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Date: Thu, 2 May 2024 08:10:32 -0700
From: Kees Cook <keescook@chromium.org>
To: Andy Shevchenko <andy.shevchenko@gmail.com>
Cc: "Hsin-Yu.Chen" <harry021633@gmail.com>, andy@kernel.org,
	akpm@linux-foundation.org, linux-hardening@vger.kernel.org,
	linux-kernel@vger.kernel.org
Subject: Re: [PATCH 2/2] string: improve strlen performance
Message-ID: <202405020809.C8973634BF@keescook>
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On Thu, May 02, 2024 at 06:03:04PM +0300, Andy Shevchenko wrote:
> On Thu, May 2, 2024 at 5:59 PM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> > On Thu, May 2, 2024 at 5:14 PM Hsin-Yu.Chen <harry021633@gmail.com> wrote:
> 
> And on top of that, check what this code will do on the architectures
> that do not support unaligned access. If everything is fine, mention
> this in the commit message. Btw, your commit message needs
> elaboration, e.g., pointing to the test case (which is absent in this
> patch, I assume it's already in the kernel?) and step-by-step
> instructions on how you got the mentioned results with details of the
> hardware you used for that.

I might be worth looking at the implementation of strscpy(), which is
doing similar multi-byte steps and handles unaligned access.

-- 
Kees Cook