1 files changed, 43 insertions, 52 deletions

diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index dd611ef8df7a..7d6ebe3c3b9b 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -191,27 +191,28 @@ static int *of_get_associativity(struct device_node *dev)
         return (unsigned int *)get_property(dev, "ibm,associativity", NULL);
 }
 
+/* Returns nid in the range [0..MAX_NUMNODES-1], or -1 if no useful numa
+ * info is found.
+ */
 static int of_node_to_nid(struct device_node *device)
 {
-        int nid;
+        int nid = -1;
         unsigned int *tmp;
 
         if (min_common_depth == -1)
-                return 0;
+                goto out;
 
         tmp = of_get_associativity(device);
-        if (tmp && (tmp[0] >= min_common_depth)) {
+        if (!tmp)
+                goto out;
+
+        if (tmp[0] >= min_common_depth)
                 nid = tmp[min_common_depth];
-        } else {
-                dbg("WARNING: no NUMA information for %s\n",
-                    device->full_name);
-                nid = 0;
-        }
 
         /* POWER4 LPAR uses 0xffff as invalid node */
-        if (nid == 0xffff)
-                nid = 0;
-
+        if (nid == 0xffff || nid >= MAX_NUMNODES)
+                nid = -1;
+out:
         return nid;
 }
 
@@ -301,15 +302,9 @@ static int __cpuinit numa_setup_cpu(unsigned long lcpu)
 
         nid = of_node_to_nid(cpu);
 
-        if (nid >= num_online_nodes()) {
-                printk(KERN_ERR "WARNING: cpu %ld "
-                       "maps to invalid NUMA node %d\n",
-                       lcpu, nid);
-                nid = 0;
-        }
+        if (nid < 0 || !node_online(nid))
+                nid = any_online_node(NODE_MASK_ALL);
 out:
-        node_set_online(nid);
-
         map_cpu_to_node(lcpu, nid);
 
         of_node_put(cpu);
@@ -376,7 +371,7 @@ static int __init parse_numa_properties(void)
 {
         struct device_node *cpu = NULL;
         struct device_node *memory = NULL;
-        int max_domain = 0;
+        int default_nid = 0;
         unsigned long i;
 
         if (numa_enabled == 0) {
@@ -392,25 +387,26 @@ static int __init parse_numa_properties(void)
         dbg("NUMA associativity depth for CPU/Memory: %d\n", min_common_depth);
 
         /*
-         * Even though we connect cpus to numa domains later in SMP init,
-         * we need to know the maximum node id now. This is because each
-         * node id must have NODE_DATA etc backing it.
-         * As a result of hotplug we could still have cpus appear later on
-         * with larger node ids. In that case we force the cpu into node 0.
+         * Even though we connect cpus to numa domains later in SMP
+         * init, we need to know the node ids now. This is because
+         * each node to be onlined must have NODE_DATA etc backing it.
          */
-        for_each_cpu(i) {
+        for_each_present_cpu(i) {
                 int nid;
 
                 cpu = find_cpu_node(i);
+                BUG_ON(!cpu);
+                nid = of_node_to_nid(cpu);
+                of_node_put(cpu);
 
-                if (cpu) {
-                        nid = of_node_to_nid(cpu);
-                        of_node_put(cpu);
-
-                        if (nid < MAX_NUMNODES &&
-                            max_domain < nid)
-                                max_domain = nid;
-                }
+                /*
+                 * Don't fall back to default_nid yet -- we will plug
+                 * cpus into nodes once the memory scan has discovered
+                 * the topology.
+                 */
+                if (nid < 0)
+                        continue;
+                node_set_online(nid);
         }
 
         get_n_mem_cells(&n_mem_addr_cells, &n_mem_size_cells);
@@ -439,17 +435,15 @@ new_range:
                 start = read_n_cells(n_mem_addr_cells, &memcell_buf);
                 size = read_n_cells(n_mem_size_cells, &memcell_buf);
 
+                /*
+                 * Assumption: either all memory nodes or none will
+                 * have associativity properties.  If none, then
+                 * everything goes to default_nid.
+                 */
                 nid = of_node_to_nid(memory);
-
-                if (nid >= MAX_NUMNODES) {
-                        printk(KERN_ERR "WARNING: memory at %lx maps "
-                               "to invalid NUMA node %d\n", start,
-                               nid);
-                        nid = 0;
-                }
-
-                if (max_domain < nid)
-                        max_domain = nid;
+                if (nid < 0)
+                        nid = default_nid;
+                node_set_online(nid);
 
                 if (!(size = numa_enforce_memory_limit(start, size))) {
                         if (--ranges)
@@ -465,10 +459,7 @@ new_range:
                         goto new_range;
         }
 
-        for (i = 0; i <= max_domain; i++)
-                node_set_online(i);
-
-        max_domain = numa_setup_cpu(boot_cpuid);
+        numa_setup_cpu(boot_cpuid);
 
         return 0;
 }
@@ -768,10 +759,10 @@ int hot_add_scn_to_nid(unsigned long scn_addr)
 {
         struct device_node *memory = NULL;
         nodemask_t nodes;
-        int nid = 0;
+        int default_nid = any_online_node(NODE_MASK_ALL);
 
         if (!numa_enabled || (min_common_depth < 0))
-                return nid;
+                return default_nid;
 
         while ((memory = of_find_node_by_type(memory, "memory")) != NULL) {
                 unsigned long start, size;
@@ -791,8 +782,8 @@ ha_new_range:
                 nid = of_node_to_nid(memory);
 
                 /* Domains not present at boot default to 0 */
-                if (!node_online(nid))
-                        nid = any_online_node(NODE_MASK_ALL);
+                if (nid < 0 || !node_online(nid))
+                        nid = default_nid;
 
                 if ((scn_addr >= start) && (scn_addr < (start + size))) {
                         of_node_put(memory);