Re: [PATCH] KVM: SVM: fix trashing of MSR_TSC_AUX

[Paolo Bonzini]

On 07/07/2016 13:47, Borislav Petkov wrote:
> On Thu, Jul 07, 2016 at 01:01:34PM +0200, Paolo Bonzini wrote:
>> We'll probably add -cpu Opteron_G2_rdtscp but we will indeed do
>> something like that.
> 
> Why a separate CPU model and not change the existing ones?

Because otherwise you couldn't do live migration from new QEMU + new
kernel to new QEMU + old kernel.  QEMU tries to avoid requiring lockstep
upgrades of QEMU and KVM (unlike for example perf).

Paolo