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Subject: Re: Fixing the main programmer thinko with the device model
From: Kay Sievers <kay.sievers@vrfy.org>
To: Greg KH <greg@kroah.com>
Cc: Andi Kleen <andi@firstfloor.org>,
       James Bottomley <James.Bottomley@HansenPartnership.com>,
       "Van De Ven, Arjan" <arjan@linux.intel.com>,
       Al Viro <viro@ZenIV.linux.org.uk>,
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Date: Wed, 26 Mar 2008 06:07:49 +0100
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On Tue, 2008-03-25 at 21:16 -0700, Greg KH wrote:
> On Tue, Mar 25, 2008 at 10:57:32AM +0100, Andi Kleen wrote:
> > James Bottomley <James.Bottomley@HansenPartnership.com> writes:
> > > 
> > > That's true, but irrelevant (and also soon to be untrue if we get rid of
> > > the scsi_device class as you and Kay keep requesting).  The two calls
> > > release references on the actual embedded generic device, it's nothing
> > > to do with entangled lifetime rules.
> > 
> > <heretic thought>Has anybody ever considered just doing away with 
> > the problematic and bug prone and tricky reference counts for kobjects 
> > and switch to a simple garbage collector for them?
> 
> Sure, I have no objection to that.  It's just that the reference count
> "issue" really doesn't seem to be one on sanely designed busses :)

Hmm, what is a "simple garbage collector" here? How could one determine
"reachability" of objects, means: at what point of time do objects
actually become "garbage"? How could one trace in our current kernel
code who still accesses an object, without doing refcounts?

Kay