What is the upside for North Korea here?

So, North Korea is now using artillery against South Korean civilians.  (Telegraph)  I'm not sure what they could possibly think will come of this, outside of even more of their population starving to death as the international community further withdraws aid.  Possibly the internal situation is now so bad that only being at war will prevent internal rebellion?  I hope not, but the whole thing is moving from farcical to absurd.