[PATCH 5.15 70/83] KVM: x86: Hide IA32_PLATFORM_DCA_CAP[31:0] from the guest

[Greg Kroah-Hartman]

From: Jim Mattson <jmattson@xxxxxxxxxx>

[ Upstream commit aae2e72229cdb21f90df2dbe4244c977e5d3265b ]

The only thing reported by CPUID.9 is the value of
IA32_PLATFORM_DCA_CAP[31:0] in EAX. This MSR doesn't even exist in the
guest, since CPUID.1:ECX.DCA[bit 18] is clear in the guest.

Clear CPUID.9 in KVM_GET_SUPPORTED_CPUID.

Fixes: 24c82e576b78 ("KVM: Sanitize cpuid")
Signed-off-by: Jim Mattson <jmattson@xxxxxxxxxx>
Message-Id: <20220922231854.249383-1-jmattson@xxxxxxxxxx>
Signed-off-by: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 arch/x86/kvm/cpuid.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c
index b17c9b00669e..d85a0808a446 100644
--- a/arch/x86/kvm/cpuid.c
+++ b/arch/x86/kvm/cpuid.c
@@ -718,8 +718,6 @@ static inline int __do_cpuid_func(struct kvm_cpuid_array *array, u32 function)
 			entry->edx = 0;
 		}
 		break;
-	case 9:
-		break;
 	case 0xa: { /* Architectural Performance Monitoring */
 		struct x86_pmu_capability cap;
 		union cpuid10_eax eax;
-- 
2.35.1