From e8457c67a4ec1268ec616bd8be1d9f1cc20f1493 Mon Sep 17 00:00:00 2001 From: Jan Kiszka Date: Sun, 14 Apr 2013 12:12:48 +0200 Subject: [PATCH] KVM: nVMX: Fix conditions for interrupt injection If we are entering guest mode, we do not want L0 to interrupt this vmentry with all its side effects on the vmcs. Therefore, injection shall be disallowed during L1->L2 transitions, as in the previous version. However, this check is conceptually independent of nested_exit_on_intr, so decouple it. If L1 traps external interrupts, we can kick the guest from L2 to L1, also just like the previous code worked. But we no longer need to consider L1's idt_vectoring_info_field. It will always be empty at this point. Instead, if L2 has pending events, those are now found in the architectural queues and will, thus, prevent vmx_interrupt_allowed from being called at all. Signed-off-by: Jan Kiszka Signed-off-by: Gleb Natapov --- arch/x86/kvm/vmx.c | 20 ++++++++++++-------- 1 file changed, 12 insertions(+), 8 deletions(-) diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c index 4fb72a764dbd..5e6391112275 100644 --- a/arch/x86/kvm/vmx.c +++ b/arch/x86/kvm/vmx.c @@ -4325,16 +4325,20 @@ static void vmx_set_nmi_mask(struct kvm_vcpu *vcpu, bool masked) static int vmx_interrupt_allowed(struct kvm_vcpu *vcpu) { - if (is_guest_mode(vcpu) && nested_exit_on_intr(vcpu)) { + if (is_guest_mode(vcpu)) { struct vmcs12 *vmcs12 = get_vmcs12(vcpu); - if (to_vmx(vcpu)->nested.nested_run_pending || - (vmcs12->idt_vectoring_info_field & - VECTORING_INFO_VALID_MASK)) + + if (to_vmx(vcpu)->nested.nested_run_pending) return 0; - nested_vmx_vmexit(vcpu); - vmcs12->vm_exit_reason = EXIT_REASON_EXTERNAL_INTERRUPT; - vmcs12->vm_exit_intr_info = 0; - /* fall through to normal code, but now in L1, not L2 */ + if (nested_exit_on_intr(vcpu)) { + nested_vmx_vmexit(vcpu); + vmcs12->vm_exit_reason = + EXIT_REASON_EXTERNAL_INTERRUPT; + vmcs12->vm_exit_intr_info = 0; + /* + * fall through to normal code, but now in L1, not L2 + */ + } } return (vmcs_readl(GUEST_RFLAGS) & X86_EFLAGS_IF) && -- 2.11.0