From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jiri Pirko Subject: Re: ipv6 addrconfg warn_on hit: WARN_ON(ifp->idev->valid_ll_addr_cnt < 0); Date: Thu, 16 Jan 2014 15:07:01 +0100 Message-ID: <20140116140701.GB7961@minipsycho.orion> References: <20140116135323.GA7961@minipsycho.orion> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: netdev@vger.kernel.org To: hannes@stressinduktion.org Return-path: Received: from mail-ee0-f47.google.com ([74.125.83.47]:35315 "EHLO mail-ee0-f47.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751123AbaAPOHI (ORCPT ); Thu, 16 Jan 2014 09:07:08 -0500 Received: by mail-ee0-f47.google.com with SMTP id d49so772197eek.6 for ; Thu, 16 Jan 2014 06:07:07 -0800 (PST) Content-Disposition: inline In-Reply-To: <20140116135323.GA7961@minipsycho.orion> Sender: netdev-owner@vger.kernel.org List-ID: Thu, Jan 16, 2014 at 02:53:23PM CET, jiri@resnulli.us wrote: >Hi Hannes. > >WARN_ON(ifp->idev->valid_ll_addr_cnt < 0); > >We did hit once this warning during the tests. The person who hit this >says that it was during the setup of many macvlan devices. > >I examined the code but I'm not sure how this could happen. Looks like a >race condition between addrconf_dad_completed() and addrconf_ifdown(). >Not sure how to easily resolve that though. > >Would you please take a look? > >Thanks! > >Jiri [16661.669422] Call Trace: [16661.684417] [] dump_stack+0x19/0x1b [16661.714596] [] warn_slowpath_common+0x61/0x80 [16661.748587] [] warn_slowpath_null+0x1a/0x20 [16661.780334] [] update_valid_ll_addr_cnt+0x9a/0xa0 [16661.816145] [] __ipv6_ifa_notify+0xb5/0x2e0 [16661.849222] [] addrconf_ifdown+0x21e/0x3e0 [16661.880245] [] addrconf_notify+0x5e/0x430 [16661.912233] [] ? ndisc_netdev_event+0x4e/0x100 [16661.945485] [] notifier_call_chain+0x4c/0x70 [16661.979227] [] raw_notifier_call_chain+0x16/0x20 [16662.013434] [] call_netdevice_notifiers+0x2d/0x60 [16662.051709] [] dev_close_many+0xb7/0x100 [16662.084728] [] dev_close+0x60/0x80 [16662.114689] [] dev_change_net_namespace+0x94/0x220 [16662.152638] [] do_setlink+0x83/0x9f0 [16662.183447] [] ? nla_parse+0x96/0xe0 [16662.214146] [] rtnl_newlink+0x394/0x5e0 [16662.247097] [] ? selinux_capable+0x2e/0x40 [16662.281035] [] rtnetlink_rcv_msg+0x99/0x260 [16662.313053] [] ? sock_has_perm+0x75/0x90 [16662.344678] [] ? rtnetlink_rcv+0x30/0x30 [16662.375627] [] netlink_rcv_skb+0xa9/0xc0 [16662.409066] [] rtnetlink_rcv+0x28/0x30 [16662.438982] [] netlink_unicast+0xdd/0x190 [16662.470946] [] netlink_sendmsg+0x2ff/0x730 [16662.502797] [] sock_sendmsg+0x99/0xd0 [16662.532625] [] ___sys_sendmsg+0x36c/0x380 [16662.564507] [] ? skb_dequeue+0x59/0x70 [16662.596497] [] ? handle_mm_fault+0x285/0x3a0 [16662.631456] [] ? __do_page_fault+0x1f4/0x510 [16662.666968] [] ? d_free+0x55/0x60 [16662.695923] [] ? mntput_no_expire+0x3e/0x120 [16662.731922] [] ? mntput+0x24/0x40 [16662.761353] [] ? __fput+0x183/0x270 [16662.792218] [] __sys_sendmsg+0x42/0x80 [16662.824368] [] SyS_sendmsg+0x12/0x20 [16662.855854] [] system_call_fastpath+0x16/0x1b [16662.892006] ---[ end trace 9f96f71eeb981f7e ]---