Question

我刚刚在qemu完成了更高的哈尔夫。但由于某种原因，我给出了虚拟盒子和Bochs的错误：

entry point isnt in a segment.

please press any key to continue . . .

但是在Qemu它运作良好。那么这是我的链接器脚本，我在其中定义了我的入口点：

/* The bootloader will look at this image and start execution at the symbol
   designated as the entry point. */
ENTRY(loader)

SECTIONS {
   /* The kernel will live at 3GB + 1MB in the virtual
      address space, which will be mapped to 1MB in the
      physical address space. */
   . = 0xC0100000;


   .text ALIGN (0x1000) : AT(ADDR(.text) - 0xC0000000) {
       *(.multiboot)
       *(.text)
       *(.rodata*)
   }

   .data ALIGN (0x1000) : AT(ADDR(.data) - 0xC0000000) {
        start_ctors = .;
        KEEP(*( .init_array ));
        KEEP(*(SORT_BY_INIT_PRIORITY( .init_array.* )));
        end_ctors = .;
        *(.data)
   }

   .bss : AT(ADDR(.bss) - 0xC0000000) {
       _sbss = .;
       *(COMMON)
       *(.bss)
       _ebss = .;
   }
}

和我的boot.asm（GRUB）：

;Global MultiBoot Kernel Recongnzation
MAGIC equ 0x1badb002
FLAGS equ (1<<0 | 1<<1)
CHECKSUM equ -(MAGIC + FLAGS)


;Putting in object file
section .multiboot
    dd MAGIC
    dd FLAGS
    dd CHECKSUM

section .data

KERNEL_VIRTUAL_BASE equ 0xC0000000                  ; 3GB
KERNEL_PAGE_NUMBER equ (KERNEL_VIRTUAL_BASE >> 22)  ; Page directory index of kernel's 4MB PTE.

align 0x1000
BootPageDirectory:
    ; This page directory entry identity-maps the first 4MB of the 32-bit physical address space.
    ; All bits are clear except the following:
    ; bit 7: PS The kernel page is 4MB.
    ; bit 1: RW The kernel page is read/write.
    ; bit 0: P  The kernel page is present.
    ; This entry must be here -- otherwise the kernel will crash immediately after paging is
    ; enabled because it can't fetch the next instruction! It's ok to unmap this page later.
    dd 0x00000083
    times (KERNEL_PAGE_NUMBER - 1) dd 0                 ; Pages before kernel space.
    ; This page directory entry defines a 4MB page containing the kernel.
    dd 0x00000083
    times (1024 - KERNEL_PAGE_NUMBER - 1) dd 0  ; Pages after the kernel image.


section .text
    extern kernelMain
    extern callConstructors
    extern page_directory
    extern pages_init
    ; reserve initial kernel stack space -- that's 16k.
    STACKSIZE equ 0x4000
    ; setting up entry point for linker
    loader equ (_loader - 0xC0000000)
    global loader

        _loader:
                    ;Enable Paging START

                    ; NOTE: Until paging is set up, the code must be position-independent and use physical
                    ; addresses, not virtual ones!
                    mov ecx, (BootPageDirectory - KERNEL_VIRTUAL_BASE)
                    mov cr3, ecx                                        ; Load Page Directory Base Register.

                    mov ecx, cr4
                    or ecx, 0x00000010                          ; Set PSE bit in CR4 to enable 4MB pages.
                    mov cr4, ecx

                    mov ecx, cr0
                    or ecx, 0x80000000                          ; Set PG bit in CR0 to enable paging.
                    mov cr0, ecx


                    lea ebx, [higherhalf]
                    jmp ebx

        higherhalf:
                ; Unmap the identity-mapped first 4MB of physical address space. It should not be needed
                ; anymore.
                mov dword [BootPageDirectory], 0
                invlpg [0]

                mov esp, stack            ; set up the stack
                call callConstructors

                push eax
                push ebx
                call kernelMain
                jmp _eof

        _eof:
             cli
             hlt 
             jmp _eof


section .bss
align 32
stack:
    resb STACKSIZE      ; reserve 16k stack on a uint64_t boundary

以下是我的操作系统的完整源代码：https://github.com/amanuel2/OS_MIRROR。帮助将不胜感激。

Answer 1

这解决了这个问题，当我摆脱了equ语句，并从入口声明开始：

toList()

得到OsDev Wiki的帮助：http://f.osdev.org/viewtopic.php?f=1&t=28796。

入口点不在细分中

1 个答案: