Ubuntu
linux package

  1. Oneiric (11.10)
  2. Bug #1044550
  3. Comment #0

Comment 0 for bug 1044550

Revision history for this message
Stefan Bader (smb) wrote :

SRU Justification:
There has been an issue with older Xen hypervisors (Xen 3.x) which caused guest crashes with pv-ops kernels. For that we are carrying a patch borrowed from Fedora which masks off the OSXSAVE bit on CR4 writes. However there have been issues with that recently which were caused by user-space checking other flags and then trying to use the feature which then broke because it was not activated correctly.

For Quantal we have now made the work-around patch better by not masking CR4 writes but actually removing the cpuid capability bits (and only for pre-4.x versions of Xen). This now needs to go back into previous releases.