1 files changed, 4 insertions, 0 deletions
diff --git a/activerecord/lib/active_record/associations/preloader/association.rb b/activerecord/lib/active_record/associations/preloader/association.rb
index 441768f302..c0639742be 100644
--- a/activerecord/lib/active_record/associations/preloader/association.rb
+++ b/activerecord/lib/active_record/associations/preloader/association.rb
@@ -151,6 +151,10 @@ module ActiveRecord
             end
           end
 
+          if preload_values[:readonly] || values[:readonly]
+            scope.readonly!
+          end
+
           if options[:as]
             scope.where!(klass.table_name => { reflection.type => model.base_class.sti_name })
           end