On 2013-08-07 11:06, Peter Grehan wrote:
Hi Rob,

Bhyve generates the following error after the bootloader screen:

4 vCPUs requested but only 1 available

 What this means is that the model of CPU that you have doesn't
support the "unrestricted guest" feature, which allows a guest to run
in 16-bit mode.

 bhyve boots FreeBSD directly into 64-bit mode on the main CPU, but
secondary CPUs are started through a boostrap from 16-bit mode to
64-bit mode. There was a hack early on in bhyve to avoid this by
starting the secondaries directly in 64-bit mode, but it was bhyve-
and FreeBSD-specific and difficult to maintain. Given that there was
only a small timeframe of CPUs that supported EPT but not unrestricted
guest (early Nehalems), we decided to the 64-bit AP spinup.

 You can still run single vCPU guests though.

The Virtualbox logs below show EPT in use:

 On the issue of running VBox and bhyve at the same time: that's not
recommended and will probably result in a crash. To do this requires
cooperation from hypervisors in that they will completely flush state
any time they could be context-switched away to avoid the other
hypervisor's state from colliding. This results in poor performance
which is why it usually isn't done by default.

 I think we know how to fix this in bhyve, but aren't there yet.




Thanks for your answer, this clears things up, I was under the impression that EPT support automatically included the "unrestricted guest" feature. Unfortunately I'll have to stick with Virtualbox as I need multiple CPU support for my vm's.

Thanks for the great software though, I'll be back running bHyve once I get my hands on a more capable machine!

Rob Evers

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