diff --git a/libs/devicemapper/src/loopdevice.rs b/libs/devicemapper/src/loopdevice.rs
index b830eda..30ab6f6 100644
--- a/libs/devicemapper/src/loopdevice.rs
+++ b/libs/devicemapper/src/loopdevice.rs
@@ -199,6 +199,12 @@
         "0" == fs::read_to_string(ro).unwrap().trim()
     }
 
+    fn is_autoclear(dev: &Path) -> bool {
+        let autoclear =
+            Path::new("/sys/block").join(dev.file_name().unwrap()).join("loop/autoclear");
+        "1" == fs::read_to_string(autoclear).unwrap().trim()
+    }
+
     #[rdroidtest]
     fn attach_loop_device_with_dio() {
         let a_dir = tempfile::TempDir::new().unwrap();
@@ -258,10 +264,7 @@
         let dev =
             attach(a_file, 0, a_size, &LoopConfigOptions { autoclear: true, ..Default::default() })
                 .unwrap();
-        drop(dev.file);
 
-        let dev_size_path =
-            Path::new("/sys/block").join(dev.path.file_name().unwrap()).join("size");
-        assert_eq!("0", fs::read_to_string(dev_size_path).unwrap().trim());
+        assert!(is_autoclear(&dev.path));
     }
 }