diff --git a/src/lib.rs b/src/lib.rs
index e76390332..3ef775c19 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -64,7 +64,6 @@ fn bspatch_rs(py: Python<'_>, source: i32, patch: &[u8]) -> io::Result<Vec<u8>>
             file.set_len(target.len() as u64)?;
             std::mem::forget(file);
         }
-        mmap.flush_async()?;
         Ok(target)
     })
 }