From mboxrd@z Thu Jan 1 00:00:00 1970 From: David Miller Subject: Re: active-backup/bonding with drivers not supporting set_mac_address() Date: Mon, 10 Jul 2006 11:23:22 -0700 (PDT) Message-ID: <20060710.112322.100334803.davem@davemloft.net> References: Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org Return-path: Received: from dsl027-180-168.sfo1.dsl.speakeasy.net ([216.27.180.168]:19397 "EHLO sunset.davemloft.net") by vger.kernel.org with ESMTP id S1422745AbWGJSWj (ORCPT ); Mon, 10 Jul 2006 14:22:39 -0400 To: ogerlitz@voltaire.com In-Reply-To: Sender: netdev-owner@vger.kernel.org List-Id: netdev.vger.kernel.org From: Or Gerlitz Date: Mon, 10 Jul 2006 16:43:36 +0300 (IDT) > Looking on the linux bonding driver, it seems to unconditionally (*) > assume that the enslaved device supports the set_mac_address call. > > >From reading the doc (Documentation/networking/bonding.txt) i understand that > it is **not** a must prerequisite for the active-backup mode, this is since > there is at most one active slave at each point of time and as the doc states: > > when a failover occurs in active-backup mode, bonding will issue > one or more gratuitous ARPs on the newly active slave. > > I'd like to get feedback from people here if you think it makes sense > to change the bonding driver to actually allow for active-backup/bonding > with network device drivers which does not support set_mac_address. Blindly dereferencing the ->set_mac_address method is wrong, it does seem. Regardless of whether we add support for active-backup/bonding for devices without this method, in the mean time the bonding driver should check for whether that method is NULL and disallow the bond configuration if it is.