From mboxrd@z Thu Jan  1 00:00:00 1970
From: Andrew Lunn <andrew@lunn.ch>
Subject: Re: [PATCH RFC net-next] net: SAIL based FIB lookup for XDP
Date: Sun, 18 Nov 2018 18:52:53 +0100
Message-ID: <20181118175253.GB7446@lunn.ch>
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Cc: "Md. Islam" <mislam4@kent.edu>, Netdev <netdev@vger.kernel.org>,
        Jesper Dangaard Brouer <brouer@redhat.com>,
        David Miller <davem@davemloft.net>,
        Stephen Hemminger <stephen@networkplumber.org>,
        john fastabend <john.fastabend@gmail.com>,
        Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
To: David Ahern <dsahern@gmail.com>
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> > + * The router can have upto 255 ports. This limitation
> > + * allows us to represent netdev_index as an u8
> > + */
> > +#define NETDEV_COUNT_MAX 255
> 
> ... 255 is high for a physical port count but not a logical device
> count. In the presence of VLANs 255 is nothing and VLANs are an
> essential deployment feature.

I agree with David here. Doing some network simulation work using
namespaces, i've had more than 255 devices in the root namespace.

	    Andrew