From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Hemminger Subject: Re: [PATCH v7 net-next 4/4] netvsc: refactor notifier/event handling code to use the failover framework Date: Mon, 23 Apr 2018 22:07:46 -0700 Message-ID: <20180423220746.1971d888@xeon-e3> References: <1524188524-28411-1-git-send-email-sridhar.samudrala@intel.com> <1524188524-28411-5-git-send-email-sridhar.samudrala@intel.com> <20180420082802.6ca37e4c@xeon-e3> <20180420160058.GB2150@nanopsycho.orion> <20180423100406.71b95f74@xeon-e3> <20180423202204-mutt-send-email-mst@kernel.org> <20180423104440.2fe6cfd2@xeon-e3> <20180423205019-mutt-send-email-mst@kernel.org> <20180423182503.353180c9@xeon-e3> <20180424043042-mutt-send-email-mst@kernel.org> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Cc: Siwei Liu , Jiri Pirko , Sridhar Samudrala , David Miller , Netdev , virtualization@lists.linux-foundation.org, virtio-dev@lists.oasis-open.org, "Brandeburg, Jesse" , Alexander Duyck , Jakub Kicinski , Jason Wang To: "Michael S. Tsirkin" Return-path: Received: from mail-pg0-f67.google.com ([74.125.83.67]:39787 "EHLO mail-pg0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755725AbeDXFHt (ORCPT ); Tue, 24 Apr 2018 01:07:49 -0400 Received: by mail-pg0-f67.google.com with SMTP id b9so9964572pgf.6 for ; Mon, 23 Apr 2018 22:07:49 -0700 (PDT) In-Reply-To: <20180424043042-mutt-send-email-mst@kernel.org> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 24 Apr 2018 04:42:22 +0300 "Michael S. Tsirkin" wrote: > On Mon, Apr 23, 2018 at 06:25:03PM -0700, Stephen Hemminger wrote: > > On Mon, 23 Apr 2018 12:44:39 -0700 > > Siwei Liu wrote: > > > > > On Mon, Apr 23, 2018 at 10:56 AM, Michael S. Tsirkin wrote: > > > > On Mon, Apr 23, 2018 at 10:44:40AM -0700, Stephen Hemminger wrote: > > > >> On Mon, 23 Apr 2018 20:24:56 +0300 > > > >> "Michael S. Tsirkin" wrote: > > > >> > > > >> > On Mon, Apr 23, 2018 at 10:04:06AM -0700, Stephen Hemminger wrote: > > > >> > > > > > > > >> > > > >I will NAK patches to change to common code for netvsc especially the > > > >> > > > >three device model. MS worked hard with distro vendors to support transparent > > > >> > > > >mode, ans we really can't have a new model; or do backport. > > > >> > > > > > > > >> > > > >Plus, DPDK is now dependent on existing model. > > > >> > > > > > > >> > > > Sorry, but nobody here cares about dpdk or other similar oddities. > > > >> > > > > > >> > > The network device model is a userspace API, and DPDK is a userspace application. > > > >> > > > > >> > It is userspace but are you sure dpdk is actually poking at netdevs? > > > >> > AFAIK it's normally banging device registers directly. > > > >> > > > > >> > > You can't go breaking userspace even if you don't like the application. > > > >> > > > > >> > Could you please explain how is the proposed patchset breaking > > > >> > userspace? Ignoring DPDK for now, I don't think it changes the userspace > > > >> > API at all. > > > >> > > > > >> > > > >> The DPDK has a device driver vdev_netvsc which scans the Linux network devices > > > >> to look for Linux netvsc device and the paired VF device and setup the > > > >> DPDK environment. This setup creates a DPDK failsafe (bondingish) instance > > > >> and sets up TAP support over the Linux netvsc device as well as the Mellanox > > > >> VF device. > > > >> > > > >> So it depends on existing 2 device model. You can't go to a 3 device model > > > >> or start hiding devices from userspace. > > > > > > > > Okay so how does the existing patch break that? IIUC does not go to > > > > a 3 device model since netvsc calls failover_register directly. > > > > > > > >> Also, I am working on associating netvsc and VF device based on serial number > > > >> rather than MAC address. The serial number is how Windows works now, and it makes > > > >> sense for Linux and Windows to use the same mechanism if possible. > > > > > > > > Maybe we should support same for virtio ... > > > > Which serial do you mean? From vpd? > > > > > > > > I guess you will want to keep supporting MAC for old hypervisors? > > > > The serial number has always been in the hypervisor since original support of SR-IOV > > in WS2008. So no backward compatibility special cases would be needed. > > Is that a serial from real hardware or a hypervisor thing? > > It is a hypervisor thing in the PCI hyperv code and the hyperv Netvsc interface. It might also be in the PCI spec, but the value in Hyper-V is being generated by the host.