KVM: VMX: Move nmi injection failure processing to vm exit path

Instead of processing nmi injection failure in the vm entry path, move
it to the vm exit path (vm_complete_interrupts()).  This separates nmi
injection from nmi post-processing, and moves the nmi state from the VT
state into vcpu state (new variable nmi_injected specifying an injection
in progress).

Signed-off-by: Avi Kivity <avi@qumranet.com>

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 2adfacb003367dc546278489881bdcf960c96de5..ce13b53d21c4ad361fabd06085e9235189429e48 100644 (file)
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -2151,7 +2151,6 @@ static void vmx_inject_nmi(struct kvm_vcpu *vcpu)
 {
        vmcs_write32(VM_ENTRY_INTR_INFO_FIELD,
                        INTR_TYPE_NMI_INTR | INTR_INFO_VALID_MASK | NMI_VECTOR);
-       vcpu->arch.nmi_pending = 0;
 }
 
 static void kvm_do_inject_irq(struct kvm_vcpu *vcpu)
@@ -2820,8 +2819,11 @@ static void enable_intr_window(struct kvm_vcpu *vcpu)
 static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
 {
        u32 exit_intr_info;
+       u32 idt_vectoring_info;
        bool unblock_nmi;
        u8 vector;
+       int type;
+       bool idtv_info_valid;
 
        exit_intr_info = vmcs_read32(VM_EXIT_INTR_INFO);
        if (cpu_has_virtual_nmis()) {
@@ -2836,18 +2838,34 @@ static void vmx_complete_interrupts(struct vcpu_vmx *vmx)
                        vmcs_set_bits(GUEST_INTERRUPTIBILITY_INFO,
                                      GUEST_INTR_STATE_NMI);
        }
+
+       idt_vectoring_info = vmx->idt_vectoring_info;
+       idtv_info_valid = idt_vectoring_info & VECTORING_INFO_VALID_MASK;
+       vector = idt_vectoring_info & VECTORING_INFO_VECTOR_MASK;
+       type = idt_vectoring_info & VECTORING_INFO_TYPE_MASK;
+       if (vmx->vcpu.arch.nmi_injected) {
+               /*
+                * SDM 3: 25.7.1.2
+                * Clear bit "block by NMI" before VM entry if a NMI delivery
+                * faulted.
+                */
+               if (idtv_info_valid && type == INTR_TYPE_NMI_INTR)
+                       vmcs_clear_bits(GUEST_INTERRUPTIBILITY_INFO,
+                                       GUEST_INTR_STATE_NMI);
+               else
+                       vmx->vcpu.arch.nmi_injected = false;
+       }
 }
 
 static void vmx_intr_assist(struct kvm_vcpu *vcpu)
 {
        struct vcpu_vmx *vmx = to_vmx(vcpu);
-       u32 idtv_info_field, intr_info_field, exit_intr_info_field;
+       u32 idtv_info_field, intr_info_field;
        int vector;
 
        update_tpr_threshold(vcpu);
 
        intr_info_field = vmcs_read32(VM_ENTRY_INTR_INFO_FIELD);
-       exit_intr_info_field = vmcs_read32(VM_EXIT_INTR_INFO);
        idtv_info_field = vmx->idt_vectoring_info;
        if (intr_info_field & INTR_INFO_VALID_MASK) {
                if (idtv_info_field & INTR_INFO_VALID_MASK) {
@@ -2871,17 +2889,6 @@ static void vmx_intr_assist(struct kvm_vcpu *vcpu)
 
                KVMTRACE_1D(REDELIVER_EVT, vcpu, idtv_info_field, handler);
 
-               /*
-                * SDM 3: 25.7.1.2
-                * Clear bit "block by NMI" before VM entry if a NMI delivery
-                * faulted.
-                */
-               if ((idtv_info_field & VECTORING_INFO_TYPE_MASK)
-                   == INTR_TYPE_NMI_INTR && cpu_has_virtual_nmis())
-                       vmcs_write32(GUEST_INTERRUPTIBILITY_INFO,
-                               vmcs_read32(GUEST_INTERRUPTIBILITY_INFO) &
-                               ~GUEST_INTR_STATE_NMI);
-
                vmcs_write32(VM_ENTRY_INTR_INFO_FIELD, idtv_info_field
                                & ~INTR_INFO_RESVD_BITS_MASK);
                vmcs_write32(VM_ENTRY_INSTRUCTION_LEN,
@@ -2894,9 +2901,17 @@ static void vmx_intr_assist(struct kvm_vcpu *vcpu)
                return;
        }
        if (cpu_has_virtual_nmis()) {
-               if (vcpu->arch.nmi_pending) {
-                       if (vmx_nmi_enabled(vcpu))
-                               vmx_inject_nmi(vcpu);
+               if (vcpu->arch.nmi_pending && !vcpu->arch.nmi_injected) {
+                       if (vmx_nmi_enabled(vcpu)) {
+                               vcpu->arch.nmi_pending = false;
+                               vcpu->arch.nmi_injected = true;
+                       } else {
+                               enable_intr_window(vcpu);
+                               return;
+                       }
+               }
+               if (vcpu->arch.nmi_injected) {
+                       vmx_inject_nmi(vcpu);
                        enable_intr_window(vcpu);
                        return;
                }

diff --git a/include/asm-x86/kvm_host.h b/include/asm-x86/kvm_host.h
index 4f2bd884fd3a53b67a32d7b145a5375d3fa0a048..7cf69fd1dcfe99b4b058051005638c3c7ddad410 100644 (file)
--- a/include/asm-x86/kvm_host.h
+++ b/include/asm-x86/kvm_host.h
@@ -300,6 +300,7 @@ struct kvm_vcpu_arch {
        struct page *time_page;
 
        bool nmi_pending;
+       bool nmi_injected;
 
        u64 mtrr[0x100];
 };