2 files changed, 11 insertions, 9 deletions

diff --git a/arch/x86/xen/enlighten.c b/arch/x86/xen/enlighten.c
index bd3554934613..7250bef7f49e 100644
--- a/arch/x86/xen/enlighten.c
+++ b/arch/x86/xen/enlighten.c
@@ -1095,6 +1095,8 @@ static void __init xen_setup_stackprotector(void)
 /* First C function to be called on Xen boot */
 asmlinkage void __init xen_start_kernel(void)
 {
+        struct physdev_set_iopl set_iopl;
+        int rc;
         pgd_t *pgd;
 
         if (!xen_start_info)
@@ -1209,10 +1211,18 @@ asmlinkage void __init xen_start_kernel(void)
 #else
         pv_info.kernel_rpl = 0;
 #endif
-
         /* set the limit of our address space */
         xen_reserve_top();
 
+        /* We used to do this in xen_arch_setup, but that is too late on AMD
+         * were early_cpu_init (run before ->arch_setup()) calls early_amd_init
+         * which pokes 0xcf8 port.
+         */
+        set_iopl.iopl = 1;
+        rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
+        if (rc != 0)
+                xen_raw_printk("physdev_op failed %d\n", rc);
+
 #ifdef CONFIG_X86_32
         /* set up basic CPUID stuff */
         cpu_detect(&new_cpu_data);
diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index 630fb53c95f3..38fdffaa71d3 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -336,9 +336,6 @@ void __cpuinit xen_enable_syscall(void)
 
 void __init xen_arch_setup(void)
 {
-        struct physdev_set_iopl set_iopl;
-        int rc;
-
         xen_panic_handler_init();
 
         HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_4gb_segments);
@@ -355,11 +352,6 @@ void __init xen_arch_setup(void)
         xen_enable_sysenter();
         xen_enable_syscall();
 
-        set_iopl.iopl = 1;
-        rc = HYPERVISOR_physdev_op(PHYSDEVOP_set_iopl, &set_iopl);
-        if (rc != 0)
-                printk(KERN_INFO "physdev_op failed %d\n", rc);
-
 #ifdef CONFIG_ACPI
         if (!(xen_start_info->flags & SIF_INITDOMAIN)) {
                 printk(KERN_INFO "ACPI in unprivileged domain disabled\n");