[libvirt-users] LibVirt query CPU Model support and restore operation

[Jiri Denemark]

On Fri, Jan 27, 2017 at 13:48:44 +0530, akhilesh rawat wrote:
> hello ,
> 
> thanks for comments .
> 
> I tried now with force options for CPU flag which were not supported . Now
> the command with non fully supported CPU model gets executed ,  But i am
> surprised to see that still Guest  cpu model is not changed and still same
> as host cpu model(SAndy Bridge)
> 
> Why don't i see the model as HAswell now , could you please comment.
> 
> Command used :
> 
> virt-install --virt-type kvm --name controller-0  --cpu
> Haswell-noTSX,+fma,+movbe,+fsgsbase,+bmi1,+avx2,+smep,+bmi2,+erms,+invpcid
> --ram=8120 --vcpus=4,sockets=1
> 
> Linux process for KVM :
> 
> 7479     1 37 10:13 ?        01:13:21 /usr/libexec/qemu-kvm -name
> controller-0 -S -machine pc-i440fx-rhel7.0.0,accel=kvm,usb=off *-cpu
> SandyBridge,*+fma,+pcid,+movbe,+fsgsbase,+bmi1,+avx2,+smep,+bmi2,+erms,+invpcid
> -m 8120 -realtime mlock=off -smp 4,sockets=1,cores=4,threads=1

Your qemu-kvm binary apparently doesn't know what Haswell-noTSX is and
thus libvirt has to translate it to something QEMU understands. You can
check supported CPU models with "/usr/libexec/qemu-kvm -cpu ?" (make
sure the question mark is not expanded by the shell).

Jirka