08:21:54PM -0800, Eric Dumazet wrote: > From: Eric Dumazet > > Two first patches add a generic infrastructure, that will be used > to get tracking of refcount increments/decrements. Hi Eric Using this i found: [ 774.108901] unregister_netdevice: waiting for eth0 to become free. Usage count = 4 [ 774.110864] leaked reference. [ 774.110874] dst_alloc+0x7a/0x180 [ 774.110887] ip6_dst_alloc+0x27/0x90 [ 774.110894] ip6_pol_route+0x257/0x430 [ 774.110900] ip6_pol_route_output+0x19/0x20 [ 774.110905] fib6_rule_lookup+0x18b/0x270 [ 774.110914] ip6_route_output_flags_noref+0xaa/0x110 [ 774.110918] ip6_route_output_flags+0x32/0xa0 [ 774.110922] ip6_dst_lookup_tail.constprop.0+0x181/0x240 [ 774.110929] ip6_dst_lookup_flow+0x43/0xa0 [ 774.110934] inet6_csk_route_socket+0x166/0x200 [ 774.110943] inet6_csk_xmit+0x56/0x130 [ 774.110946] __tcp_transmit_skb+0x53b/0xc30 [ 774.110953] __tcp_send_ack.part.0+0xc6/0x1a0 [ 774.110958] tcp_send_ack+0x1c/0x20 [ 774.110964] __tcp_ack_snd_check+0x42/0x200 [ 774.110968] tcp_rcv_established+0x27a/0x6f0 [ 774.110973] leaked reference. [ 774.110975] ipv6_add_dev+0x13e/0x4f0 [ 774.110982] addrconf_notify+0x2ca/0x950 [ 774.110989] raw_notifier_call_chain+0x49/0x60 [ 774.111000] call_netdevice_notifiers_info+0x50/0x90 [ 774.111007] __dev_change_net_namespace+0x30d/0x6c0 [ 774.111016] do_setlink+0xdc/0x10b0 [ 774.111024] __rtnl_newlink+0x608/0xa10 [ 774.111031] rtnl_newlink+0x49/0x70 [ 774.111038] rtnetlink_rcv_msg+0x14f/0x380 [ 774.111046] netlink_rcv_skb+0x55/0x100 [ 774.111053] rtnetlink_rcv+0x15/0x20 [ 774.111059] netlink_unicast+0x230/0x340 [ 774.111064] netlink_sendmsg+0x252/0x4b0 [ 774.111075] sock_sendmsg+0x65/0x70 [ 774.111080] ____sys_sendmsg+0x24e/0x290 [ 774.111084] ___sys_sendmsg+0x81/0xc0 I'm using GNS3 to simulate a network topology. So a collection of veth pairs, bridges and tap interfaces spread over a few namespaces. The network being simulated uses Segment Routing. And traceroute might also involved in this somehow. I have 3 patches applied, to make traceroute actually work when SRv6 is being used. You can find v3 here: https://lore.kernel.org/netdev/20211203162926.3680281-3-andrew@lunn.ch/T/ I'm not sure if these patches are part of the problem or not. None of the traces i've seen are directly on the ICMP path. traceroute is using udp, and one of the traces above is for tcp, and the other looks like it is moving an interface into a different namespace? This is net-next from today. Any ideas? Thanks Andrew