Re: Kernel Panic when loading XDP on i40e driver

[Piotr Raczynski <piotr.raczynski@intel.com>]

On Wed, Aug 19, 2020 at 11:08:31AM -0300, Rafael Vargas wrote:
> Em sex., 7 de ago. de 2020 às 12:51, Rafael Vargas <vargas@khomp.com> escreveu:
> > [...]
> > Using kernel 5.8 (mainline from kernel.org) and a Lenovo Intel X722
> > controller (using the i40e driver). Loading any XDP program to this
> > driver will immediately crash with a Kernel Panic.
> >[...]
>

Hi Rafael,

> I've tested with the net-next kernel and there is no Kernel Panic
> there, but looks like native XDP support is not working on i40e, as
> iproute2 reports it as xdpgeneric. Is this correct or am I missing
> something in the way I load my programs (libbpf's
> bpf_set_link_xdp_fd)?
>

We're aware of the issue with X722 and have the fix cooking,
in general native mode works on i40e, but you'll see issues
with X722. We'll submit a patch ASAP.

If it's reported as xdpgeneric, are you sure you set
XDP_FLAGS_DRV_MODE flag when calling bpf_set_link_xdp_fd?

> Also the driver that is currently supplied by Intel and the one
> supplied in the kernel sources seems to have diverged...

Out of tree driver does not have AF_XDP in place as of now,
however XDP is supposed to work fine, again, not with X722.