diff --git a/dev-support/smart-apply-patch.sh b/dev-support/smart-apply-patch.sh
index 4ef1e8ae37..3e7b16d974 100755
--- a/dev-support/smart-apply-patch.sh
+++ b/dev-support/smart-apply-patch.sh
@@ -39,40 +39,68 @@ fi
 # Come up with a list of changed files into $TMP
 TMP=/tmp/tmp.paths.$$
 TOCLEAN="$TOCLEAN $TMP"
-grep '^+++\|^---' $PATCH_FILE | cut -c '5-' | grep -v /dev/null | sort | uniq > $TMP
 
-# Assume p0 to start
-PLEVEL=0
+if $PATCH -p0 -E --dry-run < $PATCH_FILE 2>&1 > $TMP; then
+  PLEVEL=0
+  #if the patch applied at P0 there is the possability that all we are doing
+  # is adding new files and they would apply anywhere. So try to guess the
+  # correct place to put those files.
 
-# if all of the lines start with a/ or b/, then this is a git patch that
-# was generated without --no-prefix
-if ! grep -qv '^a/\|^b/' $TMP ; then
-  echo Looks like this is a git patch. Stripping a/ and b/ prefixes
-  echo and incrementing PLEVEL
-  PLEVEL=$[$PLEVEL + 1]
-  sed -i -e 's,^[ab]/,,' $TMP
-fi
+  TMP2=/tmp/tmp.paths.2.$$
+  TOCLEAN="$TOCLEAN $TMP2"
 
-PREFIX_DIRS=$(cut -d '/' -f 1 $TMP | sort | uniq)
+  grep '^patching file ' $TMP | awk '{print $3}' | grep -v /dev/null | sort | uniq > $TMP2
 
-# if we are at the project root then nothing more to do
-if [[ -d hadoop-common-project ]]; then
-  echo Looks like this is being run at project root
+  #first off check that all of the files do not exist
+  FOUND_ANY=0
+  for CHECK_FILE in $(cat $TMP2)
+  do
+    if [[ -f $CHECK_FILE ]]; then
+      FOUND_ANY=1
+    fi
+  done
 
-# if all of the lines start with hadoop-common/, hadoop-hdfs/, or hadoop-mapreduce/, this is
-# relative to the hadoop root instead of the subproject root, so we need
-# to chop off another layer
-elif [[ "$PREFIX_DIRS" =~ ^(hadoop-common-project|hadoop-hdfs-project|hadoop-mapreduce-project)$ ]]; then
+  if [[ "$FOUND_ANY" = "0" ]]; then
+    #all of the files are new files so we have to guess where the correct place to put it is.
 
-  echo Looks like this is relative to project root. Increasing PLEVEL
-  PLEVEL=$[$PLEVEL + 1]
+    # if all of the lines start with a/ or b/, then this is a git patch that
+    # was generated without --no-prefix
+    if ! grep -qv '^a/\|^b/' $TMP2 ; then
+      echo Looks like this is a git patch. Stripping a/ and b/ prefixes
+      echo and incrementing PLEVEL
+      PLEVEL=$[$PLEVEL + 1]
+      sed -i -e 's,^[ab]/,,' $TMP2
+    fi
 
-elif ! echo "$PREFIX_DIRS" | grep -vxq 'hadoop-common-project\|hadoop-hdfs-project\|hadoop-mapreduce-project' ; then
-  echo Looks like this is a cross-subproject patch. Try applying from the project root
-  exit 1
+    PREFIX_DIRS_AND_FILES=$(cut -d '/' -f 1 | sort | uniq)
+
+    # if we are at the project root then nothing more to do
+    if [[ -d hadoop-common-project ]]; then
+      echo Looks like this is being run at project root
+
+    # if all of the lines start with hadoop-common/, hadoop-hdfs/, or hadoop-mapreduce/, this is
+    # relative to the hadoop root instead of the subproject root, so we need
+    # to chop off another layer
+    elif [[ "$PREFIX_DIRS_AND_FILES" =~ ^(hadoop-common-project|hadoop-hdfs-project|hadoop-mapreduce-project)$ ]]; then
+
+      echo Looks like this is relative to project root. Increasing PLEVEL
+      PLEVEL=$[$PLEVEL + 1]
+
+    elif ! echo "$PREFIX_DIRS_AND_FILES" | grep -vxq 'hadoop-common-project\|hadoop-hdfs-project\|hadoop-mapreduce-project' ; then
+      echo Looks like this is a cross-subproject patch. Try applying from the project root
+      cleanup 1
+    fi
+  fi
+elif $PATCH -p1 -E --dry-run < $PATCH_FILE 2>&1 > /dev/null; then
+  PLEVEL=1
+elif $PATCH -p2 -E --dry-run < $PATCH_FILE 2>&1 > /dev/null; then
+  PLEVEL=2
+else
+  echo "The patch does not appear to apply with p0 to p2";
+  cleanup 1;
 fi
 
 echo Going to apply patch with: $PATCH -p$PLEVEL
 $PATCH -p$PLEVEL -E < $PATCH_FILE
 
-cleanup 0
+cleanup $?
diff --git a/hadoop-common-project/hadoop-common/CHANGES.txt b/hadoop-common-project/hadoop-common/CHANGES.txt
index dd148f6b83..11523b3bfa 100644
--- a/hadoop-common-project/hadoop-common/CHANGES.txt
+++ b/hadoop-common-project/hadoop-common/CHANGES.txt
@@ -566,6 +566,9 @@ Release 0.23.0 - Unreleased
     HADOOP-7593. Fix AssertionError in TestHttpServer.testMaxThreads().
     (Uma Maheswara Rao G via szetszwo)
 
+    HADOOP-7598. Fix smart-apply-patch.sh to handle patching from a sub
+    directory correctly. (Robert Evans via acmurthy) 
+
 Release 0.22.0 - Unreleased
 
   INCOMPATIBLE CHANGES