2 files changed, 29 insertions, 10 deletions

diff --git a/arch/x86/xen/setup.c b/arch/x86/xen/setup.c
index f52f3855fb6b..bea3d4f779db 100644
--- a/arch/x86/xen/setup.c
+++ b/arch/x86/xen/setup.c
@@ -91,19 +91,25 @@ static void __init fiddle_vdso(void)
         *mask |= 1 << VDSO_NOTE_NONEGSEG_BIT;
 }
 
-void xen_enable_sysenter(void)
+static __cpuinit int register_callback(unsigned type, const void *func)
 {
-        int cpu = smp_processor_id();
-        extern void xen_sysenter_target(void);
-        /* Mask events on entry, even though they get enabled immediately */
-        static struct callback_register sysenter = {
-                .type = CALLBACKTYPE_sysenter,
-                .address = XEN_CALLBACK(__KERNEL_CS, xen_sysenter_target),
+        struct callback_register callback = {
+                .type = type,
+                .address = XEN_CALLBACK(__KERNEL_CS, func),
                 .flags = CALLBACKF_mask_events,
         };
 
+        return HYPERVISOR_callback_op(CALLBACKOP_register, &callback);
+}
+
+void __cpuinit xen_enable_sysenter(void)
+{
+        int cpu = smp_processor_id();
+        extern void xen_sysenter_target(void);
+
         if (!boot_cpu_has(X86_FEATURE_SEP) ||
-            HYPERVISOR_callback_op(CALLBACKOP_register, &sysenter) != 0) {
+            register_callback(CALLBACKTYPE_sysenter,
+                              xen_sysenter_target) != 0) {
                 clear_cpu_cap(&cpu_data(cpu), X86_FEATURE_SEP);
                 clear_cpu_cap(&boot_cpu_data, X86_FEATURE_SEP);
         }
@@ -120,8 +126,9 @@ void __init xen_arch_setup(void)
         if (!xen_feature(XENFEAT_auto_translated_physmap))
                 HYPERVISOR_vm_assist(VMASST_CMD_enable, VMASST_TYPE_pae_extended_cr3);
 
-        HYPERVISOR_set_callbacks(__KERNEL_CS, (unsigned long)xen_hypervisor_callback,
-                                 __KERNEL_CS, (unsigned long)xen_failsafe_callback);
+        if (register_callback(CALLBACKTYPE_event, xen_hypervisor_callback) ||
+            register_callback(CALLBACKTYPE_failsafe, xen_failsafe_callback))
+                BUG();
 
         xen_enable_sysenter();
 
diff --git a/include/asm-x86/xen/hypercall.h b/include/asm-x86/xen/hypercall.h
index d0c5dedcb001..25366641f3f8 100644
--- a/include/asm-x86/xen/hypercall.h
+++ b/include/asm-x86/xen/hypercall.h
@@ -226,6 +226,7 @@ HYPERVISOR_stack_switch(unsigned long ss, unsigned long esp)
         return _hypercall2(int, stack_switch, ss, esp);
 }
 
+#ifdef CONFIG_X86_32
 static inline int
 HYPERVISOR_set_callbacks(unsigned long event_selector,
                          unsigned long event_address,
@@ -236,6 +237,17 @@ HYPERVISOR_set_callbacks(unsigned long event_selector,
                            event_selector, event_address,
                            failsafe_selector, failsafe_address);
 }
+#else  /* CONFIG_X86_64 */
+static inline int
+HYPERVISOR_set_callbacks(unsigned long event_address,
+                        unsigned long failsafe_address,
+                        unsigned long syscall_address)
+{
+        return _hypercall3(int, set_callbacks,
+                           event_address, failsafe_address,
+                           syscall_address);
+}
+#endif  /* CONFIG_X86_{32,64} */
 
 static inline int
 HYPERVISOR_callback_op(int cmd, void *arg)