This is a regression from commit d2623129a7dec1d3041ad1221dda1ca49c667532 ("qom: Drop parameter @errp of object_property_add() & friends").
(qemu) chardev-add id=null,backend=null (qemu) chardev-add id=null,backend=null Unexpected error in object_property_try_add() at /home/elmarco/src/qemu/qom/object.c:1166: attempt to add duplicate property 'null' to object (type 'container') That case is currently not covered in the test suite, but will be with the queued patch "char: fix use-after-free with dup chardev & reconnect". Signed-off-by: Marc-André Lureau <marcandre.lur...@redhat.com> --- chardev/char.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/chardev/char.c b/chardev/char.c index e3051295ac3..876e41bb592 100644 --- a/chardev/char.c +++ b/chardev/char.c @@ -998,7 +998,10 @@ static Chardev *chardev_new(const char *id, const char *typename, } if (id) { - object_property_add_child(get_chardevs_root(), id, obj); + object_property_try_add_child(get_chardevs_root(), id, obj, &local_err); + if (local_err) { + goto end; + } object_unref(obj); } -- 2.27.0.90.geebb51ba8c