Date: Mon, 7 Aug 2017 09:37:46 -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
In-Reply-To: <20170804231002.20362-1-labbott@redhat.com>
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References: <20170804231002.20362-1-labbott@redhat.com>
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On Fri, 4 Aug 2017, Laura Abbott wrote:

> All slub debug features currently disable the fast path completely.
> Some features such as consistency checks require this to allow taking of
> locks. Poisoning and red zoning don't require this and can safely use
> the per-cpu fast path. Introduce a Kconfig to continue to use the fast
> path when 'fast' debugging options are enabled. The code will
> automatically revert to always using the slow path when 'slow' options
> are enabled.

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?