Merge branch 'net-macb-fix-two-lock-warnings-when-wol-is-used'

Kevin Hao says:

====================
net: macb: Fix two lock warnings when WOL is used

This patch series addresses two lock warnings that occur when using WOL as a
wakeup source on my AMD ZynqMP board.
====================

Link: https://patch.msgid.link/20260318-macb-irq-v2-0-f1179768ab24@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 23 insertions, 14 deletions

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index c16ac9c76aa3..944aab71795c 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c
@@ -5776,9 +5776,9 @@ static int __maybe_unused macb_suspend(struct device *dev)
 	struct macb_queue *queue;
 	struct in_device *idev;
 	unsigned long flags;
+	u32 tmp, ifa_local;
 	unsigned int q;
 	int err;
-	u32 tmp;
 
 	if (!device_may_wakeup(&bp->dev->dev))
 		phy_exit(bp->phy);
@@ -5787,14 +5787,21 @@ static int __maybe_unused macb_suspend(struct device *dev)
 		return 0;
 
 	if (bp->wol & MACB_WOL_ENABLED) {
-		/* Check for IP address in WOL ARP mode */
-		idev = __in_dev_get_rcu(bp->dev);
-		if (idev)
-			ifa = rcu_dereference(idev->ifa_list);
-		if ((bp->wolopts & WAKE_ARP) && !ifa) {
-			netdev_err(netdev, "IP address not assigned as required by WoL walk ARP\n");
-			return -EOPNOTSUPP;
+		if (bp->wolopts & WAKE_ARP) {
+			/* Check for IP address in WOL ARP mode */
+			rcu_read_lock();
+			idev = __in_dev_get_rcu(bp->dev);
+			if (idev)
+				ifa = rcu_dereference(idev->ifa_list);
+			if (!ifa) {
+				rcu_read_unlock();
+				netdev_err(netdev, "IP address not assigned as required by WoL walk ARP\n");
+				return -EOPNOTSUPP;
+			}
+			ifa_local = be32_to_cpu(ifa->ifa_local);
+			rcu_read_unlock();
 		}
+
 		spin_lock_irqsave(&bp->lock, flags);
 
 		/* Disable Tx and Rx engines before  disabling the queues,
@@ -5833,8 +5840,9 @@ static int __maybe_unused macb_suspend(struct device *dev)
 		if (bp->wolopts & WAKE_ARP) {
 			tmp |= MACB_BIT(ARP);
 			/* write IP address into register */
-			tmp |= MACB_BFEXT(IP, be32_to_cpu(ifa->ifa_local));
+			tmp |= MACB_BFEXT(IP, ifa_local);
 		}
+		spin_unlock_irqrestore(&bp->lock, flags);
 
 		/* Change interrupt handler and
 		 * Enable WoL IRQ on queue 0
@@ -5847,11 +5855,12 @@ static int __maybe_unused macb_suspend(struct device *dev)
 				dev_err(dev,
 					"Unable to request IRQ %d (error %d)\n",
 					bp->queues[0].irq, err);
-				spin_unlock_irqrestore(&bp->lock, flags);
 				return err;
 			}
+			spin_lock_irqsave(&bp->lock, flags);
 			queue_writel(bp->queues, IER, GEM_BIT(WOL));
 			gem_writel(bp, WOL, tmp);
+			spin_unlock_irqrestore(&bp->lock, flags);
 		} else {
 			err = devm_request_irq(dev, bp->queues[0].irq, macb_wol_interrupt,
 					       IRQF_SHARED, netdev->name, bp->queues);
@@ -5859,13 +5868,13 @@ static int __maybe_unused macb_suspend(struct device *dev)
 				dev_err(dev,
 					"Unable to request IRQ %d (error %d)\n",
 					bp->queues[0].irq, err);
-				spin_unlock_irqrestore(&bp->lock, flags);
 				return err;
 			}
+			spin_lock_irqsave(&bp->lock, flags);
 			queue_writel(bp->queues, IER, MACB_BIT(WOL));
 			macb_writel(bp, WOL, tmp);
+			spin_unlock_irqrestore(&bp->lock, flags);
 		}
-		spin_unlock_irqrestore(&bp->lock, flags);
 
 		enable_irq_wake(bp->queues[0].irq);
 	}
@@ -5932,6 +5941,8 @@ static int __maybe_unused macb_resume(struct device *dev)
 		queue_readl(bp->queues, ISR);
 		if (bp->caps & MACB_CAPS_ISR_CLEAR_ON_WRITE)
 			queue_writel(bp->queues, ISR, -1);
+		spin_unlock_irqrestore(&bp->lock, flags);
+
 		/* Replace interrupt handler on queue 0 */
 		devm_free_irq(dev, bp->queues[0].irq, bp->queues);
 		err = devm_request_irq(dev, bp->queues[0].irq, macb_interrupt,
@@ -5940,10 +5951,8 @@ static int __maybe_unused macb_resume(struct device *dev)
 			dev_err(dev,
 				"Unable to request IRQ %d (error %d)\n",
 				bp->queues[0].irq, err);
-			spin_unlock_irqrestore(&bp->lock, flags);
 			return err;
 		}
-		spin_unlock_irqrestore(&bp->lock, flags);
 
 		disable_irq_wake(bp->queues[0].irq);