[net-next 09/16] ice: report link down for VF when PF's queues are not enabled

[Jeff Kirsher <jeffrey.t.kirsher@intel.com>]

From: Lukasz Czapnik <lukasz.czapnik@intel.com>

This is port of a fix from i40e commit 2ad1274fa35a ("i40e: don't
report link up for a VF who hasn't enabled queues")

Older VF drivers do not respond well to receiving a link
up notification before queues are enabled. This can cause their state
machine to think that it is safe to send traffic. This results in a Tx
hang on the VF.

Record whether the PF has actually enabled queues for the VF. When
reporting link status, always report link down if the queues aren't
enabled. In this way, the VF driver will never receive a link up
notification until after its queues are enabled.

Signed-off-by: Lukasz Czapnik <lukasz.czapnik@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
Tested-by: Andrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
---
 drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
index 3ba6613048ef..1ec2a037a369 100644
--- a/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
+++ b/drivers/net/ethernet/intel/ice/ice_virtchnl_pf.c
@@ -129,7 +129,10 @@ static void ice_vc_notify_vf_link_state(struct ice_vf *vf)
 	pfe.event = VIRTCHNL_EVENT_LINK_CHANGE;
 	pfe.severity = PF_EVENT_SEVERITY_INFO;
 
-	if (vf->link_forced)
+	/* Always report link is down if the VF queues aren't enabled */
+	if (!vf->num_qs_ena)
+		ice_set_pfe_link(vf, &pfe, ICE_AQ_LINK_SPEED_UNKNOWN, false);
+	else if (vf->link_forced)
 		ice_set_pfe_link_forced(vf, &pfe, vf->link_up);
 	else
 		ice_set_pfe_link(vf, &pfe, ls->link_speed, ls->link_info &
-- 
2.21.0