Re: [PATCH 4/4] KVM: VMX: Add instruction rdtscp support for guest

[Avi Kivity <avi@redhat.com>]

On 12/17/2009 11:33 AM, Sheng Yang wrote:
> Before enabling, execution of "rdtscp" in guest would result in #UD.
>
> Signed-off-by: Sheng Yang<sheng@linux.intel.com>
> ---
>
> Reflect guest CPUID on vmcs fields as well, but it involved some more code
> which would only executed once... Do we need a callback there for post-"cpuid
> setting"?
>    

I guess we do need a callback.

> -		/* Otherwise falls through to kvm_set_msr_common */
> +		ret = kvm_set_msr_common(vcpu, msr_index, data);
> +		break;
> +	case MSR_TSC_AUX:
> +		if (!vcpu->arch.cpuid_rdtscp_enabled || !vmx_rdtscp_supported())
> +			return 1;
> +		/* Check reserved bit */
> +		if ((data&  0xffff0000) != 0)
> +			return 1;
>    

It's 0xffffffff00000000...

> @@ -913,6 +926,9 @@ static void setup_msrs(struct vcpu_vmx *vmx)
>   		index = __find_msr_index(vmx, MSR_CSTAR);
>   		if (index>= 0)
>   			move_msr_up(vmx, index, save_nmsrs++);
> +		index = __find_msr_index(vmx, MSR_TSC_AUX);
> +		if (index>= 0)
> +			move_msr_up(vmx, index, save_nmsrs++);
>    

Only do this if rdtscp is enabled!

-- 
error compiling committee.c: too many arguments to function