[PATCH] x86-64: Don't enable NUMA for a single node in K8 NUMA scanning

This was supposed to see the full memory on a ASUS A8SX motherboard
with 4GB RAM where the northbridge reports less memory, but it didn't
help there. But it's a reasonable change so let's include it anyways.

Signed-off-by: Andi Kleen <ak@suse.de>

arch/x86_64/mm/k8topology.c

@@ -62,6 +62,8 @@ int __init k8_scan_nodes(unsigned long start, unsigned long end)
 
 	reg = read_pci_config(0, nb, 0, 0x60); 
 	numnodes = ((reg >> 4) & 0xF) + 1;
+	if (numnodes <= 1)
+		return -1;
 
 	printk(KERN_INFO "Number of nodes %d\n", numnodes);