Subject: Trouble with tlp Ethernet on Virtual PC 6
To: None <port-i386@netbsd.org>
From: Jason Thorpe <thorpej@wasabisystems.com>
List: port-i386
Date: 12/18/2003 09:45:35
--Apple-Mail-56--1026945223
Content-Transfer-Encoding: 7bit
Content-Type: text/plain; charset=US-ASCII; format=flowed

Folks...

I'm running NetBSD inside a Virtual PC (hosted on Mac OS 10.3).  I'm 
using this primarily for testing kernel changes.

I'm having trouble using the emulated Ethernet.  Small packets are 
fine, but whenever I get a full-size TCP segment, I see:

tlp0: discarding oversize frame (len=1522)

This is 4 bytes larger than the 1518 maximum Ethernet frame size.  I'm 
not using VLANs, so I would not expect to see packets this large.

Using tcpdump on the vpc, it seems as though the extra 4 bytes are just 
zeros.

I'm wondering if anyone else has observed this.  I'm considering 
tweaking the driver to check for this condition on a 21041 (which is 
what Virtual PC emulates) and simply truncate the packet to 1518 bytes.

Thanks...

         -- Jason R. Thorpe <thorpej@wasabisystems.com>

--Apple-Mail-56--1026945223
content-type: application/pgp-signature; x-mac-type=70674453;
	name=PGP.sig
content-description: This is a digitally signed message part
content-disposition: inline; filename=PGP.sig
content-transfer-encoding: 7bit

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.3 (Darwin)

iD8DBQE/4ee/OpVKkaBm8XkRAok2AJ9JRpKHX0hLcOIm2Ez0plC2st2ysQCdEC1t
aA9c66Iafm2CgZfwDYQX4Ek=
=ARWX
-----END PGP SIGNATURE-----

--Apple-Mail-56--1026945223--