VMX, SVM, or other CPU flags missing after updating Xen

  • 7001447
  • 29-Sep-2008
  • 25-Jul-2017


Novell SUSE Linux Enterprise Server 10 Service Pack 2
Novell SUSE Linux Enterprise Desktop 10 Service Pack 2
Novell ZENworks Orchestrator
PC (x86-32 or x86-64) hardware supporting full hardware virtualization (HVM).



The Xen hypervisor (package xen) and/or the Xen-enabled kernel (packages kernel-xenpae and kernel-xen) were updated on a system running a SLE10 SP2 based product.

  • The CPU capabilities stated in /proc/cpuinfo are missing flags which have been reported before, in particular the vmx flag (Intel CPUs), or the svm flag (AMD CPUs) is missing.
  • It is not possible to install a fully virtualized system on appropriate hardware.
  • When Xen live migration is set up, live migration may fail.
  • When ZENworks Orchestrator is used, virtual machine images which require full virtualization may be marked as unavailable, or may be unable to migrate, with a ERROR: Host lacks HVM support being reported.


This issue is fixed as of version of the kernel-xenpae and kernel-xen packages.

Additional Information

Live migration - detailed symptoms

When live migration of a Xen VM fails due to this issue, a traceback similar to the following may be logged on the node on which the VM was running:
[2008-11-19 07:08:34 8011] INFO (XendCheckpoint:373) All memory is saved
[2008-11-19 07:08:34 8011] INFO (XendCheckpoint:373) Save exit rc=0
[2008-11-19 07:08:35 8011] ERROR (XendCheckpoint:144) Save failed on domain
vm-hagbard (22).
Traceback (most recent call last):
  File "/usr/lib64/python2.4/site-packages/xen/xend/XendCheckpoint.py", line 122, in save
    write_exact(fd, buf, "could not write device model state")
  File "/usr/lib64/python2.4/site-packages/xen/xend/XendCheckpoint.py", line 43, in write_exact
    raise XendError(errmsg)
XendError: could not write device model state
and messages similar to the following being logged on the node onto which the VM was to be migrated:
[2008-11-19 07:08:34 8251] INFO (XendCheckpoint:373) Received all pages (0 races)
[2008-11-19 07:08:34 8251] INFO (XendCheckpoint:373) ERROR Internal error: error setting the HVM context
[2008-11-19 07:08:35 8251] INFO (XendCheckpoint:373) Restore exit with rc=1