making SCTP loadable and removing it from GENERIC

[Mark Johnston]

On Thu, Jul 09, 2020 at 11:36:34PM +0700, Eugene Grosbein wrote:
> 09.07.2020 22:41, Michael Tuexen wrote:
> 
> >> I am wondering if anyone has any objections to or concerns about this
> >> proposal.  Any feedback is appreciated.
> 
> I'm for it.
> 
> > maybe it is acceptable to document user visible changes. This could include
> > * parameter tunings in /etc/sysctl.conf are only applied if the SCTP module
> >   is loaded from /etc/loader.conf.
> 
> You mean /boot/loader.conf.
> 
> This may be relaxed with "sctp_enable" knob for /etc/rc.conf and new startup script
> /etc/rc.d/sctp that: a) REQUIRE: kld; b) checks if sctp.ko already loaded and load it as needed;
> c) applies sctp sysctl tuning from /etc/sysctl.conf for values that differ.

Michael and I talked about this a bit in the past.  I propose a more
general solution, since it is a problem not just for SCTP:
https://reviews.freebsd.org/D25601