From mboxrd@z Thu Jan  1 00:00:00 1970
From: Flavio Leitner <fbl@redhat.com>
Subject: Re: [net-next] bonding: don't allow the master to become its slave
Date: Thu, 9 Aug 2012 16:39:06 -0300
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Cc: netdev <netdev@vger.kernel.org>, Jay Vosburgh <fubar@us.ibm.com>,
	Andy Gospodarek <andy@greyhouse.net>,
	Leonardo Chiquitto <lchiquitto@suse.com>,
	Jiri Pirko <jpirko@redhat.com>
To: Ben Hutchings <bhutchings@solarflare.com>
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On Thu, 9 Aug 2012 20:03:23 +0100
Ben Hutchings <bhutchings@solarflare.com> wrote:

> On Thu, 2012-08-09 at 15:30 -0300, Flavio Leitner wrote:
> > It doesn't make any sense to allow the master to become
> > its slave. That creates a loop of events causing a crash.
> 
> What if there are other intermediate devices, e.g. the slave is a VLAN
> sub-device of the bond?  And doesn't team also have this problem?
> 
> I think a more general check for such loops might be required.

Maybe patching netdev_set_master() to fail in the loop case is
the way to go.  That would work for bonding, team and bridge.

What you think?

fbl