kernel/gdt_asm.s


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%include "const.inc"

global gdt_flush

section .text:           ; start of the text (code) section
align 4                  ; the code must be 4 byte aligned

gdt_flush:
    mov     eax,[esp+4]  ; Get the pointer to the GDT, passed as a parameter.
    lgdt    [eax]        ; Load the new GDT pointer
    mov     ax,GDT_KERNEL_DATA_SELECTOR   ; offset in the GDT of the kernel data segment
    mov     ds,ax        ; Load all data segment selectors
    mov     es,ax
    mov     fs,ax
    mov     gs,ax
    mov     ss,ax
    jmp     GDT_KERNEL_CODE_SELECTOR:.flush  ; far jump [selector:offset]
.flush:
ret