From 75b78273752b2679507689945300aa326dbfd209 Mon Sep 17 00:00:00 2001
From: Jeremy Soller <jackpot51@gmail.com>
Date: Mon, 7 Feb 2022 20:19:40 -0700
Subject: [PATCH] Load gdt before and after thunk
---
asm/x86-unknown-none/thunk.asm | 6 ++++++
1 file changed, 6 insertions(+)
diff --git a/asm/x86-unknown-none/thunk.asm b/asm/x86-unknown-none/thunk.asm
index 0e47f9d..16a3597 100644
--- a/asm/x86-unknown-none/thunk.asm
+++ b/asm/x86-unknown-none/thunk.asm
@@ -32,6 +32,9 @@ thunk:
; save esp
mov [.esp], esp
+ ; load gdt
+ lgdt [gdtr]
+
; far jump to protected mode 16-bit
jmp gdt.pm16_code:.pm16
@@ -121,6 +124,9 @@ USE16
; save registers
pushad
+ ; load gdt (BIOS sometimes overwrites this)
+ lgdt [gdtr]
+
; restore cr0, will enable protected mode
mov eax, [.cr0]
mov cr0, eax
--
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