diff --git a/lib/vagrant-libvirt/action/handle_box_image.rb b/lib/vagrant-libvirt/action/handle_box_image.rb
index 45dacf0..b08ed17 100644
--- a/lib/vagrant-libvirt/action/handle_box_image.rb
+++ b/lib/vagrant-libvirt/action/handle_box_image.rb
@@ -37,9 +37,12 @@ module VagrantPlugins
           env[:box_volume_name] = env[:machine].box.name.to_s.dup.gsub("/", "-VAGRANTSLASH-")
           env[:box_volume_name] << "_vagrant_box_image_#{env[:machine].box.version.to_s rescue ''}.img"
 
+          # while inside the synchronize block take care not to call the next
+          # action in the chain, as must exit this block first to prevent
+          # locking all subsequent actions as well.
           @@lock.synchronize do
             # Don't continue if image already exists in storage pool.
-            return @app.call(env) if ProviderLibvirt::Util::Collection.find_matching(
+            break if ProviderLibvirt::Util::Collection.find_matching(
               env[:libvirt_compute].volumes.all, env[:box_volume_name])
 
             # Box is not available as a storage pool volume. Create and upload
diff --git a/lib/vagrant-libvirt/action/handle_storage_pool.rb b/lib/vagrant-libvirt/action/handle_storage_pool.rb
index e405638..f567687 100644
--- a/lib/vagrant-libvirt/action/handle_storage_pool.rb
+++ b/lib/vagrant-libvirt/action/handle_storage_pool.rb
@@ -14,14 +14,16 @@ module VagrantPlugins
         end
 
         def call(env)
-          @@lock.synchronize do
-            # Get config options.
-            config = env[:machine].provider_config
+          # Get config options.
+          config = env[:machine].provider_config
 
+          # while inside the synchronize block take care not to call the next
+          # action in the chain, as must exit this block first to prevent
+          # locking all subsequent actions as well.
+          @@lock.synchronize do
             # Check for storage pool, where box image should be created
-            fog_pool = ProviderLibvirt::Util::Collection.find_matching(
+            break if ProviderLibvirt::Util::Collection.find_matching(
               env[:libvirt_compute].pools.all, config.storage_pool_name)
-            return @app.call(env) if fog_pool
 
             @logger.info("No storage pool '#{config.storage_pool_name}' is available.")