From 85cc696ea5120982072cd5d3ef7dfd757088a7e9 Mon Sep 17 00:00:00 2001
From: Lizzy Fleckenstein <eliasfleckenstein@web.de>
Date: Thu, 7 Dec 2023 15:33:24 +0100
Subject: ensure stack doesn't overwrite MBR during stage1

---
 stage1/main.asm | 6 +++++-
 1 file changed, 5 insertions(+), 1 deletion(-)

diff --git a/stage1/main.asm b/stage1/main.asm
index ce4ead4..f14c1f0 100644
--- a/stage1/main.asm
+++ b/stage1/main.asm
@@ -13,7 +13,7 @@ boot:
 	mov ss, ax
 
 	; init stack
-	mov bp, KSTART ; stack grows down, overwriting MBR
+	mov bp, 0x7C00
 	mov sp, bp
 
 	; print message
@@ -30,6 +30,10 @@ boot:
 	; load stage2 and stage3
 	call load_stages
 
+	; reclaim MBR space for stack
+	mov bp, KSTART
+	mov sp, bp
+
 	; jump into stage2
 	jmp KSTART
 
-- 
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