[PATCH v4.9 -stable] sfc: provide dummy definitions of vswitch functions

[Bert Kenward]

efx_probe_all() calls efx->type->vswitching_probe during probe. For
SFC4000 (Falcon) NICs this function is not defined, leading to a BUG
with the top of the call stack similar to:
  ? efx_pci_probe_main+0x29a/0x830
  efx_pci_probe+0x7d3/0xe70

vswitching_restore and vswitching_remove also need to be defined.

Fixed in mainline by:
commit 5a6681e22c14 ("sfc: separate out SFC4000 ("Falcon") support into new 
sfc-falcon driver")

Fixes: 6d8aaaf6f798 ("sfc: create VEB vswitch and vport above default firmware 
setup")
Signed-off-by: Bert Kenward <bkenw...@solarflare.com>
---
 drivers/net/ethernet/sfc/falcon.c | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/drivers/net/ethernet/sfc/falcon.c 
b/drivers/net/ethernet/sfc/falcon.c
index 1a7092602aec..1bfb21465ace 100644
--- a/drivers/net/ethernet/sfc/falcon.c
+++ b/drivers/net/ethernet/sfc/falcon.c
@@ -2801,6 +2801,11 @@ const struct efx_nic_type falcon_a1_nic_type = {
        .timer_period_max =  1 << FRF_AB_TC_TIMER_VAL_WIDTH,
        .offload_features = NETIF_F_IP_CSUM,
        .mcdi_max_ver = -1,
+#ifdef CONFIG_SFC_SRIOV
+       .vswitching_probe = efx_port_dummy_op_int,
+       .vswitching_restore = efx_port_dummy_op_int,
+       .vswitching_remove = efx_port_dummy_op_void,
+#endif
 };
 
 const struct efx_nic_type falcon_b0_nic_type = {
@@ -2902,4 +2907,9 @@ const struct efx_nic_type falcon_b0_nic_type = {
        .offload_features = NETIF_F_IP_CSUM | NETIF_F_RXHASH | NETIF_F_NTUPLE,
        .mcdi_max_ver = -1,
        .max_rx_ip_filters = FR_BZ_RX_FILTER_TBL0_ROWS,
+#ifdef CONFIG_SFC_SRIOV
+       .vswitching_probe = efx_port_dummy_op_int,
+       .vswitching_restore = efx_port_dummy_op_int,
+       .vswitching_remove = efx_port_dummy_op_void,
+#endif
 };
-- 
2.7.5