xen: restore vcpu_info mapping

If we're using vcpu_info mapping, then make sure its restored on all
processors before relasing them from stop_machine.

The only complication is that if this fails, we can't continue because
we've already made assumptions that the mapping is available (baked in
calls to the _direct versions of the functions, for example).

Fortunately this can only happen with a 32-bit hypervisor, which may
possibly run out of mapping space.  On a 64-bit hypervisor, this is a
non-issue.

Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/arch/x86/xen/suspend.c b/arch/x86/xen/suspend.c
index 7620a16..7ab10f6 100644
--- a/arch/x86/xen/suspend.c
+++ b/arch/x86/xen/suspend.c
@@ -26,6 +26,8 @@
 
 void xen_post_suspend(int suspend_cancelled)
 {
+	xen_setup_shared_info();
+
 	if (suspend_cancelled) {
 		xen_start_info->store_mfn =
 			pfn_to_mfn(xen_start_info->store_mfn);
@@ -35,8 +37,8 @@
 #ifdef CONFIG_SMP
 		xen_cpu_initialized_map = cpu_online_map;
 #endif
+		xen_vcpu_restore();
 	}
 
-	xen_setup_shared_info();
 }