diff --git a/doc/source/guides/neutron.rst b/doc/source/guides/neutron.rst
index 3030c7b..b0a8907 100644
--- a/doc/source/guides/neutron.rst
+++ b/doc/source/guides/neutron.rst
@@ -131,6 +131,11 @@
 subnet that exists in the private RFC1918 address space - however in
 in a real setup FLOATING_RANGE would be a public IP address range.
 
+Note that extension drivers for the ML2 plugin is set by
+`Q_ML2_PLUGIN_EXT_DRIVERS`, and it includes 'port_security' by default. If you
+want to remove all the extension drivers (even 'port_security'), set
+`Q_ML2_PLUGIN_EXT_DRIVERS` to blank.
+
 Neutron Networking with Open vSwitch and Provider Networks
 ==========================================================
 
diff --git a/lib/neutron_plugins/ml2 b/lib/neutron_plugins/ml2
index 8853777..2733f1f 100644
--- a/lib/neutron_plugins/ml2
+++ b/lib/neutron_plugins/ml2
@@ -31,6 +31,9 @@
 Q_ML2_PLUGIN_VXLAN_TYPE_OPTIONS=${Q_ML2_PLUGIN_VXLAN_TYPE_OPTIONS:-vni_ranges=1001:2000}
 # Default VLAN TypeDriver options
 Q_ML2_PLUGIN_VLAN_TYPE_OPTIONS=${Q_ML2_PLUGIN_VLAN_TYPE_OPTIONS:-}
+# List of extension drivers to load, use '-' instead of ':-' to allow people to
+# explicitly override this to blank
+Q_ML2_PLUGIN_EXT_DRIVERS=${Q_ML2_PLUGIN_EXT_DRIVERS-port_security}
 
 # L3 Plugin to load for ML2
 ML2_L3_PLUGIN=${ML2_L3_PLUGIN:-neutron.services.l3_router.l3_router_plugin.L3RouterPlugin}
@@ -113,6 +116,8 @@
 
     populate_ml2_config /$Q_PLUGIN_CONF_FILE ml2 type_drivers=$Q_ML2_PLUGIN_TYPE_DRIVERS
 
+    populate_ml2_config /$Q_PLUGIN_CONF_FILE ml2 extension_drivers=$Q_ML2_PLUGIN_EXT_DRIVERS
+
     populate_ml2_config /$Q_PLUGIN_CONF_FILE ml2 $Q_SRV_EXTRA_OPTS
 
     populate_ml2_config /$Q_PLUGIN_CONF_FILE ml2_type_gre $Q_ML2_PLUGIN_GRE_TYPE_OPTIONS