diff --git a/runtime/starpu/control/runtime_options.c b/runtime/starpu/control/runtime_options.c
index 32dce7c5b9c3e717a61fd702b836ad3e4721b07b..58675030a3f43323cd55afbea18b16c4047f061e 100644
--- a/runtime/starpu/control/runtime_options.c
+++ b/runtime/starpu/control/runtime_options.c
@@ -57,7 +57,7 @@ int RUNTIME_options_ws_alloc( RUNTIME_option_t *options, size_t worker_size, siz
         };
         options->ws_wsize = worker_size;
         starpu_cham_tile_register( (starpu_data_handle_t*)(&(options->ws_worker)),
-                                   -1, &tile, sizeof(char) );
+                                   -1, &tile, ChamByte );
     }
     if ( host_size > 0 ) {
         options->ws_hsize = host_size;