Re: [PATCH] kobject: Make sure the parent does not get released before its children

[Brendan Higgins]

On Wed, May 13, 2020 at 8:18 AM Heikki Krogerus
<heikki.krogerus@xxxxxxxxxxxxxxx> wrote:
>
> In the function kobject_cleanup(), kobject_del(kobj) is
> called before the kobj->release(). That makes it possible to
> release the parent of the kobject before the kobject itself.
>
> To fix that, adding function __kboject_del() that does
> everything that kobject_del() does except release the parent
> reference. kobject_cleanup() then calls __kobject_del()
> instead of kobject_del(), and separately decrements the
> reference count of the parent kobject after kobj->release()
> has been called.
>
> Reported-by: Naresh Kamboju <naresh.kamboju@xxxxxxxxxx>
> Reported-by: kernel test robot <rong.a.chen@xxxxxxxxx>
> Fixes: 7589238a8cf3 ("Revert "software node: Simplify software_node_release() function"")
> Cc: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
> Cc: Randy Dunlap <rdunlap@xxxxxxxxxxxxx>
> Suggested-by: "Rafael J. Wysocki" <rafael@xxxxxxxxxx>
> Signed-off-by: Heikki Krogerus <heikki.krogerus@xxxxxxxxxxxxxxx>

Reviewed-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>
Tested-by: Brendan Higgins <brendanhiggins@xxxxxxxxxx>