Date: Mon, 7 Aug 2017 13:03:03 -0500 (CDT)
From: Christopher Lameter <cl@linux.com>
To: Laura Abbott <labbott@redhat.com>
cc: Pekka Enberg <penberg@kernel.org>,
        David Rientjes <rientjes@google.com>,
        Joonsoo Kim <iamjoonsoo.kim@lge.com>,
        Andrew Morton <akpm@linux-foundation.org>, linux-mm@kvack.org,
        linux-kernel@vger.kernel.org, Kees Cook <keescook@chromium.org>,
        Rik van Riel <riel@redhat.com>
Subject: Re: [RFC][PATCH] mm/slub.c: Allow poisoning to use the fast path
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References: <20170804231002.20362-1-labbott@redhat.com> <alpine.DEB.2.20.1708070936400.17268@nuc-kabylake> <559096f0-bf1b-eff1-f0ce-33f53a4df255@redhat.com>
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On Mon, 7 Aug 2017, Laura Abbott wrote:

> > Ok I see that the objects are initialized with poisoning and redzoning but
> > I do not see that there is fastpath code to actually check the values
> > before the object is reinitialized. Is that intentional or am
> > I missing something?
>
> Yes, that's intentional here. I see the validation as a separate more
> expensive feature. I had a crude patch to do some checks for testing
> and I know Daniel Micay had an out of tree patch to do some checks
> as well.

Ok then this patch does nothing? How does this help?