diff --git a/plugins/modules/mysql_user.py b/plugins/modules/mysql_user.py
index 8d6c36a..2cdc6a4 100644
--- a/plugins/modules/mysql_user.py
+++ b/plugins/modules/mysql_user.py
@@ -527,7 +527,7 @@ def user_mod(cursor, user, host, host_all, password, encrypted,
     old_user_mgmt = use_old_user_mgmt(cursor)
 
     if host_all:
-        hostnames = user_get_hostnames(cursor, [user])
+        hostnames = user_get_hostnames(cursor, user)
     else:
         hostnames = [host]