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From: Christoph Lameter <cl@linux.com>
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To: Kees Cook <keescook@chromium.org>
cc: Michal Hocko <mhocko@kernel.org>,
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Subject: Re: [PATCH] mm: Add additional consistency check
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On Tue, 11 Apr 2017, Kees Cook wrote:

> It seems that enabling the debug checks comes with a non-trivial
> performance impact. I'd like to see consistency checks by default so
> we can handle intentional heap corruption attacks better. This check
> isn't expensive...

Its in a very hot code and frequently used code path.