diff --git a/embassy-stm32/src/dma/ringbuffer.rs b/embassy-stm32/src/dma/ringbuffer.rs
index c5b42060a..23f1d67d5 100644
--- a/embassy-stm32/src/dma/ringbuffer.rs
+++ b/embassy-stm32/src/dma/ringbuffer.rs
@@ -37,6 +37,7 @@ pub struct ReadableDmaRingBuffer<'a, W: Word> {
 }
 
 #[derive(Debug, PartialEq)]
+#[cfg_attr(feature = "defmt", derive(defmt::Format))]
 pub struct OverrunError;
 
 pub trait DmaCtrl {