s390x: raise CPU hotplug irq after really hotplugged

Let's move it into the machine, so we trigger the IRQ after setting
ms->possible_cpus (which SCLP uses to construct the list of
online CPUs).

This also fixes a problem reported by Thomas Huth, whereby qemu can be
crashed using the none machine

qemu-s390x-softmmu -M none -monitor stdio
-> device_add qemu-s390-cpu
Reviewed-by: NChristian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NDavid Hildenbrand <david@redhat.com>
Message-Id: <20170928134609.16985-3-david@redhat.com>
Signed-off-by: NCornelia Huck <cohuck@redhat.com>

hw/s390x/s390-virtio-ccw.c

@@ -307,6 +307,10 @@ static void s390_cpu_plug(HotplugHandler *hotplug_dev,
 
     g_assert(!ms->possible_cpus->cpus[cpu->env.core_id].cpu);
     ms->possible_cpus->cpus[cpu->env.core_id].cpu = OBJECT(dev);
+
+    if (dev->hotplugged) {
+        raise_irq_cpu_hotplug();
+    }
 }
 
 static void s390_machine_reset(void)

target/s390x/cpu.c

@@ -41,7 +41,6 @@
 #include "hw/hw.h"
 #include "sysemu/arch_init.h"
 #include "sysemu/sysemu.h"
-#include "hw/s390x/sclp.h"
 #endif
 
 #define CR0_RESET       0xE0UL
@@ -227,13 +226,6 @@ static void s390_cpu_realizefn(DeviceState *dev, Error **errp)
 #endif
 
     scc->parent_realize(dev, &err);
-
-#if !defined(CONFIG_USER_ONLY)
-    if (dev->hotplugged) {
-        raise_irq_cpu_hotplug();
-    }
-#endif
-
 out:
     error_propagate(errp, err);
 }