linux-kernel - Re: [PATCH 1/9] mtd: cfi_cmdset

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20170511184945.GJ70297@google.com>
Date:   Thu, 11 May 2017 11:49:45 -0700
From:   Brian Norris <computersforpeace@...il.com>
To:     Julia Lawall <Julia.Lawall@...6.fr>
Cc:     David Woodhouse <dwmw2@...radead.org>, keescook@...omium.org,
        kernel-janitors@...r.kernel.org,
        Boris Brezillon <boris.brezillon@...e-electrons.com>,
        Marek Vasut <marek.vasut@...il.com>,
        Richard Weinberger <richard@....at>,
        Cyrille Pitchen <cyrille.pitchen@...ev4u.fr>,
        linux-mtd@...ts.infradead.org, linux-kernel@...r.kernel.org
Subject: Re: [PATCH 1/9] mtd: cfi_cmdset_0020: Drop unnecessary static

On Thu, May 04, 2017 at 10:10:46PM +0200, Julia Lawall wrote:
> Drop static on a local variable, when the variable is initialized before
> any use on every possible execution path through the function.  The static
> has no benefit, and dropping it reduces the code size.
> 
> The semantic patch that fixes this problem is as follows:
> (http://coccinelle.lip6.fr/)
> 
> // <smpl>
> @bad exists@
> position p;
> identifier x;
> type T;
> @@
> 
> static T x@p;
> ...
> x = <+...x...+>
> 
> @@
> identifier x;
> expression e;
> type T;
> position p != bad.p;
> @@
> 
> -static
>  T x@p;
>  ... when != x
>      when strict
> ?x = e;
> // </smpl>
> 
> The change in code size is indicates by the following output from the size
> command.
> 
> before:
>    text    data     bss     dec     hex filename
>   16671      48      16   16735    415f drivers/mtd/chips/cfi_cmdset_0020.o
> 
> after:
>    text    data     bss     dec     hex filename
>   16639      48       8   16695    4137 drivers/mtd/chips/cfi_cmdset_0020.o
> 
> Signed-off-by: Julia Lawall <Julia.Lawall@...6.fr>

Applied patches 1 and 2 to l2-mtd.git/next, for 4.13.