bug_on
bug_on(1);
bug_on(ring->type != PACKET_RX_RING);
bug_on(1);
bug_on(1);
bug_on(ring->type != PACKET_TX_RING);
bug_on(nframes < NUM_PACKETS);
bug_on(total_packets != 0);
#ifndef bug_on
bug_on(ring->type != PACKET_RX_RING);