On Fri, Jul 21, 2000 at 05:47:52PM -0700, Kanoj Sarcar wrote:
> Ralf, while running some tests (the kernel got a BUG()), I keep getting
> eth0: RX overflow. messages. It might be because of the previous BUG(),
> which may be preventing normal operation, but thought I would let you
> know ...
RX overflow mean the receiver ringbuffer did overflow. Being a silly
chip the IOC3 signals this condition by disabling receiver & receiver DMA
and and signaling interrupt. It's no serious problem yet the IOC3
overreacts and requires reinitalization of the chip. And this is where
the trouble starts. Above state can be also be entered if interrupts
are disabled for some time or by heavy traffic, try for example (as root):
ping -l 10000000 origin
A few seconds of flooding like this will reliably blow the IOC3 out of the
socks. The problem I have is that my attempts to reinitialize the chip
were rarely successful for some reason but I'm working on it.
If you hit this problem during normal operation then you may try to
increase the value of RX_BUFFS in ioc3-eth.c. It's 32 by default but
can be increased in x 16 steps upto 512. Large values are probably
a waste of money, though.
Ralf
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