[PATCH] powerpc/cell spidernet incorrect offset

Bugfix -- the rx chain is in memory after the tx chain --
the offset being used was wrong, resulting in memory corruption
when the size of the rx and tx rings weren't exactly the same.
Signed-off-by: NLinas Vepstas <linas@austin.ibm.com>
Cc: James K Lewis <jklewis@us.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: NJeff Garzik <jeff@garzik.org>

drivers/net/spider_net.c

@@ -1628,8 +1628,10 @@ spider_net_open(struct net_device *netdev)
 	if (spider_net_init_chain(card, &card->tx_chain, card->descr,
 			PCI_DMA_TODEVICE, card->tx_desc))
 		goto alloc_tx_failed;
+
+	/* rx_chain is after tx_chain, so offset is descr + tx_count */
 	if (spider_net_init_chain(card, &card->rx_chain,
-			card->descr + card->rx_desc,
+			card->descr + card->tx_desc,
 			PCI_DMA_FROMDEVICE, card->rx_desc))
 		goto alloc_rx_failed;