diff --git a/core/src/main/java/hudson/model/Cause.java b/core/src/main/java/hudson/model/Cause.java
index e07b4107c70bd856577cc297d41c318df8a6a57f..e1523db771f3e1ae3b82e28c4dd8c109029deec8 100644
--- a/core/src/main/java/hudson/model/Cause.java
+++ b/core/src/main/java/hudson/model/Cause.java
@@ -177,6 +177,26 @@ public abstract class Cause {
             this.upstreamCauses = upstreamCauses;
         }
 
+        @Override
+        public void onLoad(@Nonnull Run run) {
+            Item i = Jenkins.getInstance().getItemByFullName(this.upstreamProject);
+            if (i == null || !(i instanceof Job)) {
+                // cannot initialize upstream causes
+                return;
+            }
+
+            Job j = (Job)i;
+            Run r = j.getBuildByNumber(this.getUpstreamBuild());
+            if (r == null) {
+                // build doesn't exist anymore
+                return;
+            }
+
+            for (Cause c : this.upstreamCauses) {
+                c.onLoad(r);
+            }
+        }
+
         /**
          * @since 1.515
          */
diff --git a/core/src/main/java/hudson/triggers/SCMTrigger.java b/core/src/main/java/hudson/triggers/SCMTrigger.java
index 3836b4735d7eb6f399fc3c0b71992b2a36a9bb1d..63210a206341a4dc89984708a12325754edb874b 100644
--- a/core/src/main/java/hudson/triggers/SCMTrigger.java
+++ b/core/src/main/java/hudson/triggers/SCMTrigger.java
@@ -44,6 +44,13 @@ import hudson.util.NamingThreadFactory;
 import hudson.util.SequentialExecutionQueue;
 import hudson.util.StreamTaskListener;
 import hudson.util.TimeUnit2;
+import org.apache.commons.io.FileUtils;
+import org.apache.commons.jelly.XMLOutput;
+import org.kohsuke.accmod.Restricted;
+import org.kohsuke.accmod.restrictions.DoNotUse;
+import org.kohsuke.stapler.StaplerRequest;
+import org.kohsuke.stapler.DataBoundConstructor;
+
 import java.io.File;
 import java.io.IOException;
 import java.io.PrintStream;
@@ -66,15 +73,15 @@ import jenkins.model.Jenkins;
 import jenkins.model.RunAction2;
 import jenkins.triggers.SCMTriggerItem;
 import net.sf.json.JSONObject;
-import org.apache.commons.io.FileUtils;
-import org.apache.commons.jelly.XMLOutput;
-import org.kohsuke.accmod.Restricted;
 import org.kohsuke.accmod.restrictions.NoExternalUse;
-import org.kohsuke.stapler.DataBoundConstructor;
 import org.kohsuke.stapler.QueryParameter;
-import org.kohsuke.stapler.StaplerRequest;
 import org.kohsuke.stapler.StaplerResponse;
 
+import static java.util.logging.Level.*;
+import jenkins.model.RunAction2;
+
+import javax.annotation.Nonnull;
+
 /**
  * {@link Trigger} that checks for SCM updates periodically.
  *
@@ -584,6 +591,8 @@ public class SCMTrigger extends Trigger<Item> {
          */
         private String pollingLog;
 
+        private transient Run run;
+
         public SCMTriggerCause(File logFile) throws IOException {
             // TODO: charset of this log file?
             this(FileUtils.readFileToString(logFile));
@@ -601,8 +610,14 @@ public class SCMTrigger extends Trigger<Item> {
             this("");
         }
 
+        @Override
+        public void onLoad(Run run) {
+            this.run = run;
+        }
+
         @Override
         public void onAddedTo(Run build) {
+            this.run = build;
             try {
                 BuildAction a = new BuildAction(build);
                 FileUtils.writeStringToFile(a.getPollingLogFile(),pollingLog);
@@ -618,6 +633,11 @@ public class SCMTrigger extends Trigger<Item> {
             return Messages.SCMTrigger_SCMTriggerCause_ShortDescription();
         }
 
+        @Restricted(DoNotUse.class)
+        public Run getRun() {
+            return this.run;
+        }
+
         @Override
         public boolean equals(Object o) {
             return o instanceof SCMTriggerCause;
diff --git a/core/src/main/resources/hudson/triggers/SCMTrigger/SCMTriggerCause/description.jelly b/core/src/main/resources/hudson/triggers/SCMTrigger/SCMTriggerCause/description.jelly
index f8a53717a679c10291b3155047bc461c58efcc31..c377b51e16d7328918916fb15a9fb748655f6db0 100644
--- a/core/src/main/resources/hudson/triggers/SCMTrigger/SCMTriggerCause/description.jelly
+++ b/core/src/main/resources/hudson/triggers/SCMTrigger/SCMTriggerCause/description.jelly
@@ -23,5 +23,6 @@ THE SOFTWARE.
 -->
 <?jelly escape-by-default='true'?>
 <j:jelly xmlns:j="jelly:core" xmlns:st="jelly:stapler" xmlns:d="jelly:define" xmlns:l="/lib/layout" xmlns:t="/lib/hudson" xmlns:f="/lib/form">
-    <span><a href="pollingLog">${it.shortDescription}</a></span>
+    <!-- this link loses breadcrumb context, but need absolute URL for upstream cause support (JENKINS-18048) -->
+    <span><a href="${rootURL}/${it.run.url}pollingLog">${it.shortDescription}</a></span>
 </j:jelly>