XEN vs XENHVM?

[Colin Percival]

On 12/13/13 18:23, Mason Loring Bliss wrote:
> I was psyched to see that GENERIC kernels in 10 have HVMXEN support by
> default, but then I was left a little confused.
> 
> What's the different between a kernel with options XEN and one with options
> HVMXEN?

The XEN option is for *paravirtualized* Xen -- aka. the original version,
before Intel and AMD added virtualization support into their CPUs.  HVM
uses "hardware virtualization", but we also use PV drivers where available.

> I'd love to be able to run FreeBSD domU systems without having to do
> a custom compile whenever there's an update. I've got a 9.1 system running
> now, using a copy of the XEN config with a couple tweaks, and I see all the
> PV drivers I expect. I'm wondering what's different with XENHVM... Also
> useful would be knowing if there are remaining differences between i386 and
> amd64 as a domU in FreeBSD 10.

You want to switch to using HVM with PV devices.  That should be a simple
tweak to your Xen configuration, and then you'll be able to use a GENERIC
kernel.

-- 
Colin Percival
Security Officer Emeritus, FreeBSD | The power to serve
Founder, Tarsnap | www.tarsnap.com | Online backups for the truly paranoid