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Date:   Mon, 23 Oct 2023 13:16:55 +0200
From:   Florian Westphal <fw@strlen.de>
To:     Lorenzo Bianconi <lorenzo@kernel.org>
Cc:     Florian Westphal <fw@strlen.de>, netfilter-devel@vger.kernel.org
Subject: Re: [PATCH RFC] netfilter: nf_tables: add flowtable map for xdp
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Message-ID: <20231023111655.GA31012@breakpoint.cc>
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Lorenzo Bianconi <lorenzo@kernel.org> wrote:
> thx for working on this, I tested this patch with the flowtable lookup kfunc
> I am working on (code is available here [0]) and it works properly.

Thanks!

> > 
> > Do we need to support dev-in-multiple flowtables?  I would like to
> > avoid this, this likely means the future "xdp" flag in nftables would
> > be restricted to "inet" family.  Alternative would be to change the key to
> > 'device address plus protocol family', the xdp prog could derive that from the
> > packet data.
> > 
> > Timeout handling.  Should the XDP program even bother to refresh the
> > flowtable timeout?
> 
> I was assuming the flowtable lookup kfunc can take care of it.

I'm worried about stale neigh cache, resp. making sure that it
gets renewed.

> > +struct nf_flowtable *nf_flowtable_by_dev(const struct net_device *dev)
> > +{
> 
> I think this routine needs to be added to some include file (e.g.
> include/net/netfilter/nf_flow_table.h)

Right.