From: Ville Nuorvala <vnuorval@tcs.hut.fi>
I've experienced random lockups witch become almost certain under heavy
loads, like when doing ping6 -f. The culprit seems to be the 3c574_cs
driver, which locks lp->window_lock twice when calling update_stats() from
el3_interrupt().
drivers/net/pcmcia/3c574_cs.c | 15 +++++++++------
1 files changed, 9 insertions(+), 6 deletions(-)
diff -puN drivers/net/pcmcia/3c574_cs.c~3c574_cs-deadlock-fix drivers/net/pcmcia/3c574_cs.c
--- 25/drivers/net/pcmcia/3c574_cs.c~3c574_cs-deadlock-fix 2003-12-14 19:47:54.000000000 -0800
+++ 25-akpm/drivers/net/pcmcia/3c574_cs.c 2003-12-14 19:48:48.000000000 -0800
@@ -1092,8 +1092,12 @@ static struct net_device_stats *el3_get_
{
struct el3_private *lp = (struct el3_private *)dev->priv;
- if (netif_device_present(dev))
+ if (netif_device_present(dev)) {
+ unsigned long flags;
+ spin_lock_irqsave(&lp->window_lock, flags);
update_stats(dev);
+ spin_unlock_irqrestore(&lp->window_lock, flags);
+ }
return &lp->stats;
}
@@ -1105,7 +1109,6 @@ static void update_stats(struct net_devi
{
struct el3_private *lp = (struct el3_private *)dev->priv;
ioaddr_t ioaddr = dev->base_addr;
- unsigned long flags;
u8 rx, tx, up;
DEBUG(2, "%s: updating the statistics.\n", dev->name);
@@ -1113,8 +1116,6 @@ static void update_stats(struct net_devi
if (inw(ioaddr+EL3_STATUS) == 0xffff) /* No card. */
return;
- spin_lock_irqsave(&lp->window_lock, flags);
-
/* Unlike the 3c509 we need not turn off stats updates while reading. */
/* Switch to the stats window, and read everything. */
EL3WINDOW(6);
@@ -1139,7 +1140,6 @@ static void update_stats(struct net_devi
lp->stats.tx_bytes += tx + ((up & 0xf0) << 12);
EL3WINDOW(1);
- spin_unlock_irqrestore(&lp->window_lock, flags);
}
static int el3_rx(struct net_device *dev, int worklimit)
@@ -1281,6 +1281,8 @@ static int el3_close(struct net_device *
DEBUG(2, "%s: shutting down ethercard.\n", dev->name);
if (DEV_OK(link)) {
+ unsigned long flags;
+
/* Turn off statistics ASAP. We update lp->stats below. */
outw(StatsDisable, ioaddr + EL3_CMD);
@@ -1290,8 +1292,9 @@ static int el3_close(struct net_device *
/* Note: Switching to window 0 may disable the IRQ. */
EL3WINDOW(0);
-
+ spin_lock_irqsave(&lp->window_lock, flags);
update_stats(dev);
+ spin_unlock_irqrestore(&lp->window_lock, flags);
}
link->open--;
_