diff --git a/rust/kernel/block/mq/request.rs b/rust/kernel/block/mq/request.rs
index ce3e30c81cb5..75d3fdf896e0 100644
--- a/rust/kernel/block/mq/request.rs
+++ b/rust/kernel/block/mq/request.rs
@@ -39,7 +39,7 @@ use core::{marker::PhantomData, ptr::NonNull};
 /// back ownership to the block layer.
 ///
 /// Note that the driver can still obtain new `ARef` even if there is no `ARef`s in existence by
-/// using `tag_to_rq`, hence the need to distinguish B and C.
+/// using `tag_to_rq`, hence the need to distinguish 2 and 3.
 ///
 /// The states are tracked through the private `refcount` field of
 /// `RequestDataWrapper`. This structure lives in the private data area of the C