[Qemu-devel] [PATCH] hw/sparc64/sun4u: Fix introspection by converting prom instance_init to realize

[Thomas Huth <thuth@redhat.com>]

The instance_init function of devices should always succeed to be able
to introspect the device. However, the instance_init function of the
"openprom" device can currently fail, for example like this:

$ echo "{'execute':'qmp_capabilities'}"\
       "{'execute':'device-list-properties',"\
       " 'arguments':{'typename':'openprom'}}" \
       | sparc64-softmmu/qemu-system-sparc64 -M sun4v,accel=qtest -qmp stdio
{"QMP": {"version": {"qemu": {"micro": 91, "minor": 11, "major": 2},
 "package": "build-all"}, "capabilities": []}}
{"return": {}}
RAMBlock "sun4u.prom" already registered, abort!
Aborted (core dumped)

This should not happen. Fix this problem by moving the affected code from
instance_init into a realize function instead.

Signed-off-by: Thomas Huth <thuth@redhat.com>
---
 hw/sparc64/sun4u.c | 18 ++++++++++++------
 1 file changed, 12 insertions(+), 6 deletions(-)

diff --git a/hw/sparc64/sun4u.c b/hw/sparc64/sun4u.c
index 2044a52..d62f5a2 100644
--- a/hw/sparc64/sun4u.c
+++ b/hw/sparc64/sun4u.c
@@ -425,13 +425,19 @@ static void prom_init(hwaddr addr, const char *bios_name)
     }
 }
 
-static void prom_init1(Object *obj)
+static void prom_realize(DeviceState *ds, Error **errp)
 {
-    PROMState *s = OPENPROM(obj);
-    SysBusDevice *dev = SYS_BUS_DEVICE(obj);
+    PROMState *s = OPENPROM(ds);
+    SysBusDevice *dev = SYS_BUS_DEVICE(ds);
+    Error *local_err = NULL;
+
+    memory_region_init_ram_nomigrate(&s->prom, OBJECT(ds), "sun4u.prom",
+                                     PROM_SIZE_MAX, &local_err);
+    if (local_err) {
+        error_propagate(errp, local_err);
+        return;
+    }
 
-    memory_region_init_ram_nomigrate(&s->prom, obj, "sun4u.prom", PROM_SIZE_MAX,
-                           &error_fatal);
     vmstate_register_ram_global(&s->prom);
     memory_region_set_readonly(&s->prom, true);
     sysbus_init_mmio(dev, &s->prom);
@@ -446,6 +452,7 @@ static void prom_class_init(ObjectClass *klass, void *data)
     DeviceClass *dc = DEVICE_CLASS(klass);
 
     dc->props = prom_properties;
+    dc->realize = prom_realize;
 }
 
 static const TypeInfo prom_info = {
@@ -453,7 +460,6 @@ static const TypeInfo prom_info = {
     .parent        = TYPE_SYS_BUS_DEVICE,
     .instance_size = sizeof(PROMState),
     .class_init    = prom_class_init,
-    .instance_init = prom_init1,
 };
 
 
-- 
1.8.3.1