diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index 05df20e47976cb3965c59c5b227e67877bd2d0c4..fb83cdd946436561dbe645f5d742317fea8cfe91 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -197,7 +197,9 @@ MODULE_PARM_DESC(debug, "Bitmapped debugging message enable value");
 
 static void efx_remove_channels(struct efx_nic *efx);
 static void efx_remove_port(struct efx_nic *efx);
+static void efx_init_napi(struct efx_nic *efx);
 static void efx_fini_napi(struct efx_nic *efx);
+static void efx_fini_napi_channel(struct efx_channel *channel);
 static void efx_fini_struct(struct efx_nic *efx);
 static void efx_start_all(struct efx_nic *efx);
 static void efx_stop_all(struct efx_nic *efx);
@@ -335,8 +337,10 @@ void efx_process_channel_now(struct efx_channel *channel)
 
 	/* Disable interrupts and wait for ISRs to complete */
 	efx_nic_disable_interrupts(efx);
-	if (efx->legacy_irq)
+	if (efx->legacy_irq) {
 		synchronize_irq(efx->legacy_irq);
+		efx->legacy_irq_enabled = false;
+	}
 	if (channel->irq)
 		synchronize_irq(channel->irq);
 
@@ -351,6 +355,8 @@ void efx_process_channel_now(struct efx_channel *channel)
 	efx_channel_processed(channel);
 
 	napi_enable(&channel->napi_str);
+	if (efx->legacy_irq)
+		efx->legacy_irq_enabled = true;
 	efx_nic_enable_interrupts(efx);
 }
 
@@ -426,6 +432,7 @@ efx_alloc_channel(struct efx_nic *efx, int i, struct efx_channel *old_channel)
 
 		*channel = *old_channel;
 
+		channel->napi_dev = NULL;
 		memset(&channel->eventq, 0, sizeof(channel->eventq));
 
 		rx_queue = &channel->rx_queue;
@@ -736,9 +743,13 @@ efx_realloc_channels(struct efx_nic *efx, u32 rxq_entries, u32 txq_entries)
 	if (rc)
 		goto rollback;
 
+	efx_init_napi(efx);
+
 	/* Destroy old channels */
-	for (i = 0; i < efx->n_channels; i++)
+	for (i = 0; i < efx->n_channels; i++) {
+		efx_fini_napi_channel(other_channel[i]);
 		efx_remove_channel(other_channel[i]);
+	}
 out:
 	/* Free unused channel structures */
 	for (i = 0; i < efx->n_channels; i++)
@@ -1400,6 +1411,8 @@ static void efx_start_all(struct efx_nic *efx)
 		efx_start_channel(channel);
 	}
 
+	if (efx->legacy_irq)
+		efx->legacy_irq_enabled = true;
 	efx_nic_enable_interrupts(efx);
 
 	/* Switch to event based MCDI completions after enabling interrupts.
@@ -1460,8 +1473,10 @@ static void efx_stop_all(struct efx_nic *efx)
 
 	/* Disable interrupts and wait for ISR to complete */
 	efx_nic_disable_interrupts(efx);
-	if (efx->legacy_irq)
+	if (efx->legacy_irq) {
 		synchronize_irq(efx->legacy_irq);
+		efx->legacy_irq_enabled = false;
+	}
 	efx_for_each_channel(channel, efx) {
 		if (channel->irq)
 			synchronize_irq(channel->irq);
@@ -1593,7 +1608,7 @@ static int efx_ioctl(struct net_device *net_dev, struct ifreq *ifr, int cmd)
  *
  **************************************************************************/
 
-static int efx_init_napi(struct efx_nic *efx)
+static void efx_init_napi(struct efx_nic *efx)
 {
 	struct efx_channel *channel;
 
@@ -1602,18 +1617,21 @@ static int efx_init_napi(struct efx_nic *efx)
 		netif_napi_add(channel->napi_dev, &channel->napi_str,
 			       efx_poll, napi_weight);
 	}
-	return 0;
+}
+
+static void efx_fini_napi_channel(struct efx_channel *channel)
+{
+	if (channel->napi_dev)
+		netif_napi_del(&channel->napi_str);
+	channel->napi_dev = NULL;
 }
 
 static void efx_fini_napi(struct efx_nic *efx)
 {
 	struct efx_channel *channel;
 
-	efx_for_each_channel(channel, efx) {
-		if (channel->napi_dev)
-			netif_napi_del(&channel->napi_str);
-		channel->napi_dev = NULL;
-	}
+	efx_for_each_channel(channel, efx)
+		efx_fini_napi_channel(channel);
 }
 
 /**************************************************************************
@@ -2335,9 +2353,7 @@ static int efx_pci_probe_main(struct efx_nic *efx)
 	if (rc)
 		goto fail1;
 
-	rc = efx_init_napi(efx);
-	if (rc)
-		goto fail2;
+	efx_init_napi(efx);
 
 	rc = efx->type->init(efx);
 	if (rc) {
@@ -2368,7 +2384,6 @@ static int efx_pci_probe_main(struct efx_nic *efx)
 	efx->type->fini(efx);
  fail3:
 	efx_fini_napi(efx);
- fail2:
 	efx_remove_all(efx);
  fail1:
 	return rc;
diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h
index 0a7e26d73b525b13aba1fc9e234d38a699322f2a..b137c889152b14be6486fe9271f00658f81df031 100644
--- a/drivers/net/sfc/net_driver.h
+++ b/drivers/net/sfc/net_driver.h
@@ -621,6 +621,7 @@ struct efx_filter_state;
  * @pci_dev: The PCI device
  * @type: Controller type attributes
  * @legacy_irq: IRQ number
+ * @legacy_irq_enabled: Are IRQs enabled on NIC (INT_EN_KER register)?
  * @workqueue: Workqueue for port reconfigures and the HW monitor.
  *	Work items do not hold and must not acquire RTNL.
  * @workqueue_name: Name of workqueue
@@ -709,6 +710,7 @@ struct efx_nic {
 	struct pci_dev *pci_dev;
 	const struct efx_nic_type *type;
 	int legacy_irq;
+	bool legacy_irq_enabled;
 	struct workqueue_struct *workqueue;
 	char workqueue_name[16];
 	struct work_struct reset_work;
diff --git a/drivers/net/sfc/nic.c b/drivers/net/sfc/nic.c
index 41c36b9a4244b907907936b0a6abeaf8f2a301d1..67cb0c96838caeee1bc0497266ef51dd8e9bb407 100644
--- a/drivers/net/sfc/nic.c
+++ b/drivers/net/sfc/nic.c
@@ -1418,6 +1418,12 @@ static irqreturn_t efx_legacy_interrupt(int irq, void *dev_id)
 	u32 queues;
 	int syserr;
 
+	/* Could this be ours?  If interrupts are disabled then the
+	 * channel state may not be valid.
+	 */
+	if (!efx->legacy_irq_enabled)
+		return result;
+
 	/* Read the ISR which also ACKs the interrupts */
 	efx_readd(efx, &reg, FR_BZ_INT_ISR0);
 	queues = EFX_EXTRACT_DWORD(reg, 0, 31);