i40e: Fix kernel panic on enable/disable LLDP

[cascardo/linux.git] / drivers / net / ethernet / intel / i40e / i40e_main.c

diff --git a/drivers/net/ethernet/intel/i40e/i40e_main.c b/drivers/net/ethernet/intel/i40e/i40e_main.c
index 81c99e1..d0b3a1b 100644 (file)
--- a/drivers/net/ethernet/intel/i40e/i40e_main.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_main.c
@@ -4554,23 +4554,38 @@ static u8 i40e_get_iscsi_tc_map(struct i40e_pf *pf)
  **/
 static u8 i40e_dcb_get_num_tc(struct i40e_dcbx_config *dcbcfg)
 {
+       int i, tc_unused = 0;
        u8 num_tc = 0;
-       int i;
+       u8 ret = 0;
 
        /* Scan the ETS Config Priority Table to find
         * traffic class enabled for a given priority
-        * and use the traffic class index to get the
-        * number of traffic classes enabled
+        * and create a bitmask of enabled TCs
         */
-       for (i = 0; i < I40E_MAX_USER_PRIORITY; i++) {
-               if (dcbcfg->etscfg.prioritytable[i] > num_tc)
-                       num_tc = dcbcfg->etscfg.prioritytable[i];
-       }
+       for (i = 0; i < I40E_MAX_USER_PRIORITY; i++)
+               num_tc |= BIT(dcbcfg->etscfg.prioritytable[i]);
 
-       /* Traffic class index starts from zero so
-        * increment to return the actual count
+       /* Now scan the bitmask to check for
+        * contiguous TCs starting with TC0
         */
-       return num_tc + 1;
+       for (i = 0; i < I40E_MAX_TRAFFIC_CLASS; i++) {
+               if (num_tc & BIT(i)) {
+                       if (!tc_unused) {
+                               ret++;
+                       } else {
+                               pr_err("Non-contiguous TC - Disabling DCB\n");
+                               return 1;
+                       }
+               } else {
+                       tc_unused = 1;
+               }
+       }
+
+       /* There is always at least TC0 */
+       if (!ret)
+               ret = 1;
+
+       return ret;
 }
 
 /**
@@ -5098,9 +5113,13 @@ static int i40e_init_pf_dcb(struct i40e_pf *pf)
                                       DCB_CAP_DCBX_VER_IEEE;
 
                        pf->flags |= I40E_FLAG_DCB_CAPABLE;
-                       /* Enable DCB tagging only when more than one TC */
+                       /* Enable DCB tagging only when more than one TC
+                        * or explicitly disable if only one TC
+                        */
                        if (i40e_dcb_get_num_tc(&hw->local_dcbx_config) > 1)
                                pf->flags |= I40E_FLAG_DCB_ENABLED;
+                       else
+                               pf->flags &= ~I40E_FLAG_DCB_ENABLED;
                        dev_dbg(&pf->pdev->dev,
                                "DCBX offload is supported for this PF.\n");
                }
@@ -5416,7 +5435,6 @@ int i40e_open(struct net_device *netdev)
        wr32(&pf->hw, I40E_GLLAN_TSOMSK_L, be32_to_cpu(TCP_FLAG_CWR) >> 16);
 
        udp_tunnel_get_rx_info(netdev);
-       i40e_notify_client_of_netdev_open(vsi);
 
        return 0;
 }
@@ -5702,7 +5720,7 @@ static int i40e_handle_lldp_event(struct i40e_pf *pf,
        u8 type;
 
        /* Not DCB capable or capability disabled */
-       if (!(pf->flags & I40E_FLAG_DCB_CAPABLE))
+       if (!(pf->flags & I40E_FLAG_DCB_ENABLED))
                return ret;
 
        /* Ignore if event is not for Nearest Bridge */
@@ -7882,6 +7900,7 @@ static int i40e_init_interrupt_scheme(struct i40e_pf *pf)
 #endif
                                       I40E_FLAG_RSS_ENABLED    |
                                       I40E_FLAG_DCB_CAPABLE    |
+                                      I40E_FLAG_DCB_ENABLED    |
                                       I40E_FLAG_SRIOV_ENABLED  |
                                       I40E_FLAG_FD_SB_ENABLED  |
                                       I40E_FLAG_FD_ATR_ENABLED |
@@ -10488,6 +10507,7 @@ static void i40e_determine_queue_usage(struct i40e_pf *pf)
                               I40E_FLAG_FD_SB_ENABLED  |
                               I40E_FLAG_FD_ATR_ENABLED |
                               I40E_FLAG_DCB_CAPABLE    |
+                              I40E_FLAG_DCB_ENABLED    |
                               I40E_FLAG_SRIOV_ENABLED  |
                               I40E_FLAG_VMDQ_ENABLED);
        } else if (!(pf->flags & (I40E_FLAG_RSS_ENABLED |
@@ -10511,7 +10531,8 @@ static void i40e_determine_queue_usage(struct i40e_pf *pf)
                /* Not enough queues for all TCs */
                if ((pf->flags & I40E_FLAG_DCB_CAPABLE) &&
                    (queues_left < I40E_MAX_TRAFFIC_CLASS)) {
-                       pf->flags &= ~I40E_FLAG_DCB_CAPABLE;
+                       pf->flags &= ~(I40E_FLAG_DCB_CAPABLE |
+                                       I40E_FLAG_DCB_ENABLED);
                        dev_info(&pf->pdev->dev, "not enough queues for DCB. DCB is disabled.\n");
                }
                pf->num_lan_qps = max_t(int, pf->rss_size_max,
@@ -10908,7 +10929,7 @@ static int i40e_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
        err = i40e_init_pf_dcb(pf);
        if (err) {
                dev_info(&pdev->dev, "DCB init failed %d, disabled\n", err);
-               pf->flags &= ~I40E_FLAG_DCB_CAPABLE;
+               pf->flags &= ~(I40E_FLAG_DCB_CAPABLE & I40E_FLAG_DCB_ENABLED);
                /* Continue without DCB enabled */
        }
 #endif /* CONFIG_I40E_DCB */