linux-kernel - [PATCH v2 54/66] KVM: x86: Use KVM cpu caps to detect MSR_TSC

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Date:   Mon,  2 Mar 2020 15:56:57 -0800
From:   Sean Christopherson <sean.j.christopherson@...el.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     Sean Christopherson <sean.j.christopherson@...el.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, Xiaoyao Li <xiaoyao.li@...el.com>
Subject: [PATCH v2 54/66] KVM: x86: Use KVM cpu caps to detect MSR_TSC_AUX virt support

Check for MSR_TSC_AUX virtualization via kvm_cpu_cap_has() and drop
->rdtscp_supported().

Note, vmx_rdtscp_supported() needs to hang around a tiny bit longer due
other usage in VMX code.

No functional change intended.

Reviewed-by: Vitaly Kuznetsov <vkuznets@...hat.com>
Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/include/asm/kvm_host.h | 1 -
 arch/x86/kvm/svm.c              | 6 ------
 arch/x86/kvm/vmx/vmx.c          | 3 ---
 arch/x86/kvm/x86.c              | 2 +-
 4 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/arch/x86/include/asm/kvm_host.h b/arch/x86/include/asm/kvm_host.h
index eecc6afdd9a6..25d9a0d45cc6 100644
--- a/arch/x86/include/asm/kvm_host.h
+++ b/arch/x86/include/asm/kvm_host.h
@@ -1149,7 +1149,6 @@ struct kvm_x86_ops {
 	int (*get_tdp_level)(struct kvm_vcpu *vcpu);
 	u64 (*get_mt_mask)(struct kvm_vcpu *vcpu, gfn_t gfn, bool is_mmio);
 	int (*get_lpage_level)(void);
-	bool (*rdtscp_supported)(void);
 
 	void (*set_tdp_cr3)(struct kvm_vcpu *vcpu, unsigned long cr3);
 
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index d351007eb7f9..692b8ffdbad3 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -6070,11 +6070,6 @@ static int svm_get_lpage_level(void)
 	return PT_PDPE_LEVEL;
 }
 
-static bool svm_rdtscp_supported(void)
-{
-	return boot_cpu_has(X86_FEATURE_RDTSCP);
-}
-
 static bool svm_pt_supported(void)
 {
 	return false;
@@ -7439,7 +7434,6 @@ static struct kvm_x86_ops svm_x86_ops __ro_after_init = {
 
 	.cpuid_update = svm_cpuid_update,
 
-	.rdtscp_supported = svm_rdtscp_supported,
 	.pt_supported = svm_pt_supported,
 
 	.set_supported_cpuid = svm_set_supported_cpuid,
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index d5a5e8f987c8..f168da6f9b89 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7935,9 +7935,6 @@ static struct kvm_x86_ops vmx_x86_ops __ro_after_init = {
 	.get_lpage_level = vmx_get_lpage_level,
 
 	.cpuid_update = vmx_cpuid_update,
-
-	.rdtscp_supported = vmx_rdtscp_supported,
-
 	.set_supported_cpuid = vmx_set_supported_cpuid,
 
 	.has_wbinvd_exit = cpu_has_vmx_wbinvd_exit,
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index df0c1b387400..e2c3f1b69e25 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5200,7 +5200,7 @@ static void kvm_init_msr_list(void)
 				continue;
 			break;
 		case MSR_TSC_AUX:
-			if (!kvm_x86_ops->rdtscp_supported())
+			if (!kvm_cpu_cap_has(X86_FEATURE_RDTSCP))
 				continue;
 			break;
 		case MSR_IA32_RTIT_CTL:
-- 
2.24.1