From: Jarek Poplawski <jarkao2@gmail.com>
Date: Thu, 24 Dec 2009 05:54:29 +0000 (-0800)
Subject: net/via-rhine: Fix scheduling while atomic bugs
X-Git-Tag: v3.12-rc1~11349^2~169
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=c0d7a0212becebe11ffe6979ee3d6f1c4104568d;p=kernel%2Fkernel-generic.git

net/via-rhine: Fix scheduling while atomic bugs

There are BUGs "scheduling while atomic" triggered by the timer
rhine_tx_timeout(). They are caused by calling napi_disable() (with
msleep()). This patch fixes it by moving most of the timer content to
the workqueue function (similarly to other drivers, like tg3), with
spin_lock() changed to BH version.

Additionally, there is spin_lock_irq() moved in rhine_close() to
exclude napi_disable() etc., also tg3's way.

Reported-by: Andrey Rahmatullin <wrar@altlinux.org>
Tested-by: Andrey Rahmatullin <wrar@altlinux.org>
Signed-off-by: Jarek Poplawski <jarkao2@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
---

diff --git a/drivers/net/via-rhine.c b/drivers/net/via-rhine.c
index 593e01f..611b804 100644
--- a/drivers/net/via-rhine.c
+++ b/drivers/net/via-rhine.c
@@ -102,6 +102,7 @@ static const int multicast_filter_limit = 32;
 #include <linux/ethtool.h>
 #include <linux/crc32.h>
 #include <linux/bitops.h>
+#include <linux/workqueue.h>
 #include <asm/processor.h>	/* Processor type for cache alignment. */
 #include <asm/io.h>
 #include <asm/irq.h>
@@ -389,6 +390,7 @@ struct rhine_private {
 	struct net_device *dev;
 	struct napi_struct napi;
 	spinlock_t lock;
+	struct work_struct reset_task;
 
 	/* Frequently used values: keep some adjacent for cache effect. */
 	u32 quirks;
@@ -407,6 +409,7 @@ struct rhine_private {
 static int  mdio_read(struct net_device *dev, int phy_id, int location);
 static void mdio_write(struct net_device *dev, int phy_id, int location, int value);
 static int  rhine_open(struct net_device *dev);
+static void rhine_reset_task(struct work_struct *work);
 static void rhine_tx_timeout(struct net_device *dev);
 static netdev_tx_t rhine_start_tx(struct sk_buff *skb,
 				  struct net_device *dev);
@@ -775,6 +778,8 @@ static int __devinit rhine_init_one(struct pci_dev *pdev,
 	dev->irq = pdev->irq;
 
 	spin_lock_init(&rp->lock);
+	INIT_WORK(&rp->reset_task, rhine_reset_task);
+
 	rp->mii_if.dev = dev;
 	rp->mii_if.mdio_read = mdio_read;
 	rp->mii_if.mdio_write = mdio_write;
@@ -1179,22 +1184,18 @@ static int rhine_open(struct net_device *dev)
 	return 0;
 }
 
-static void rhine_tx_timeout(struct net_device *dev)
+static void rhine_reset_task(struct work_struct *work)
 {
-	struct rhine_private *rp = netdev_priv(dev);
-	void __iomem *ioaddr = rp->base;
-
-	printk(KERN_WARNING "%s: Transmit timed out, status %4.4x, PHY status "
-	       "%4.4x, resetting...\n",
-	       dev->name, ioread16(ioaddr + IntrStatus),
-	       mdio_read(dev, rp->mii_if.phy_id, MII_BMSR));
+	struct rhine_private *rp = container_of(work, struct rhine_private,
+						reset_task);
+	struct net_device *dev = rp->dev;
 
 	/* protect against concurrent rx interrupts */
 	disable_irq(rp->pdev->irq);
 
 	napi_disable(&rp->napi);
 
-	spin_lock(&rp->lock);
+	spin_lock_bh(&rp->lock);
 
 	/* clear all descriptors */
 	free_tbufs(dev);
@@ -1206,7 +1207,7 @@ static void rhine_tx_timeout(struct net_device *dev)
 	rhine_chip_reset(dev);
 	init_registers(dev);
 
-	spin_unlock(&rp->lock);
+	spin_unlock_bh(&rp->lock);
 	enable_irq(rp->pdev->irq);
 
 	dev->trans_start = jiffies;
@@ -1214,6 +1215,19 @@ static void rhine_tx_timeout(struct net_device *dev)
 	netif_wake_queue(dev);
 }
 
+static void rhine_tx_timeout(struct net_device *dev)
+{
+	struct rhine_private *rp = netdev_priv(dev);
+	void __iomem *ioaddr = rp->base;
+
+	printk(KERN_WARNING "%s: Transmit timed out, status %4.4x, PHY status "
+	       "%4.4x, resetting...\n",
+	       dev->name, ioread16(ioaddr + IntrStatus),
+	       mdio_read(dev, rp->mii_if.phy_id, MII_BMSR));
+
+	schedule_work(&rp->reset_task);
+}
+
 static netdev_tx_t rhine_start_tx(struct sk_buff *skb,
 				  struct net_device *dev)
 {
@@ -1830,10 +1844,11 @@ static int rhine_close(struct net_device *dev)
 	struct rhine_private *rp = netdev_priv(dev);
 	void __iomem *ioaddr = rp->base;
 
-	spin_lock_irq(&rp->lock);
-
-	netif_stop_queue(dev);
 	napi_disable(&rp->napi);
+	cancel_work_sync(&rp->reset_task);
+	netif_stop_queue(dev);
+
+	spin_lock_irq(&rp->lock);
 
 	if (debug > 1)
 		printk(KERN_DEBUG "%s: Shutting down ethercard, "