Re: net: tx timeouts with skge, 8139too, dmfe drivers/NICs

[Jeff Garzik <jeff@garzik.org>]

Marin Mitov wrote:
> Hi all,
> 
> I experience very rare freezes at heavy outbound traffic 
> (sending ~4GB DVD image to another host(s) on the same LAN) 
> using skge driver (NIC on the mobo) as well as (recently tested)
> using rtl8139 or dmfe NICs on the PCI bus. There is a single 
> switch between them (tested with another one just to exclude
> a faulty switch).
> 
> skge <--> Marvell 88E8001 chip
> 8139too <--> Realtek 8136B chip
> dmfe <--> Davicom DM9102 chip
> 
> Symptoms are similar: tx timeouts and no more net activity.
> KDE desktop works, computational programs - work, the machine 
> is usable, but cannot ping, nor can be ping-ed anymore.
> rmmod && modprobe the respective modules repairs the problem.
> Simple surfing/e-mailing from it do not trigger the problem.
> 
> The machine is used as LTSP server for old PCs (as X terminals)
> (mostly outbound traffic) and is not usable as such due to this
> problem.
> 
> The kernel is 2.6.24.2-SMP/x86_32 (PREEMPT or not - NO difference).
> 
> As far as this happens with 3 different NICs/drivers could it be
> a problem in the (common for all of them) networking subsystem?

A TX timeout (like hardware timeouts, in general) is a very generic 
behavior, with many causes.

In general, when you see timeouts with varied hardware and drivers, 
you're almost always dealing with a problem with interrupt delivery, or 
a generic system problem, rather than bugs in the network stack or all 
three drivers.

	Jeff