* Ingo Molnar <[EMAIL PROTECTED]> wrote:

> my first quick guess was to extend np->priv locking to the whole of 
> nv_start_xmit/nv_start_xmit_optimized - while that appeared to make 
> the crash a bit less likely, it did not prevent it. So there must be 
> some other, more fundamental problem be left as well. At first glance 
> the SMP locking looks OK, so maybe the ring indices are messed up 
> somehow and we got into a 'ring head bites the tail' scenario?

to be specific, the patch below is what i tried - but it didnt 
completely fix the crash.

        Ingo

---
 drivers/net/forcedeth.c |   15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

Index: linux/drivers/net/forcedeth.c
===================================================================
--- linux.orig/drivers/net/forcedeth.c
+++ linux/drivers/net/forcedeth.c
@@ -1650,9 +1650,10 @@ static int nv_start_xmit(struct sk_buff 
                           ((skb_shinfo(skb)->frags[i].size & 
(NV_TX2_TSO_MAX_SIZE-1)) ? 1 : 0);
        }
 
+       spin_lock_irq(&np->lock);
+
        empty_slots = nv_get_empty_tx_slots(np);
        if (unlikely(empty_slots <= entries)) {
-               spin_lock_irq(&np->lock);
                netif_stop_queue(dev);
                np->tx_stop = 1;
                spin_unlock_irq(&np->lock);
@@ -1718,8 +1719,6 @@ static int nv_start_xmit(struct sk_buff 
                tx_flags_extra = skb->ip_summed == CHECKSUM_PARTIAL ?
                         NV_TX2_CHECKSUM_L3 | NV_TX2_CHECKSUM_L4 : 0;
 
-       spin_lock_irq(&np->lock);
-
        /* set tx flags */
        start_tx->flaglen |= cpu_to_le32(tx_flags | tx_flags_extra);
        np->put_tx.orig = put_tx;
@@ -1766,9 +1765,10 @@ static int nv_start_xmit_optimized(struc
                           ((skb_shinfo(skb)->frags[i].size & 
(NV_TX2_TSO_MAX_SIZE-1)) ? 1 : 0);
        }
 
+       spin_lock_irq(&np->lock);
+
        empty_slots = nv_get_empty_tx_slots(np);
        if (unlikely(empty_slots <= entries)) {
-               spin_lock_irq(&np->lock);
                netif_stop_queue(dev);
                np->tx_stop = 1;
                spin_unlock_irq(&np->lock);
@@ -1846,8 +1846,6 @@ static int nv_start_xmit_optimized(struc
                        start_tx->txvlan = 0;
        }
 
-       spin_lock_irq(&np->lock);
-
        /* set tx flags */
        start_tx->flaglen |= cpu_to_le32(tx_flags | tx_flags_extra);
        np->put_tx.ex = put_tx;
@@ -3484,6 +3482,7 @@ static void nv_do_nic_poll(unsigned long
        struct net_device *dev = (struct net_device *) data;
        struct fe_priv *np = netdev_priv(dev);
        u8 __iomem *base = get_hwbase(dev);
+       unsigned long flags;
        u32 mask = 0;
 
        /*
@@ -3519,7 +3518,7 @@ static void nv_do_nic_poll(unsigned long
                printk(KERN_INFO "forcedeth: MAC in recoverable error state\n");
                if (netif_running(dev)) {
                        netif_tx_lock_bh(dev);
-                       spin_lock(&np->lock);
+                       spin_lock_irqsave(&np->lock, flags);
                        /* stop engines */
                        nv_stop_rx(dev);
                        nv_stop_tx(dev);
@@ -3545,7 +3544,7 @@ static void nv_do_nic_poll(unsigned long
                        /* restart rx engine */
                        nv_start_rx(dev);
                        nv_start_tx(dev);
-                       spin_unlock(&np->lock);
+                       spin_unlock_irqrestore(&np->lock, flags);
                        netif_tx_unlock_bh(dev);
                }
        }
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [EMAIL PROTECTED]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to