From 707ebbc81c61eb480d8a51ca61e355e240df1d32 Mon Sep 17 00:00:00 2001
From: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Date: Fri, 27 Mar 2009 11:29:02 -0700
Subject: [PATCH] xen: set _PAGE_NX in __supported_pte_mask before pagetable
 construction

Some 64-bit machines don't support the NX flag in ptes.
Check for NX before constructing the kernel pagetables.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
---
 arch/x86/xen/enlighten.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index da33e0c5870d..80f4c5343495 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -42,6 +42,7 @@
 #include <asm/xen/hypervisor.h>
 #include <asm/fixmap.h>
 #include <asm/processor.h>
+#include <asm/proto.h>
 #include <asm/msr-index.h>
 #include <asm/setup.h>
 #include <asm/desc.h>
@@ -912,7 +913,6 @@ static const struct machine_ops __initdata xen_machine_ops = {
 	.emergency_restart = xen_emergency_restart,
 };
 
-
 /* First C function to be called on Xen boot */
 asmlinkage void __init xen_start_kernel(void)
 {
@@ -980,6 +980,11 @@ asmlinkage void __init xen_start_kernel(void)
 	if (!xen_initial_domain())
 		__supported_pte_mask &= ~(_PAGE_PWT | _PAGE_PCD);
 
+#ifdef CONFIG_X86_64
+	/* Work out if we support NX */
+	check_efer();
+#endif
+
 	/* Don't do the full vcpu_info placement stuff until we have a
 	   possible map and a non-dummy shared_info. */
 	per_cpu(xen_vcpu, 0) = &HYPERVISOR_shared_info->vcpu_info[0];
-- 
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