KVM: x86: ignore APICv if LAPIC is not enabled
authorPaolo Bonzini <pbonzini@redhat.com>
Wed, 17 Nov 2021 12:35:44 +0000 (07:35 -0500)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Wed, 8 Dec 2021 08:04:43 +0000 (09:04 +0100)
commit 78311a514099932cd8434d5d2194aa94e56ab67c upstream.

Synchronize the two calls to kvm_x86_sync_pir_to_irr.  The one
in the reenter-guest fast path invoked the callback unconditionally
even if LAPIC is present but disabled.  In this case, there are
no interrupts to deliver, and therefore posted interrupts can
be ignored.

Cc: stable@vger.kernel.org
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
arch/x86/kvm/x86.c

index 16c7465619f7a2d295f151d601eaf6f7817ff349..8acbb1093966236966ecccdd7d0e276b2311435e 100644 (file)
@@ -9723,7 +9723,7 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
                if (likely(exit_fastpath != EXIT_FASTPATH_REENTER_GUEST))
                        break;
 
-               if (vcpu->arch.apicv_active)
+               if (kvm_lapic_enabled(vcpu) && vcpu->arch.apicv_active)
                        static_call(kvm_x86_sync_pir_to_irr)(vcpu);
 
                if (unlikely(kvm_vcpu_exit_request(vcpu))) {