44. Bus Error Checker

How do you plan to solve it?

/*Write your code here*/
module error_checker_xz (
    input [7:0] bus,
    output all_known,has_unknown,
    output [7:0] bus_if_known
);
wire xz= (^bus===1'bx);
assign all_known=xz? 1'b0 : 1'b1;
assign has_unknown= !all_known;
assign bus_if_known= all_known ? bus : 8'h00;
endmodule