Commit 27cbe7d6 authored by Liran Alon's avatar Liran Alon Committed by Paolo Bonzini
Browse files

KVM: x86: Prevent set vCPU into INIT/SIPI_RECEIVED state when INIT are latched 



Commit 4b9852f4 ("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: 4b9852f4 ("KVM: x86: Fix INIT signal handling in various CPU states")
Reported-by: default avatarSean Christopherson <sean.j.christopherson@intel.com>
Reviewed-by: default avatarMihai Carabas <mihai.carabas@oracle.com>
Signed-off-by: default avatarLiran Alon <liran.alon@oracle.com>
Signed-off-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
parent ff90afa7

arch/x86/kvm/lapic.c

+1 −1
Original line number Diff line number Diff line
@@ -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);

arch/x86/kvm/x86.c

+6 −2
Original line number Diff line number Diff line
@@ -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;

arch/x86/kvm/x86.h

+5 −0
Original line number Diff line number Diff line
@@ -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);