Re: [PATCH] KVM: x86: move MSR_IA32_POWER_CTL handling to common code

[Liran Alon]

> On 6 Jun 2019, at 15:33, Paolo Bonzini <pbonzini@xxxxxxxxxx> wrote:
> 
> Make it available to AMD hosts as well, just in case someone is trying
> to use an Intel processor's CPUID setup.

Iâm actually quite surprised that such a setup works properly.

> 
> Suggested-by: Sean Christopherson <sean.j.christopherson@xxxxxxxxx>
> Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>

Reviewed-by: Liran Alon <liran.alon@xxxxxxxxxx>

> ---
> arch/x86/include/asm/kvm_host.h | 1 +
> arch/x86/kvm/vmx/vmx.c          | 6 ------
> arch/x86/kvm/vmx/vmx.h          | 2 --
> arch/x86/kvm/x86.c              | 6 ++++++
> 4 files changed, 7 insertions(+), 8 deletions(-)
> 
> diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
> index a86026969b19..35e7937cc9ac 100644
> --- a/arch/x86/include/asm/kvm_host.h
> +++ b/arch/x86/include/asm/kvm_host.h
> @@ -689,6 +689,7 @@ struct kvm_vcpu_arch {
> 	u32 virtual_tsc_mult;
> 	u32 virtual_tsc_khz;
> 	s64 ia32_tsc_adjust_msr;
> +	u64 msr_ia32_power_ctl;
> 	u64 tsc_scaling_ratio;
> 
> 	atomic_t nmi_queued;  /* unprocessed asynchronous NMIs */
> diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
> index cccf73a91e88..5d903f8909d1 100644
> --- a/arch/x86/kvm/vmx/vmx.c
> +++ b/arch/x86/kvm/vmx/vmx.c
> @@ -1695,9 +1695,6 @@ static int vmx_get_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> 	case MSR_IA32_SYSENTER_ESP:
> 		msr_info->data = vmcs_readl(GUEST_SYSENTER_ESP);
> 		break;
> -	case MSR_IA32_POWER_CTL:
> -		msr_info->data = vmx->msr_ia32_power_ctl;
> -		break;
> 	case MSR_IA32_BNDCFGS:
> 		if (!kvm_mpx_supported() ||
> 		    (!msr_info->host_initiated &&
> @@ -1828,9 +1825,6 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> 	case MSR_IA32_SYSENTER_ESP:
> 		vmcs_writel(GUEST_SYSENTER_ESP, data);
> 		break;
> -	case MSR_IA32_POWER_CTL:
> -		vmx->msr_ia32_power_ctl = data;
> -		break;
> 	case MSR_IA32_BNDCFGS:
> 		if (!kvm_mpx_supported() ||
> 		    (!msr_info->host_initiated &&
> diff --git a/arch/x86/kvm/vmx/vmx.h b/arch/x86/kvm/vmx/vmx.h
> index 61128b48c503..1cdaa5af8245 100644
> --- a/arch/x86/kvm/vmx/vmx.h
> +++ b/arch/x86/kvm/vmx/vmx.h
> @@ -260,8 +260,6 @@ struct vcpu_vmx {
> 
> 	unsigned long host_debugctlmsr;
> 
> -	u64 msr_ia32_power_ctl;
> -
> 	/*
> 	 * Only bits masked by msr_ia32_feature_control_valid_bits can be set in
> 	 * msr_ia32_feature_control. FEATURE_CONTROL_LOCKED is always included
> diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
> index 145df9778ed0..5ec87ded17db 100644
> --- a/arch/x86/kvm/x86.c
> +++ b/arch/x86/kvm/x86.c
> @@ -2563,6 +2563,9 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> 			return 1;
> 		vcpu->arch.smbase = data;
> 		break;
> +	case MSR_IA32_POWER_CTL:
> +		vcpu->arch.msr_ia32_power_ctl = data;
> +		break;
> 	case MSR_IA32_TSC:
> 		kvm_write_tsc(vcpu, msr_info);
> 		break;
> @@ -2822,6 +2825,9 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
> 			return 1;
> 		msr_info->data = vcpu->arch.arch_capabilities;
> 		break;
> +	case MSR_IA32_POWER_CTL:
> +		msr_info->data = vcpu->arch.msr_ia32_power_ctl;
> +		break;
> 	case MSR_IA32_TSC:
> 		msr_info->data = kvm_scale_tsc(vcpu, rdtsc()) + vcpu->arch.tsc_offset;
> 		break;
> -- 
> 1.8.3.1
>