Features/XenPvopsDom0

Feature Name

Summary

Dom0 support for pvops-based kernel to support hosting of Xen guests which has been lacking since Fedora 8.

Owner

• Name: None

Previously involved: EduardoHabkost, MarkMcLoughlin, Stephen Tweedie, Chris Wright, Juan Quintela, Markus Armbruster, Glauber Costa, DanielBerrange, ...

Current status

• Last updated: 2009-07-15
• Percentage of completion: 0%
• Targeted release: F13
• Dom0 status: awaiting upstream kernel support
• Background:

Upstream status, XenParavirtOps on xenwiki,

Upstream patches:

• xen-tip/master - old known-working branch, with only tested changes
• xen-tip/next - old current bleeding edge; should at least compile
• rebase/master - new master branch; people should test this branch

• News: FWN #169, FWN #152, FWN #137

old status #1, old status #2, pv_ops dom0 status report, June 2009, pv_ops dom0 roadmap, August 2009

• M A Young has built unofficial pv_ops dom0 kernel RPMs for testing, available from his directory. For feedback or questions about these kernels you should email to fedora-xen or fedora-virt mailinglists. Note that these kernels are not meant for production use, they're only for beta testing, and as of 2009-08-11, only the 64-bit kernels are working (32-bit crashes, being worked on).
• If you want to build your own custom dom0 kernel, see the upstream XenDom0Kernels wiki page

Detailed Description

See Features/XenPvops for a rationale. This feature just continues the paravirt_ops Xen effort to bring it back to feature parity with Fedora 8 Xen.

Scope

Work items:

• Implement Dom0 support in upstream kernel (JeremyFitzhardinge)
• Allow the hypervisor to boot bzImage kernels (see this patch included since xen-3.3.1-3.fc11)
• Make 'new-kernel-pkg' aware of HYPERVISOR setting in /etc/sysconfig/xen
• Wait for that upstream kernel version to be pulled into Fedora

How To Test

• Install a Fedora host/Dom0 system
• Turn on Xen Hypervisor by setting 'HYPERVISOR=/boot/xen-3.3.gz' in /etc/sysconfig/kernel and running some tool (TBD)
• Turn on Xen Userspace by running 'chkconfig xend on'
• Reboot
• Observe presence of Xen via /sys/hypervisor/
• Run 'xm list' and observe Domain-0
• Use virt-install to deploy a Fedora 9/10 paravirt guest
• Use virt-install to deploy a Fedora 8 paravirt guest
• Use virt-install to deploy a Fedora 8/9/10 fullyvirt guest
• Use 'virsh' to save & restore a PV guest and HVM guest
• Balloon down memory of a guest with virsh.

User Experience

• Stock Fedora kernel supports Xen
• The Xen kernel does not lag behind the Fedora kernel
• All features and hardware supported on baremetal also works on Xen Dom0
• Can enable/disable use of HV via a /etc/sysconfig setting

Dependencies

• Update to 'new-kernel-pkg' to know how to install HV

Contingency Plan

If Dom0 support is not ready, continue the status quo of only shipping with DomU support.

Comments and Discussion

• See Talk:Features/YourFeatureName