44. Bus Error Checker

How do you plan to solve it?

module error_checker_xz (bus, all_known, has_unknown, bus_if_known);
input [7:0] bus;
output all_known, has_unknown;
output [7:0] bus_if_known;
wire bus_has_zero;
assign bus_has_zero= (^bus === 1'bx);
assign all_known = ~bus_has_zero;
assign has_unknown = bus_has_zero;
assign bus_if_known = all_known? bus:8'h00;
endmodule