linux-kernel - [PATCH 36/61] KVM: x86: Handle GBPAGE CPUID adjustment for EPT in VMX code

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Date:   Sat,  1 Feb 2020 10:51:53 -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
Subject: [PATCH 36/61] KVM: x86: Handle GBPAGE CPUID adjustment for EPT in VMX code

Move the clearing of the GBPAGE CPUID bit into VMX to eliminate an
instance of the undesirable "unsigned f_* = *_supported ? F(*) : 0"
pattern in the common CPUID handling code, and to pave the way toward
eliminating ->get_lpage_level().

No functional change intended.

Signed-off-by: Sean Christopherson <sean.j.christopherson@...el.com>
---
 arch/x86/kvm/cpuid.c   | 3 +--
 arch/x86/kvm/vmx/vmx.c | 2 ++
 2 files changed, 3 insertions(+), 2 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index f4a3655451dd..c74253202af8 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -416,8 +416,7 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 	int r, i, max_idx;
 	unsigned f_nx = is_efer_nx() ? F(NX) : 0;
 #ifdef CONFIG_X86_64
-	unsigned f_gbpages = (kvm_x86_ops->get_lpage_level() == PT_PDPE_LEVEL)
-				? F(GBPAGES) : 0;
+	unsigned f_gbpages = F(GBPAGES);
 	unsigned f_lm = F(LM);
 #else
 	unsigned f_gbpages = 0;
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index fcec3d8a0176..11b9c1e7e520 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -7125,6 +7125,8 @@ static void vmx_set_supported_cpuid(struct kvm_cpuid_entry2 *entry)
 	case 0x80000001:
 		if (!cpu_has_vmx_rdtscp())
 			cpuid_entry_clear(entry, X86_FEATURE_RDTSCP);
+		if (enable_ept && !cpu_has_vmx_ept_1g_page())
+			cpuid_entry_clear(entry, X86_FEATURE_GBPAGES);
 		break;
 	default:
 		break;
-- 
2.24.1