bhyve: Detecting that a guest kernel has booted

[Rodney W. Grimes]

> On Mon, Mar 11, 2019 at 10:58:55AM -0700, Rodney W. Grimes wrote:
> > -- Start of PGP signed section.
> > > On 2019-03-11T13:08:53 -0400
> > > Shawn Webb <shawn.webb at hardenedbsd.org> wrote:
> > > >
> > > > If your guest OS supports it, you could probably write two scripts that
> > > > uses virtio_console(4), one for the guest to tell the host "HELLO" and
> > > > one for the host to say "NICE TO SEE YOU!" once the guest's "HELLO" is
> > > > received.
> > > > 
> > > 
> > > They're a mix of FreeBSD, OpenBSD, and Debian guests. So I'm guessing
> > > one out of three of those supports it...
> > > 
> > > I suppose my other option would be to add (another) NFS mount in each
> > > guest, and have them touch a file early in the init script (and
> > > possibly touch a different file early in the shutdown script).
> > 
> > Well ICMP is in the kernel, and should be working as soon as the
> > interface is up, long before you could do anything with NFS,
> > so rather than the complexity above a simple ping would suffice.
> 
> Just a note: Windows systems disable inbound ICMP by default, but
> inbound ICMP support can be enabled post-installation.
> 
> > There is also the phase of vmm(8) startup that when you are
> > running bhyveload vs bhyve and iirc grubload vs bhyve, that
> > can be detected.  vmbhyve does so and says you are in state
> > looader when you do a vm list.
> 
> I would suggest using bhyve with UEFI. I wish a death upon bhyveload
> and grub2-bhyve.

I have no love for them either, but until we get our UEFI updated
it is a rather sad state of affairs.  If we could a) get on a modern
version of ed2k, and b) bet the CSM fixed so that we could actually
boot bios mode stuff with it and c) maybe make a port of seabios
that could be used then we would be kicking some seriuos stuff!

> Thanks,
> Shawn Webb

-- 
Rod Grimes                                                 rgrimes at freebsd.org