section .text 
    global _start

_start:
    mov eax, 15
    mov ebx, 1
lb:
    imul eax, ebx
    inc ebx
    cmp ebx,15
    jl lb

    mov ebx, eax
    mov eax, 1
    int 80h

I am new to assembly, I have this code to calculate factorial of 15, I know exit code in ebx should be between 0 and 255 but I will run this in gdb, but this isn’t working properly help and also how should i output this value in kernel, give a simple explanation I’m new