From 8fcea7951b724f5316b84421dc6b8bdfa6beb391 Mon Sep 17 00:00:00 2001
From: Philipp Oppermann <dev@phil-opp.com>
Date: Thu, 13 Apr 2017 18:35:00 +0200
Subject: [PATCH] Recursive map the P4 table

---
 src/arch/x86_64/boot.asm | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/src/arch/x86_64/boot.asm b/src/arch/x86_64/boot.asm
index 6a9cb31..c82b6df 100644
--- a/src/arch/x86_64/boot.asm
+++ b/src/arch/x86_64/boot.asm
@@ -85,6 +85,11 @@ check_long_mode:
     jmp error
 
 set_up_page_tables:
+    ; map P4 table recursively
+    mov eax, p4_table
+    or eax, 0b11 ; present + writable
+    mov [p4_table + 511 * 8], eax
+
     ; map first P4 entry to P3 table
     mov eax, p3_table
     or eax, 0b11 ; present + writable