Re: [PATCH v5 untested] kvm: better MWAIT emulation for guests

From: Joerg Roedel
Date: Tue Mar 21 2017 - 12:17:02 EST


On Wed, Mar 15, 2017 at 11:22:18PM +0200, Michael S. Tsirkin wrote:
> diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
> index d1efe2c..18e53bc 100644
> --- a/arch/x86/kvm/svm.c
> +++ b/arch/x86/kvm/svm.c
> @@ -1198,8 +1198,6 @@ static void init_vmcb(struct vcpu_svm *svm)
> set_intercept(svm, INTERCEPT_CLGI);
> set_intercept(svm, INTERCEPT_SKINIT);
> set_intercept(svm, INTERCEPT_WBINVD);
> - set_intercept(svm, INTERCEPT_MONITOR);
> - set_intercept(svm, INTERCEPT_MWAIT);

Why do you remove the intercepts for AMD? The new kvm_mwait_in_guest()
function will always return false on AMD anyway, and on Intel you re-add
the intercepts for !kvm_mwait_in_guest().


Joerg