diff -r 13d4e78ede97 tools/python/xen/xend/XendDomainInfo.py
--- a/tools/python/xen/xend/XendDomainInfo.py	Wed Jan 13 08:33:34 2010 +0000
+++ b/tools/python/xen/xend/XendDomainInfo.py	Wed Jan 13 22:55:56 2010 +0100
@@ -2724,13 +2724,12 @@
                         candidate_node_list.append(i)
                 best_node = find_relaxed_node(candidate_node_list)[0]
                 cpumask = info['node_to_cpu'][best_node]
-                cores_per_node = info['nr_cpus'] / info['nr_nodes']
-                nodes_required = (self.info['VCPUs_max'] + cores_per_node - 1) / cores_per_node
-                if nodes_required > 1:
-                    log.debug("allocating %d NUMA nodes", nodes_required)
-                    best_nodes = find_relaxed_node(filter(lambda x: x != best_node, range(0,info['nr_nodes'])))
-                    for i in best_nodes[:nodes_required - 1]:
-                        cpumask = cpumask + info['node_to_cpu'][i]
+                best_nodes = find_relaxed_node(filter(lambda x: x != best_node, range(0,info['nr_nodes'])))
+                for node_idx in best_nodes:
+                    if len(cpumask) >= self.info['VCPUs_max']:
+                        break
+                    cpumask = cpumask + info['node_to_cpu'][node_idx]
+                    log.debug("allocating additional NUMA node %d", node_idx)
                 for v in range(0, self.info['VCPUs_max']):
                     xc.vcpu_setaffinity(self.domid, v, cpumask)
         return index