On Tue, Dec 31, 2013 at 1:13 AM, Johannes Berg <johannes@xxxxxxxxxxxxxxxx> wrote: > > 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. > Frankly I am not sure I like the patch. This flow is not a fast path at all. While I don't really care for the waste in iwlwifi (because there isn't), I don't see the real point is make the code more sensitive to changes to earn basically nothing. This flow happens only upon association which means a few times an hour maybe... The only advantage I see here is that people like me who don't always have a chance to read / write much code outside their little tiny boring driver get to know about this kind of things. So, from an educational point of view - this is cool. But education is one thing, and the code is another. -- To unsubscribe from this list: send the line "unsubscribe kernel-janitors" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html