From mboxrd@z Thu Jan 1 00:00:00 1970 From: Veaceslav Falico Subject: Re: [net-next,1/3] bonding: fix vlan 0 addition and removal Date: Tue, 6 Aug 2013 10:51:11 +0200 Message-ID: <20130806085111.GL22756@redhat.com> References: <1375709304-16778-2-git-send-email-nikolay@redhat.com> <20130805215126.GB3859@redhat.com> <5200B0C4.2020101@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii; format=flowed Cc: netdev@vger.kernel.org, fubar@us.ibm.com, andy@greyhouse.net, davem@davemloft.net, kaber@trash.net To: Nikolay Aleksandrov Return-path: Received: from mx1.redhat.com ([209.132.183.28]:10365 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753781Ab3HFIwH (ORCPT ); Tue, 6 Aug 2013 04:52:07 -0400 Content-Disposition: inline In-Reply-To: <5200B0C4.2020101@redhat.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, Aug 06, 2013 at 10:16:04AM +0200, Nikolay Aleksandrov wrote: >On 08/05/2013 11:51 PM, Veaceslav Falico wrote: >> On Mon, Aug 05, 2013 at 03:28:22PM +0200, nikolay@redhat.com wrote: >> ...snip... >>> This is fixed by forbidding the addition/removal of vlan 0 through the >>> bond's ndo_vlan_rx_add/kill_vid functions, and adding/removing it only when >>> vlan 0 is in fact being created (or destroyed) on top of a bond interface >>> in the bond's netdev handling function. >> >> Isn't that a bit too intrusive/hacky? I don't think we should treat vlan id >> 0 somehow differently in terms of adding/removing, though I might be >> wrong... >> >I didn't want to touch the vlan code, so I solved the problem entirely in >the bonding, mind you there's still a bug when loading the 8021q module >we'll bump up every slave's vlan 0 refcnt without adding the vlan, and it >won't get bumped down. >In my patch that problem still persists but only when an actual vlan 0 is >being created. I'll look into that, though maybe we'll require another patch to fix it. > >> Maybe we should just fix the bond_vlan_used() function? Something like >> this (I've done only basic testing, can do more thorough if needed), though >> it's also not a really clean fix: >> >Yes, that would be optimal and I agree. > >> From 1c89abefebe90568ed52d2df59fcfdd650bc4696 Mon Sep 17 00:00:00 2001 >> From: Veaceslav Falico >> Date: Mon, 5 Aug 2013 23:29:12 +0200 >> Subject: [PATCH] bonding: add vlan_uses_dev_rcu() and make bond_vlan_used() >> use it >> >> Currently, bond_vlan_used() looks for any vlan, including the pseudo-vlan >> id 0, and always returns true if 8021q is loaded. This creates several bad >> situations - some warnings in __bond_release_one() because it thinks that >> we still have vlans while removing, sending LB packets with vlan id 0 and, >> possibly, other caused by vlan id 0. >> >> Fix it by adding a new call, vlan_uses_dev_rcu(), which is the same as >> vlan_uses_dev(), but uses rcu_dereference() instead of rtnl, and thus we >> can use it in bond_vlan_used() wrapped in rcu_read_lock(). >> >> Also, use the pure vlan_uses_dev() in __bond_release_one() cause the rtnl >> lock is held there. >> >> CC: Jay Vosburgh >> CC: Andy Gospodarek >> CC: Patrick McHardy >> CC: "David S. Miller" >> Signed-off-by: Veaceslav Falico >> --- >I'm okay with this fix, if Dave is also okay with this version then you can >submit it as a patch, I'll re-base my third one later and resubmit. Ok, great, then I'll get some testing with this patch and submit it.