3 files changed, 18 insertions, 2 deletions

diff --git a/drivers/net/sfc/efx.c b/drivers/net/sfc/efx.c
index 05df20e47976..d06cb742164b 100644
--- a/drivers/net/sfc/efx.c
+++ b/drivers/net/sfc/efx.c
@@ -335,8 +335,10 @@ 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 +353,8 @@ 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);
 }
 
@@ -1400,6 +1404,8 @@ 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 +1466,10 @@ 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);
diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h
index 0a7e26d73b52..b137c889152b 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 41c36b9a4244..67cb0c96838c 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);