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Subject: Re: [PATCH] kobject: make sure kobj->ktype is set before
	kobject_init
From: Kay Sievers <kay.sievers@vrfy.org>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Cornelia Huck <cornelia.huck@de.ibm.com>, Greg KH <greg@kroah.com>,
       Kernel development list <linux-kernel@vger.kernel.org>,
       Jonathan Corbet <corbet@lwn.net>,
       Randy Dunlap <randy.dunlap@oracle.com>
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Date: Thu, 29 Nov 2007 20:51:23 +0100
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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