From mboxrd@z Thu Jan  1 00:00:00 1970
From: Alexei Starovoitov <alexei.starovoitov@gmail.com>
Subject: Re: [PATCH net] net: try harder to not reuse ifindex when moving
 interfaces
Date: Mon, 19 Oct 2015 08:36:10 -0700
Message-ID: <20151019153609.GA19724@Alexeis-MBP.westell.com>
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Cc: netdev@vger.kernel.org, Thomas Haller <thaller@redhat.com>
To: Jiri Benc <jbenc@redhat.com>
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On Mon, Oct 19, 2015 at 11:06:49AM +0200, Jiri Benc wrote:
> On Sun, 18 Oct 2015 08:11:58 -0700, Alexei Starovoitov wrote:
> > it looks dangerous.
> > Does it mean that 'for (4B) { create new dev; free old dev; }
> > will keep incrementing that max index and dos it eventually?
> 
> This is not changed by this patch in any way. As for the current
> behavior (with or without my patch), by creating and deleting an
> interface, the max index indeed keeps incrementing. There's no DoS,
> however, as the index simply wraps to 1 when reaching maxint. See
> dev_new_index(). This is something I count on in this patch.

makes sense. thanks for explaining.