sky2: MIB counter overflow handling

Make sure that if we ever get a MIB counter overflow interrupt (normally
masked off), that the IRQ is cleared.

Signed-off-by: Stephen Hemminger <shemminger@linux-foundation.org>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/sky2.c

@@ -2345,6 +2345,12 @@ static void sky2_mac_intr(struct sky2_hw *hw, unsigned port)
 		printk(KERN_INFO PFX "%s: mac interrupt status 0x%x\n",
 		       dev->name, status);
 
+	if (status & GM_IS_RX_CO_OV)
+		gma_read16(hw, port, GM_RX_IRQ_SRC);
+
+	if (status & GM_IS_TX_CO_OV)
+		gma_read16(hw, port, GM_TX_IRQ_SRC);
+
 	if (status & GM_IS_RX_FF_OR) {
 		++sky2->net_stats.rx_fifo_errors;
 		sky2_write8(hw, SK_REG(port, RX_GMF_CTRL_T), GMF_CLI_RX_FO);