diff --git a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
index c33a0d2296..555f294761 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
+++ b/hadoop-hdfs-project/hadoop-hdfs/CHANGES.txt
@@ -587,6 +587,9 @@ Release 2.6.0 - UNRELEASED
 
     HDFS-6942. Fix typos in log messages. (Ray Chiang via wheat9)
 
+      HDFS-6848. Lack of synchronization on access to datanodeUuid in
+      DataStorage#format(). (Xiaoyu Yao via Arpit Agarwal)
+
     BREAKDOWN OF HDFS-6134 AND HADOOP-10150 SUBTASKS AND RELATED JIRAS
   
       HDFS-6387. HDFS CLI admin tool for creating & deleting an
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataStorage.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataStorage.java
index ceb2aa0795..f382a9e7eb 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataStorage.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/hdfs/server/datanode/DataStorage.java
@@ -463,7 +463,7 @@ void format(StorageDirectory sd, NamespaceInfo nsInfo,
     this.clusterID = nsInfo.getClusterID();
     this.namespaceID = nsInfo.getNamespaceID();
     this.cTime = 0;
-    this.datanodeUuid = datanodeUuid;
+    setDatanodeUuid(datanodeUuid);
 
     if (sd.getStorageUuid() == null) {
       // Assign a new Storage UUID.