From 6ef153b6ca0180dcbba57ad4d2b62c37d4f4273e Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Mon, 30 Oct 2023 12:23:22 +0200
Subject: [PATCH] Kernel: Enable Write Protect. This seems to be good for
 security

---
 kernel/arch/x86_64/PageTable.cpp | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/kernel/arch/x86_64/PageTable.cpp b/kernel/arch/x86_64/PageTable.cpp
index ef0db19f..861522a0 100644
--- a/kernel/arch/x86_64/PageTable.cpp
+++ b/kernel/arch/x86_64/PageTable.cpp
@@ -92,6 +92,13 @@ namespace Kernel
 			s_has_pge = true;
 		}
 
+		// enable write protect to kernel
+		asm volatile(
+			"movq %cr0, %rax;"
+			"orq $0x10000, %rax;"
+			"movq %rax, %cr0;"
+		);
+
 		ASSERT(s_kernel == nullptr);
 		s_kernel = new PageTable();
 		ASSERT(s_kernel);