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Date: Wed, 10 Sep 2014 15:40:10 -0400
From: "Theodore Ts'o" <tytso@mit.edu>
To: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Jiri Kosina <jkosina@suse.cz>, Andrew Morton <akpm@linux-foundation.org>,
        Christoph Lameter <cl@linux.com>, Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>, linux-kernel@vger.kernel.org,
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Subject: Re: [PATCH] mm/sl[aou]b: make kfree() aware of error pointers
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On Wed, Sep 10, 2014 at 06:53:56PM +0300, Dan Carpenter wrote:
> On Wed, Sep 10, 2014 at 05:28:11PM +0200, Jiri Kosina wrote:
> > 
> > Too late for this now, yes.
> 
> We could still introduce a __kfree_fast_path() which doesn't have
> checking.

Well, there certainly is precedence for that sort of thing.  There is
a bunch of code which uses __brelse(bh) instead of brelse(bh) when the
caller is sure that bh is a valid non-NULL pointer.

						- Ted