4 files changed, 11 insertions, 4 deletions
diff --git a/src/libs/client/NodeModel.cpp b/src/libs/client/NodeModel.cpp
index d1c6c271..7cee66f9 100644
--- a/src/libs/client/NodeModel.cpp
+++ b/src/libs/client/NodeModel.cpp
@@ -167,7 +167,7 @@ NodeModel::port_value_range(SharedPtr<PortModel> port, float& min, float& max)
 
 		if (!_min_values) {
 		  
-		  Glib::Mutex::Lock(PluginModel::rdf_world()->mutex());
+		  Glib::Mutex::Lock lock(PluginModel::rdf_world()->mutex());
 		  
 		  uint32_t num_lv2_ports = slv2_plugin_get_num_ports(_plugin->slv2_plugin());
 		  _min_values = new float[num_lv2_ports];
diff --git a/src/libs/client/PluginModel.cpp b/src/libs/client/PluginModel.cpp
index 8c2705da..db62b3bf 100644
--- a/src/libs/client/PluginModel.cpp
+++ b/src/libs/client/PluginModel.cpp
@@ -50,9 +50,9 @@ PluginModel::ui(Ingen::Shared::World* world, SharedPtr<NodeModel> node) const
 	if (_type != LV2)
 		return SharedPtr<PluginUI>();
 
-	Glib::Mutex::Lock(_rdf_world->mutex());
-
-	return PluginUI::create(world, node, _slv2_plugin);
+	Glib::Mutex::Lock lock(_rdf_world->mutex());
+	SharedPtr<PluginUI> ret = PluginUI::create(world, node, _slv2_plugin);
+	return ret;
 }
 
 
@@ -69,6 +69,8 @@ PluginModel::icon_path() const
 string
 PluginModel::get_lv2_icon_path(SLV2Plugin plugin)
 {
+	Glib::Mutex::Lock lock(_rdf_world->mutex());
+
 	string result;
 	SLV2Value svg_icon_pred = slv2_value_new_uri(_slv2_world,
 		"http://ll-plugins.nongnu.org/lv2/namespace#svgIcon");
diff --git a/src/libs/client/PluginModel.hpp b/src/libs/client/PluginModel.hpp
index 4e2bfab1..a7adc735 100644
--- a/src/libs/client/PluginModel.hpp
+++ b/src/libs/client/PluginModel.hpp
@@ -55,6 +55,7 @@ public:
 		, _name(name)
 	{
 #ifdef HAVE_SLV2
+		Glib::Mutex::Lock lock(_rdf_world->mutex());
 		SLV2Value plugin_uri = slv2_value_new_uri(_slv2_world, uri.c_str());
 		_slv2_plugin = slv2_plugins_get_by_uri(_slv2_plugins, plugin_uri);
 		slv2_value_free(plugin_uri);
@@ -89,10 +90,12 @@ public:
 	SLV2Plugin       slv2_plugin() { return _slv2_plugin; }
 
 	SLV2Port slv2_port(uint32_t index) {
+		Glib::Mutex::Lock lock(_rdf_world->mutex());
 		return slv2_plugin_get_port_by_index(_slv2_plugin, index);
 	}
 
 	static void set_slv2_world(SLV2World world) {
+		Glib::Mutex::Lock lock(_rdf_world->mutex());
 		_slv2_world = world; 
 		_slv2_plugins = slv2_world_get_all_plugins(_slv2_world);
 	}
diff --git a/src/libs/client/PluginUI.cpp b/src/libs/client/PluginUI.cpp
index b341bb0f..f2f591bd 100644
--- a/src/libs/client/PluginUI.cpp
+++ b/src/libs/client/PluginUI.cpp
@@ -107,6 +107,7 @@ PluginUI::PluginUI(Ingen::Shared::World* world,
 
 PluginUI::~PluginUI()
 {
+	Glib::Mutex::Lock lock(PluginModel::rdf_world()->mutex());
 	slv2_ui_instance_free(_instance);
 }
 
@@ -116,6 +117,7 @@ PluginUI::create(Ingen::Shared::World* world,
                  SharedPtr<NodeModel>  node,
                  SLV2Plugin            plugin)
 {
+	Glib::Mutex::Lock lock(PluginModel::rdf_world()->mutex());
 	SharedPtr<PluginUI> ret;
 
 	SLV2Value gtk_gui_uri = slv2_value_new_uri(world->slv2_world,