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Hey

I've got my operating system to boot into the kernel image, but I don't think the ld linker script is working right. The bootstrap copies the kernel image to 0x1000 , so I have an overlay set up to link the code for that location. Right now, all the kernel does is print a string to the screen, and if I specify an absolute location (i.e print(0x2008)), then it works, but if I specify the variable that points to the data (print(buffer)), then it prints stuff at the wrong location in memory. Also, the trampoline has the same problem: I am currently telling it to jump to an absolute location to enter the kernel code. If I tell it to jump to main, it is linked to jump to 0x0.
The code is compiled with:
nasm trampoline.asm -o trampoline.o -f elf
gcc -ffreestanding -fPIC -c main
ld -M -T link.ld

Here is the linker script:
OUTPUT(kernel.bin)

INPUT(main.o)

ENTRY(start)
OUTPUT_FORMAT("binary")
SECTIONS
{
        OVERLAY : AT (0x1000)
        {
                stage1          
                {
                        trampoline.o(.text)
                        trampoline.o(.data)
                        trampoline.o(.bss)
                }

                .text
                {
                        /* -fPIC requires this */
                        PROVIDE(_GLOBAL_OFFSET_TABLE_ = 0x1000);

                        *(.text)

                        . = ALIGN(4096);
                }

                .data
                {
                        *(.data)
                        *(.bss)
                        *(.rodata)

                        . = ALIGN(4096);
                }
        }
}


Thanks for any help,
Michael VE3MTM

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