[PATCH] e1000: disable TSO on the 82544 with slab debugging

CONFIG_DEBUG_SLAB changes alignments of the data structures the slab
allocators return. These break certain workarounds for TSO on the 82544.
Since DEBUG_SLAB is relatively rare and not used for performance sensitive
cases, the simplest fix is to disable TSO in this special situation.

Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Signed-off-by: Auke Kok <auke-jan.h.kok@intel.com>
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

drivers/net/e1000/e1000_main.c

@@ -911,6 +911,12 @@ e1000_probe(struct pci_dev *pdev,
 	   (adapter->hw.mac_type != e1000_82547))
 		netdev->features |= NETIF_F_TSO;
 
+#ifdef CONFIG_DEBUG_SLAB
+	/* 82544's work arounds do not play nicely with DEBUG SLAB */
+	if (adapter->hw.mac_type == e1000_82544)
+		netdev->features &= ~NETIF_F_TSO;
+#endif
+
 #ifdef NETIF_F_TSO6
 	if (adapter->hw.mac_type > e1000_82547_rev_2)
 		netdev->features |= NETIF_F_TSO6;