code: func (c *containerAdapter) checkMounts() error {
  	spec := c.container.spec()
  	for _, mount := range spec.Mounts {
  		switch mount.Type {
  		case api.MountTypeBind:
  			if _, err := os.Stat(mount.Source); os.IsNotExist(err) {
  				return fmt.Errorf("invalid bind mount source, source path not found: %s", mount.Source)
  			}
  		}
  	}
  
  	return nil
  }
docs: // checkMounts ensures that the provided mounts won't have any host-specific
  // problems at start up. For example, we disallow bind mounts without an
  // existing path, which slightly different from the container API.