diff options
| -rw-r--r-- | src/boot/boot.asm | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/boot/boot.asm b/src/boot/boot.asm index 75ad05e..0f31c9d 100644 --- a/src/boot/boot.asm +++ b/src/boot/boot.asm @@ -22,8 +22,11 @@ ; make sure we know the location of the stack by setting it on our own ; this stack is only used in real mode in stage 1, so it's growing from -; 0xffff down - mov bp, 0xFFFF +; 0x2000 down, we should really not set it above 0x7c00, as this is +; exacly the place, where we load stage 2 and the kernel to! (was 0xffff, +; which was a really bad idea after the kernel got bigger than roughly +; 32k!) + mov bp, 0x2000 mov sp, bp ; print out some information about CPU mode and BIOS boot drive @@ -170,6 +173,13 @@ MESSAGE_HALTED_REAL: [bits 32] BEGIN_PROTECTED_MODE: +; make sure registers have known values + xor eax, eax + xor ebx, ebx + xor ecx, ecx + xor edx, edx + xor esi, esi + xor edi, edi ; we switched to protected mode mov si, MESSAGE_PROTECTED_MODE |