From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jakub Kicinski Subject: Re: [PATCH net-next 0/2] Enable virtio to act as a master for a passthru device Date: Tue, 2 Jan 2018 18:16:03 -0800 Message-ID: <20180102181603.7fe4fd1e@cakuba.netronome.com> References: <1514939738-22423-1-git-send-email-sridhar.samudrala@intel.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Sridhar Samudrala , mst@redhat.com, stephen@networkplumber.org, netdev@vger.kernel.org, virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org, Alexander Duyck To: jesse.brandeburg@intel.com Return-path: Received: from mx3.wp.pl ([212.77.101.10]:52866 "EHLO mx3.wp.pl" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750996AbeACCQL (ORCPT ); Tue, 2 Jan 2018 21:16:11 -0500 In-Reply-To: <1514939738-22423-1-git-send-email-sridhar.samudrala@intel.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2 Jan 2018 16:35:36 -0800, Sridhar Samudrala wrote: > This patch series enables virtio to switch over to a VF datapath when a VF > netdev is present with the same MAC address. It allows live migration of a VM > with a direct attached VF without the need to setup a bond/team between a > VF and virtio net device in the guest. > > The hypervisor needs to unplug the VF device from the guest on the source > host and reset the MAC filter of the VF to initiate failover of datapath to > virtio before starting the migration. After the migration is completed, the > destination hypervisor sets the MAC filter on the VF and plugs it back to > the guest to switch over to VF datapath. > > It is based on netvsc implementation and it may be possible to make this code > generic and move it to a common location that can be shared by netvsc and virtio. > > This patch series is based on the discussion initiated by Jesse on this thread. > https://marc.info/?l=linux-virtualization&m=151189725224231&w=2 How does the notion of a device which is both a bond and a leg of a bond fit with Alex's recent discussions about feature propagation? Which propagation rules will apply to VirtIO master? Meaning of the flags on a software upper device may be different. Why muddy the architecture like this and not introduce a synthetic bond device?