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Date: Thu, 26 Apr 2007 17:12:47 +0200
From: Cornelia Huck <cornelia.huck@de.ibm.com>
To: Alan Stern <stern@rowland.harvard.edu>
Cc: Greg KH <greg@kroah.com>, Tejun Heo <htejun@gmail.com>,
       linux-kernel <linux-kernel@vger.kernel.org>,
       Rusty Russell <rusty@rustcorp.com.au>,
       Dmitry Torokhov <dmitry.torokhov@gmail.com>
Subject: Re: [PATCH RFD] alternative kobject release wait mechanism
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On Thu, 26 Apr 2007 10:58:45 -0400 (EDT),
Alan Stern <stern@rowland.harvard.edu> wrote:

> > > > The remove() method must also unset driver_data.
> > > 
> > > It doesn't really have to.  The driver core could do it.
> > 
> > I think it is more consistent if the driver takes care of the fields
> > specifically designed for its usage.
> 
> Yes.  However if the driver forgets to clear the field it shouldn't cause
> a warning.  After all, there won't be any harm; the next driver to bind 
> to the device will just overwrite the driver_data anyway.

Agreed, but it is still a good practice and should be recommended.

> > Yes. Especially since the "gone"-field may be contained in that
> > embedding structure if the subsystem controls it.
> 
> No, no!  The "gone" flag must be in the private data structure.  If it 
> were in a container of the device structure, then it could be overwritten 
> when a different driver binds to the device.

Argl, thinko again. You're right, of course.