Hi Eric,

On Thu, Jun 01, 2017 at 01:32:49AM -0500, Eric W. Biederman wrote:

If a network device does not implement rntl_link_ops it is returned to
the initial network namespace.   Anything else will loose physical
devices.

Thanks a lot for your statement.  This is a big relief, my line of
thinking thus is confirmed:  We shall not loose physical devices.

Only for pure software based devices do we delete them.  Perhaps your
sub interface implements rtnl_link_ops?  Either that or something is
still holding a reference to your network namespace, which would prevent
the network device from being returned.

My question is how to debug this further?  Monitoring
/proc/*/ns/net* showed that the ID of the namespace is gone after
terminating my processes in the namespace.  Short of adding printk() or
playing with kprobes: to the related kernel code, how can I track the
reference count or get an idea who might hold references?

Regards,
	Harald
-- 
- Harald Welte [off-list ref]           http://laforge.gnumonks.org/
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