code: func verifyDevicePath(devicePaths []string, sdBeforeSet sets.String, diskName string) (string, error) {
  	if err := udevadmChangeToNewDrives(sdBeforeSet); err != nil {
  		// It's possible udevadm was called on other disks so it should not block this
  		// call. If it did fail on this disk, then the devicePath will either
  		// not exist or be wrong. If it's wrong, then the scsi_id check below will fail.
  		klog.Errorf("udevadmChangeToNewDrives failed with: %v", err)
  	}
  
  	for _, path := range devicePaths {
  		if pathExists, err := mount.PathExists(path); err != nil {
  			return "", fmt.Errorf("Error checking if path exists: %v", err)
  		} else if pathExists {
  			// validate that the path actually resolves to the correct disk
  			serial, err := getScsiSerial(path, diskName)
  			if err != nil {
  				return "", fmt.Errorf("failed to get scsi serial %v", err)
  			}
  			if serial != diskName {
  				// The device link is not pointing to the correct device
  				// Trigger udev on this device to try to fix the link
  				if udevErr := udevadmChangeToDrive(path); udevErr != nil {
  					klog.Errorf("udevadmChangeToDrive %q failed with: %v", path, err)
  				}
  
  				// Return error to retry WaitForAttach and verifyDevicePath
  				return "", fmt.Errorf("scsi_id serial %q for device %q doesn't match disk %q", serial, path, diskName)
  			}
  			// The device link is correct
  			return path, nil
  		}
  	}
  
  	return "", nil
  }
docs: // Returns the first path that exists, or empty string if none exist.