Re: [patch 10/10] forcedeth: work around NULL skb dereference crash

[Ingo Molnar]

* Ayaz Abdulla <AAbdulla@xxxxxxxxxx> wrote:

> I had responded eariler to the thread asking you to try out the patch
> found in bug 8058:
> http://bugzilla.kernel.org/show_bug.cgi?id=8058
> 
> I believe that is the caush of the NULL skb dereference issue.

there's a different type of regression now: under high load i dont get a 
crash, i get a hung interface instead. No error packets or other weird 
interface state - just a hung interface. The condition happens after a 
stream of:

 eth1: too many iterations (6) in nv_nic_irq.
 eth1: too many iterations (6) in nv_nic_irq.
 eth1: too many iterations (6) in nv_nic_irq.
 eth1: too many iterations (6) in nv_nic_irq.
 eth1: too many iterations (6) in nv_nic_irq.

If i increase max_interrupt_work from 5 to 50 to paper over this 
condition then the hangs go away. So i suspect there might still be a 
queue-wakeup problem in one of these paths - or that a filled up tx ring 
somehow gets stuck. (and i've got commits 3ba4d093fe8a26f and 
fcc5f2665c81e08, so all the latest stuff that is upstream at the moment)

	Ingo
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/