I installed Virt-Manager on Kali (basically Debian), When I try to finish creation of a new VM from an iso, I get this error:

'internal error: process exited while connecting to monitor:
2018-04-11T00:42:51.993762Z qemu-system-x86_64: can't apply global
IvyBridge-x86_64-cpu.spec-ctrl=on: Property '.spec-ctrl' not found'

Traceback (most recent call last): File
"/usr/share/virt-manager/virtManager/asyncjob.py", line 89, in
cb_wrapper
callback(asyncjob, *args, **kwargs) File "/usr/share/virt-manager/virtManager/create.py", line 2545, in
_do_async_install
guest.start_install(meter=meter) File "/usr/share/virt-manager/virtinst/guest.py", line 498, in
start_install
doboot, transient) File "/usr/share/virt-manager/virtinst/guest.py", line 434, in
_create_guest
domain = self.conn.createXML(install_xml or final_xml, 0) File "/usr/lib/python2.7/dist-packages/libvirt.py", line 3659, in createXML
if ret is None:raise libvirtError('virDomainCreateXML() failed', conn=self) libvirtError: internal error: process exited while
connecting to monitor: 2018-04-11T00:42:51.993762Z qemu-system-x86_64:
can't apply global IvyBridge-x86_64-cpu.spec-ctrl=on: Property
'.spec-ctrl' not found

what can I do for make it work?

Issue at Hand

According to the error you have posted this is hardly a problem limited to Kali Linux. It appears certain patches for spectre/meltdown have created an issue with the kernel and virtual machines.

I have found several links pertaining to this exact issue, all on different operating systems. Here is a link to a bug report for Red Hat. This link is to a forum post describing a solution for Arch Linux. Here is another forum post for a possible solution to the same error but for Manjaro. Someone using ParrotSec also reports the issue. Lastly I am including a link to the QEMU Wiki on CPU features as it also appears related. I suggest you read through each link first but from that quick search I was able to find some possible solutions to your problem.

1. Use the "copy host CPU configuration"

If you are launching a VM via the graphical interface of virt-manager try setting the "copy host CPU configuration" option under the CPU sub-menu of your Virtual Machine configuration menu. According to the provided links, this appears to be the best solution to the error you are encountering.

2. Missing permissions of Users and Groups

Make sure that your user launching KVM virt-manager is a member of the kvm and libvirt groups and try again.

3. Out of Date Versions

According to Jiri Denemark, the issue could lie with there being a problem with the kernel not supporting the newer CPU features.

This would suggest libvirt detected the new feature in the host CPU via CPUID, but the kernel is not new enough to recognize it. Moreover, qemu-kvm-rhev is pretty old and doesn't support the new feature either:

• Fri Mar 24 2017 Miroslav Rezanina - rhev-2.6.0-28.el7_3.9

I think virt-install by default takes the CPU model from libvirt's capabilities XML, which is Broadwell-IBRS. Since qemu-kvm-rhev does not support the new CPU model, libvirt uses Broadwell,+spec-ctrl,+rtm,+hle instead.

In other words, this was just a temporary issue with the compose when libvirt is updated while others are not updated yet. The problem can be fixed by detecting CPU capabilities via QEMU and teaching virt-install to use the CPU from domain capabilities. Libvirt does so with QEMU-2.10.

Try making sure you have the latest version of the Kernel, your kernel headers, libvirt, virt-manager, and QEMU. Reboot after this and try again.

Conclusion

I believe option 1 to be your best bet. If not make sure you have everything correctly installed and up to date. The error message you are getting is very descriptive of the problem you have. Verify that the processor feature set it says it is using matches your hardware. Google is your friend. As always, if there are any misconceptions or issues with my answer please comment, I appreciate corrections to my mistakes. Best of Luck!