Bran's Kernel Development Tutorial Known Bugs

Several sources - including this Wiki - point to Bran's Kernel Development Tutorial as a starting point. This is all well, but there are some issues with that tutorial that usually make people appear on the forum and asking all the same questions again. This article is meant to preempt those questions, like a "Bran's FAQ" if you like.

As soon as I add strings, things go wrong.

The linker script from Bran's tutorial does not add the rodata sections to the binary, which is where the compiler puts static strings. Use this one instead:

OUTPUT_FORMAT("binary")
ENTRY(start)
phys = 0x00100000;
SECTIONS
{
  .text phys : AT(phys) {
    code = .;
    *(.text)
    *(.rodata)
    . = ALIGN(4096);
  }
  .data : AT(phys + (data - code))
  {
    data = .;
    *(.data)
    . = ALIGN(4096);
  }
  .bss : AT(phys + (bss - code))
  {
    bss = .;
    *(.bss)
    . = ALIGN(4096);
  }
  end = .;
}

If you still have problems, you may need to change the output format of the nasm command in the build.bat to make an ELF file instead of a.out.

References

• http://forum.osdev.org/viewtopic.php?f=8&t=18302