cvs commit: src/sys/dev/fxp if_fxp.c

[Robert Watson]

On Thu, 15 May 2003, Kris Kennaway wrote:

> On Thu, May 15, 2003 at 06:13:17PM -0700, Robert Watson wrote:
> > rwatson     2003/05/15 18:13:17 PDT
> > 
> >   FreeBSD src repository
> > 
> >   Modified files:
> >     sys/dev/fxp          if_fxp.c 
> >   Log:
> >   Add a tunable/sysctl "hw.fxp_noflow" which disables flow control support
> >   on if_fxp cards.  When flow control is enabled, if the operating system
> >   doesn't acknowledge the packet buffer filling, the card will begin to
> >   generate ethernet quench packets, but appears to get into a feedback
> >   loop of some sort, hosing local switches.  This is a temporary workaround
> >   for 5.1: the ability to configure flow control should probably be
> >   exposed by some or another management interface on ethernet link layer
> >   devices.
> 
> Yay!  This periodically hosed one of my 4.x boxes until I added a hack
> from Peter to turn it off.  Can this be back-ported at some point? 

I imagine it would be a trivial backport, if no one else gets to it in a
day or two, I can do it this weekend.  It could be the patch would even
apply verbatim to RELENG_4 if the drivers are pretty in sync (which they
may well be).

Robert N M Watson             FreeBSD Core Team, TrustedBSD Projects
robert at fledge.watson.org      Network Associates Laboratories