I am able to reliably recreate this on both Ubuntu 14.04 with kernel 3.13.0-37-generic and Ubuntu 14.10 with kernel 3.16.0-23-generic. I have test code that can hit the bug, but it's not cleaned up enough to share. The steps to repro are:
Start a container (COW clone using overlayfs from a base/parent Ubuntu 14.04 container). Start clone container, mount an NFS share (remote from machine hosting container) to /mnt in container, create a file on the NFS share in container (dd if=/dev/zero of=/mnt/foo bs=1024 count=100000), stop container, destroy container. I have a script that performs the above sequence over and over again, running 5 such clone containers in parallel at any given time. It only takes about 30s for the kernel to get wedged with: unregister_netdevice: waiting for lo to become free. Usage count = 1 This same script is fine if you do scp instead of writing over NFS. It seems like NFS inside the container is somehow involved here. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1403152 Title: unregister_netdevice: waiting for lo to become free. Usage count To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/1403152/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
