[Qemu-ppc] [PATCH RFC 1/4] PPC: TCG: Correct SEGV when smp_threads > 1

[Sam Bobroff]

QEMU currently segfaults on PPC when starting a VM with more than one
thread/core when using TCG. This is not a valid configuration but it
should present an error report rather than crashing.

This seems to have been a latent bug in spapr_cpu_core_realize_child()
recently uncovered by commit 9ed656631d73a7564dfe178ca8c48bf049098aaf.

Correct it by avoiding unparenting when there is no parent.

Signed-off-by: Sam Bobroff <address@hidden>
---
 hw/ppc/spapr_cpu_core.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/hw/ppc/spapr_cpu_core.c b/hw/ppc/spapr_cpu_core.c
index 9fb896b407..a504765506 100644
--- a/hw/ppc/spapr_cpu_core.c
+++ b/hw/ppc/spapr_cpu_core.c
@@ -157,13 +157,14 @@ static void spapr_cpu_core_realize_child(Object *child, 
Error **errp)
     object_property_add_const_link(obj, ICP_PROP_CPU, child, &error_abort);
     object_property_set_bool(obj, true, "realized", &local_err);
     if (local_err) {
-        goto error;
+        goto error_unparent;
     }
 
     return;
 
-error:
+error_unparent:
     object_unparent(obj);
+error:
     error_propagate(errp, local_err);
 }
 
-- 
2.12.1.382.gc0f9c7058