diff --git a/drivers/block/rnull/configfs.rs b/drivers/block/rnull/configfs.rs
index 6713a6d92391..2f5a7da03af5 100644
--- a/drivers/block/rnull/configfs.rs
+++ b/drivers/block/rnull/configfs.rs
@@ -25,7 +25,7 @@ pub(crate) fn subsystem() -> impl PinInit<kernel::configfs::Subsystem<Config>, E
         ],
     };
 
-    kernel::configfs::Subsystem::new(c_str!("rnull"), item_type, try_pin_init!(Config {}))
+    kernel::configfs::Subsystem::new(c"rnull", item_type, try_pin_init!(Config {}))
 }
 
 #[pin_data]