Simplified boot script.

boot.s

@@ -1,58 +1,32 @@
-global start
+; http://wiki.osdev.org/Bare_Bones_with_NASM
-extern kernel_main        ; Allow main() to be called from the assembly code
+MBALIGN  equ  1<<0              ; align loaded modules on page boundaries
-extern start_ctors, end_ctors, start_dtors, end_dtors
+MEMINFO  equ  1<<1              ; provide memory map
- 
+FLAGS    equ  MBALIGN | MEMINFO ; this is the Multiboot 'flag' field
-MODULEALIGN        equ        1<<0
+MAGIC    equ  0x1BADB002        ; 'magic number' lets bootloader find the header
-MEMINFO            equ        1<<1
+CHECKSUM equ -(MAGIC + FLAGS)   ; checksum of above, to prove we are multiboot
-FLAGS              equ        MODULEALIGN | MEMINFO
+
-MAGIC              equ        0x1BADB002
+section .multiboot
-CHECKSUM           equ        -(MAGIC + FLAGS)
- 
-section .text      ; Next is the Grub Multiboot Header
- 
 align 4
-MultiBootHeader:
+	dd MAGIC
-       dd MAGIC
+	dd FLAGS
-       dd FLAGS
+	dd CHECKSUM
-       dd CHECKSUM
+
- 
-STACKSIZE equ 0x4000  ; 16 KiB if you're wondering
- 
-static_ctors_loop:
-   mov ebx, start_ctors
-   jmp .test
-.body:
-   call [ebx]
-   add ebx,4
-.test:
-   cmp ebx, end_ctors
-   jb .body
- 
-start:
-       mov esp, STACKSIZE+stack
- 
-       push eax
-       push ebx
- 
-       call kernel_main
- 
-static_dtors_loop:
-   mov ebx, start_dtors
-   jmp .test
-.body:
-   call [ebx]
-   add ebx,4
-.test:
-   cmp ebx, end_dtors
-   jb .body
- 
- 
-cpuhalt:
-       hlt
-       jmp cpuhalt
- 
 section .bss
-align 32
+align 16
- 
+stack_bottom:
-stack:
+resb 16384 ; 16 KiB
-      resb      STACKSIZE
+stack_top:
+
+section .text
+global _start:function (_start.end - _start)
+_start:
+
+	mov esp, stack_top
+
+	extern kernel_main
+	call kernel_main
+
+	cli
+.hang:	hlt
+	jmp .hang
+.end: