Re: [PATCH] kobject: make sure kobj->ktype is set before kobject_init

Kay Sievers
2007-11-29T19:52:57Z

On Thu, 2007-11-29 at 14:05 -0500, Alan Stern wrote:
> On Thu, 29 Nov 2007, Kay Sievers wrote:
>
> > Your error scenario confirmed my initial concern about suggesting
> > kobject_put() to clean up an initialized kobject.
> >
> > We should probably make kobject_cleanup() free only the resources taken
> > by kobject_init(), and use kobject_cleanup() instead of kobject_put()?
>
> My conclusion is different. We should make kobject_init() not consume
> any resources at all; just initialize various fields. That way it
> would be okay to call either kfree() or kobject_put() on an initialized
> kobject. And then when something like device_register() fails, the
> caller would know the proper thing to do would be to call the put()
> routine, always.
>
> Of course, once the name has been assigned, only kobject_put() should
> be used.

Now we just move the exactly the same problem from _init() to
_set_name(). To free the name of an unregistered we would need to call
_put() which free()'s the whole object again. :)

> There's another good reason for not assigning the name in
> kobject_init(): Code that uses kobjects (like the driver core) doesn't
> set the name until later.

That can be done at any stage, I guess. We will rip out the name in the
struct device anyway.

Kay