From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Miller <davem@davemloft.net>
Subject: Re: [PATCH net-next] arp: flush arp cache on IFF_NOARP change
Date: Mon, 20 May 2013 13:46:33 -0700 (PDT)
Message-ID: <20130520.134633.448574202175922639.davem@davemloft.net>
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=46rom: Timo Ter=E4s <timo.teras@iki.fi>
Date: Mon, 20 May 2013 16:29:01 +0300

> IFF_NOARP affects what kind of neighbor entries are created
> (nud NOARP or nud INCOMPLETE). If the flag changes, flush the arp
> cache to refresh all entries.
>=20
> Signed-off-by: Timo Ter=E4s <timo.teras@iki.fi>
> Cc: Patrick McHardy <kaber@trash.net>

This patch makes no sense at all.

The state bit in ->priv_flags is a boolean stating whether the
notified should do something or not.

But you're setting it to match what IFF_NOARP is.

You should set it any time IFF_NOARP _changes_, and then clear
the bit when the notifier clears the neighbour entries.