Re: [Bugme-new] [Bug 30082] New: after lxc-stop: unregister_netdevice: waiting for lo to become free. Usage count: 3

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On Mon, 28 Feb 2011 14:47:03 GMT
bugzilla-daemon@bugzilla.kernel.org wrote:

https://bugzilla.kernel.org/show_bug.cgi?id=30082

           Summary: after lxc-stop: unregister_netdevice: waiting for lo
                    to become free. Usage count: 3
           Product: Networking
           Version: 2.5
    Kernel Version: 2.6.36 2.6.37
          Platform: All
        OS/Version: Linux
              Tree: Mainline
            Status: NEW
          Severity: normal
          Priority: P1
         Component: Other
        AssignedTo: acme@ghostprotocols.net
        ReportedBy: mjt@tls.msk.ru
        Regression: No


As far as I can tell so far this is triggered by lxc version 0.7.4, at least I
haven't seen this before.  I tried 2.6.36[.3] and 2.6.37[.2] kernels so far,
both behaves similarly.

The problem is, when I shut down a container which uses bridged veth interface
pair using lxc-stop, the container terminates, but host system starts crying
about unregister_netdevice like this:

[902885.096462] unregister_netdevice: waiting for lo to become free. Usage
count = 3
[902895.229785] unregister_netdevice: waiting for lo to become free. Usage
count = 3
[...]
[904247.123002] unregister_netdevice: waiting for lo to become free. Usage
count = 3

After some, random, time, this stops - sometimes after just one message,
sometimes after several minutes.  Sometimes it does not happen at all.

This looks like a kernel issue triggerable by lxc-0.7.4.