On Mon, Apr 23, 2018 at 12:44:39PM -0700, Siwei Liu wrote: > On Mon, Apr 23, 2018 at 10:56 AM, Michael S. Tsirkin <m...@redhat.com> 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" <m...@redhat.com> 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? > > > > It all seems like a reasonable thing to support in the generic core. > > That's the reason why I chose explicit identifier rather than rely on > MAC address to bind/pair a device. MAC address can change. Even if it > can't, malicious guest user can fake MAC address to skip binding. > > -Siwei
Address should be sampled at device creation to prevent this kind of hack. Not that it buys the malicious user much: if you can poke at MAC addresses you probably already can break networking. > > > > > -- > > MST _______________________________________________ Virtualization mailing list Virtualization@lists.linux-foundation.org https://lists.linuxfoundation.org/mailman/listinfo/virtualization
