linux-kernel - Re: [PATCH 04/15] tty: Remove now superfluous sentinel element from ctl

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: <2023100252-plod-user-4504@gregkh>
Date:   Mon, 2 Oct 2023 11:02:38 +0200
From:   Greg Kroah-Hartman <gregkh@...uxfoundation.org>
To:     Christophe Leroy <christophe.leroy@...roup.eu>
Cc:     Jiri Slaby <jirislaby@...nel.org>,
        "j.granados@...sung.com" <j.granados@...sung.com>,
        Luis Chamberlain <mcgrof@...nel.org>,
        "willy@...radead.org" <willy@...radead.org>,
        "josh@...htriplett.org" <josh@...htriplett.org>,
        Kees Cook <keescook@...omium.org>,
        Phillip Potter <phil@...lpotter.co.uk>,
        Clemens Ladisch <clemens@...isch.de>,
        Arnd Bergmann <arnd@...db.de>, Juergen Gross <jgross@...e.com>,
        Stefano Stabellini <sstabellini@...nel.org>,
        Oleksandr Tyshchenko <oleksandr_tyshchenko@...m.com>,
        "James E.J. Bottomley" <jejb@...ux.ibm.com>,
        "Martin K. Petersen" <martin.petersen@...cle.com>,
        Doug Gilbert <dgilbert@...erlog.com>,
        Sudip Mukherjee <sudipm.mukherjee@...il.com>,
        Jason Gunthorpe <jgg@...pe.ca>,
        Leon Romanovsky <leon@...nel.org>,
        Corey Minyard <minyard@....org>, Theodore Ts'o <tytso@....edu>,
        "Jason A. Donenfeld" <Jason@...c4.com>,
        David Ahern <dsahern@...nel.org>,
        "David S. Miller" <davem@...emloft.net>,
        Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>,
        Paolo Abeni <pabeni@...hat.com>,
        Robin Holt <robinmholt@...il.com>,
        Steve Wahl <steve.wahl@....com>,
        Russ Weight <russell.h.weight@...el.com>,
        "Rafael J. Wysocki" <rafael@...nel.org>,
        Song Liu <song@...nel.org>,
        "K. Y. Srinivasan" <kys@...rosoft.com>,
        Haiyang Zhang <haiyangz@...rosoft.com>,
        Wei Liu <wei.liu@...nel.org>, Dexuan Cui <decui@...rosoft.com>,
        Jani Nikula <jani.nikula@...ux.intel.com>,
        Joonas Lahtinen <joonas.lahtinen@...ux.intel.com>,
        Rodrigo Vivi <rodrigo.vivi@...el.com>,
        Tvrtko Ursulin <tvrtko.ursulin@...ux.intel.com>,
        David Airlie <airlied@...il.com>,
        Daniel Vetter <daniel@...ll.ch>,
        "linux-hyperv@...r.kernel.org" <linux-hyperv@...r.kernel.org>,
        "linux-scsi@...r.kernel.org" <linux-scsi@...r.kernel.org>,
        "linux-rdma@...r.kernel.org" <linux-rdma@...r.kernel.org>,
        "netdev@...r.kernel.org" <netdev@...r.kernel.org>,
        "intel-gfx@...ts.freedesktop.org" <intel-gfx@...ts.freedesktop.org>,
        "linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>,
        "dri-devel@...ts.freedesktop.org" <dri-devel@...ts.freedesktop.org>,
        "linux-raid@...r.kernel.org" <linux-raid@...r.kernel.org>,
        "linux-serial@...r.kernel.org" <linux-serial@...r.kernel.org>,
        "xen-devel@...ts.xenproject.org" <xen-devel@...ts.xenproject.org>,
        "openipmi-developer@...ts.sourceforge.net" 
        <openipmi-developer@...ts.sourceforge.net>,
        "linuxppc-dev@...ts.ozlabs.org" <linuxppc-dev@...ts.ozlabs.org>
Subject: Re: [PATCH 04/15] tty: Remove now superfluous sentinel element from
 ctl_table array

On Mon, Oct 02, 2023 at 08:47:53AM +0000, Christophe Leroy wrote:
> 
> 
> Le 02/10/2023 à 10:17, Jiri Slaby a écrit :
> > On 28. 09. 23, 15:21, Joel Granados via B4 Relay wrote:
> >> From: Joel Granados <j.granados@...sung.com>
> >>
> >> This commit comes at the tail end of a greater effort to remove the
> >> empty elements at the end of the ctl_table arrays (sentinels) which
> >> will reduce the overall build time size of the kernel and run time
> >> memory bloat by ~64 bytes per sentinel (further information Link :
> >> https://lore.kernel.org/all/ZO5Yx5JFogGi%2FcBo@bombadil.infradead.org/)
> >>
> >> Remove sentinel from tty_table
> >>
> >> Signed-off-by: Joel Granados <j.granados@...sung.com>
> >> ---
> >>   drivers/tty/tty_io.c | 3 +--
> >>   1 file changed, 1 insertion(+), 2 deletions(-)
> >>
> >> diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c
> >> index 8a94e5a43c6d..2f925dc54a20 100644
> >> --- a/drivers/tty/tty_io.c
> >> +++ b/drivers/tty/tty_io.c
> >> @@ -3607,8 +3607,7 @@ static struct ctl_table tty_table[] = {
> >>           .proc_handler    = proc_dointvec,
> >>           .extra1        = SYSCTL_ZERO,
> >>           .extra2        = SYSCTL_ONE,
> >> -    },
> >> -    { }
> >> +    }
> > 
> > Why to remove the comma? One would need to add one when adding a new entry?
> 
> Does it make any difference at all ?
> 
> In one case you have:
> 
> @xxxx
>   		something old,
>   	},
> +	{
> +		something new,
> +	},
>   }
> 
> In the other case you have:
> 
> @xxxx
>   		something old,
> + 	},
> +	{
> +		something new,
>   	}
>   }

Because that way it is obvious you are only touching the "something new"
lines and never have to touch the "something old" ones.

It's just a long-standing tradition in Linux, don't have an extra
character if you don't need it :)

thanks,

greg k-h