xen/panic: use xen_reboot and fix smp_send_stop

Offline vcpu when using stop_self.
Signed-off-by: NIan Campbell <ian.campbell@citrix.com>
Signed-off-by: NJeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com>

arch/x86/xen/enlighten.c

@@ -1043,10 +1043,7 @@ static void xen_crash_shutdown(struct pt_regs *regs)
 static int
 xen_panic_event(struct notifier_block *this, unsigned long event, void *ptr)
 {
-	struct sched_shutdown r = { .reason = SHUTDOWN_crash};
-
-	if (HYPERVISOR_sched_op(SCHEDOP_shutdown, &r))
-		BUG();
+	xen_reboot(SHUTDOWN_crash);
 	return NOTIFY_DONE;
 }
 

arch/x86/xen/smp.c

@@ -394,6 +394,8 @@ static void stop_self(void *v)
 	load_cr3(swapper_pg_dir);
 	/* should set up a minimal gdt */
 
+	set_cpu_online(cpu, false);
+
 	HYPERVISOR_vcpu_op(VCPUOP_down, cpu, NULL);
 	BUG();
 }