From: Jakub Kicinski <kuba@kernel.org>
Date: Fri, 24 Jan 2025 03:18:39 +0000 (-0800)
Subject: eth: niu: fix calling napi_enable() in atomic context
X-Git-Tag: v6.14-rc1~33^2~30^2~2
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=f1d12bc7a596fce1df6a02cab1fdb797cc4d1642;p=thirdparty%2Fkernel%2Flinux.git

eth: niu: fix calling napi_enable() in atomic context

napi_enable() may sleep now, take netdev_lock() before np->lock.

Fixes: 413f0271f396 ("net: protect NAPI enablement with netdev_lock()")
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://lore.kernel.org/dcfd56bc-de32-4b11-9e19-d8bd1543745d@stanley.mountain
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250124031841.1179756-6-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
---

diff --git a/drivers/net/ethernet/sun/niu.c b/drivers/net/ethernet/sun/niu.c
index d7459866d24c1..72177fea1cfb3 100644
--- a/drivers/net/ethernet/sun/niu.c
+++ b/drivers/net/ethernet/sun/niu.c
@@ -6086,7 +6086,7 @@ static void niu_enable_napi(struct niu *np)
 	int i;
 
 	for (i = 0; i < np->num_ldg; i++)
-		napi_enable(&np->ldg[i].napi);
+		napi_enable_locked(&np->ldg[i].napi);
 }
 
 static void niu_disable_napi(struct niu *np)
@@ -6116,7 +6116,9 @@ static int niu_open(struct net_device *dev)
 	if (err)
 		goto out_free_channels;
 
+	netdev_lock(dev);
 	niu_enable_napi(np);
+	netdev_unlock(dev);
 
 	spin_lock_irq(&np->lock);
 
@@ -6521,6 +6523,7 @@ static void niu_reset_task(struct work_struct *work)
 
 	niu_reset_buffers(np);
 
+	netdev_lock(np->dev);
 	spin_lock_irqsave(&np->lock, flags);
 
 	err = niu_init_hw(np);
@@ -6531,6 +6534,7 @@ static void niu_reset_task(struct work_struct *work)
 	}
 
 	spin_unlock_irqrestore(&np->lock, flags);
+	netdev_unlock(np->dev);
 }
 
 static void niu_tx_timeout(struct net_device *dev, unsigned int txqueue)
@@ -6761,7 +6765,9 @@ static int niu_change_mtu(struct net_device *dev, int new_mtu)
 
 	niu_free_channels(np);
 
+	netdev_lock(dev);
 	niu_enable_napi(np);
+	netdev_unlock(dev);
 
 	err = niu_alloc_channels(np);
 	if (err)
@@ -9937,6 +9943,7 @@ static int __maybe_unused niu_resume(struct device *dev_d)
 
 	spin_lock_irqsave(&np->lock, flags);
 
+	netdev_lock(dev);
 	err = niu_init_hw(np);
 	if (!err) {
 		np->timer.expires = jiffies + HZ;
@@ -9945,6 +9952,7 @@ static int __maybe_unused niu_resume(struct device *dev_d)
 	}
 
 	spin_unlock_irqrestore(&np->lock, flags);
+	netdev_unlock(dev);
 
 	return err;
 }