Domain Patches

[Kyle Evans]

Hi,

I have a couple of domain patches in review, if anyone would like to
comment/review the area:

https://reviews.freebsd.org/D25062 adds a dom_probe callback so that
domains can indicate whether they should be supported at all or not.
This avoids some dirty stuff in domains that may not be supported
based on the hardware that's present (e.g. hvsock included in the
review, which shouldn't be available outside of HyperV). Instead of
having to account for circumstances like that in individual callbacks,
this is a single hammer to prevent any further reach into the domain.

D25062 also updates domain(9) to reflect some changes from the past 11
years (splitting initialization out into domain_init, dom_destroy
addition).

https://reviews.freebsd.org/D25459 should make it safe to add domains
after domainfinalize (i.e. they can be loadable at runtime). The big
issue with doing this previously is that pfslowtimo/pffasttimo have
already been setup and may be called on domains that aren't completely
initialized. There are some additional races re: socket creation that
should be addressed, but this review should be sufficient for at least
removing the warning.

Thanks,

Kyle Evans