diff --git a/tools/examples/block b/tools/examples/block
index 411e6813fe..2f3a645d7a 100644
--- a/tools/examples/block
+++ b/tools/examples/block
@@ -326,7 +326,10 @@ mount it read-write in a guest domain."
           fatal 'Failed to find an unused loop device'
         fi
 
-        do_or_die losetup "$loopdev" "$file"
+        status=$(losetup "$loopdev" "$file" || echo "failed")
+        if [ -n "$status" ]; then
+          do_or_die losetup -r "$loopdev" "$file"
+        fi
         xenstore_write "$XENBUS_PATH/node" "$loopdev"
         write_dev "$loopdev"
         release_lock "block"