From mboxrd@z Thu Jan 1 00:00:00 1970 From: Johannes Berg Subject: Re: [PATCH 4/11] use ether_addr_equal_64bits Date: Tue, 31 Dec 2013 00:13:08 +0100 Message-ID: <1388445188.18164.0.camel@jlt4.sipsolutions.net> References: <1388427307-8691-1-git-send-email-Julia.Lawall@lip6.fr> <1388427307-8691-5-git-send-email-Julia.Lawall@lip6.fr> <1388429761.4410.1.camel@jlt4.sipsolutions.net> <1388438724.4573.2.camel@jlt4.sipsolutions.net> <20131230215701.GA4938@khazad-dum.debian.net> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: Julia Lawall , kernel-janitors-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Emmanuel Grumbach , Intel Linux Wireless , "John W. Linville" , linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, netdev-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Henrique de Moraes Holschuh Return-path: In-Reply-To: <20131230215701.GA4938-ZGHd14iZgfaRjzvQDGKj+xxZW9W5cXbT@public.gmane.org> Sender: linux-wireless-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: netdev.vger.kernel.org On Mon, 2013-12-30 at 19:57 -0200, Henrique de Moraes Holschuh wrote: > On Mon, 30 Dec 2013, Johannes Berg wrote: > > On Mon, 2013-12-30 at 20:58 +0100, Julia Lawall wrote: > > > > Is there any way we could catch (sparse, or some other script?) that > > > > struct reorganising won't break the condition needed ("within a > > > > structure that contains at least two more bytes")? > > > > > > What kind of reorganizing could happen? Do you mean that the programmer > > > might do at some time in the future, or something the compiler might do? > > > > I'm just thinking of a programmer, e.g. changing a struct like this: > > > > struct foo { > > u8 addr[ETH_ALEN]; > > - u16 dummy; > > }; > > > > for example. > > That is easily resolved by: > > struct foo { > u8 addr[ETH_ALEN]; > u16 required_padding; /* do not remove upon pain of death */ > }; That'd be a stupid waste of struct space. If anything, there should be *only* a comment saying that at least two bytes are needed - I'd still prefer an automated check. johannes -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html