From 111e9b24138cf3e1b19ee2ee95774f6f3811de75 Mon Sep 17 00:00:00 2001
From: Jan Beulich <jbeulich@suse.com>
Date: Tue, 6 Mar 2012 16:41:41 +0100
Subject: [PATCH] x86/cpuidle: deny access to the I/O port used for EM_SYSIO

Nothing, not even Dom0, should fiddle with this.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
Acked-by: Keir Fraser <keir@xen.org>
---
 xen/arch/x86/acpi/cpu_idle.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/xen/arch/x86/acpi/cpu_idle.c b/xen/arch/x86/acpi/cpu_idle.c
index bc824e88c0..a675867f24 100644
--- a/xen/arch/x86/acpi/cpu_idle.c
+++ b/xen/arch/x86/acpi/cpu_idle.c
@@ -45,6 +45,7 @@
 #include <xen/irq.h>
 #include <asm/cache.h>
 #include <asm/io.h>
+#include <asm/iocap.h>
 #include <asm/hpet.h>
 #include <asm/processor.h>
 #include <xen/pmstat.h>
@@ -907,6 +908,9 @@ static void set_cx(
             cx->entry_method = ACPI_CSTATE_EM_HALT;
         break;
     case ACPI_ADR_SPACE_SYSTEM_IO:
+        if ( ioports_deny_access(dom0, cx->address, cx->address) )
+            printk(XENLOG_WARNING "Could not deny access to port %04x\n",
+                   cx->address);
         cx->entry_method = ACPI_CSTATE_EM_SYSIO;
         break;
     default:
-- 
2.30.2