Fri, Mar 02, 2018 at 04:26:25PM CET, alexander.du...@gmail.com wrote: >On Fri, Mar 2, 2018 at 12:36 AM, Jiri Pirko <j...@resnulli.us> wrote: >> Thu, Mar 01, 2018 at 09:08:43PM CET, sridhar.samudr...@intel.com wrote: >>>This patch enables virtio_net 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 enable only one datapath at any time so that >>>packets don't get looped back to the VM over the other datapath. When a VF >>>is plugged, the virtio datapath link state can be marked as down. 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. >>> >>>When BACKUP feature is enabled, an additional netdev(bypass netdev) is >>>created that acts as a master device and tracks the state of the 2 lower >>>netdevs. The original virtio_net netdev is marked as 'backup' netdev and a >>>passthru device with the same MAC is registered as 'active' netdev. >>> >>>This patch is based on the discussion initiated by Jesse on this thread. >>>https://marc.info/?l=linux-virtualization&m=151189725224231&w=2 >>> >>>Signed-off-by: Sridhar Samudrala <sridhar.samudr...@intel.com> >>>Signed-off-by: Alexander Duyck <alexander.h.du...@intel.com> >>>Reviewed-by: Jesse Brandeburg <jesse.brandeb...@intel.com> >>>--- >>> drivers/net/virtio_net.c | 683 >>> ++++++++++++++++++++++++++++++++++++++++++++++- >> >> As I wrote to the discussion of the other version of this patchset, >> I strongly believe you need to have a common part in net/core/ that will >> be shared by both virtio_net and netvsc. There there should be explicit >> limits for this in-driver bonding solution, like max 1 vf slave, etc. > >Yeah, this code essentially calls out the "shareable" code with a >comment at the start and end of the section what defines the >virtio_bypass functionality. It would just be a matter of mostly >cutting and pasting to put it into a separate driver module.
Please put it there and unite the use of it with netvsc. > >The design limits things to a 1:1 relationship since we just have the >child and backup pointers, but I don't think I am seeing exception >handling to prevent us from overwriting the child pointers so there >may be a leak there. Ok.
