spapr_cpu_core: instantiate CPUs separately

The current code assumes that only the CPU core object holds a
reference on each individual CPU object, and happily frees their
allocated memory when the core is unrealized. This is dangerous
as some other code can legitimely keep a pointer to a CPU if it
calls object_ref(), but it would end up with a dangling pointer.

Let's allocate all CPUs with object_new() and let QOM free them
when their reference count reaches zero. This greatly simplify the
code as we don't have to fiddle with the instance size anymore.

Signed-off-by: Greg Kurz <groug@kaod.org>
Acked-by: Igor Mammedov <imammedo@redhat.com>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

1 files changed, 3 insertions, 8 deletions

diff --git a/hw/ppc/spapr.c b/hw/ppc/spapr.c
index 8881f2f1e8..f1b96a4e92 100644
--- a/hw/ppc/spapr.c
+++ b/hw/ppc/spapr.c
@@ -3180,12 +3180,10 @@ void spapr_core_release(DeviceState *dev)
 
     if (smc->pre_2_10_has_unused_icps) {
         sPAPRCPUCore *sc = SPAPR_CPU_CORE(OBJECT(dev));
-        sPAPRCPUCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(OBJECT(cc));
-        size_t size = object_type_get_instance_size(scc->cpu_type);
         int i;
 
         for (i = 0; i < cc->nr_threads; i++) {
-            CPUState *cs = CPU(sc->threads + i * size);
+            CPUState *cs = CPU(sc->threads[i]);
 
             pre_2_10_vmstate_register_dummy_icp(cs->cpu_index);
         }
@@ -3231,7 +3229,7 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     sPAPRMachineClass *smc = SPAPR_MACHINE_CLASS(mc);
     sPAPRCPUCore *core = SPAPR_CPU_CORE(OBJECT(dev));
     CPUCore *cc = CPU_CORE(dev);
-    CPUState *cs = CPU(core->threads);
+    CPUState *cs = CPU(core->threads[0]);
     sPAPRDRConnector *drc;
     Error *local_err = NULL;
     int smt = kvmppc_smt_threads();
@@ -3276,15 +3274,12 @@ static void spapr_core_plug(HotplugHandler *hotplug_dev, DeviceState *dev,
     core_slot->cpu = OBJECT(dev);
 
     if (smc->pre_2_10_has_unused_icps) {
-        sPAPRCPUCoreClass *scc = SPAPR_CPU_CORE_GET_CLASS(OBJECT(cc));
-        size_t size = object_type_get_instance_size(scc->cpu_type);
         int i;
 
         for (i = 0; i < cc->nr_threads; i++) {
             sPAPRCPUCore *sc = SPAPR_CPU_CORE(dev);
-            void *obj = sc->threads + i * size;
 
-            cs = CPU(obj);
+            cs = CPU(sc->threads[i]);
             pre_2_10_vmstate_unregister_dummy_icp(cs->cpu_index);
         }
     }