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

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Environment

SUSE Linux Enterprise Server 10 Service Pack 2

SUSE Linux Enterprise Desktop 10 Service Pack 2

Situation

Changes

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.

Symptoms

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.

Resolution

This issue is fixed as of version 2.6.16.60-0.33 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

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