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Revision as of 13:36, 11 August 2009 by Billmcgonigle (talk | contribs) (added note about 32/64-bit kernels in myoung tree)

Feature Name


Dom0 support for pvops-based Package-x-generic-16.pngkernel to support hosting of Xen guests which has been lacking since Fedora 8.


  • 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:
old status #1, old status #2, pv_ops dom0 status report, June 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.


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


  • 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.


Release Notes

Comments and Discussion