[Qemu-devel] [PATCH] hostmem: fix crash when querying empty host-nodes property via QMP

[Igor Mammedov <imammedo@redhat.com>]

QEMU will crashes with
 qapi/qobject-output-visitor.c:210: qobject_output_complete: Assertion `qov->root && ((&qov->stack)->slh_first == ((void *)0))' failed
when trying to get value of empty hostmem.host-nodes property.

Fix it by calling visitor even if host-nodes wasn't set
before exiting from property getter to return empty list.

Signed-off-by: Igor Mammedov <imammedo@redhat.com>
---
 backends/hostmem.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/backends/hostmem.c b/backends/hostmem.c
index 0c8ef17..fe14be5 100644
--- a/backends/hostmem.c
+++ b/backends/hostmem.c
@@ -86,7 +86,7 @@ host_memory_backend_get_host_nodes(Object *obj, Visitor *v, const char *name,
 
     value = find_first_bit(backend->host_nodes, MAX_NODES);
     if (value == MAX_NODES) {
-        return;
+        goto ret;
     }
 
     *node = g_malloc0(sizeof(**node));
@@ -104,6 +104,7 @@ host_memory_backend_get_host_nodes(Object *obj, Visitor *v, const char *name,
         node = &(*node)->next;
     } while (true);
 
+ret:
     visit_type_uint16List(v, name, &host_nodes, errp);
 }
 
-- 
2.7.4