Chapter 35. Virtualization

SMEP and SMAP bits masked to enable secondary vCPUs

Previously, disabling Extended Page Table (EPT) on a host that supported Supervisor Mode Execution Protection (SMEP) or Supervisor Mode Access Protection (SMAP) resulted in guests being restricted to a single vCPU. This update masks SMEP and SMAP bits on the host side when necessary. As a result, secondary vCPUs start and can be used by the guest virtual machine. (BZ#1273807)

Force Reset menu entry in Japanese locale Virtual Machine Manager translated correctly

Previously, the Force Reset menu entry was translated incorrectly in the Japanese locale Virtual Machine Manager. In this update the Force Reset menu entry is translated correctly. (BZ#1282276)

Limited KSM deduplication factor

Previously, the kernel same-page merging (KSM) deduplication factor was not explicitly limited, which caused Red Hat Enterprise Linux hosts to have performance problems or become unresponsive in case of high workloads. This update limits the KSM deduplication factor, and thus eliminates the described problems with virtual memory operations related to KSM pages. (BZ#1298618)

VMDK images with streamOptimized sub-format are accepted

Previously, a Virtual Machine Disk (VMDK) image with a streamOptimized sub-format created by the qemu-img tool was rejected by Elastic Sky X (ESX) services, because the version number of the VMDK image was too low. In this update, the sub-format number of streamOptimized VMDK images are automatically increased. This results in the VMDK image being accepted by ESX services. (BZ#1299116)

Data layout of VMDK images with streamOptimized sub-format was incorrect

Previously, the data layout of a Virtual Machine Disk (VMDK) image with a streamOptimized sub-format created by the qemu-img tool was incorrect. This prevented the VMDK image from being bootable when imported to ESX servers. In this update, the image is converted to a valid VMDK streamOptimized image. This results in the VMDK image being bootable. (BZ#1299250)

blockcopy with --pivot option no longer fails

Previously, blockcopy always failed when the --pivot option was specified. With this release, the libvirt package was updated to prevent this issue. blockcopy can now be used with the --pivot option. (BZ#1197592)

Guest display problems after virt-v2v conversion have been fixed

Previously, the video card driver setting of a guest converted with the virt-v2v utility was ignored, causing various display problems in the guest. This update ensures that virt-v2v generates the libvirt XML file for the converted guest properly. As a result, the video card setting is preserved, and the guest can take full advantage of graphical capabilities after the conversion. (BZ#1225789)

Migrating MSR_TSC_AUX works properly

Previously, the contents of the MSR_TSC_AUX file were sometimes not migrated correctly during guest migration. As a consequence, the guest terminated unexpectedly after the migration finished. This update ensures that the contents of MSR_TSC_AUX are migrated as expected, and the described crashes no longer occur. (BZ#1265427)

Windows guest virtual machine information removed from documentation

In this update, all references to Windows guest virtual machines have been removed from the documentation. The information was moved to the following knowledgebase article: https://access.redhat.com/articles/2470791 (BZ#1262007)

Accessing guest disks on virt-manager works properly with SELinux and libguestfs-python

Prior to this update, when the libguestfs-python package was installed and SELinux was enabled on the host machine, accessing guest disks using the virt-manager interface caused I/O failures. Now, virt-manager and the libguestfs library share the same libvirt connection, which prevents the described failures from occurring. (BZ#1173695)