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Subject: Re: [patch 1/7] slab: introduce kzfree()
From: Pekka Enberg <penberg@cs.helsinki.fi>
To: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: David Vrabel <david.vrabel@csr.com>, Johannes Weiner <hannes@cmpxchg.org>,
       Andrew Morton <akpm@linux-foundation.org>,
       Chas Williams <chas@cmf.nrl.navy.mil>,
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       Nick Piggin <npiggin@suse.de>
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Date: Thu, 19 Feb 2009 11:13:37 +0200
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On Wed, 2009-02-18 at 10:50 +0000, David Vrabel wrote:
> > > Johannes Weiner wrote:
> > > > +void kzfree(const void *p)
> > > 
> > > Shouldn't this be void * since it writes to the memory?
> > 
> > No. kfree() writes to the memory as well to update freelists, poisoning
> > and such so kzfree() is not at all different from it.

On Thu, 2009-02-19 at 10:22 +0900, KOSAKI Motohiro wrote:
> I don't think so. It's debetable thing.
> 
> poisonig is transparent feature from caller.
> but the caller of kzfree() know to fill memory and it should know.

Debatable, sure, but doesn't seem like a big enough reason to make
kzfree() differ from kfree().