Index: head/sys/dev/e1000/if_em.c
===================================================================
--- head/sys/dev/e1000/if_em.c
+++ head/sys/dev/e1000/if_em.c
@@ -251,6 +251,7 @@
 static void	em_if_vlan_register(if_ctx_t ctx, u16 vtag);
 static void	em_if_vlan_unregister(if_ctx_t ctx, u16 vtag);
 static void	em_if_watchdog_reset(if_ctx_t ctx);
+static bool	em_if_needs_restart(if_ctx_t ctx, enum iflib_restart_event event);
 
 static void	em_identify_hardware(if_ctx_t ctx);
 static int	em_allocate_pci_resources(if_ctx_t ctx);
@@ -400,6 +401,7 @@
 	DEVMETHOD(ifdi_rx_queue_intr_enable, em_if_rx_queue_intr_enable),
 	DEVMETHOD(ifdi_tx_queue_intr_enable, em_if_tx_queue_intr_enable),
 	DEVMETHOD(ifdi_debug, em_if_debug),
+	DEVMETHOD(ifdi_needs_restart, em_if_needs_restart),
 	DEVMETHOD_END
 };
 
@@ -437,6 +439,7 @@
 	DEVMETHOD(ifdi_rx_queue_intr_enable, igb_if_rx_queue_intr_enable),
 	DEVMETHOD(ifdi_tx_queue_intr_enable, igb_if_tx_queue_intr_enable),
 	DEVMETHOD(ifdi_debug, em_if_debug),
+	DEVMETHOD(ifdi_needs_restart, em_if_needs_restart),
 	DEVMETHOD_END
 };
 
@@ -4035,6 +4038,25 @@
 		    adapter->watchdog_events);
 	default:
 		return (if_get_counter_default(ifp, cnt));
+	}
+}
+
+/* em_if_needs_restart - Tell iflib when the driver needs to be reinitialized
+ * @ctx: iflib context
+ * @event: event code to check
+ *
+ * Defaults to returning true for unknown events.
+ *
+ * @returns true if iflib needs to reinit the interface
+ */
+static bool
+em_if_needs_restart(if_ctx_t ctx __unused, enum iflib_restart_event event)
+{
+	switch (event) {
+	case IFLIB_RESTART_VLAN_CONFIG:
+		return (false);
+	default:
+		return (true);
 	}
 }
 
Index: head/sys/dev/ixgbe/if_ix.c
===================================================================
--- head/sys/dev/ixgbe/if_ix.c
+++ head/sys/dev/ixgbe/if_ix.c
@@ -139,6 +139,7 @@
 static void ixgbe_if_vlan_register(if_ctx_t ctx, u16 vtag);
 static void ixgbe_if_vlan_unregister(if_ctx_t ctx, u16 vtag);
 static int  ixgbe_if_i2c_req(if_ctx_t ctx, struct ifi2creq *req);
+static bool ixgbe_if_needs_restart(if_ctx_t ctx, enum iflib_restart_event event);
 int ixgbe_intr(void *arg);
 
 /************************************************************************
@@ -273,6 +274,7 @@
 	DEVMETHOD(ifdi_vlan_unregister, ixgbe_if_vlan_unregister),
 	DEVMETHOD(ifdi_get_counter, ixgbe_if_get_counter),
 	DEVMETHOD(ifdi_i2c_req, ixgbe_if_i2c_req),
+	DEVMETHOD(ifdi_needs_restart, ixgbe_if_needs_restart),
 #ifdef PCI_IOV
 	DEVMETHOD(ifdi_iov_init, ixgbe_if_iov_init),
 	DEVMETHOD(ifdi_iov_uninit, ixgbe_if_iov_uninit),
@@ -1234,6 +1236,25 @@
 		    req->dev_addr, &req->data[i]);
 	return (0);
 } /* ixgbe_if_i2c_req */
+
+/* ixgbe_if_needs_restart - Tell iflib when the driver needs to be reinitialized
+ * @ctx: iflib context
+ * @event: event code to check
+ *
+ * Defaults to returning true for unknown events.
+ *
+ * @returns true if iflib needs to reinit the interface
+ */
+static bool
+ixgbe_if_needs_restart(if_ctx_t ctx __unused, enum iflib_restart_event event)
+{
+	switch (event) {
+	case IFLIB_RESTART_VLAN_CONFIG:
+		return (false);
+	default:
+		return (true);
+	}
+}
 
 /************************************************************************
  * ixgbe_add_media_types
Index: head/sys/dev/ixgbe/if_ixv.c
===================================================================
--- head/sys/dev/ixgbe/if_ixv.c
+++ head/sys/dev/ixgbe/if_ixv.c
@@ -110,6 +110,7 @@
 static void     ixv_if_unregister_vlan(if_ctx_t, u16);
 
 static uint64_t ixv_if_get_counter(if_ctx_t, ift_counter);
+static bool	ixv_if_needs_restart(if_ctx_t, enum iflib_restart_event);
 
 static void     ixv_save_stats(struct adapter *);
 static void     ixv_init_stats(struct adapter *);
@@ -172,6 +173,7 @@
 	DEVMETHOD(ifdi_vlan_register, ixv_if_register_vlan),
 	DEVMETHOD(ifdi_vlan_unregister, ixv_if_unregister_vlan),
 	DEVMETHOD(ifdi_get_counter, ixv_if_get_counter),
+	DEVMETHOD(ifdi_needs_restart, ixv_if_needs_restart),
 	DEVMETHOD_END
 };
 
@@ -1186,6 +1188,25 @@
 		return (if_get_counter_default(ifp, cnt));
 	}
 } /* ixv_if_get_counter */
+
+/* ixv_if_needs_restart - Tell iflib when the driver needs to be reinitialized
+ * @ctx: iflib context
+ * @event: event code to check
+ *
+ * Defaults to returning true for every event.
+ *
+ * @returns true if iflib needs to reinit the interface
+ */
+static bool
+ixv_if_needs_restart(if_ctx_t ctx __unused, enum iflib_restart_event event)
+{
+	switch (event) {
+	case IFLIB_RESTART_VLAN_CONFIG:
+		/* XXX: This may not need to return true */
+	default:
+		return (true);
+	}
+}
 
 /************************************************************************
  * ixv_initialize_transmit_units - Enable transmit unit.
Index: head/sys/dev/ixl/if_iavf.c
===================================================================
--- head/sys/dev/ixl/if_iavf.c
+++ head/sys/dev/ixl/if_iavf.c
@@ -92,6 +92,7 @@
 static void	 iavf_if_vlan_unregister(if_ctx_t ctx, u16 vtag);
 static uint64_t	 iavf_if_get_counter(if_ctx_t ctx, ift_counter cnt);
 static void	 iavf_if_stop(if_ctx_t ctx);
+static bool	 iavf_if_needs_restart(if_ctx_t ctx, enum iflib_restart_event event);
 
 static int	iavf_allocate_pci_resources(struct iavf_sc *);
 static int	iavf_reset_complete(struct i40e_hw *);
@@ -190,6 +191,7 @@
 	DEVMETHOD(ifdi_vlan_register, iavf_if_vlan_register),
 	DEVMETHOD(ifdi_vlan_unregister, iavf_if_vlan_unregister),
 	DEVMETHOD(ifdi_get_counter, iavf_if_get_counter),
+	DEVMETHOD(ifdi_needs_restart, iavf_if_needs_restart),
 	DEVMETHOD_END
 };
 
@@ -1467,7 +1469,27 @@
 	}
 }
 
- 
+/* iavf_if_needs_restart - Tell iflib when the driver needs to be reinitialized
+ * @ctx: iflib context
+ * @event: event code to check
+ *
+ * Defaults to returning true for every event.
+ *
+ * @returns true if iflib needs to reinit the interface
+ */
+static bool
+iavf_if_needs_restart(if_ctx_t ctx __unused, enum iflib_restart_event event)
+{
+	switch (event) {
+	case IFLIB_RESTART_VLAN_CONFIG:
+		/* This case must return true if VLAN anti-spoof checks are
+		 * enabled by the PF driver for the VF.
+		 */
+	default:
+		return (true);
+	}
+}
+
 static void
 iavf_free_pci_resources(struct iavf_sc *sc)
 {
Index: head/sys/dev/ixl/if_ixl.c
===================================================================
--- head/sys/dev/ixl/if_ixl.c
+++ head/sys/dev/ixl/if_ixl.c
@@ -117,6 +117,7 @@
 static uint64_t	 ixl_if_get_counter(if_ctx_t ctx, ift_counter cnt);
 static int	 ixl_if_i2c_req(if_ctx_t ctx, struct ifi2creq *req);
 static int	 ixl_if_priv_ioctl(if_ctx_t ctx, u_long command, caddr_t data);
+static bool	 ixl_if_needs_restart(if_ctx_t ctx, enum iflib_restart_event event);
 #ifdef PCI_IOV
 static void	 ixl_if_vflr_handle(if_ctx_t ctx);
 #endif
@@ -187,6 +188,7 @@
 	DEVMETHOD(ifdi_get_counter, ixl_if_get_counter),
 	DEVMETHOD(ifdi_i2c_req, ixl_if_i2c_req),
 	DEVMETHOD(ifdi_priv_ioctl, ixl_if_priv_ioctl),
+	DEVMETHOD(ifdi_needs_restart, ixl_if_needs_restart),
 #ifdef PCI_IOV
 	DEVMETHOD(ifdi_iov_init, ixl_if_iov_init),
 	DEVMETHOD(ifdi_iov_uninit, ixl_if_iov_uninit),
@@ -1650,6 +1652,24 @@
 	}
 
 	return (error);
+}
+
+/* ixl_if_needs_restart - Tell iflib when the driver needs to be reinitialized
+ * @ctx: iflib context
+ * @event: event code to check
+ *
+ * Defaults to returning false for every event.
+ *
+ * @returns true if iflib needs to reinit the interface, false otherwise
+ */
+static bool
+ixl_if_needs_restart(if_ctx_t ctx __unused, enum iflib_restart_event event)
+{
+	switch (event) {
+	case IFLIB_RESTART_VLAN_CONFIG:
+	default:
+		return (false);
+	}
 }
 
 static u_int