Re: unregister_netdevice: waiting for eth0 to become free. Usage count = 1

(Cc'ing Wei whose commit was blamed)

On Mon, Aug 7, 2017 at 2:15 PM, John Stultz [off-list ref] wrote:

On Mon, Aug 7, 2017 at 2:05 PM, John Stultz [off-list ref] wrote:

quoted

So, with recent testing with my HiKey board, I've been noticing some
quirky behavior with my USB eth adapter.

Basically, pluging the usb eth adapter in and then removing it, when
plugging it back in I often find that its not detected, and the system
slowly spits out the following message over and over:
  unregister_netdevice: waiting for eth0 to become free. Usage count = 1

The other bit is that after this starts printing, the board will no
longer reboot (it hangs continuing to occasionally print the above
message), and I have to manually reset the device.

So this warning is not temporarily shown but lasts until a reboot,
right? If so it is a dst refcnt leak.

How reproducible is it for you? From my reading, it seems always
reproduced when you unplug and plug your usb eth interface?
Is there anything else involved? For example, network namespace.

Thanks.