Subject: Xen3 domain0 support is there !
To: None <>
From: Manuel Bouyer <>
List: port-xen
Date: 07/03/2006 00:05:54
I'm proud to announce that, with today's commit NetBSD has finally usable
Xen3 domain0 support. I have a NetBSD-current domU, acting as a NFS server
for a linux domU doing a release with sources on NFS and obj on
local storage, all running on NetBSD-current domain0 on Xen3 !

I added a XEN3_DOM0 kernel config file to i386, which will be build
as part of release (the next build should have a netbsd-XEN3_DOM0.gz
in pub/NetBSD-daily/HEAD/... on the ftp server).
Installing a Xen3+NetBSD system is much like a Xen2+NetBSD, you just
need to install xentools30 instead of xentools20 from pkgsrc :)
You also need a xen 3.0.2-2 kernel, older or newer may not be compatible
with the 3.0.2-2 tools.
Also be aware that in addition to /etc/rc.d/xend start, you also
need /etc/rc.d/xenbackendd start. xenbackendd will call scripts from
/usr/pkg/etc/xen/scripts/ (by default) to setup device backends
(e.g. attach a file to a vnd, or a xvif to a bridge) for domUs.

For now, Xen3+NetBSD won't run (at last it doesn't on my system) on SMP
system, you have to disable SMP on the Xen command line. On my system,
the system locks up hard a few seconds after boot. I suspect an interrupt
routing issue, our PCI_INTR_FIXUP needs more work for the Xen case.
This is what I'll work on next.

After that, there are (in no particular order):
- SMP support in NetBSD/Xen kernels, so that we can run NetBSD domains with
  more than one virtual CPU
- look at other Xen3 feature (suspend/resume, export PCI to domU, USB ?,
  VT-x, ...)
- port to x86_64. 

Manuel Bouyer <>
     NetBSD: 26 ans d'experience feront toujours la difference