From 58cb628dbe24ce21b884729aebe15acb903dbfb5 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Fri, 24 Jan 2014 16:48:44 +0100 Subject: KVM: x86: Validate guest writes to MSR_IA32_APICBASE Check for invalid state transitions on guest-initiated updates of MSR_IA32_APICBASE. This address both enabling of the x2APIC when it is not supported and all invalid transitions as described in SDM section 10.12.5. It also checks that no reserved bit is set in APICBASE by the guest. Signed-off-by: Jan Kiszka [Use cpuid_maxphyaddr instead of guest_cpuid_get_phys_bits. - Paolo] Signed-off-by: Paolo Bonzini --- arch/x86/kvm/cpuid.h | 8 ++++++++ 1 file changed, 8 insertions(+) (limited to 'arch/x86/kvm/cpuid.h') diff --git a/arch/x86/kvm/cpuid.h b/arch/x86/kvm/cpuid.h index f1e4895174b2..a2a1bb7ed8c1 100644 --- a/arch/x86/kvm/cpuid.h +++ b/arch/x86/kvm/cpuid.h @@ -72,4 +72,12 @@ static inline bool guest_cpuid_has_pcid(struct kvm_vcpu *vcpu) return best && (best->ecx & bit(X86_FEATURE_PCID)); } +static inline bool guest_cpuid_has_x2apic(struct kvm_vcpu *vcpu) +{ + struct kvm_cpuid_entry2 *best; + + best = kvm_find_cpuid_entry(vcpu, 1, 0); + return best && (best->ecx & bit(X86_FEATURE_X2APIC)); +} + #endif -- cgit v1.2.3