Hi, In a test-setup I can easily reproduce this issue very quickly. At my scenario it looks like the issue is just triggered if I change the IP inside the docker container (Needed to test StrongSwan's MOBIKE feature), send some data (ICMP) and then kill the docker container.
So if there is something to test or debug, I would be happy to help fixing this issue. Also already tried the latest kernel from http://kernel.ubuntu.com/~kernel-ppa/mainline/: Linux docker 4.15.0-041500rc3-generic #201712110230 SMP Mon Dec 11 02:31:13 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1711407 Title: unregister_netdevice: waiting for lo to become free Status in linux package in Ubuntu: In Progress Status in linux source package in Trusty: In Progress Status in linux source package in Xenial: In Progress Status in linux source package in Zesty: In Progress Status in linux source package in Artful: In Progress Status in linux source package in Bionic: In Progress Bug description: This is a "continuation" of bug 1403152, as that bug has been marked "fix released" and recent reports of failure may (or may not) be a new bug. Any further reports of the problem should please be reported here instead of that bug. -- [Impact] When shutting down and starting containers the container network namespace may experience a dst reference counting leak which results in this message repeated in the logs: unregister_netdevice: waiting for lo to become free. Usage count = 1 This can cause issues when trying to create net network namespace and thus block a user from creating new containers. [Test Case] See comment 16, reproducer provided at https://github.com/fho/docker- samba-loop To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1711407/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp