Another step towards solving this. After it turned out in the upstream discussions that actually the route cache should be flushed when unregistering by doing the NETDEV_UNREGISTER_BATCH notify call, I could check to find out that this fails because the notify handler checks for dereferenced pointer that is not only not set but also not really necessary. Moving the handler around a bit should actually fix this.
** Patch added: "Iteration step 3" https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1021471/+attachment/3371401/+files/0001-net-ipv4-Always-flush-route-cache-on-unregister-batc.patch -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1021471 Title: clone() hang when creating new network namespace (dmesg show unregister_netdevice: waiting for lo to become free. Usage count = 2) To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1021471/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
