1 files changed, 25 insertions, 0 deletions

diff --git a/kernel/cpu.c b/kernel/cpu.c
index 545777574779..a3fbcc0a0abc 100644
--- a/kernel/cpu.c
+++ b/kernel/cpu.c
@@ -326,6 +326,12 @@ out_notify:
 int __cpuinit cpu_up(unsigned int cpu)
 {
         int err = 0;
+
+#ifdef  CONFIG_MEMORY_HOTPLUG
+        int nid;
+        pg_data_t       *pgdat;
+#endif
+
         if (!cpu_possible(cpu)) {
                 printk(KERN_ERR "can't online cpu %d because it is not "
                         "configured as may-hotadd at boot time\n", cpu);
@@ -336,6 +342,25 @@ int __cpuinit cpu_up(unsigned int cpu)
                 return -EINVAL;
         }
 
+#ifdef  CONFIG_MEMORY_HOTPLUG
+        nid = cpu_to_node(cpu);
+        if (!node_online(nid)) {
+                err = mem_online_node(nid);
+                if (err)
+                        return err;
+        }
+
+        pgdat = NODE_DATA(nid);
+        if (!pgdat) {
+                printk(KERN_ERR
+                        "Can't online cpu %d due to NULL pgdat\n", cpu);
+                return -ENOMEM;
+        }
+
+        if (pgdat->node_zonelists->_zonerefs->zone == NULL)
+                build_all_zonelists();
+#endif
+
         cpu_maps_update_begin();
 
         if (cpu_hotplug_disabled) {