Re: Potential re(4) / netbsd-4 / i386 problem?

[Brad du Plessis <bradd%cat.co.za@localhost>]

On 10/28/2010 9:42 AM, Brad du Plessis wrote:
> Hi,
>
> > I've been seeing panics on a netbsd-4/i386 machine which appears to be
> > related to the reception of oversized frames:
> >
> > re0: discarding oversize frame (len=8813) 
>
> I've narrowed down the problem here to a specific change.
> Basically with netbsd-4 branch I see the failure, but if I revert
> only the file:
>
> ./src/sys/dev/mii/rgephy.c
>
> to netbsd-4-0-1-RELEASE the problem goes away.

A quick update.

My oversize frame problems are greatly reduced by
reverting rgephy.c as above, I have however still seen
1 instance of an oversize frame on a system that was at
the time experiencing very high disk I/O load. The
network device stopped working on this system until the
system was rebooted.

So as I see it there appear to be 2 problems which may or
may not be related:

1. Something in the netbsd-4 branch version of rgephy.c
   causes the system to experience a high number of what
   it thinks are oversize frames (on my hardware, given the
   nature of the network traffic in my test). Reverting this file to
   netbsd-4-0-1-RELEASE cures this.

2. Once the driver does handle an oversize frame, the
   kernel will either panic with what appears to be memory
   corruption or the LAN will stop working.


 Brad