HEAD UP: non-MPSAFE network drivers to be disabled

[M. Warner Losh]

In message: <20080526162427.X26343 at fledge.watson.org>
            Robert Watson <rwatson at freebsd.org> writes:
: 
: On Mon, 26 May 2008, Bruce M. Simpson wrote:
: 
: >> Given that this is (a) 2008 and (b) 8.x we're talking about, are there 
: >> really that many consumers of SLIP to warrant it being carried forward at 
: >> all?
: >
: > It's kind of a basic. [C]SLIP has been historically handy to have around for 
: > situations which warrant it. Mind you, given that we have had tun(4) in the 
: > tree for years now, a userland implementation of SLIP is possible.
: >
: > As with all of these things it's down to someone sitting down and doing it.
: >
: > I'm not volunteering to support any of this as I don't use it myself (got 
: > enough on my plate), merely pointing out that support for SLIP in a system 
: > is something many people have taken for granted over the years, and for 
: > prototyping something or providing IP over a simple serial link without the 
: > configuration overhead of PPP, SLIP is something someone might be using.
: >
: > P.S. ahc(4) is commodity hardware, I think it can stay right where it is 
: > thank-you.
: 
: My suspicion is that getting SLIP basically working in userspace is fairly 
: straight forward,

SLiRP and friends have been doing this for years.  I made my living
for about a year working on TIA, which was a portable, userland
implementation of PPP and SLIP/CSLIP.  This was in about 1995 or so.
It isn't that hard...

: SLIP has its subtleties, but the current implementation is relatively 
: straight-forward, well-documented, etc.

Yes, especially CSLIP.  But frankly, they are a whole lot easier than
PPP to get up and going...

Warner