From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andre Tomt Subject: 2.6.10 ipv6/8021q lockup on vconfig on interface removal Date: Sun, 16 Jan 2005 07:30:25 +0100 Message-ID: <41EA0A01.2020707@tomt.net> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Return-path: To: netdev@oss.sgi.com Sender: netdev-bounce@oss.sgi.com Errors-to: netdev-bounce@oss.sgi.com List-Id: netdev.vger.kernel.org I sent this initially about a week ago, but nobody have said anything, not even a confirmation that its beeing looked into, or about me beeing silly - highly unusual on netdev! So I'm reposting (with slight modifications), boo, shame on me. Just a bit worried it slipped through the cracks. Hi! Another "unregister_netdevice: waiting for eth0.1 to become free. Usage count = 1" issue coming up.. Fun fun fun! And this one also seems to be related to the ipv6 stack. I can reproduce this reliably this by ifdown lo before ifdown'ing eth0.1. That is, if lo goes down first, vconfig rem eth0.1 gets stuck when run later. This only happens with ipv6.ko loaded. I havn't added *any* ipv6 adresses to any interace, the only one are those the ipv6-stack adds itself. This is hitting us often on our routers, as we have ipv6.ko loaded, and Debian runs ifdown -a (bring down all configured interfaces, starting with lo unfortunatly) on shutdown and reboot. I've currently workarounded the problem by making sure ifdown -a is not run on reboot or shutdown, but this is, well, a workaround. Bringing down non-vlan interfaces works just fine after killing lo. I have not attempted to *remove* them like vconfig does, though. a backtrace from vconfing captured with sysrq-T (quickly typed off-screen): shedule_timeout process_timeout netdev_wait_allrefs netdev_wait_allrefs netdev_run_todo unregister_vlan_device [8021q] vlan_ioctl_handler [8021q] sock_ioctl sys_ioctl syscall_call The lab machine is running with a minimalist config, no listeners besides sshd, ipv6.ko and 8021q.ko loaded.