diff --git a/[refs] b/[refs]
index 725981532723..12013b71ee6b 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 0815f3d81d76dfbf2abcfd93a85ff0a6008fe4c0
+refs/heads/master: cfd3da1e49bb95c355c01c0f502d657deb3d34a4
diff --git a/trunk/mm/page_alloc.c b/trunk/mm/page_alloc.c
index 116c087f76bb..8be37bcda0b2 100644
--- a/trunk/mm/page_alloc.c
+++ b/trunk/mm/page_alloc.c
@@ -5020,14 +5020,7 @@ static void setup_per_zone_lowmem_reserve(void)
 	calculate_totalreserve_pages();
 }
 
-/**
- * setup_per_zone_wmarks - called when min_free_kbytes changes
- * or when memory is hot-{added|removed}
- *
- * Ensures that the watermark[min,low,high] values for each zone are set
- * correctly with respect to min_free_kbytes.
- */
-void setup_per_zone_wmarks(void)
+static void __setup_per_zone_wmarks(void)
 {
 	unsigned long pages_min = min_free_kbytes >> (PAGE_SHIFT - 10);
 	unsigned long lowmem_pages = 0;
@@ -5082,6 +5075,20 @@ void setup_per_zone_wmarks(void)
 	calculate_totalreserve_pages();
 }
 
+/**
+ * setup_per_zone_wmarks - called when min_free_kbytes changes
+ * or when memory is hot-{added|removed}
+ *
+ * Ensures that the watermark[min,low,high] values for each zone are set
+ * correctly with respect to min_free_kbytes.
+ */
+void setup_per_zone_wmarks(void)
+{
+	mutex_lock(&zonelists_mutex);
+	__setup_per_zone_wmarks();
+	mutex_unlock(&zonelists_mutex);
+}
+
 /*
  * The inactive anon list should be small enough that the VM never has to
  * do too much work, but large enough that each inactive page has a chance