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Higherhalf kernel error

Posted: Sat Jul 28, 2007 11:57 pm
by hanumant
I have the following code in start.asm
SECTION .data
/***some data***/
SECTION .bss
_sys_stack : resb 8192
SECTION .text
global start ....

actually I was trying the higherhalf kerenl tutorial, but it requires the SECTION directive (SECTION .setup)which is not supported by aout format,
so I changed it to be contained in the data section(the defnintion of trickgdt).
and in my linker I am linking kernel at C0000000. Anyways when i run the linker it gives me the following output

start.o:start.o:(.text+0x40): undefined reference to `bss'

My assembly levelskills arent all that good , can someone tell me what i am doing wrong

PS I am using NASM and DJGPP provided linker (doesn't support ELF format for target, so I cant use the linker script in the tutorial)

Posted: Sun Jul 29, 2007 10:20 am
by frank
Well I would actually recommend the COFF format when using NASM with DJGPP.

Also where are you referencing bss in start.asm?