ice: Fix VSIs unable to share unicast MAC

The driver currently does not allow two VSIs in the same PF domain
to have the same unicast MAC address. This is incorrect in the sense
that a policy decision is being made in the driver when it must be
left to the user. This approach was causing issues when rebooting
the system with VFs spawned not being able to change their MAC addresses.
Such errors were present in dmesg:

[ 7921.068237] ice 0000:b6:00.2 ens2f2: Unicast MAC 6a:0d:e4:70:ca:d1 already
exists on this PF. Preventing setting VF 7 unicast MAC address to 6a:0d:e4:70:ca:d1

Fix that by removing this restriction. Doing this also allows
us to remove some additional code that's checking if a unicast MAC
filter already exists.

Fixes: 47ebc7b0 ("ice: Check if unicast MAC exists before setting VF MAC")
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Signed-off-by: Sylwester Dziedziuch <sylwesterx.dziedziuch@intel.com>
Signed-off-by: Mateusz Palczewski <mateusz.palczewski@intel.com>
Signed-off-by: Jedrzej Jagielski <jedrzej.jagielski@intel.com>
Tested-by: Marek Szlosek <marek.szlosek@intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

drivers/net/ethernet/intel/ice/ice_main.c

@@ -4656,6 +4656,8 @@ ice_probe(struct pci_dev *pdev, const struct pci_device_id __always_unused *ent)
 		ice_set_safe_mode_caps(hw);
 	}
 
+	hw->ucast_shared = true;
+
 	err = ice_init_pf(pf);
 	if (err) {
 		dev_err(dev, "ice_init_pf failed: %d\n", err);

drivers/net/ethernet/intel/ice/ice_sriov.c

@@ -1309,39 +1309,6 @@ ice_get_vf_cfg(struct net_device *netdev, int vf_id, struct ifla_vf_info *ivi)
 	return ret;
 }
 
-/**
- * ice_unicast_mac_exists - check if the unicast MAC exists on the PF's switch
- * @pf: PF used to reference the switch's rules
- * @umac: unicast MAC to compare against existing switch rules
- *
- * Return true on the first/any match, else return false
- */
-static bool ice_unicast_mac_exists(struct ice_pf *pf, u8 *umac)
-{
-	struct ice_sw_recipe *mac_recipe_list =
-		&pf->hw.switch_info->recp_list[ICE_SW_LKUP_MAC];
-	struct ice_fltr_mgmt_list_entry *list_itr;
-	struct list_head *rule_head;
-	struct mutex *rule_lock; /* protect MAC filter list access */
-
-	rule_head = &mac_recipe_list->filt_rules;
-	rule_lock = &mac_recipe_list->filt_rule_lock;
-
-	mutex_lock(rule_lock);
-	list_for_each_entry(list_itr, rule_head, list_entry) {
-		u8 *existing_mac = &list_itr->fltr_info.l_data.mac.mac_addr[0];
-
-		if (ether_addr_equal(existing_mac, umac)) {
-			mutex_unlock(rule_lock);
-			return true;
-		}
-	}
-
-	mutex_unlock(rule_lock);
-
-	return false;
-}
-
 /**
  * ice_set_vf_mac
  * @netdev: network interface device structure
@@ -1376,13 +1343,6 @@ int ice_set_vf_mac(struct net_device *netdev, int vf_id, u8 *mac)
 	if (ret)
 		goto out_put_vf;
 
-	if (ice_unicast_mac_exists(pf, mac)) {
-		netdev_err(netdev, "Unicast MAC %pM already exists on this PF. Preventing setting VF %u unicast MAC address to %pM\n",
-			   mac, vf_id, mac);
-		ret = -EINVAL;
-		goto out_put_vf;
-	}
-
 	mutex_lock(&vf->cfg_lock);
 
 	/* VF is notified of its new MAC via the PF's response to the