Date: Mon, 17 Apr 2017 10:22:29 -0500 (CDT)
From: Christoph Lameter <cl@linux.com>
To: Michal Hocko <mhocko@kernel.org>
cc: Kees Cook <keescook@chromium.org>,
        Andrew Morton <akpm@linux-foundation.org>,
        Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>, Linux-MM <linux-mm@kvack.org>,
        LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] mm: Add additional consistency check
In-Reply-To: <20170411193948.GA29154@dhcp22.suse.cz>
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On Tue, 11 Apr 2017, Michal Hocko wrote:

> On Tue 11-04-17 13:59:44, Cristopher Lameter wrote:
> > On Tue, 11 Apr 2017, Michal Hocko wrote:
> >
> > > I didn't say anything like that. Hence the proposed patch which still
> > > needs some more thinking and evaluation.
> >
> > This patch does not even affect kfree().
>
> Ehm? Are we even talking about the same thing? The whole discussion was
> to catch invalid pointers to _kfree_ and why BUG* is not the best way to
> handle that.

The patch does not do that. See my review. Invalid points to kfree are
already caught with a bug on. See kfree in mm/slub.c