| Message ID | 1478713811-25147-1-git-send-email-jmattson@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
2016-11-09 09:50-0800, Jim Mattson: > From the Intel SDM, volume 3, section 10.4.3, "Enabling or Disabling the > Local APIC," > > When IA32_APIC_BASE[11] is 0, the processor is functionally equivalent > to an IA-32 processor without an on-chip APIC. The CPUID feature flag > for the APIC (see Section 10.4.2, "Presence of the Local APIC") is > also set to 0. > > Signed-off-by: Jim Mattson <jmattson@google.com> > --- Applied to kvm/queue, thanks. -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/arch/x86/kvm/cpuid.c b/arch/x86/kvm/cpuid.c index afa7bbb..84b62ee 100644 --- a/arch/x86/kvm/cpuid.c +++ b/arch/x86/kvm/cpuid.c @@ -81,6 +81,10 @@ int kvm_update_cpuid(struct kvm_vcpu *vcpu) best->ecx |= F(OSXSAVE); } + best->edx &= ~F(APIC); + if (vcpu->arch.apic_base & MSR_IA32_APICBASE_ENABLE) + best->edx |= F(APIC); + if (apic) { if (best->ecx & F(TSC_DEADLINE_TIMER)) apic->lapic_timer.timer_mode_mask = 3 << 17; diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 23b99f3..7bd887b 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -1748,14 +1748,17 @@ void kvm_lapic_set_base(struct kvm_vcpu *vcpu, u64 value) u64 old_value = vcpu->arch.apic_base; struct kvm_lapic *apic = vcpu->arch.apic; - if (!apic) { + if (!apic) value |= MSR_IA32_APICBASE_BSP; - vcpu->arch.apic_base = value; - return; - } vcpu->arch.apic_base = value; + if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE) + kvm_update_cpuid(vcpu); + + if (!apic) + return; + /* update jump label if enable bit changes */ if ((old_value ^ value) & MSR_IA32_APICBASE_ENABLE) { if (value & MSR_IA32_APICBASE_ENABLE) {
From the Intel SDM, volume 3, section 10.4.3, "Enabling or Disabling the Local APIC," When IA32_APIC_BASE[11] is 0, the processor is functionally equivalent to an IA-32 processor without an on-chip APIC. The CPUID feature flag for the APIC (see Section 10.4.2, "Presence of the Local APIC") is also set to 0. Signed-off-by: Jim Mattson <jmattson@google.com> --- arch/x86/kvm/cpuid.c | 4 ++++ arch/x86/kvm/lapic.c | 11 +++++++---- 2 files changed, 11 insertions(+), 4 deletions(-)