Re: [Qemu-devel] Do I need update the microcode of virtual machine

[Paolo Bonzini]

On 18/01/2018 11:48, Li Qiang wrote:
> 
>     > But upon I update the centos guest, the host kvm/qemu has been updated.
>     > The IBPB_ENABLED and IBRS_ENABLED are both zero if I don't update the
>     > microcode in the guest. If I update the guest micorcode, the are both 1.
> 
>     What do you mean by "update the guest microcode"?  Did you mean host?
> 
> 
> No, here mean the guest. By overwrite guest's files in
> /lib/firmware/intel-ucode/ directory and "echo 1 >
> /sys/devices/system/cpu/microcode/reload" as Intel's instruction says.
> The host's kvm and qemu has been got updated before this.

No, that has no effect.

Paolo