Fix ixl SR-IOV.

[nyan_myuji.xyz]

Summary

The hw and ifp of a vsi will be NULL if such ixl_vsi is allocated
for a VF. When ixl_reconfigure_filters called, it is trying to
access vsi->ifp and hw->mac.addr and therefore is casuing panic.

This commit add checks to determine if vsi is a VF by checking
if vsi->hw is NULL, before adding IXL_VLAN_ANY filter (which
is already in a VF vsi's filter list) and VLAN filters.

[nyan_myuji.xyz]

Fix typo

[erj]

I think the SR-IOV flows need revisiting (why doesn't the vsi have a valid hw pointer?), but if your fix works, I think we should include it for now to prevent panics.

[krzysztof.galazka_intel.com]

sys/dev/ixl/ixl_pf_main.c

1119

The part about a filter list does not seem correct to me. ixl_init_filters exits early in case of VF VSI. I think it is added later with a virtchnl message. Although as Eric said SR-IOV support needs more attention so getting rid of this panic is a good way to start. Thanks!

[nyan_myuji.xyz]

@erj @krzysztof.galazka_intel.com Thank you so much for reviewing. Do you mind to commit this as well? Thank you so much.

sys/dev/ixl/ixl_pf_main.c

1119

This is very interesting, as when I was tracking done the panic, the vsi->ftl contains exactly 1 filter of IXL_VLAN_ANY, and that lead me to think it was intended.

[erj]

I'm back from vacation; I'll commit it tomorrow if there isn't anything else.