linux-kernel - [PATCH v2 15/30] KVM: x86: hyper-v: Honor HV_ACCESS

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Message-Id: <20210521095204.2161214-16-vkuznets@redhat.com>
Date:   Fri, 21 May 2021 11:51:49 +0200
From:   Vitaly Kuznetsov <vkuznets@...hat.com>
To:     kvm@...r.kernel.org, Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <seanjc@...gle.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Siddharth Chandrasekaran <sidcha@...zon.de>,
        linux-kernel@...r.kernel.org
Subject: [PATCH v2 15/30] KVM: x86: hyper-v: Honor HV_ACCESS_REENLIGHTENMENT privilege bit

HV_X64_MSR_REENLIGHTENMENT_CONTROL/HV_X64_MSR_TSC_EMULATION_CONTROL/
HV_X64_MSR_TSC_EMULATION_STATUS are only available to guest when
HV_ACCESS_REENLIGHTENMENT bit is exposed.

Signed-off-by: Vitaly Kuznetsov <vkuznets@...hat.com>
---
 arch/x86/kvm/hyperv.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/arch/x86/kvm/hyperv.c b/arch/x86/kvm/hyperv.c
index 8821981e17d3..f416c9de73cb 100644
--- a/arch/x86/kvm/hyperv.c
+++ b/arch/x86/kvm/hyperv.c
@@ -1248,6 +1248,11 @@ static bool hv_check_msr_access(struct kvm_vcpu_hv *hv_vcpu, u32 msr)
 	case HV_X64_MSR_APIC_FREQUENCY:
 		return hv_vcpu->cpuid_cache.features_eax &
 			HV_ACCESS_FREQUENCY_MSRS;
+	case HV_X64_MSR_REENLIGHTENMENT_CONTROL:
+	case HV_X64_MSR_TSC_EMULATION_CONTROL:
+	case HV_X64_MSR_TSC_EMULATION_STATUS:
+		return hv_vcpu->cpuid_cache.features_eax &
+			HV_ACCESS_REENLIGHTENMENT;
 	default:
 		break;
 	}
-- 
2.31.1