When you get this error:
Missing argument 2 for wp_kses
How to fix error missing argument 2 for wp_kses
Change this line
update_post_meta( $post_id, 'post_meta', wp_kses( $_POST['post_meta']) );
to this line:
update_post_meta( $post_id, 'post_meta', wp_kses_post( $_POST['post_meta']) );