vnet jail shutdown crashes system

[Kyle Evans]

On Sun, Jun 7, 2020 at 8:59 PM David Mehler <dave.mehler at gmail.com> wrote:
>
> Hello,
>
> I've finally created a vnet jail on FreeBSD 12.1 that will get out to
> the internet. Whenever I atempt to shut it down the system crashes, I
> have no idea why.
>
> [... snip ...]
>
> I wish I knew why stopping this jail takes the whole system down,
> suggestions welcome.

Without seeing a panic message, this is almost certainly the ol' epair
teardown problem. I'm working toward a solution for it, but I'm still
needing to get people to review the prerequisite change to add a busy
mechanism to ifnet so that we can coordinate correctly.

You can work around it by destroying the epair interface visible there
on the host before you destroy the jail (and perhaps there's a better
way), though that's not necessarily ideal if you need networking to
work through a graceful shutdown.

Thanks,

Kyle Evans