sis(4) flow control

Christian Weisgerber naddy at
Wed Jul 17 12:01:44 UTC 2013

Yonghyeon PYUN <pyunyh at> wrote:

> msk(4) supported flow-control from day 1 with a hack and it was
> re-implemented later with proper way such that it always announces
> flow-control. However for other drivers(i.e vr(4)) that didn't
> support the feature in the beginning, you have to explicitly enable
> the feature. The decision was made to provide compatibility and to
> not introduce POLA.

Funny how POLA is different for different people.  I'm completely
surprised that flow control isn't enabled by default, and the fact
that this differs between drivers is outright bizarre.

The flowcontrol option is also not mentioned in the media type
section of the drivers' man pages.  Until I stumbled over this
thread, I had no idea it existed.  I just blindly tried

# ifconfig nfe0 mediaopt flowcontrol

on a machine here and, lo and behold, it is successfully enabled.

Christian "naddy" Weisgerber                          naddy at

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