Re: [PATCH net-next 2/2] i40e: Wait for pending VF reset in VF set callbacks

[Simon Horman]

On Tue, Jun 13, 2023 at 02:16:10PM +0200, Ivan Vecera wrote:
> Commit 028daf80117376 ("i40e: Fix attach VF to VM issue") fixed
> a race between i40e_ndo_set_vf_mac() and i40e_reset_vf() during
> an attachment of VF device to VM. This issue is not related to
> setting MAC address only but also VLAN assignment to particular
> VF because the newer libvirt sets configured MAC address as well
> as an optional VLAN. The same behavior is also for i40e's
> .ndo_set_vf_rate and .ndo_set_vf_spoofchk where the callbacks
> just check if the VF was initialized but not wait for the finish
> of pending reset.
> 
> Reproducer:
> [root@host ~]# virsh attach-interface guest hostdev --managed 0000:02:02.0 --mac 52:54:00:b4:aa:bb
> error: Failed to attach interface
> error: Cannot set interface MAC/vlanid to 52:54:00:b4:aa:bb/0 for ifname enp2s0f0 vf 0: Resource temporarily unavailable
> 
> Fix this issue by using i40e_check_vf_init_timeout() helper to check
> whether a reset of particular VF was finished in i40e's
> .ndo_set_vf_vlan, .ndo_set_vf_rate and .ndo_set_vf_spoofchk callbacks.
> 
> Tested-by: Ma Yuying <yuma@xxxxxxxxxx>
> Signed-off-by: Ivan Vecera <ivecera@xxxxxxxxxx>

Reviewed-by: Simon Horman <simon.horman@xxxxxxxxxxxx>