NPE while processing onArpPacketReceived yang notification

I see following NPE exception in my environment and when this exception occur yang notification stops working.

2016-03-21 10:29:59,040 | ERROR | pool-30-thread-1 | FatalExceptionHandler | 131 - com.lmax.disruptor - 3.3.0 | Exception processing: 26 org.opendaylight.controller.md.sal.dom.broker.impl.DOMNotificationRouterEvent@5616b3b9
java.lang.NullPointerException
at org.opendaylight.l2switch.arphandler.inventory.InventoryReader.getNodeConnector(InventoryReader.java:160)
at org.opendaylight.l2switch.arphandler.core.PacketDispatcher.dispatchPacket(PacketDispatcher.java:63)
at org.opendaylight.l2switch.arphandler.core.ArpPacketHandler.onArpPacketReceived(ArpPacketHandler.java:58)
at org.opendaylight.yangtools.yang.binding.util.NotificationListenerInvoker.invokeNotification(NotificationListenerInvoker.java:91)[48:org.opendaylight.yangtools.yang-binding:0.7.3.Lithium-SR3]
at org.opendaylight.controller.md.sal.binding.impl.BindingDOMNotificationListenerAdapter.onNotification(BindingDOMNotificationListenerAdapter.java:44)[137:org.opendaylight.controller.sal-binding-broker-impl:1.2.3.Lithium-SR3]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMNotificationRouterEvent.deliverNotification(DOMNotificationRouterEvent.java:50)[134:org.opendaylight.controller.sal-broker-impl:1.2.3.Lithium-SR3]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMNotificationRouter$1.onEvent(DOMNotificationRouter.java:68)[134:org.opendaylight.controller.sal-broker-impl:1.2.3.Lithium-SR3]
at org.opendaylight.controller.md.sal.dom.broker.impl.DOMNotificationRouter$1.onEvent(DOMNotificationRouter.java:65)[134:org.opendaylight.controller.sal-broker-impl:1.2.3.Lithium-SR3]
at com.lmax.disruptor.BatchEventProcessor.run(BatchEventProcessor.java:128)[131:com.lmax.disruptor:3.3.0]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)[:1.7.0_95]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)[:1.7.0_95]
at java.lang.Thread.run(Thread.java:745)[:1.7.0_95]

This exception eventually shutdown the DOMNotificationRouter thread pool and it doesn't route any yang notification.