code: func isSysFSWritable() (bool, error) {
  	const permWritable = "rw"
  	const sysfsDevice = "sysfs"
  	m := mount.New("" /* default mount path */)
  	mountPoints, err := m.List()
  	if err != nil {
  		klog.Errorf("failed to list mount points: %v", err)
  		return false, err
  	}
  
  	for _, mountPoint := range mountPoints {
  		if mountPoint.Type != sysfsDevice {
  			continue
  		}
  		// Check whether sysfs is 'rw'
  		if len(mountPoint.Opts) > 0 && mountPoint.Opts[0] == permWritable {
  			return true, nil
  		}
  		klog.Errorf("sysfs is not writable: %+v (mount options are %v)",
  			mountPoint, mountPoint.Opts)
  		return false, errReadOnlySysFS
  	}
  
  	return false, errors.New("no sysfs mounted")
  }
docs: // isSysFSWritable checks /proc/mounts to see whether sysfs is 'rw' or not.