Folks,
  I've been doing some hacking around in the kernel
in the ethernet driver, and am getting the following
panic whenever I try to ping with a packet size of 1499
or greater:

panic: trap: type 0xf, code 0x0, v 0x0--no pcb

  This message repeats over and over; the panic switch does
not drop me into the debugger. Eventually the messages stop
and the machine sits there, only a power-cycle is effective
then.

  Ping packets with more than 1472 bytes of data have to be
fragmented into two IP packets on the wire (The IP+ICMP headers
add 28 bytes to a ping, and you can fit 1500 bytes into a single
ethernet frame).
  From the machine being pinged I can see both fragments
arrive for pings with 1498 bytes of data. If I try to ping
with 1499 bytes, the first fragment arrives and then the
NetBSD machine panics with the above message.

  Has anyone else seen this, or can you confirm the panic
occurs on your machine? Unfortunately I cannot revert to the
stock kernel to try it, the ethernet driver doesn't support my
hardware without modifications.

--Denny

PS: The command is "ping -s <size> <destination>". If <size> is
1498 or less it should be fine,. 1499 or more my machine panics.