[libvirt-users] Why Guest does not retain Host CPU flags

[akhilesh rawat]

ok thanks , but then can we know which all list of feature are supported by
QEMU/KVM release.
http://www.linux-kvm.org/page/KVM_Features
Does not seem to be all corect .



On Thu, Feb 16, 2017 at 3:42 PM, Jiri Denemark <jdenemar at redhat.com> wrote:

> On Mon, Feb 06, 2017 at 09:51:06 +0530, akhilesh rawat wrote:
> > hi ,
> >
> > I am creating Guest by Libvirt tool " virt-install"  with cpu model as
> > host.
> >
> > After Guest creation i see Guest Missing quite no of flags which Host was
> > having .
> >
> > What could be the reason for this ?  I am expecting all flags of Host to
> e
> > present in Guest as well when choosing cpu model as host .
>
> Even if you request "host" CPU model, the guest will always see only a
> subset of features the host supports. Not all features can be used in a
> virtual machine and even if they can be used they usually need some
> support form KVM or QEMU or both. That is both KVM and QEMU will filter
> out features they cannot currently virtualize and thus you will get a
> smaller set in comparison to the host CPU.
>
> Jirka
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/libvirt-users/attachments/20170217/34d741d2/attachment.htm>