code: func (container *Container) UnmountIpcMount() error {
  	if container.HasMountFor("/dev/shm") {
  		return nil
  	}
  
  	// container.ShmPath should not be used here as it may point
  	// to the host's or other container's /dev/shm
  	shmPath, err := container.ShmResourcePath()
  	if err != nil {
  		return err
  	}
  	if shmPath == "" {
  		return nil
  	}
  	if err = mount.Unmount(shmPath); err != nil && !os.IsNotExist(err) {
  		return err
  	}
  	return nil
  }
docs: // UnmountIpcMount unmounts shm if it was mounted