Re: [libvirt] [PATCH 20/23] cputest: Update Xeon-E3-1245 data
On Thu, Oct 12, 2017 at 18:22:54 -0400, John Ferlan wrote:
On 10/04/2017 10:58 AM, Jiri Denemark wrote:
> xsaves is supported by current QEMU/KVM on this CPU.
Current as of when?
Good question. The QEMU version (unknown) used to generate the original
test data did not enable xsaves on the host while the version (also
unknown) used to regenerate them enabled this feature. It's also
possible the host is actually not exactly the same even though it has
the same CPU model. I'm not sure if any configuration can influence
availability of xsaves for guests. Perhaps I could have used different
words in the commit message...
Does this cause migration issues to have one version support and
another not? What about save/restore type operations?
It should cause any trouble. This is the point of all the code and these
tests after all. When starting a domain we record what features were or
were not really enabled in the virtual CPU and record this in domain XML
so that we can ask for exactly the same CPU configuration during
migration, restore, or snapshot revert.
Jirka