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On Fri, 2021-07-09 at 05:33 -0400, Laurent Dumont wrote:
> Hey Rodolfo,
> 
> That was our understanding as well. I guess our thinking is more related to
> if the i40evf driver is present on a compute that is providing a PF/VF to a
> VM, could that create a conflict at some point? 
> 
am in principal it should not as you are menet to be abel to mix usage of the
VFs 

> The VM will use it's own
> Kernel with it's own version of i40evf but the compute providing the SRIOV
> PF is also loaded with i40evf + i40e.
corret the guest will provid its own driver either i40evf or avf most likely unless they are using
dpdk or a similar tech that leverages userspace driver.
> 
> Just looking at understanding the expected deployment scenario.

removal of the i40eVF dirver on the host will have some side effect the main ones being the inablity
to use the VF to provide host networkin and the inablity to use the macvtap vnic_type in neutron.

the macvtap vnic type create a macvtap device ontop of the VF netdev on the host and passes the macvtap to the guest
instead fo the vf allowing the vm to live migrate and not need to have a vendeor driver for the nic at the cost of a perfromance
overhead due to the macvtap device acting as n intermediary.

in general its safe to revmove the dirver on the host but it may also have other implications.
i belive the way we do not rely on the VF having a netdev name for bandwith qos to function just PF but
normally the host has both drifers so this is less well tested.

to prevent the driver being used on the hsot you can add it to the kernel module blacklist
you can do that normally with modprobe.blacklist=driver_name  and rd.driver.blacklist=driver_name
rd.driver.blacklist is for the initram and  modprobe.blacklist is for the running host after the root filesystem is loaded
so you should add i40evf to both.

you can also do it via the file system too https://wiki.archlinux.org/title/Kernel_module#Using_files_in_/etc/modprobe.d/_2



> 
> Thanks!
> 
> On Fri, Jul 9, 2021 at 3:37 AM Rodolfo Alonso Hernandez <ralonsoh at redhat.com>
> wrote:
> 
> > Hello Laurent:
> > 
> > The i40evf is the guest driver when using VFs from a Fortville NIC. The
> > i40e is the host driver that controls the PF and provides the VFs for the
> > guests.
> > 
> > Without the i40evf, the virtual machine cannot use the device provided.
> > 
> > Both drivers have different goals.
> > 
> > Regards.
> > 
> > On Fri, Jul 9, 2021 at 12:58 AM Laurent Dumont <laurentfdumont at gmail.com>
> > wrote:
> > 
> > > Hey everyone,
> > > 
> > > We are troubleshooting some weirdness with X710 Intel cards and i40evf.
> > > Looking around, it seems that most vendors recommend disabling the i40evf
> > > driver from the compute side (and keeping the i40e driver).
> > > 
> > > Is anyone aware of any funkiness if both the i40e driver and the i40evf
> > > driver is present on computes running VMs with SRIOV ports.
> > > 
> > > Thanks!
> > > 
> >