diff -Nru update-notifier-3.160/data/update-motd-updates-available update-notifier-3.160ubuntu1/data/update-motd-updates-available
--- update-notifier-3.160/data/update-motd-updates-available	2015-01-20 10:33:30.000000000 +0100
+++ update-notifier-3.160ubuntu1/data/update-motd-updates-available	2015-10-06 15:55:50.000000000 +0200
@@ -23,25 +23,37 @@
 eval "$(apt-config shell EtcDir Dir::Etc)"
 eval "$(apt-config shell SourceList Dir::Etc::sourcelist)"
 
-# check if we have a list file or sources.list that needs checking
-if [ -e "$stamp" ]; then
-    if [ "$(find "/$StateDir/$ListDir" "/$EtcDir/$SourceList" -type f -newer "$stamp" -print -quit)" ]; then
-        NEED_UPDATE_CHECK=yes
-    fi
-else
-    if [ "$(find "/$StateDir/$ListDir" "/$EtcDir/$SourceList" -type f -print -quit)" ]; then
-        NEED_UPDATE_CHECK=yes
-    fi
+# avoiding stalls on login
+# output what we have cached and asynchronously generate an update
+if [ -f "$stamp" ]; then
+        cat "$stamp"
 fi
 
-# output something for update-motd
-if [ -n "$NEED_UPDATE_CHECK" ]; then
-    {
-        echo ""
-        /usr/lib/update-notifier/apt-check --human-readable
-        echo ""
-    } > $stamp
-fi
+cleanup() { rm -f "$tmpfile"; }
 
-# output what we have (either cached or newly generated)
-cat "$stamp"
+(
+    # check if we have a list file or sources.list that needs checking
+    if [ -e "$stamp" ]; then
+        if [ "$(find "/$StateDir/$ListDir" "/$EtcDir/$SourceList" -type f -newer "$stamp" -print -quit)" ]; then
+            NEED_UPDATE_CHECK=yes
+        fi
+    else
+        if [ "$(find "/$StateDir/$ListDir" "/$EtcDir/$SourceList" -type f -print -quit)" ]; then
+            NEED_UPDATE_CHECK=yes
+        fi
+    fi
+    
+    trap cleanup EXIT
+    tmpfile=$(mktemp)
+
+    # output something for update-motd
+    if [ -n "$NEED_UPDATE_CHECK" ]; then
+        {
+
+            echo ""
+            /usr/lib/update-notifier/apt-check --human-readable
+            echo ""
+        } > "$tmpfile"
+        mv "$tmpfile" "$stamp"
+    fi
+) &
diff -Nru update-notifier-3.160/debian/changelog update-notifier-3.160ubuntu1/debian/changelog
--- update-notifier-3.160/debian/changelog	2015-01-20 10:34:47.000000000 +0100
+++ update-notifier-3.160ubuntu1/debian/changelog	2015-10-06 16:11:20.000000000 +0200
@@ -1,3 +1,10 @@
+update-notifier (3.160ubuntu1) vivid; urgency=medium
+
+  * data/update-motd-updates-available: avoid login stalls due to motd updates
+    executing the slow part of the update asynchronously (LP: #525674)
+
+ -- Christian Ehrhardt <christian.ehrhardt@canonical.com>  Tue, 06 Oct 2015 16:06:55 +0200
+
 update-notifier (3.160) vivid; urgency=medium
 
   * ./debian/update-notifier-cds.conf: Stop asking udisks 1 for the