From 032fc3b190351a31f7f82c634c3b80651c412a7f Mon Sep 17 00:00:00 2001
From: Reto Buerki <reet@codelabs.ch>
Date: Wed, 11 Feb 2015 15:46:30 +0100
Subject: [PATCH] hw_x86_64: Enable IA-32e mode and execute-disable

Set bits 8 (LME) and 11 (NXE) in the IA32_EFER MSR to enable IA-32e mode
and execute-disable.
---
 repos/base-hw/src/core/spec/x86_64/kernel/crt0.s | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/repos/base-hw/src/core/spec/x86_64/kernel/crt0.s b/repos/base-hw/src/core/spec/x86_64/kernel/crt0.s
index cfefe4e19..864754984 100644
--- a/repos/base-hw/src/core/spec/x86_64/kernel/crt0.s
+++ b/repos/base-hw/src/core/spec/x86_64/kernel/crt0.s
@@ -38,6 +38,13 @@
 	leal _kernel_pml4, %eax
 	mov %eax, %cr3
 
+	/* Enable IA-32e mode and execute-disable */
+	movl $0xc0000080, %ecx
+	rdmsr
+	btsl $8, %eax
+	btsl $11, %eax
+	wrmsr
+
 	/*
 	 * Install initial temporary environment that is replaced later by the
 	 * environment that init_main_thread creates.