softmmu: fix crash with invalid -M memory-backend=

Fixes: fe64d06afc1c5d895f220c268cfe4d5f1e65d44e ("vl.c: ensure that
ram_size matches size of machine.memory-backend")
Signed-off-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Reviewed-by: Igor Mammedov <imammedo@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200309145155.168942-1-marcandre.lureau@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/softmmu/vl.c b/softmmu/vl.c
index a331fb532112320883f99f423d80cb510150f211..796a77e2345d1ade69ce1af49c049632e4e38dd7 100644 (file)
--- a/softmmu/vl.c
+++ b/softmmu/vl.c
@@ -4298,6 +4298,11 @@ void qemu_init(int argc, char **argv, char **envp)
 
         backend = object_resolve_path_type(current_machine->ram_memdev_id,
                                            TYPE_MEMORY_BACKEND, NULL);
+        if (!backend) {
+            error_report("Memory backend '%s' not found",
+                         current_machine->ram_memdev_id);
+            exit(EXIT_FAILURE);
+        }
         backend_size = object_property_get_uint(backend, "size",  &error_abort);
         if (have_custom_ram_size && backend_size != ram_size) {
                 error_report("Size specified by -m option must match size of "