jnemeth@victoria.tc.ca wrote:

> } I've been working on Solaris, and recently added hardware checksum to
> } hme.  In the course of this, it became known to me that NetBSD's hme
> } driver suffers from a flaw (same as mine) involving hardware checksum
> } (tx side) with tiny packets.  The checksum code is busted for packets
> } less than 64-bytes in length, due to a limitation in the controller.
> 
>      When you say "packets less than 64-bytes in length," what parts of
> the packet are you counting?  Ethernet packets must be a minimum of
> 64-bytes in length including the MAC header and FCS.

There are several NICs (ex(4), re(4) etc.) which support auto
padding short packets but also have a bug on hwcksum against
short packets which require padding.
Manual padding may work around such hw bugs.
---
Izumi Tsutsui