include/linux/err.h:71: warning: No description found for return value of 'IS_ERR_OR_NULL'
include/linux/err.h:83: warning: No description found for return value of 'ERR_CAST'
include/linux/err.h:80: warning: No description found for return value of 'IS_ERR_OR_NULL'
include/linux/err.h:92: warning: No description found for return value of 'ERR_CAST'