Re: [PATCH net] neighbour: fix unaligned access to pneigh_entry

[Eric Dumazet]

On Wed, May 31, 2023 at 8:16 PM Jakub Kicinski <kuba@xxxxxxxxxx> wrote:
>
> On Wed, 31 May 2023 18:42:33 +0800 Qingfang DENG wrote:
> > +#ifdef CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS
> >       u8                      key[];
> > +#else
> > +     u8                      key[] __aligned(4);
> > +#endif
>
> I'd appreciate a second opinion, but to me it's very unlikely we'd save
> any memory even with efficient aligned access here. No reasonably key
> will fit into 3 bytes, right? So we can as well avoid the ifdef and
> make the key[] always aligned. Or preferably, if it doesn't cause
> compilation issues, make the type of the key u32?

Same feeling, we could avoid the CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS ifdef.