ovs: do not allocate memory from offline numa node

commit 598c12d0 upstream.

When openvswitch tries allocate memory from offline numa node 0:
stats = kmem_cache_alloc_node(flow_stats_cache, GFP_KERNEL | __GFP_ZERO, 0)
It catches VM_BUG_ON(nid < 0 || nid >= MAX_NUMNODES || !node_online(nid))
[ replaced with VM_WARN_ON(!node_online(nid)) recently ] in linux/gfp.h
This patch disables numa affinity in this case.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Acked-by: Pravin B Shelar <pshelar@nicira.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Luis Henriques <luis.henriques@canonical.com>

net/openvswitch/flow_table.c

@@ -90,7 +90,8 @@ struct sw_flow *ovs_flow_alloc(void)
 
 	/* Initialize the default stat node. */
 	stats = kmem_cache_alloc_node(flow_stats_cache,
-				      GFP_KERNEL | __GFP_ZERO, 0);
+				      GFP_KERNEL | __GFP_ZERO,
+				      node_online(0) ? 0 : NUMA_NO_NODE);
 	if (!stats)
 		goto err;