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From:   Song Liu <song@kernel.org>
Date:   Thu, 7 Dec 2023 21:33:17 -0800
Message-ID: <CAPhsuW43g-M+xvzD0N1JsJ_zGnvZQOw2Bi1TEqoHKanPnvMHLQ@mail.gmail.com>
Subject: Re: [PATCH] md/md-multipath: Convert "struct mpconf" to flexible array
To:     Kees Cook <keescook@chromium.org>
Cc:     Christophe JAILLET <christophe.jaillet@wanadoo.fr>,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        linux-kernel@vger.kernel.org, kernel-janitors@vger.kernel.org,
        linux-raid@vger.kernel.org, linux-hardening@vger.kernel.org
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On Mon, Dec 4, 2023 at 2:20=E2=80=AFPM Kees Cook <keescook@chromium.org> wr=
ote:
>
> On Sun, Dec 03, 2023 at 08:48:06PM +0100, Christophe JAILLET wrote:
> > The 'multipaths' field of 'struct mpconf' can be declared as a flexible
> > array.
> >
> > The advantages are:
> >    - 1 less indirection when accessing to the 'multipaths' array
> >    - save 1 pointer in the structure
> >    - improve memory usage
> >    - give the opportunity to use __counted_by() for additional safety
> >
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
>
> This looks like a really nice conversion. I haven't run-tested this, but
> it reads correct to me.

Agreed this is a good optimization. However, since MD_MULTIPATH is
already marked as deprecated. I don't think we should ship further
changes to it.

Thanks,
Song