Index: madwifi-trunk-r3776/ath/if_ath.c
===================================================================
--- madwifi-trunk-r3776.orig/ath/if_ath.c	2008-07-17 00:52:28.000000000 +0200
+++ madwifi-trunk-r3776/ath/if_ath.c	2008-07-17 00:53:04.000000000 +0200
@@ -6451,9 +6451,6 @@
 		rs = &bf->bf_dsstatus.ds_rxstat;
 
 		len = rs->rs_datalen;
-		/* DMA sync. dies spectacularly if len == 0 */
-		if (len == 0)
-			goto rx_next;
 		if (rs->rs_more) {
 			/* Frame spans multiple descriptors; this
 			 * cannot happen yet as we don't support
@@ -6513,8 +6510,12 @@
 		 * setup again to receive another frame. 
 		 * NB: Meta-data (rs, noise, tsf) in the ath_buf is still
 		 * used. */
-		bus_dma_sync_single(sc->sc_bdev,
-			bf->bf_skbaddr, len, BUS_DMA_FROMDEVICE);
+
+		/* DMA sync. dies spectacularly if len == 0 */
+		if (len != 0) {
+			bus_dma_sync_single(sc->sc_bdev,
+				bf->bf_skbaddr, len, BUS_DMA_FROMDEVICE);
+		}
 		skb = ath_rxbuf_take_skb(sc, bf);
 
 		sc->sc_stats.ast_ant_rx[rs->rs_antenna]++;