r8169: fix infinite loop during hotplug

Bug reported for PCMCIA.

Signed-off-by: Arnaud Patard <apatard@mandriva.com>
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
diff --git a/drivers/net/r8169.c b/drivers/net/r8169.c
index c7309e9..c2c9a86 100644
--- a/drivers/net/r8169.c
+++ b/drivers/net/r8169.c
@@ -2702,6 +2702,7 @@
 	struct rtl8169_private *tp = netdev_priv(dev);
 	void __iomem *ioaddr = tp->mmio_addr;
 	unsigned int poll_locked = 0;
+	unsigned int intrmask;
 
 	rtl8169_delete_timer(dev);
 
@@ -2740,8 +2741,11 @@
 	 * 2) dev->change_mtu
 	 *    -> rtl8169_poll can not be issued again and re-enable the
 	 *       interruptions. Let's simply issue the IRQ down sequence again.
+	 *
+	 * No loop if hotpluged or major error (0xffff).
 	 */
-	if (RTL_R16(IntrMask))
+	intrmask = RTL_R16(IntrMask);
+	if (intrmask && (intrmask != 0xffff))
 		goto core_down;
 
 	rtl8169_tx_clear(tp);