From 27cbe7d61898a1d1d39be32e5acff7d4be6e9d87 Mon Sep 17 00:00:00 2001 From: Liran Alon Date: Mon, 11 Nov 2019 11:16:40 +0200 Subject: [PATCH] KVM: x86: Prevent set vCPU into INIT/SIPI_RECEIVED state when INIT are latched Commit 4b9852f4f389 ("KVM: x86: Fix INIT signal handling in various CPU states") fixed KVM to also latch pending LAPIC INIT event when vCPU is in VMX operation. However, current API of KVM_SET_MP_STATE allows userspace to put vCPU into KVM_MP_STATE_SIPI_RECEIVED or KVM_MP_STATE_INIT_RECEIVED even when vCPU is in VMX operation. Fix this by introducing a util method to check if vCPU state latch INIT signals and use it in KVM_SET_MP_STATE handler. Fixes: 4b9852f4f389 ("KVM: x86: Fix INIT signal handling in various CPU states") Reported-by: Sean Christopherson Reviewed-by: Mihai Carabas Signed-off-by: Liran Alon Signed-off-by: Paolo Bonzini --- arch/x86/kvm/lapic.c | 2 +- arch/x86/kvm/x86.c | 8 ++++++-- arch/x86/kvm/x86.h | 5 +++++ 3 files changed, 12 insertions(+), 3 deletions(-) diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c index 87b0fcc23ef8..cacfe14717d6 100644 --- a/arch/x86/kvm/lapic.c +++ b/arch/x86/kvm/lapic.c @@ -2714,7 +2714,7 @@ void kvm_apic_accept_events(struct kvm_vcpu *vcpu) * KVM_MP_STATE_INIT_RECEIVED state), just eat SIPIs * and leave the INIT pending. */ - if (is_smm(vcpu) || kvm_x86_ops->apic_init_signal_blocked(vcpu)) { + if (kvm_vcpu_latch_init(vcpu)) { WARN_ON_ONCE(vcpu->arch.mp_state == KVM_MP_STATE_INIT_RECEIVED); if (test_bit(KVM_APIC_SIPI, &apic->pending_events)) clear_bit(KVM_APIC_SIPI, &apic->pending_events); diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index c5886eed3d57..34d9048c881e 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -8706,8 +8706,12 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, mp_state->mp_state != KVM_MP_STATE_RUNNABLE) goto out; - /* INITs are latched while in SMM */ - if ((is_smm(vcpu) || vcpu->arch.smi_pending) && + /* + * KVM_MP_STATE_INIT_RECEIVED means the processor is in + * INIT state; latched init should be reported using + * KVM_SET_VCPU_EVENTS, so reject it here. + */ + if ((kvm_vcpu_latch_init(vcpu) || vcpu->arch.smi_pending) && (mp_state->mp_state == KVM_MP_STATE_SIPI_RECEIVED || mp_state->mp_state == KVM_MP_STATE_INIT_RECEIVED)) goto out; diff --git a/arch/x86/kvm/x86.h b/arch/x86/kvm/x86.h index 2b0805012e3c..29391af8871d 100644 --- a/arch/x86/kvm/x86.h +++ b/arch/x86/kvm/x86.h @@ -258,6 +258,11 @@ static inline bool kvm_check_has_quirk(struct kvm *kvm, u64 quirk) return !(kvm->arch.disabled_quirks & quirk); } +static inline bool kvm_vcpu_latch_init(struct kvm_vcpu *vcpu) +{ + return is_smm(vcpu) || kvm_x86_ops->apic_init_signal_blocked(vcpu); +} + void kvm_set_pending_timer(struct kvm_vcpu *vcpu); void kvm_inject_realmode_interrupt(struct kvm_vcpu *vcpu, int irq, int inc_eip); -- GitLab