diff --git a/LICENSE b/LICENSE
index b771bd552b762..3514a1eb2d672 100644
--- a/LICENSE
+++ b/LICENSE
@@ -258,4 +258,4 @@ data/mllib/images/kittens/29.5.a_b_EGDP022204.jpg
 data/mllib/images/kittens/54893.jpg
 data/mllib/images/kittens/DP153539.jpg
 data/mllib/images/kittens/DP802813.jpg
-data/mllib/images/multi-channel/chr30.4.184.jpg
\ No newline at end of file
+data/mllib/images/multi-channel/chr30.4.184.jpg
diff --git a/dev/deps/spark-deps-hadoop-2.6 b/dev/deps/spark-deps-hadoop-2.6
index aca5bbbe02eb6..1d45d3750ec97 100644
--- a/dev/deps/spark-deps-hadoop-2.6
+++ b/dev/deps/spark-deps-hadoop-2.6
@@ -118,7 +118,7 @@ jersey-media-jaxb-2.22.2.jar
 jersey-server-2.22.2.jar
 jetty-6.1.26.jar
 jetty-util-6.1.26.jar
-jline-2.14.6.jar
+jline-2.12.1.jar
 joda-time-2.9.3.jar
 jodd-core-3.5.2.jar
 jpam-1.1.jar
@@ -169,10 +169,10 @@ parquet-jackson-1.10.0.jar
 protobuf-java-2.5.0.jar
 py4j-0.10.7.jar
 pyrolite-4.13.jar
-scala-compiler-2.11.12.jar
-scala-library-2.11.12.jar
-scala-parser-combinators_2.11-1.1.0.jar
-scala-reflect-2.11.12.jar
+scala-compiler-2.11.8.jar
+scala-library-2.11.8.jar
+scala-parser-combinators_2.11-1.0.4.jar
+scala-reflect-2.11.8.jar
 scala-xml_2.11-1.0.5.jar
 shapeless_2.11-2.3.2.jar
 slf4j-api-1.7.16.jar
diff --git a/dev/deps/spark-deps-hadoop-2.7 b/dev/deps/spark-deps-hadoop-2.7
index 0902af1dfdc65..1cc3c51b3e3f6 100644
--- a/dev/deps/spark-deps-hadoop-2.7
+++ b/dev/deps/spark-deps-hadoop-2.7
@@ -119,7 +119,7 @@ jersey-server-2.22.2.jar
 jetty-6.1.26.jar
 jetty-sslengine-6.1.26.jar
 jetty-util-6.1.26.jar
-jline-2.14.6.jar
+jline-2.12.1.jar
 joda-time-2.9.3.jar
 jodd-core-3.5.2.jar
 jpam-1.1.jar
@@ -171,10 +171,10 @@ parquet-jackson-1.10.0.jar
 protobuf-java-2.5.0.jar
 py4j-0.10.7.jar
 pyrolite-4.13.jar
-scala-compiler-2.11.12.jar
-scala-library-2.11.12.jar
-scala-parser-combinators_2.11-1.1.0.jar
-scala-reflect-2.11.12.jar
+scala-compiler-2.11.8.jar
+scala-library-2.11.8.jar
+scala-parser-combinators_2.11-1.0.4.jar
+scala-reflect-2.11.8.jar
 scala-xml_2.11-1.0.5.jar
 shapeless_2.11-2.3.2.jar
 slf4j-api-1.7.16.jar
diff --git a/dev/deps/spark-deps-hadoop-3.1 b/dev/deps/spark-deps-hadoop-3.1
index 35cf1cd85fd80..599b3a972bf42 100644
--- a/dev/deps/spark-deps-hadoop-3.1
+++ b/dev/deps/spark-deps-hadoop-3.1
@@ -118,7 +118,7 @@ jersey-media-jaxb-2.22.2.jar
 jersey-server-2.22.2.jar
 jetty-webapp-9.3.24.v20180605.jar
 jetty-xml-9.3.24.v20180605.jar
-jline-2.14.6.jar
+jline-2.12.1.jar
 joda-time-2.9.3.jar
 jodd-core-3.5.2.jar
 jpam-1.1.jar
@@ -189,10 +189,10 @@ protobuf-java-2.5.0.jar
 py4j-0.10.7.jar
 pyrolite-4.13.jar
 re2j-1.1.jar
-scala-compiler-2.11.12.jar
-scala-library-2.11.12.jar
-scala-parser-combinators_2.11-1.1.0.jar
-scala-reflect-2.11.12.jar
+scala-compiler-2.11.8.jar
+scala-library-2.11.8.jar
+scala-parser-combinators_2.11-1.0.4.jar
+scala-reflect-2.11.8.jar
 scala-xml_2.11-1.0.5.jar
 shapeless_2.11-2.3.2.jar
 slf4j-api-1.7.16.jar
diff --git a/pom.xml b/pom.xml
index a4184c3153336..5eecd037993f4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -155,7 +155,7 @@
     <commons.math3.version>3.4.1</commons.math3.version>
     <!-- managed up from 3.2.1 for SPARK-11652 -->
     <commons.collections.version>3.2.2</commons.collections.version>
-    <scala.version>2.11.12</scala.version>
+    <scala.version>2.11.8</scala.version>
     <scala.binary.version>2.11</scala.binary.version>
     <codehaus.jackson.version>1.9.13</codehaus.jackson.version>
     <fasterxml.jackson.version>2.6.7</fasterxml.jackson.version>
@@ -740,13 +740,13 @@
       <dependency>
         <groupId>org.scala-lang.modules</groupId>
         <artifactId>scala-parser-combinators_${scala.binary.version}</artifactId>
-        <version>1.1.0</version>
+        <version>1.0.4</version>
       </dependency>
       <!-- SPARK-16770 affecting Scala 2.11.x -->
       <dependency>
         <groupId>jline</groupId>
         <artifactId>jline</artifactId>
-        <version>2.14.6</version>
+        <version>2.12.1</version>
       </dependency>
       <dependency>
         <groupId>org.scalatest</groupId>
@@ -2756,7 +2756,7 @@
     <profile>
       <id>scala-2.12</id>
       <properties>
-        <scala.version>2.12.6</scala.version>
+        <scala.version>2.12.4</scala.version>
         <scala.binary.version>2.12</scala.binary.version>
       </properties>
       <build>
diff --git a/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoop.scala b/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoop.scala
index a44051b351e19..e69441a475e9a 100644
--- a/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoop.scala
+++ b/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoop.scala
@@ -36,7 +36,7 @@ class SparkILoop(in0: Option[BufferedReader], out: JPrintWriter)
   def this() = this(None, new JPrintWriter(Console.out, true))
 
   override def createInterpreter(): Unit = {
-    intp = new SparkILoopInterpreter(settings, out, initializeSpark)
+    intp = new SparkILoopInterpreter(settings, out)
   }
 
   val initializationCommands: Seq[String] = Seq(
@@ -73,15 +73,11 @@ class SparkILoop(in0: Option[BufferedReader], out: JPrintWriter)
     "import org.apache.spark.sql.functions._"
   )
 
-  def initializeSpark(): Unit = {
-    if (!intp.reporter.hasErrors) {
-      // `savingReplayStack` removes the commands from session history.
-      savingReplayStack {
-        initializationCommands.foreach(intp quietRun _)
+  def initializeSpark() {
+    intp.beQuietDuring {
+      savingReplayStack { // remove the commands from session history.
+        initializationCommands.foreach(processLine)
       }
-    } else {
-      throw new RuntimeException(s"Scala $versionString interpreter encountered " +
-        "errors during initialization")
     }
   }
 
@@ -105,6 +101,16 @@ class SparkILoop(in0: Option[BufferedReader], out: JPrintWriter)
   /** Available commands */
   override def commands: List[LoopCommand] = standardCommands
 
+  /**
+   * We override `loadFiles` because we need to initialize Spark *before* the REPL
+   * sees any files, so that the Spark context is visible in those files. This is a bit of a
+   * hack, but there isn't another hook available to us at this point.
+   */
+  override def loadFiles(settings: Settings): Unit = {
+    initializeSpark()
+    super.loadFiles(settings)
+  }
+
   override def resetCommand(line: String): Unit = {
     super.resetCommand(line)
     initializeSpark()
diff --git a/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoopInterpreter.scala b/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoopInterpreter.scala
index 4e63816402a10..e736607a9a6b9 100644
--- a/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoopInterpreter.scala
+++ b/repl/scala-2.11/src/main/scala/org/apache/spark/repl/SparkILoopInterpreter.scala
@@ -21,22 +21,8 @@ import scala.collection.mutable
 import scala.tools.nsc.Settings
 import scala.tools.nsc.interpreter._
 
-class SparkILoopInterpreter(settings: Settings, out: JPrintWriter, initializeSpark: () => Unit)
-    extends IMain(settings, out) { self =>
-
-  /**
-   * We override `initializeSynchronous` to initialize Spark *after* `intp` is properly initialized
-   * and *before* the REPL sees any files in the private `loadInitFiles` functions, so that
-   * the Spark context is visible in those files.
-   *
-   * This is a bit of a hack, but there isn't another hook available to us at this point.
-   *
-   * See the discussion in Scala community https://github.com/scala/bug/issues/10913 for detail.
-   */
-  override def initializeSynchronous(): Unit = {
-    super.initializeSynchronous()
-    initializeSpark()
-  }
+class SparkILoopInterpreter(settings: Settings, out: JPrintWriter) extends IMain(settings, out) {
+  self =>
 
   override lazy val memberHandlers = new {
     val intp: self.type = self