ignore the loopbackdevice error, or the rbd volume will not get detached

pkg/volume/rbd/rbd.go

@@ -940,14 +940,20 @@ func (rbd *rbdDiskUnmapper) TearDownDevice(mapPath, _ string) error {
 	blkUtil := volumepathhandler.NewBlockVolumePathHandler()
 	loop, err := volumepathhandler.BlockVolumePathHandler.GetLoopDevice(blkUtil, device)
 	if err != nil {
-		return fmt.Errorf("rbd: failed to get loopback for device: %v, err: %v", device, err)
-	}
-	// Remove loop device before detaching volume since volume detach operation gets busy if volume is opened by loopback.
-	err = volumepathhandler.BlockVolumePathHandler.RemoveLoopDevice(blkUtil, loop)
-	if err != nil {
-		return fmt.Errorf("rbd: failed to remove loopback :%v, err: %v", loop, err)
+		if err.Error() != volumepathhandler.ErrDeviceNotFound {
+			return fmt.Errorf("rbd: failed to get loopback for device: %v, err: %v", device, err)
+		}
+		glog.Warning("rbd: loopback for device: % not found", device)
+	} else {
+		if len(loop) != 0 {
+			// Remove loop device before detaching volume since volume detach operation gets busy if volume is opened by loopback.
+			err = volumepathhandler.BlockVolumePathHandler.RemoveLoopDevice(blkUtil, loop)
+			if err != nil {
+				return fmt.Errorf("rbd: failed to remove loopback :%v, err: %v", loop, err)
+			}
+			glog.V(4).Infof("rbd: successfully removed loop device: %s", loop)
+		}
 	}
-	glog.V(4).Infof("rbd: successfully removed loop device: %s", loop)
 
 	err = rbd.manager.DetachBlockDisk(*rbd, mapPath)
 	if err != nil {

pkg/volume/util/operationexecutor/operation_generator.go

@@ -1058,11 +1058,18 @@ func (og *operationGenerator) GenerateUnmapDeviceFunc(
 		glog.V(4).Infof("UnmapDevice: deviceToDetach.DevicePath: %v", deviceToDetach.DevicePath)
 		loopPath, err := og.blkUtil.GetLoopDevice(deviceToDetach.DevicePath)
 		if err != nil {
-			glog.Warningf(deviceToDetach.GenerateMsgDetailed("UnmapDevice: Couldn't find loopback device which takes file descriptor lock", fmt.Sprintf("device path: %q", deviceToDetach.DevicePath)))
+			if err.Error() == volumepathhandler.ErrDeviceNotFound {
+				glog.Warningf(deviceToDetach.GenerateMsgDetailed("UnmapDevice: Couldn't find loopback device which takes file descriptor lock", fmt.Sprintf("device path: %q", deviceToDetach.DevicePath)))
+			} else {
+				errInfo := "UnmapDevice.GetLoopDevice failed to get loopback device, " + fmt.Sprintf("device path: %q", deviceToDetach.DevicePath)
+				return deviceToDetach.GenerateError(errInfo, err)
+			}
 		} else {
-			err = og.blkUtil.RemoveLoopDevice(loopPath)
-			if err != nil {
-				return deviceToDetach.GenerateError("UnmapDevice.AttachFileDevice failed", err)
+			if len(loopPath) != 0 {
+				err = og.blkUtil.RemoveLoopDevice(loopPath)
+				if err != nil {
+					return deviceToDetach.GenerateError("UnmapDevice.RemoveLoopDevice failed", err)
+				}
 			}
 		}