Re: [Qemu-devel] [PATCH] qdev: unparent device when fails to set properties

[Hu Tao]

On Tue, Dec 31, 2013 at 04:06:57PM +0800, Amos Kong wrote:
> Test steps:
>   (qemu) device_add e1000,addr=adsf
>   Property 'e1000.addr' doesn't take value 'adsf'
>   (qemu) info qtree
> Then qemu crashed.
> 
> When it fails to set properties, qdev's parent is already set, but the
> object hasn't been added to parent object, object_unparent() won't
> unparent the device. This patch unparents device in the mediacy.
> 
> Signed-off-by: Amos Kong <address@hidden>
> ---
>  qdev-monitor.c | 4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
> 
> diff --git a/qdev-monitor.c b/qdev-monitor.c
> index dc37a43..3d8b4f4 100644
> --- a/qdev-monitor.c
> +++ b/qdev-monitor.c
> @@ -527,7 +527,9 @@ DeviceState *qdev_device_add(QemuOpts *opts)
>          dev->id = id;
>      }
>      if (qemu_opt_foreach(opts, set_property, dev, 1) != 0) {
> -        object_unparent(OBJECT(dev));
> +        if (OBJECT(dev)->class->unparent) {
> +            (OBJECT(dev)->class->unparent)(OBJECT(dev));
> +        }

This means object_unparent()(or device_unparent()) doesn't handle
incompletely initialized object correctly. How about fix it in
object_unparent()/device_unparent()?

BTW, it must be commit e0a83fc2c1582dc8 introdues the problem.