* William Weston <[email protected]> wrote:
> Fortunately, there were some dumps (all ns83820 tx related) left in
> the logs before the machine locked:
i'm not sure it's related to the lockup - but there is a generic bug in
the driver, which in ns83820_tx_timeout() does:
local_irq_save(flags);
...
CALL do_tx_done()
spin_lock_irq(&dev->tx_lock);
...
spin_unlock_irq(&dev->tx_lock); // [1]
...
local_irq_restore(flags); // [2]
this leads to interrupts being enabled at [1], while the intention was
to enable them at [2]. To solve this bug we can do the tx-locking in
ns83820_tx_timeout(). (local_irq_disable() use in ns83820_tx_timeout()
was probably SMP-unsafe too, but needs a rare race.)
find the patch below - it's also included in the -50-05 -RT tree i just
uploaded. Can you confirm that you dont get the warnings in the -50-05
(and later) -RT kernels?
Ingo
Index: drivers/net/ns83820.c
===================================================================
--- drivers/net/ns83820.c.orig
+++ drivers/net/ns83820.c
@@ -1013,8 +1013,6 @@ static void do_tx_done(struct net_device
struct ns83820 *dev = PRIV(ndev);
u32 cmdsts, tx_done_idx, *desc;
- spin_lock_irq(&dev->tx_lock);
-
dprintk("do_tx_done(%p)\n", ndev);
tx_done_idx = dev->tx_done_idx;
desc = dev->tx_descs + (tx_done_idx * DESC_SIZE);
@@ -1070,7 +1068,6 @@ static void do_tx_done(struct net_device
netif_start_queue(ndev);
netif_wake_queue(ndev);
}
- spin_unlock_irq(&dev->tx_lock);
}
static void ns83820_cleanup_tx(struct ns83820 *dev)
@@ -1371,7 +1368,9 @@ static void ns83820_do_isr(struct net_de
* work has accumulated
*/
if ((ISR_TXDESC | ISR_TXIDLE | ISR_TXOK | ISR_TXERR) & isr) {
+ spin_lock_irq(&dev->tx_lock);
do_tx_done(ndev);
+ spin_unlock_irq(&dev->tx_lock);
/* Disable TxOk if there are no outstanding tx packets.
*/
@@ -1456,7 +1455,7 @@ static void ns83820_tx_timeout(struct ne
u32 tx_done_idx, *desc;
unsigned long flags;
- local_irq_save(flags);
+ spin_lock_irqsave(&dev->tx_lock, flags);
tx_done_idx = dev->tx_done_idx;
desc = dev->tx_descs + (tx_done_idx * DESC_SIZE);
@@ -1483,7 +1482,7 @@ static void ns83820_tx_timeout(struct ne
ndev->name,
tx_done_idx, dev->tx_free_idx, le32_to_cpu(desc[DESC_CMDSTS]));
- local_irq_restore(flags);
+ spin_unlock_irqrestore(&dev->tx_lock, flags);
}
-
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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
