lkml.org 
[lkml]   [2009]   [Dec]   [22]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
Date
From
Subject[PATCH] net/via-rhine: Fix scheduling while atomic bugs
On Tue, Dec 22, 2009 at 04:26:59PM +0100, Roger Luethi wrote:
> On Tue, 22 Dec 2009 20:00:45 +0500, Andrey Rahmatullin wrote:
> > On Tue, Dec 22, 2009 at 01:38:17PM +0000, Jarek Poplawski wrote:
> > > > > It looks like napi_disable() should be illegal in ndo_tx_timeout().
> > > > > Here is a patch which moves most of the timeout work to a workqueue,
> > > > > similarly to tg3 etc. It should prevent at least one of reported
> > > > > bugs. Alas I can't even check-compile it at the moment, so let me
> > > > > know on any problems.
> > > > It seems I needlessly changed locking btw, so here it is again.
> > > Hmm... On the other hand, it definitely needs at least _bh now...
> > I've tried this patch. There are lots of "Transmit timed out", but no
> > crashes.
>
> ACK. Looks like you guys tracked down the crashing and fixed it (thanks!).
> I suspect we shouldn't have to reset due to timeouts that often, but that's
> another story.
>
> Roger

Thanks everybody,
Jarek P.
------------------->

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>
Cc: Christian Kujau <lists@nerdbynature.de>
Cc: Roger Luethi <rl@hellgate.ch>
---

drivers/net/via-rhine.c | 41 ++++++++++++++++++++++++++++-------------
1 files changed, 28 insertions(+), 13 deletions(-)

diff --git a/drivers/net/via-rhine.c b/drivers/net/via-rhine.c
index 593e01f..125406b 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, "



\
 
 \ /
  Last update: 2009-12-22 18:39    [W:0.098 / U:0.328 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site