idpf: avoid vport access in idpf_get_link_ksettings

When the device control plane is removed or the platform
running device control plane is rebooted, a reset is detected
on the driver. On driver reset, it releases the resources and
waits for the reset to complete. If the reset fails, it takes
the error path and releases the vport lock. At this time if the
monitoring tools tries to access link settings, it call traces
for accessing released vport pointer.

To avoid it, move link_speed_mbps to netdev_priv structure
which removes the dependency on vport pointer and the vport lock
in idpf_get_link_ksettings. Also use netif_carrier_ok()
to check the link status and adjust the offsetof to use link_up
instead of link_speed_mbps.

Fixes: 02cbfba ("idpf: add ethtool callbacks")
Cc: [email protected] # 6.7+
Reviewed-by: Tarun K Singh <[email protected]>
Signed-off-by: Pavan Kumar Linga <[email protected]>
Tested-by: Krishneil Singh <[email protected]>
Signed-off-by: Tony Nguyen <[email protected]>

Author: plinga1

drivers/net/ethernet/intel/idpf/idpf.h

@@ -141,6 +141,7 @@ enum idpf_vport_state {
  * @adapter: Adapter back pointer
  * @vport: Vport back pointer
  * @vport_id: Vport identifier
+ * @link_speed_mbps: Link speed in mbps
  * @vport_idx: Relative vport index
  * @state: See enum idpf_vport_state
  * @netstats: Packet and byte stats
@@ -150,6 +151,7 @@ struct idpf_netdev_priv {
 	struct idpf_adapter *adapter;
 	struct idpf_vport *vport;
 	u32 vport_id;
+	u32 link_speed_mbps;
 	u16 vport_idx;
 	enum idpf_vport_state state;
 	struct rtnl_link_stats64 netstats;
@@ -287,7 +289,6 @@ struct idpf_port_stats {
  * @tx_itr_profile: TX profiles for Dynamic Interrupt Moderation
  * @port_stats: per port csum, header split, and other offload stats
  * @link_up: True if link is up
- * @link_speed_mbps: Link speed in mbps
  * @sw_marker_wq: workqueue for marker packets
  */
 struct idpf_vport {
@@ -331,7 +332,6 @@ struct idpf_vport {
 	struct idpf_port_stats port_stats;
 
 	bool link_up;
-	u32 link_speed_mbps;
 
 	wait_queue_head_t sw_marker_wq;
 };

drivers/net/ethernet/intel/idpf/idpf_ethtool.c

@@ -1296,24 +1296,19 @@ static void idpf_set_msglevel(struct net_device *netdev, u32 data)
 static int idpf_get_link_ksettings(struct net_device *netdev,
 				   struct ethtool_link_ksettings *cmd)
 {
-	struct idpf_vport *vport;
-
-	idpf_vport_ctrl_lock(netdev);
-	vport = idpf_netdev_to_vport(netdev);
+	struct idpf_netdev_priv *np = netdev_priv(netdev);
 
 	ethtool_link_ksettings_zero_link_mode(cmd, supported);
 	cmd->base.autoneg = AUTONEG_DISABLE;
 	cmd->base.port = PORT_NONE;
-	if (vport->link_up) {
+	if (netif_carrier_ok(netdev)) {
 		cmd->base.duplex = DUPLEX_FULL;
-		cmd->base.speed = vport->link_speed_mbps;
+		cmd->base.speed = np->link_speed_mbps;
 	} else {
 		cmd->base.duplex = DUPLEX_UNKNOWN;
 		cmd->base.speed = SPEED_UNKNOWN;
 	}
 
-	idpf_vport_ctrl_unlock(netdev);
-
 	return 0;
 }
 

drivers/net/ethernet/intel/idpf/idpf_lib.c

@@ -1860,7 +1860,7 @@ int idpf_initiate_soft_reset(struct idpf_vport *vport,
 	 * mess with. Nothing below should use those variables from new_vport
 	 * and should instead always refer to them in vport if they need to.
 	 */
-	memcpy(new_vport, vport, offsetof(struct idpf_vport, link_speed_mbps));
+	memcpy(new_vport, vport, offsetof(struct idpf_vport, link_up));
 
 	/* Adjust resource parameters prior to reallocating resources */
 	switch (reset_cause) {
@@ -1906,7 +1906,7 @@ int idpf_initiate_soft_reset(struct idpf_vport *vport,
 	/* Same comment as above regarding avoiding copying the wait_queues and
 	 * mutexes applies here. We do not want to mess with those if possible.
 	 */
-	memcpy(vport, new_vport, offsetof(struct idpf_vport, link_speed_mbps));
+	memcpy(vport, new_vport, offsetof(struct idpf_vport, link_up));
 
 	if (reset_cause == IDPF_SR_Q_CHANGE)
 		idpf_vport_alloc_vec_indexes(vport);

drivers/net/ethernet/intel/idpf/idpf_virtchnl.c

@@ -141,7 +141,7 @@ static void idpf_handle_event_link(struct idpf_adapter *adapter,
 	}
 	np = netdev_priv(vport->netdev);
 
-	vport->link_speed_mbps = le32_to_cpu(v2e->link_speed);
+	np->link_speed_mbps = le32_to_cpu(v2e->link_speed);
 
 	if (vport->link_up == v2e->link_status)
 		return;