Persistant random receiving packet drops with wi(4) and IBSS

[Mike Wade]

On Thu, 26 Feb 2004, Mike Wade wrote:

> Greetings,
>
> I'm experiencing a rather perplexing problem with 2 wireless nodes running
> FreeBSD 4.9-STABLE utilizing the wi(4) driver in IBSS mode.  Periodically
> I'm unable to receive packets (transmitting packets is fine) but I'm able
> to see the incoming packets via tcpdump running in promisc mode only.  I'm
> not able to see the incoming packets when it's not in promisc mode.

I've discovered some new facts...  If both nodes are in promisc mode then
the receiving packet drops go away.  However, several input errors show up
via netstat and the performance drops from 4.0 mbit/sec to 0.16 mbit/sec.
Pretty bizarre stuff...

The input errors seems to be coming from if_wi.c:

                if (rx_frame.wi_status & WI_STAT_ERRSTAT) {
                        ifp->if_ierrors++;
                        return;
                }
Any ideas?

---
Mike Wade (mwade at bluehighway.net)
Blue Highway Labs, LLC.