From b9999306a523371512e64b5effaa60e57f8005d9 Mon Sep 17 00:00:00 2001 From: Carlos Fenollosa Date: Thu, 9 Oct 2014 11:42:38 +0200 Subject: [PATCH] lessons 8, 9, 10, entering 32-bit mode --- 09-32bit-gdt/README.md | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/09-32bit-gdt/README.md b/09-32bit-gdt/README.md index 799c494..baee972 100644 --- a/09-32bit-gdt/README.md +++ b/09-32bit-gdt/README.md @@ -19,9 +19,9 @@ but it's good enough to boot, we'll fix this later with a higher language. As a curiosity, the first GDT entry must be `0x00` to make sure that the programmer didn't make any mistakes managing addresses. -Furthermore, since the CPU needs to know how long the GDT is, we'll use +Furthermore, the CPU can't directly load the GDT address, but it requires a meta structure called the "GDT descriptor" with the size (16b) and address -(32b) of our actual GDT. +(32b) of our actual GDT. It is loaded with the `lgdt` operation. Let's directly jump to the GDT code in assembly. Again, to understand all the segment flags, refer to the os-dev.pdf document. The theory for