From 585d9335d05714eca29a8a35520a9ba5bb01d921 Mon Sep 17 00:00:00 2001
From: Tang Chen <tangchen@cn.fujitsu.com>
Date: Fri, 22 Feb 2013 16:33:18 -0800
Subject: [PATCH] --- yaml --- r: 356525 b: refs/heads/master c:
 a1e565aa3cfc7c6252cabc93de8391d12b9216aa h: refs/heads/master i:   356523:
 8f220b3c1a99aad5ce1bb17662d94ee7a09a1f9d v: v3

---
 [refs]                    |  2 +-
 trunk/mm/memory_hotplug.c | 24 ++++++++++++++++--------
 2 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/[refs] b/[refs]
index c8441599469c..05c369ce5a84 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: d822b86a99e8d2b7ebbe3aba099288354287a885
+refs/heads/master: a1e565aa3cfc7c6252cabc93de8391d12b9216aa
diff --git a/trunk/mm/memory_hotplug.c b/trunk/mm/memory_hotplug.c
index 3409134ff20a..e189b1f4a9db 100644
--- a/trunk/mm/memory_hotplug.c
+++ b/trunk/mm/memory_hotplug.c
@@ -1017,11 +1017,14 @@ static pg_data_t __ref *hotadd_new_pgdat(int nid, u64 start)
 	unsigned long zholes_size[MAX_NR_ZONES] = {0};
 	unsigned long start_pfn = start >> PAGE_SHIFT;
 
-	pgdat = arch_alloc_nodedata(nid);
-	if (!pgdat)
-		return NULL;
+	pgdat = NODE_DATA(nid);
+	if (!pgdat) {
+		pgdat = arch_alloc_nodedata(nid);
+		if (!pgdat)
+			return NULL;
 
-	arch_refresh_nodedata(nid, pgdat);
+		arch_refresh_nodedata(nid, pgdat);
+	}
 
 	/* we can use NODE_DATA(nid) from here */
 
@@ -1074,7 +1077,8 @@ int mem_online_node(int nid)
 int __ref add_memory(int nid, u64 start, u64 size)
 {
 	pg_data_t *pgdat = NULL;
-	int new_pgdat = 0;
+	bool new_pgdat;
+	bool new_node;
 	struct resource *res;
 	int ret;
 
@@ -1085,12 +1089,16 @@ int __ref add_memory(int nid, u64 start, u64 size)
 	if (!res)
 		goto out;
 
-	if (!node_online(nid)) {
+	{	/* Stupid hack to suppress address-never-null warning */
+		void *p = NODE_DATA(nid);
+		new_pgdat = !p;
+	}
+	new_node = !node_online(nid);
+	if (new_node) {
 		pgdat = hotadd_new_pgdat(nid, start);
 		ret = -ENOMEM;
 		if (!pgdat)
 			goto error;
-		new_pgdat = 1;
 	}
 
 	/* call arch's memory hotadd */
@@ -1102,7 +1110,7 @@ int __ref add_memory(int nid, u64 start, u64 size)
 	/* we online node here. we can't roll back from here. */
 	node_set_online(nid);
 
-	if (new_pgdat) {
+	if (new_node) {
 		ret = register_one_node(nid);
 		/*
 		 * If sysfs file of new node can't create, cpu on the node