In case of error during netback_probe() (e.g. an entry missing on the xenstore) netback_remove() is called on the new device, which will set the device backend state to XenbusStateClosed by calling set_backend_state(). However, the backend state wasn't initialized by netback_probe() at this point, which will cause and invalid transaction and set_backend_state() to BUG(). Initialize the backend state at the beginning of netback_probe() to XenbusStateInitialising, and create two new valid state transitions on set_backend_state(), from XenbusStateInitialising to XenbusStateClosed, and from XenbusStateInitialising to XenbusStateInitWait. Signed-off-by: Filipe Manco <filipe.manco@neclab.eu> Acked-by: Wei Liu <wei.liu2@citrix.com> Signed-off-by: David S. Miller <davem@davemloft.net>