diff --git a/crates/rng/src/vhu_rng.rs b/crates/rng/src/vhu_rng.rs
index d51755e..66ba24e 100644
--- a/crates/rng/src/vhu_rng.rs
+++ b/crates/rng/src/vhu_rng.rs
@@ -124,7 +124,7 @@ impl<T: Read> VuRngBackend<T> {
 
             let descriptor = descriptors[0];
             let mut to_read = descriptor.len() as usize;
-            let mut timer = &mut self.timer;
+            let timer = &mut self.timer;
 
             if !descriptor.is_write_only() {
                 return Err(VuRngError::UnexpectedReadDescriptor);