Index: sys/dev/igc/if_igc.c
===================================================================
--- sys/dev/igc/if_igc.c
+++ sys/dev/igc/if_igc.c
@@ -117,6 +117,11 @@
 static void	igc_update_stats_counters(struct igc_adapter *);
 static void	igc_add_hw_stats(struct igc_adapter *adapter);
 static int	igc_if_set_promisc(if_ctx_t ctx, int flags);
+static bool	igc_if_vlan_filter_capable(struct igc_adapter *);
+static bool	igc_if_vlan_filter_used(struct igc_adapter *);
+static void	igc_if_vlan_filter_enable(struct igc_adapter *);
+static void	igc_if_vlan_filter_disable(struct igc_adapter *);
+static void	igc_if_vlan_filter_write(struct igc_adapter *);
 static void	igc_setup_vlan_hw_support(struct igc_adapter *);
 static int	igc_sysctl_nvm_info(SYSCTL_HANDLER_ARGS);
 static void	igc_print_nvm_info(struct igc_adapter *);
@@ -844,18 +849,8 @@
 	adapter->rx_mbuf_sz = iflib_get_rx_mbuf_sz(ctx);
 	igc_initialize_receive_unit(ctx);
 
-	/* Use real VLAN Filter support? */
-	if (if_getcapenable(ifp) & IFCAP_VLAN_HWTAGGING) {
-		if (if_getcapenable(ifp) & IFCAP_VLAN_HWFILTER)
-			/* Use real VLAN Filter support */
-			igc_setup_vlan_hw_support(adapter);
-		else {
-			u32 ctrl;
-			ctrl = IGC_READ_REG(&adapter->hw, IGC_CTRL);
-			ctrl |= IGC_CTRL_VME;
-			IGC_WRITE_REG(&adapter->hw, IGC_CTRL, ctrl);
-		}
-	}
+	/* Set up VLAN support and filter */
+	igc_setup_vlan_hw_support(adapter);
 
 	/* Don't lose promiscuous settings */
 	igc_if_set_promisc(ctx, IFF_PROMISC);
@@ -1112,14 +1107,19 @@
 
 	if (flags & IFF_PROMISC) {
 		reg_rctl |= (IGC_RCTL_UPE | IGC_RCTL_MPE);
+		igc_if_vlan_filter_disable(adapter);
 		/* Turn this on if you want to see bad packets */
 		if (igc_debug_sbp)
 			reg_rctl |= IGC_RCTL_SBP;
 		IGC_WRITE_REG(&adapter->hw, IGC_RCTL, reg_rctl);
-	} else if (flags & IFF_ALLMULTI) {
-		reg_rctl |= IGC_RCTL_MPE;
-		reg_rctl &= ~IGC_RCTL_UPE;
-		IGC_WRITE_REG(&adapter->hw, IGC_RCTL, reg_rctl);
+	} else {
+		if (flags & IFF_ALLMULTI) {
+			reg_rctl |= IGC_RCTL_MPE;
+			reg_rctl &= ~IGC_RCTL_UPE;
+			IGC_WRITE_REG(&adapter->hw, IGC_RCTL, reg_rctl);
+		}
+		if (igc_if_vlan_filter_used(adapter))
+			igc_if_vlan_filter_enable(adapter);
 	}
 	return (0);
 }
@@ -2147,6 +2147,7 @@
 	bit = vtag & 0x1F;
 	adapter->shadow_vfta[index] |= (1 << bit);
 	++adapter->num_vlans;
+	igc_if_vlan_filter_write(adapter);
 }
 
 static void
@@ -2159,41 +2160,100 @@
 	bit = vtag & 0x1F;
 	adapter->shadow_vfta[index] &= ~(1 << bit);
 	--adapter->num_vlans;
+	igc_if_vlan_filter_write(adapter);
+}
+
+static bool
+igc_if_vlan_filter_capable(struct igc_adapter *adapter)
+{
+	if_softc_ctx_t scctx = adapter->shared;
+
+	if ((scctx->isc_capenable & IFCAP_VLAN_HWFILTER) &&
+	    !igc_disable_crc_stripping)
+		return (true);
+
+	return (false);
+}
+
+static bool
+igc_if_vlan_filter_used(struct igc_adapter *adapter)
+{
+	if (!igc_if_vlan_filter_capable(adapter))
+		return (false);
+
+	for (int i = 0; i < IGC_VFTA_SIZE; i++)
+		if (adapter->shadow_vfta[i] != 0)
+			return (true);
+
+	return (false);
+}
+
+static void
+igc_if_vlan_filter_enable(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 reg;
+
+	reg = IGC_READ_REG(hw, IGC_RCTL);
+	reg &= ~IGC_RCTL_CFIEN;
+	reg |= IGC_RCTL_VFE;
+	IGC_WRITE_REG(hw, IGC_RCTL, reg);
+}
+
+static void
+igc_if_vlan_filter_disable(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+	u32 reg;
+
+	reg = IGC_READ_REG(hw, IGC_RCTL);
+	reg &= ~(IGC_RCTL_VFE | IGC_RCTL_CFIEN);
+	IGC_WRITE_REG(hw, IGC_RCTL, reg);
+}
+
+static void
+igc_if_vlan_filter_write(struct igc_adapter *adapter)
+{
+	struct igc_hw *hw = &adapter->hw;
+
+	for (int i = 0; i < IGC_VFTA_SIZE; i++)
+		if (adapter->shadow_vfta[i] != 0) {
+			igc_write_vfta(hw, i, adapter->shadow_vfta[i]);
+		}
 }
 
 static void
 igc_setup_vlan_hw_support(struct igc_adapter *adapter)
 {
+	if_softc_ctx_t scctx = adapter->shared;
 	struct igc_hw *hw = &adapter->hw;
 	u32 reg;
 
-	/*
-	 * We get here thru init_locked, meaning
-	 * a soft reset, this has already cleared
-	 * the VFTA and other state, so if there
-	 * have been no vlan's registered do nothing.
-	 */
-	if (adapter->num_vlans == 0)
+	if (scctx->isc_capenable & IFCAP_VLAN_HWTAGGING &&
+	    !igc_disable_crc_stripping) {
+		reg = IGC_READ_REG(hw, IGC_CTRL);
+		reg |= IGC_CTRL_VME;
+		IGC_WRITE_REG(hw, IGC_CTRL, reg);
+	} else {
+		reg = IGC_READ_REG(hw, IGC_CTRL);
+		reg &= ~IGC_CTRL_VME;
+		IGC_WRITE_REG(hw, IGC_CTRL, reg);
+	}
+
+	/* If we aren't doing HW filtering, we're done */
+	if (!igc_if_vlan_filter_capable(adapter))  {
+		igc_if_vlan_filter_disable(adapter);
 		return;
+	}
 
 	/*
 	 * A soft reset zero's out the VFTA, so
 	 * we need to repopulate it now.
 	 */
-	for (int i = 0; i < IGC_VFTA_SIZE; i++)
-		if (adapter->shadow_vfta[i] != 0)
-			IGC_WRITE_REG_ARRAY(hw, IGC_VFTA,
-			    i, adapter->shadow_vfta[i]);
-
-	reg = IGC_READ_REG(hw, IGC_CTRL);
-	reg |= IGC_CTRL_VME;
-	IGC_WRITE_REG(hw, IGC_CTRL, reg);
+	igc_if_vlan_filter_write(adapter);
 
 	/* Enable the Filter Table */
-	reg = IGC_READ_REG(hw, IGC_RCTL);
-	reg &= ~IGC_RCTL_CFIEN;
-	reg |= IGC_RCTL_VFE;
-	IGC_WRITE_REG(hw, IGC_RCTL, reg);
+	igc_if_vlan_filter_enable(adapter);
 }
 
 static void
@@ -2469,6 +2529,7 @@
 {
 	switch (event) {
 	case IFLIB_RESTART_VLAN_CONFIG:
+		return (false);
 	default:
 		return (true);
 	}