键盘中断处理程序在系统iso中不起作用

Question

我正在尝试使用OSDev和其他人编写操作系统。现在，我被困在制作键盘中断处理程序。当我编译我的操作系统并使用qemu-system-i386 -kernel kernel/myos.kernel运行内核时，一切都很完美。当我将所有内容都放入ISO映像并尝试使用qemu-system-i386 -cdrom myos.iso运行时，当我按下某个键时它会重新启动。我认为这是由我的中断处理程序中的一些问题或IDT条目错误引起的。

我的键盘处理程序（AT＆T语法）：

.globl   keyboard_handler
.align   4

keyboard_handler:

    pushal
    cld 
    call keyboard_handler_main
    popal
    iret

我在C中的主要处理程序：

void keyboard_handler_main(void) {
    unsigned char status;
  char keycode;
    /* write EOI */
    write_port(0x20, 0x20);

    status = read_port(KEYBOARD_STATUS_PORT);
    /* Lowest bit of status will be set if buffer is not empty */
    if (status & 0x01) {
        keycode = read_port(KEYBOARD_DATA_PORT);
        if(keycode < 0)
            return;

        if(keycode == ENTER_KEY_CODE) {
            printf("
");
            return;
        }
        printf("%c", keyboard_map[(unsigned char) keycode]);
    }
}

我用来加载的C函数：

void idt_init(void)
{
    //unsigned long keyboard_address;
    unsigned long idt_address;
    unsigned long idt_ptr[2];

    auto keyboard_address = (*keyboard_handler);

    IDT[0x21].offset_lowerbits = keyboard_address & 0xffff;
    IDT[0x21].selector = KERNEL_CODE_SEGMENT_OFFSET;
    IDT[0x21].zero = 0;
    IDT[0x21].type_attr = INTERRUPT_GATE;
    IDT[0x21].offset_higherbits = (keyboard_address & 0xffff0000) >> 16;

    /*     Ports
    *    PIC1   PIC2
    *Command 0x20   0xA0
    *Data    0x21   0xA1
    */

    write_port(0x20 , 0x11);
    write_port(0xA0 , 0x11);

    write_port(0x21 , 0x20);
    write_port(0xA1 , 0x28);

    write_port(0x21 , 0x00);
    write_port(0xA1 , 0x00);

    write_port(0x21 , 0x01);
    write_port(0xA1 , 0x01);

    write_port(0x21 , 0xff);
    write_port(0xA1 , 0xff);

    idt_address = (unsigned long)IDT ;
    idt_ptr[0] = (sizeof (struct IDT_entry) * IDT_SIZE) + ((idt_address & 0xffff) << 16);
    idt_ptr[1] = idt_address >> 16 ;

    load_idt(idt_ptr);

    printf("%s
", "loadd");
}

文件的组织方式与OSDev's Meaty Skeleton相同。我有一个不同的bootloader。