kvm/apic: fix 2.2->2.1 migration

The wait_for_sipi field is set back to 1 after an INIT, so it was not
effective to reset it in kvm_apic_realize.  Introduce a reset callback
and reset wait_for_sipi there.
Reported-by: NIgor Mammedov <imammedo@redhat.com>
Cc: qemu-stable@nongnu.org
Reviewed-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NPaolo Bonzini <pbonzini@redhat.com>

hw/i386/kvm/apic.c

@@ -171,12 +171,15 @@ static const MemoryRegionOps kvm_apic_io_ops = {
     .endianness = DEVICE_NATIVE_ENDIAN,
 };
 
-static void kvm_apic_realize(DeviceState *dev, Error **errp)
+static void kvm_apic_reset(APICCommonState *s)
 {
-    APICCommonState *s = APIC_COMMON(dev);
-
     /* Not used by KVM, which uses the CPU mp_state instead.  */
     s->wait_for_sipi = 0;
+}
+
+static void kvm_apic_realize(DeviceState *dev, Error **errp)
+{
+    APICCommonState *s = APIC_COMMON(dev);
 
     memory_region_init_io(&s->io_memory, NULL, &kvm_apic_io_ops, s, "kvm-apic-msi",
                           APIC_SPACE_SIZE);
@@ -191,6 +194,7 @@ static void kvm_apic_class_init(ObjectClass *klass, void *data)
     APICCommonClass *k = APIC_COMMON_CLASS(klass);
 
     k->realize = kvm_apic_realize;
+    k->reset = kvm_apic_reset;
     k->set_base = kvm_apic_set_base;
     k->set_tpr = kvm_apic_set_tpr;
     k->get_tpr = kvm_apic_get_tpr;

hw/intc/apic_common.c

@@ -178,6 +178,7 @@ bool apic_next_timer(APICCommonState *s, int64_t current_time)
 void apic_init_reset(DeviceState *dev)
 {
     APICCommonState *s = APIC_COMMON(dev);
+    APICCommonClass *info = APIC_COMMON_GET_CLASS(s);
     int i;
 
     if (!s) {
@@ -206,6 +207,10 @@ void apic_init_reset(DeviceState *dev)
         timer_del(s->timer);
     }
     s->timer_expiry = -1;
+
+    if (info->reset) {
+        info->reset(s);
+    }
 }
 
 void apic_designate_bsp(DeviceState *dev)

include/hw/i386/apic_internal.h

@@ -89,6 +89,7 @@ typedef struct APICCommonClass
     void (*external_nmi)(APICCommonState *s);
     void (*pre_save)(APICCommonState *s);
     void (*post_load)(APICCommonState *s);
+    void (*reset)(APICCommonState *s);
 } APICCommonClass;
 
 struct APICCommonState {