From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ido Schimmel Subject: Re: [PATCH net-next 01/18] net: skb_scrub_packet(): Scrub offload_fwd_mark Date: Mon, 19 Nov 2018 22:06:25 +0200 Message-ID: <20181119200625.GA24261@splinter> References: <20181119161006.5405-1-idosch@mellanox.com> <20181119161006.5405-2-idosch@mellanox.com> <20181119.110745.12820215456503449.davem@davemloft.net> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: idosch@mellanox.com, netdev@vger.kernel.org, linux-kselftest@vger.kernel.org, shuah@kernel.org, jiri@mellanox.com, petrm@mellanox.com, roopa@cumulusnetworks.com, mlxsw@mellanox.com To: David Miller Return-path: Received: from out4-smtp.messagingengine.com ([66.111.4.28]:47141 "EHLO out4-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1730417AbeKTGbn (ORCPT ); Tue, 20 Nov 2018 01:31:43 -0500 Content-Disposition: inline In-Reply-To: <20181119.110745.12820215456503449.davem@davemloft.net> Sender: netdev-owner@vger.kernel.org List-ID: On Mon, Nov 19, 2018 at 11:07:45AM -0800, David Miller wrote: > From: Ido Schimmel > Date: Mon, 19 Nov 2018 16:11:07 +0000 > > > From: Petr Machata > > > > When a packet is trapped and the corresponding SKB marked as > > already-forwarded, it retains this marking even after it is forwarded > > across veth links into another bridge. There, since it ingresses the > > bridge over veth, which doesn't have offload_fwd_mark, it triggers a > > warning in nbp_switchdev_frame_mark(). > > > > Then nbp_switchdev_allowed_egress() decides not to allow egress from > > this bridge through another veth, because the SKB is already marked, and > > the mark (of 0) of course matches. Thus the packet is incorrectly > > blocked. > > > > Solve by resetting offload_fwd_mark() in skb_scrub_packet(). That > > function is called from tunnels and also from veth, and thus catches the > > cases where traffic is forwarded between bridges and transformed in a > > way that invalidates the marking. > > > > Signed-off-by: Petr Machata > > Suggested-by: Ido Schimmel > > Signed-off-by: Ido Schimmel > > As a bug fix this seems relevant for 'net' instead of 'net-next'. This seemed really obscure/specific to this selftest so I deemed it unnecessary for 'net'. Agree that by the book it is 'net' material, so we'll send it there. Thanks for the feedback