Re: [PATCH nf-next] netfilter: meta: add PRANDOM support

[Florian Westphal <fw@strlen.de>]

Daniel Borkmann <daniel@iogearbox.net> wrote:
> On 02/16/2016 02:19 PM, Florian Westphal wrote:
> >Daniel Borkmann <daniel@iogearbox.net> wrote:
> >>>+	case NFT_META_PRANDOM:
> >>>+		if (!prand_inited) {
> >>>+			prandom_seed_full_state(&nft_prandom_state);
> >>>+			prand_inited = true;
> >>>+		}
> >>
> >>Should this be: prandom_init_once() ?
> >
> >Thought about that but this is slowpath so I considered
> >the use of static key magic a bit overkill....
> >
> >I don't mind, if you think prandom_init_once is prefereable I'll respin.
> 
> You'd have the benefit that the prng init would be race free. nft_meta_get_init()
> could be called in parallel from multiple CPUs, right?

We're serialized by nftables' nfnetlink mutex.

I guess I'll just send a V2 and use prandom_init_once after all.

Thanks!