x86, apicv: add virtual interrupt delivery support

Virtual interrupt delivery avoids KVM to inject vAPIC interrupts
manually, which is fully taken care of by the hardware. This needs
some special awareness into existing interrupr injection path:

- for pending interrupt, instead of direct injection, we may need
  update architecture specific indicators before resuming to guest.

- A pending interrupt, which is masked by ISR, should be also
  considered in above update action, since hardware will decide
  when to inject it at right time. Current has_interrupt and
  get_interrupt only returns a valid vector from injection p.o.v.
Reviewed-by: Marcelo Tosatti <mtosatti@redhat.com>
Signed-off-by: Kevin Tian <kevin.tian@intel.com>
Signed-off-by: Yang Zhang <yang.z.zhang@Intel.com>
Signed-off-by: Gleb Natapov <gleb@redhat.com>

arch/ia64/kvm/lapic.h

@@ -27,4 +27,10 @@ int kvm_apic_set_irq(struct kvm_vcpu *vcpu, struct kvm_lapic_irq *irq);
 #define kvm_apic_present(x) (true)
 #define kvm_lapic_enabled(x) (true)
 
+static inline bool kvm_apic_vid_enabled(void)
+{
+	/* IA64 has no apicv supporting, do nothing here */
+	return false;
+}
+
 #endif

arch/x86/include/asm/kvm_host.h

@@ -699,6 +699,10 @@ struct kvm_x86_ops {
 	void (*enable_nmi_window)(struct kvm_vcpu *vcpu);
 	void (*enable_irq_window)(struct kvm_vcpu *vcpu);
 	void (*update_cr8_intercept)(struct kvm_vcpu *vcpu, int tpr, int irr);
+	int (*vm_has_apicv)(struct kvm *kvm);
+	void (*hwapic_irr_update)(struct kvm_vcpu *vcpu, int max_irr);
+	void (*hwapic_isr_update)(struct kvm *kvm, int isr);
+	void (*load_eoi_exitmap)(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap);
 	void (*set_virtual_x2apic_mode)(struct kvm_vcpu *vcpu, bool set);
 	int (*set_tss_addr)(struct kvm *kvm, unsigned int addr);
 	int (*get_tdp_level)(void);
@@ -994,6 +998,7 @@ int kvm_age_hva(struct kvm *kvm, unsigned long hva);
 int kvm_test_age_hva(struct kvm *kvm, unsigned long hva);
 void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte);
 int cpuid_maxphyaddr(struct kvm_vcpu *vcpu);
+int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v);
 int kvm_cpu_has_interrupt(struct kvm_vcpu *vcpu);
 int kvm_arch_interrupt_allowed(struct kvm_vcpu *vcpu);
 int kvm_cpu_get_interrupt(struct kvm_vcpu *v);

arch/x86/include/asm/vmx.h

@@ -62,6 +62,7 @@
 #define EXIT_REASON_MCE_DURING_VMENTRY  41
 #define EXIT_REASON_TPR_BELOW_THRESHOLD 43
 #define EXIT_REASON_APIC_ACCESS         44
+#define EXIT_REASON_EOI_INDUCED         45
 #define EXIT_REASON_EPT_VIOLATION       48
 #define EXIT_REASON_EPT_MISCONFIG       49
 #define EXIT_REASON_WBINVD              54
@@ -144,6 +145,7 @@
 #define SECONDARY_EXEC_WBINVD_EXITING		0x00000040
 #define SECONDARY_EXEC_UNRESTRICTED_GUEST	0x00000080
 #define SECONDARY_EXEC_APIC_REGISTER_VIRT       0x00000100
+#define SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY    0x00000200
 #define SECONDARY_EXEC_PAUSE_LOOP_EXITING	0x00000400
 #define SECONDARY_EXEC_ENABLE_INVPCID		0x00001000
 
@@ -181,6 +183,7 @@ enum vmcs_field {
 	GUEST_GS_SELECTOR               = 0x0000080a,
 	GUEST_LDTR_SELECTOR             = 0x0000080c,
 	GUEST_TR_SELECTOR               = 0x0000080e,
+	GUEST_INTR_STATUS               = 0x00000810,
 	HOST_ES_SELECTOR                = 0x00000c00,
 	HOST_CS_SELECTOR                = 0x00000c02,
 	HOST_SS_SELECTOR                = 0x00000c04,
@@ -208,6 +211,14 @@ enum vmcs_field {
 	APIC_ACCESS_ADDR_HIGH		= 0x00002015,
 	EPT_POINTER                     = 0x0000201a,
 	EPT_POINTER_HIGH                = 0x0000201b,
+	EOI_EXIT_BITMAP0                = 0x0000201c,
+	EOI_EXIT_BITMAP0_HIGH           = 0x0000201d,
+	EOI_EXIT_BITMAP1                = 0x0000201e,
+	EOI_EXIT_BITMAP1_HIGH           = 0x0000201f,
+	EOI_EXIT_BITMAP2                = 0x00002020,
+	EOI_EXIT_BITMAP2_HIGH           = 0x00002021,
+	EOI_EXIT_BITMAP3                = 0x00002022,
+	EOI_EXIT_BITMAP3_HIGH           = 0x00002023,
 	GUEST_PHYSICAL_ADDRESS          = 0x00002400,
 	GUEST_PHYSICAL_ADDRESS_HIGH     = 0x00002401,
 	VMCS_LINK_POINTER               = 0x00002800,

arch/x86/kvm/irq.c

@@ -37,6 +37,38 @@ int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu)
 }
 EXPORT_SYMBOL(kvm_cpu_has_pending_timer);
 
+/*
+ * check if there is pending interrupt from
+ * non-APIC source without intack.
+ */
+static int kvm_cpu_has_extint(struct kvm_vcpu *v)
+{
+	if (kvm_apic_accept_pic_intr(v))
+		return pic_irqchip(v->kvm)->output;	/* PIC */
+	else
+		return 0;
+}
+
+/*
+ * check if there is injectable interrupt:
+ * when virtual interrupt delivery enabled,
+ * interrupt from apic will handled by hardware,
+ * we don't need to check it here.
+ */
+int kvm_cpu_has_injectable_intr(struct kvm_vcpu *v)
+{
+	if (!irqchip_in_kernel(v->kvm))
+		return v->arch.interrupt.pending;
+
+	if (kvm_cpu_has_extint(v))
+		return 1;
+
+	if (kvm_apic_vid_enabled(v->kvm))
+		return 0;
+
+	return kvm_apic_has_interrupt(v) != -1; /* LAPIC */
+}
+
 /*
  * check if there is pending interrupt without
  * intack.
@@ -46,27 +78,41 @@ int kvm_cpu_has_interrupt(struct kvm_vcpu *v)
 	if (!irqchip_in_kernel(v->kvm))
 		return v->arch.interrupt.pending;
 
-	if (kvm_apic_accept_pic_intr(v) && pic_irqchip(v->kvm)->output)
-		return pic_irqchip(v->kvm)->output;	/* PIC */
+	if (kvm_cpu_has_extint(v))
+		return 1;
 
 	return kvm_apic_has_interrupt(v) != -1;	/* LAPIC */
 }
 EXPORT_SYMBOL_GPL(kvm_cpu_has_interrupt);
 
+/*
+ * Read pending interrupt(from non-APIC source)
+ * vector and intack.
+ */
+static int kvm_cpu_get_extint(struct kvm_vcpu *v)
+{
+	if (kvm_cpu_has_extint(v))
+		return kvm_pic_read_irq(v->kvm); /* PIC */
+	return -1;
+}
+
 /*
  * Read pending interrupt vector and intack.
  */
 int kvm_cpu_get_interrupt(struct kvm_vcpu *v)
 {
+	int vector;
+
 	if (!irqchip_in_kernel(v->kvm))
 		return v->arch.interrupt.nr;
 
-	if (kvm_apic_accept_pic_intr(v) && pic_irqchip(v->kvm)->output)
-		return kvm_pic_read_irq(v->kvm);	/* PIC */
+	vector = kvm_cpu_get_extint(v);
+
+	if (kvm_apic_vid_enabled(v->kvm) || vector != -1)
+		return vector;			/* PIC */
 
 	return kvm_get_apic_interrupt(v);	/* APIC */
 }
-EXPORT_SYMBOL_GPL(kvm_cpu_get_interrupt);
 
 void kvm_inject_pending_timer_irqs(struct kvm_vcpu *vcpu)
 {

arch/x86/kvm/lapic.c

@@ -145,21 +145,51 @@ static inline int kvm_apic_id(struct kvm_lapic *apic)
 	return (kvm_apic_get_reg(apic, APIC_ID) >> 24) & 0xff;
 }
 
-static inline u16 apic_cluster_id(struct kvm_apic_map *map, u32 ldr)
+void kvm_calculate_eoi_exitmap(struct kvm_vcpu *vcpu,
+				struct kvm_lapic_irq *irq,
+				u64 *eoi_exit_bitmap)
 {
-	u16 cid;
-	ldr >>= 32 - map->ldr_bits;
-	cid = (ldr >> map->cid_shift) & map->cid_mask;
+	struct kvm_lapic **dst;
+	struct kvm_apic_map *map;
+	unsigned long bitmap = 1;
+	int i;
 
-	BUG_ON(cid >= ARRAY_SIZE(map->logical_map));
+	rcu_read_lock();
+	map = rcu_dereference(vcpu->kvm->arch.apic_map);
 
-	return cid;
-}
+	if (unlikely(!map)) {
+		__set_bit(irq->vector, (unsigned long *)eoi_exit_bitmap);
+		goto out;
+	}
 
-static inline u16 apic_logical_id(struct kvm_apic_map *map, u32 ldr)
-{
-	ldr >>= (32 - map->ldr_bits);
-	return ldr & map->lid_mask;
+	if (irq->dest_mode == 0) { /* physical mode */
+		if (irq->delivery_mode == APIC_DM_LOWEST ||
+				irq->dest_id == 0xff) {
+			__set_bit(irq->vector,
+				  (unsigned long *)eoi_exit_bitmap);
+			goto out;
+		}
+		dst = &map->phys_map[irq->dest_id & 0xff];
+	} else {
+		u32 mda = irq->dest_id << (32 - map->ldr_bits);
+
+		dst = map->logical_map[apic_cluster_id(map, mda)];
+
+		bitmap = apic_logical_id(map, mda);
+	}
+
+	for_each_set_bit(i, &bitmap, 16) {
+		if (!dst[i])
+			continue;
+		if (dst[i]->vcpu == vcpu) {
+			__set_bit(irq->vector,
+				  (unsigned long *)eoi_exit_bitmap);
+			break;
+		}
+	}
+
+out:
+	rcu_read_unlock();
 }
 
 static void recalculate_apic_map(struct kvm *kvm)
@@ -225,6 +255,8 @@ static void recalculate_apic_map(struct kvm *kvm)
 
 	if (old)
 		kfree_rcu(old, rcu);
+
+	kvm_ioapic_make_eoibitmap_request(kvm);
 }
 
 static inline void kvm_apic_set_id(struct kvm_lapic *apic, u8 id)
@@ -340,6 +372,10 @@ static inline int apic_find_highest_irr(struct kvm_lapic *apic)
 {
 	int result;
 
+	/*
+	 * Note that irr_pending is just a hint. It will be always
+	 * true with virtual interrupt delivery enabled.
+	 */
 	if (!apic->irr_pending)
 		return -1;
 
@@ -456,6 +492,8 @@ static void pv_eoi_clr_pending(struct kvm_vcpu *vcpu)
 static inline int apic_find_highest_isr(struct kvm_lapic *apic)
 {
 	int result;
+
+	/* Note that isr_count is always 1 with vid enabled */
 	if (!apic->isr_count)
 		return -1;
 	if (likely(apic->highest_isr_cache != -1))
@@ -735,6 +773,19 @@ int kvm_apic_compare_prio(struct kvm_vcpu *vcpu1, struct kvm_vcpu *vcpu2)
 	return vcpu1->arch.apic_arb_prio - vcpu2->arch.apic_arb_prio;
 }
 
+static void kvm_ioapic_send_eoi(struct kvm_lapic *apic, int vector)
+{
+	if (!(kvm_apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI) &&
+	    kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
+		int trigger_mode;
+		if (apic_test_vector(vector, apic->regs + APIC_TMR))
+			trigger_mode = IOAPIC_LEVEL_TRIG;
+		else
+			trigger_mode = IOAPIC_EDGE_TRIG;
+		kvm_ioapic_update_eoi(apic->vcpu->kvm, vector, trigger_mode);
+	}
+}
+
 static int apic_set_eoi(struct kvm_lapic *apic)
 {
 	int vector = apic_find_highest_isr(apic);
@@ -751,19 +802,26 @@ static int apic_set_eoi(struct kvm_lapic *apic)
 	apic_clear_isr(vector, apic);
 	apic_update_ppr(apic);
 
-	if (!(kvm_apic_get_reg(apic, APIC_SPIV) & APIC_SPIV_DIRECTED_EOI) &&
-	    kvm_ioapic_handles_vector(apic->vcpu->kvm, vector)) {
-		int trigger_mode;
-		if (apic_test_vector(vector, apic->regs + APIC_TMR))
-			trigger_mode = IOAPIC_LEVEL_TRIG;
-		else
-			trigger_mode = IOAPIC_EDGE_TRIG;
-		kvm_ioapic_update_eoi(apic->vcpu->kvm, vector, trigger_mode);
-	}
+	kvm_ioapic_send_eoi(apic, vector);
 	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
 	return vector;
 }
 
+/*
+ * this interface assumes a trap-like exit, which has already finished
+ * desired side effect including vISR and vPPR update.
+ */
+void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector)
+{
+	struct kvm_lapic *apic = vcpu->arch.apic;
+
+	trace_kvm_eoi(apic, vector);
+
+	kvm_ioapic_send_eoi(apic, vector);
+	kvm_make_request(KVM_REQ_EVENT, apic->vcpu);
+}
+EXPORT_SYMBOL_GPL(kvm_apic_set_eoi_accelerated);
+
 static void apic_send_ipi(struct kvm_lapic *apic)
 {
 	u32 icr_low = kvm_apic_get_reg(apic, APIC_ICR);
@@ -1375,8 +1433,8 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu)
 		apic_set_reg(apic, APIC_ISR + 0x10 * i, 0);
 		apic_set_reg(apic, APIC_TMR + 0x10 * i, 0);
 	}
-	apic->irr_pending = false;
-	apic->isr_count = 0;
+	apic->irr_pending = kvm_apic_vid_enabled(vcpu->kvm);
+	apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm);
 	apic->highest_isr_cache = -1;
 	update_divide_count(apic);
 	atomic_set(&apic->lapic_timer.pending, 0);
@@ -1591,8 +1649,10 @@ void kvm_apic_post_state_restore(struct kvm_vcpu *vcpu,
 	update_divide_count(apic);
 	start_apic_timer(apic);
 	apic->irr_pending = true;
-	apic->isr_count = count_vectors(apic->regs + APIC_ISR);
+	apic->isr_count = kvm_apic_vid_enabled(vcpu->kvm) ?
+				1 : count_vectors(apic->regs + APIC_ISR);
 	apic->highest_isr_cache = -1;
+	kvm_x86_ops->hwapic_isr_update(vcpu->kvm, apic_find_highest_isr(apic));
 	kvm_make_request(KVM_REQ_EVENT, vcpu);
 }
 

arch/x86/kvm/lapic.h

@@ -65,6 +65,7 @@ u64 kvm_get_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu);
 void kvm_set_lapic_tscdeadline_msr(struct kvm_vcpu *vcpu, u64 data);
 
 void kvm_apic_write_nodecode(struct kvm_vcpu *vcpu, u32 offset);
+void kvm_apic_set_eoi_accelerated(struct kvm_vcpu *vcpu, int vector);
 
 void kvm_lapic_set_vapic_addr(struct kvm_vcpu *vcpu, gpa_t vapic_addr);
 void kvm_lapic_sync_from_vapic(struct kvm_vcpu *vcpu);
@@ -131,4 +132,30 @@ static inline int apic_x2apic_mode(struct kvm_lapic *apic)
 	return apic->vcpu->arch.apic_base & X2APIC_ENABLE;
 }
 
+static inline bool kvm_apic_vid_enabled(struct kvm *kvm)
+{
+	return kvm_x86_ops->vm_has_apicv(kvm);
+}
+
+static inline u16 apic_cluster_id(struct kvm_apic_map *map, u32 ldr)
+{
+	u16 cid;
+	ldr >>= 32 - map->ldr_bits;
+	cid = (ldr >> map->cid_shift) & map->cid_mask;
+
+	BUG_ON(cid >= ARRAY_SIZE(map->logical_map));
+
+	return cid;
+}
+
+static inline u16 apic_logical_id(struct kvm_apic_map *map, u32 ldr)
+{
+	ldr >>= (32 - map->ldr_bits);
+	return ldr & map->lid_mask;
+}
+
+void kvm_calculate_eoi_exitmap(struct kvm_vcpu *vcpu,
+				struct kvm_lapic_irq *irq,
+				u64 *eoi_bitmap);
+
 #endif

arch/x86/kvm/svm.c

@@ -3576,6 +3576,21 @@ static void svm_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
 	return;
 }
 
+static int svm_vm_has_apicv(struct kvm *kvm)
+{
+	return 0;
+}
+
+static void svm_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+{
+	return;
+}
+
+static void svm_hwapic_isr_update(struct kvm *kvm, int isr)
+{
+	return;
+}
+
 static int svm_nmi_allowed(struct kvm_vcpu *vcpu)
 {
 	struct vcpu_svm *svm = to_svm(vcpu);
@@ -4296,6 +4311,9 @@ static struct kvm_x86_ops svm_x86_ops = {
 	.enable_irq_window = enable_irq_window,
 	.update_cr8_intercept = update_cr8_intercept,
 	.set_virtual_x2apic_mode = svm_set_virtual_x2apic_mode,
+	.vm_has_apicv = svm_vm_has_apicv,
+	.load_eoi_exitmap = svm_load_eoi_exitmap,
+	.hwapic_isr_update = svm_hwapic_isr_update,
 
 	.set_tss_addr = svm_set_tss_addr,
 	.get_tdp_level = get_npt_level,

arch/x86/kvm/vmx.c

@@ -84,8 +84,8 @@ module_param(vmm_exclusive, bool, S_IRUGO);
 static bool __read_mostly fasteoi = 1;
 module_param(fasteoi, bool, S_IRUGO);
 
-static bool __read_mostly enable_apicv_reg = 1;
-module_param(enable_apicv_reg, bool, S_IRUGO);
+static bool __read_mostly enable_apicv_reg_vid = 1;
+module_param(enable_apicv_reg_vid, bool, S_IRUGO);
 
 /*
  * If nested=1, nested virtualization is supported, i.e., guests may use
@@ -781,6 +781,12 @@ static inline bool cpu_has_vmx_apic_register_virt(void)
 		SECONDARY_EXEC_APIC_REGISTER_VIRT;
 }
 
+static inline bool cpu_has_vmx_virtual_intr_delivery(void)
+{
+	return vmcs_config.cpu_based_2nd_exec_ctrl &
+		SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY;
+}
+
 static inline bool cpu_has_vmx_flexpriority(void)
 {
 	return cpu_has_vmx_tpr_shadow() &&
@@ -2571,7 +2577,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf)
 			SECONDARY_EXEC_PAUSE_LOOP_EXITING |
 			SECONDARY_EXEC_RDTSCP |
 			SECONDARY_EXEC_ENABLE_INVPCID |
-			SECONDARY_EXEC_APIC_REGISTER_VIRT;
+			SECONDARY_EXEC_APIC_REGISTER_VIRT |
+			SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY;
 		if (adjust_vmx_controls(min2, opt2,
 					MSR_IA32_VMX_PROCBASED_CTLS2,
 					&_cpu_based_2nd_exec_control) < 0)
@@ -2586,7 +2593,8 @@ static __init int setup_vmcs_config(struct vmcs_config *vmcs_conf)
 	if (!(_cpu_based_exec_control & CPU_BASED_TPR_SHADOW))
 		_cpu_based_2nd_exec_control &= ~(
 				SECONDARY_EXEC_APIC_REGISTER_VIRT |
-				SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE);
+				SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE |
+				SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
 
 	if (_cpu_based_2nd_exec_control & SECONDARY_EXEC_ENABLE_EPT) {
 		/* CR3 accesses and invlpg don't need to cause VM Exits when EPT
@@ -2785,8 +2793,14 @@ static __init int hardware_setup(void)
 	if (!cpu_has_vmx_ple())
 		ple_gap = 0;
 
-	if (!cpu_has_vmx_apic_register_virt())
-		enable_apicv_reg = 0;
+	if (!cpu_has_vmx_apic_register_virt() ||
+				!cpu_has_vmx_virtual_intr_delivery())
+		enable_apicv_reg_vid = 0;
+
+	if (enable_apicv_reg_vid)
+		kvm_x86_ops->update_cr8_intercept = NULL;
+	else
+		kvm_x86_ops->hwapic_irr_update = NULL;
 
 	if (nested)
 		nested_vmx_setup_ctls_msrs();
@@ -3928,6 +3942,11 @@ static u32 vmx_exec_control(struct vcpu_vmx *vmx)
 	return exec_control;
 }
 
+static int vmx_vm_has_apicv(struct kvm *kvm)
+{
+	return enable_apicv_reg_vid && irqchip_in_kernel(kvm);
+}
+
 static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
 {
 	u32 exec_control = vmcs_config.cpu_based_2nd_exec_ctrl;
@@ -3945,8 +3964,9 @@ static u32 vmx_secondary_exec_control(struct vcpu_vmx *vmx)
 		exec_control &= ~SECONDARY_EXEC_UNRESTRICTED_GUEST;
 	if (!ple_gap)
 		exec_control &= ~SECONDARY_EXEC_PAUSE_LOOP_EXITING;
-	if (!enable_apicv_reg || !irqchip_in_kernel(vmx->vcpu.kvm))
-		exec_control &= ~SECONDARY_EXEC_APIC_REGISTER_VIRT;
+	if (!vmx_vm_has_apicv(vmx->vcpu.kvm))
+		exec_control &= ~(SECONDARY_EXEC_APIC_REGISTER_VIRT |
+				  SECONDARY_EXEC_VIRTUAL_INTR_DELIVERY);
 	exec_control &= ~SECONDARY_EXEC_VIRTUALIZE_X2APIC_MODE;
 	return exec_control;
 }
@@ -3992,6 +4012,15 @@ static int vmx_vcpu_setup(struct vcpu_vmx *vmx)
 				vmx_secondary_exec_control(vmx));
 	}
 
+	if (enable_apicv_reg_vid) {
+		vmcs_write64(EOI_EXIT_BITMAP0, 0);
+		vmcs_write64(EOI_EXIT_BITMAP1, 0);
+		vmcs_write64(EOI_EXIT_BITMAP2, 0);
+		vmcs_write64(EOI_EXIT_BITMAP3, 0);
+
+		vmcs_write16(GUEST_INTR_STATUS, 0);
+	}
+
 	if (ple_gap) {
 		vmcs_write32(PLE_GAP, ple_gap);
 		vmcs_write32(PLE_WINDOW, ple_window);
@@ -4906,6 +4935,16 @@ static int handle_apic_access(struct kvm_vcpu *vcpu)
 	return emulate_instruction(vcpu, 0) == EMULATE_DONE;
 }
 
+static int handle_apic_eoi_induced(struct kvm_vcpu *vcpu)
+{
+	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
+	int vector = exit_qualification & 0xff;
+
+	/* EOI-induced VM exit is trap-like and thus no need to adjust IP */
+	kvm_apic_set_eoi_accelerated(vcpu, vector);
+	return 1;
+}
+
 static int handle_apic_write(struct kvm_vcpu *vcpu)
 {
 	unsigned long exit_qualification = vmcs_readl(EXIT_QUALIFICATION);
@@ -5851,6 +5890,7 @@ static int (*const kvm_vmx_exit_handlers[])(struct kvm_vcpu *vcpu) = {
 	[EXIT_REASON_TPR_BELOW_THRESHOLD]     = handle_tpr_below_threshold,
 	[EXIT_REASON_APIC_ACCESS]             = handle_apic_access,
 	[EXIT_REASON_APIC_WRITE]              = handle_apic_write,
+	[EXIT_REASON_EOI_INDUCED]             = handle_apic_eoi_induced,
 	[EXIT_REASON_WBINVD]                  = handle_wbinvd,
 	[EXIT_REASON_XSETBV]                  = handle_xsetbv,
 	[EXIT_REASON_TASK_SWITCH]             = handle_task_switch,
@@ -6208,7 +6248,8 @@ static void vmx_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
 	 * There is not point to enable virtualize x2apic without enable
 	 * apicv
 	 */
-	if (!cpu_has_vmx_virtualize_x2apic_mode() || !enable_apicv_reg)
+	if (!cpu_has_vmx_virtualize_x2apic_mode() ||
+				!vmx_vm_has_apicv(vcpu->kvm))
 		return;
 
 	if (!vm_need_tpr_shadow(vcpu->kvm))
@@ -6228,6 +6269,56 @@ static void vmx_set_virtual_x2apic_mode(struct kvm_vcpu *vcpu, bool set)
 	vmx_set_msr_bitmap(vcpu);
 }
 
+static void vmx_hwapic_isr_update(struct kvm *kvm, int isr)
+{
+	u16 status;
+	u8 old;
+
+	if (!vmx_vm_has_apicv(kvm))
+		return;
+
+	if (isr == -1)
+		isr = 0;
+
+	status = vmcs_read16(GUEST_INTR_STATUS);
+	old = status >> 8;
+	if (isr != old) {
+		status &= 0xff;
+		status |= isr << 8;
+		vmcs_write16(GUEST_INTR_STATUS, status);
+	}
+}
+
+static void vmx_set_rvi(int vector)
+{
+	u16 status;
+	u8 old;
+
+	status = vmcs_read16(GUEST_INTR_STATUS);
+	old = (u8)status & 0xff;
+	if ((u8)vector != old) {
+		status &= ~0xff;
+		status |= (u8)vector;
+		vmcs_write16(GUEST_INTR_STATUS, status);
+	}
+}
+
+static void vmx_hwapic_irr_update(struct kvm_vcpu *vcpu, int max_irr)
+{
+	if (max_irr == -1)
+		return;
+
+	vmx_set_rvi(max_irr);
+}
+
+static void vmx_load_eoi_exitmap(struct kvm_vcpu *vcpu, u64 *eoi_exit_bitmap)
+{
+	vmcs_write64(EOI_EXIT_BITMAP0, eoi_exit_bitmap[0]);
+	vmcs_write64(EOI_EXIT_BITMAP1, eoi_exit_bitmap[1]);
+	vmcs_write64(EOI_EXIT_BITMAP2, eoi_exit_bitmap[2]);
+	vmcs_write64(EOI_EXIT_BITMAP3, eoi_exit_bitmap[3]);
+}
+
 static void vmx_complete_atomic_exit(struct vcpu_vmx *vmx)
 {
 	u32 exit_intr_info;
@@ -7492,6 +7583,10 @@ static struct kvm_x86_ops vmx_x86_ops = {
 	.enable_irq_window = enable_irq_window,
 	.update_cr8_intercept = update_cr8_intercept,
 	.set_virtual_x2apic_mode = vmx_set_virtual_x2apic_mode,
+	.vm_has_apicv = vmx_vm_has_apicv,
+	.load_eoi_exitmap = vmx_load_eoi_exitmap,
+	.hwapic_irr_update = vmx_hwapic_irr_update,
+	.hwapic_isr_update = vmx_hwapic_isr_update,
 
 	.set_tss_addr = vmx_set_tss_addr,
 	.get_tdp_level = get_ept_level,
@@ -7594,7 +7689,7 @@ static int __init vmx_init(void)
 	memcpy(vmx_msr_bitmap_longmode_x2apic,
 			vmx_msr_bitmap_longmode, PAGE_SIZE);
 
-	if (enable_apicv_reg) {
+	if (enable_apicv_reg_vid) {
 		for (msr = 0x800; msr <= 0x8ff; msr++)
 			vmx_disable_intercept_msr_read_x2apic(msr);
 
@@ -7606,6 +7701,10 @@ static int __init vmx_init(void)
 		vmx_enable_intercept_msr_read_x2apic(0x839);
 		/* TPR */
 		vmx_disable_intercept_msr_write_x2apic(0x808);
+		/* EOI */
+		vmx_disable_intercept_msr_write_x2apic(0x80b);
+		/* SELF-IPI */
+		vmx_disable_intercept_msr_write_x2apic(0x83f);
 	}
 
 	if (enable_ept) {

arch/x86/kvm/x86.c

@@ -5565,7 +5565,7 @@ static void inject_pending_event(struct kvm_vcpu *vcpu)
 			vcpu->arch.nmi_injected = true;
 			kvm_x86_ops->set_nmi(vcpu);
 		}
-	} else if (kvm_cpu_has_interrupt(vcpu)) {
+	} else if (kvm_cpu_has_injectable_intr(vcpu)) {
 		if (kvm_x86_ops->interrupt_allowed(vcpu)) {
 			kvm_queue_interrupt(vcpu, kvm_cpu_get_interrupt(vcpu),
 					    false);
@@ -5633,6 +5633,16 @@ static void kvm_gen_update_masterclock(struct kvm *kvm)
 #endif
 }
 
+static void update_eoi_exitmap(struct kvm_vcpu *vcpu)
+{
+	u64 eoi_exit_bitmap[4];
+
+	memset(eoi_exit_bitmap, 0, 32);
+
+	kvm_ioapic_calculate_eoi_exitmap(vcpu, eoi_exit_bitmap);
+	kvm_x86_ops->load_eoi_exitmap(vcpu, eoi_exit_bitmap);
+}
+
 static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 {
 	int r;
@@ -5686,6 +5696,8 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 			kvm_handle_pmu_event(vcpu);
 		if (kvm_check_request(KVM_REQ_PMI, vcpu))
 			kvm_deliver_pmi(vcpu);
+		if (kvm_check_request(KVM_REQ_EOIBITMAP, vcpu))
+			update_eoi_exitmap(vcpu);
 	}
 
 	if (kvm_check_request(KVM_REQ_EVENT, vcpu) || req_int_win) {
@@ -5694,10 +5706,17 @@ static int vcpu_enter_guest(struct kvm_vcpu *vcpu)
 		/* enable NMI/IRQ window open exits if needed */
 		if (vcpu->arch.nmi_pending)
 			kvm_x86_ops->enable_nmi_window(vcpu);
-		else if (kvm_cpu_has_interrupt(vcpu) || req_int_win)
+		else if (kvm_cpu_has_injectable_intr(vcpu) || req_int_win)
 			kvm_x86_ops->enable_irq_window(vcpu);
 
 		if (kvm_lapic_enabled(vcpu)) {
+			/*
+			 * Update architecture specific hints for APIC
+			 * virtual interrupt delivery.
+			 */
+			if (kvm_x86_ops->hwapic_irr_update)
+				kvm_x86_ops->hwapic_irr_update(vcpu,
+					kvm_lapic_find_highest_irr(vcpu));
 			update_cr8_intercept(vcpu);
 			kvm_lapic_sync_to_vapic(vcpu);
 		}

include/linux/kvm_host.h

@@ -123,6 +123,7 @@ static inline bool is_error_page(struct page *page)
 #define KVM_REQ_MASTERCLOCK_UPDATE 19
 #define KVM_REQ_MCLOCK_INPROGRESS 20
 #define KVM_REQ_EPR_EXIT          21
+#define KVM_REQ_EOIBITMAP         22
 
 #define KVM_USERSPACE_IRQ_SOURCE_ID		0
 #define KVM_IRQFD_RESAMPLE_IRQ_SOURCE_ID	1
@@ -538,6 +539,7 @@ void kvm_put_guest_fpu(struct kvm_vcpu *vcpu);
 void kvm_flush_remote_tlbs(struct kvm *kvm);
 void kvm_reload_remote_mmus(struct kvm *kvm);
 void kvm_make_mclock_inprogress_request(struct kvm *kvm);
+void kvm_make_update_eoibitmap_request(struct kvm *kvm);
 
 long kvm_arch_dev_ioctl(struct file *filp,
 			unsigned int ioctl, unsigned long arg);
@@ -691,6 +693,7 @@ int kvm_set_irq(struct kvm *kvm, int irq_source_id, u32 irq, int level);
 int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level);
 int kvm_set_msi(struct kvm_kernel_irq_routing_entry *irq_entry, struct kvm *kvm,
 		int irq_source_id, int level);
+bool kvm_irq_has_notifier(struct kvm *kvm, unsigned irqchip, unsigned pin);
 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin);
 void kvm_register_irq_ack_notifier(struct kvm *kvm,
 				   struct kvm_irq_ack_notifier *kian);

virt/kvm/ioapic.c

@@ -35,6 +35,7 @@
 #include <linux/hrtimer.h>
 #include <linux/io.h>
 #include <linux/slab.h>
+#include <linux/export.h>
 #include <asm/processor.h>
 #include <asm/page.h>
 #include <asm/current.h>
@@ -115,6 +116,42 @@ static void update_handled_vectors(struct kvm_ioapic *ioapic)
 	smp_wmb();
 }
 
+void kvm_ioapic_calculate_eoi_exitmap(struct kvm_vcpu *vcpu,
+					u64 *eoi_exit_bitmap)
+{
+	struct kvm_ioapic *ioapic = vcpu->kvm->arch.vioapic;
+	union kvm_ioapic_redirect_entry *e;
+	struct kvm_lapic_irq irqe;
+	int index;
+
+	spin_lock(&ioapic->lock);
+	/* traverse ioapic entry to set eoi exit bitmap*/
+	for (index = 0; index < IOAPIC_NUM_PINS; index++) {
+		e = &ioapic->redirtbl[index];
+		if (!e->fields.mask &&
+			(e->fields.trig_mode == IOAPIC_LEVEL_TRIG ||
+			 kvm_irq_has_notifier(ioapic->kvm, KVM_IRQCHIP_IOAPIC,
+				 index))) {
+			irqe.dest_id = e->fields.dest_id;
+			irqe.vector = e->fields.vector;
+			irqe.dest_mode = e->fields.dest_mode;
+			irqe.delivery_mode = e->fields.delivery_mode << 8;
+			kvm_calculate_eoi_exitmap(vcpu, &irqe, eoi_exit_bitmap);
+		}
+	}
+	spin_unlock(&ioapic->lock);
+}
+EXPORT_SYMBOL_GPL(kvm_ioapic_calculate_eoi_exitmap);
+
+void kvm_ioapic_make_eoibitmap_request(struct kvm *kvm)
+{
+	struct kvm_ioapic *ioapic = kvm->arch.vioapic;
+
+	if (!kvm_apic_vid_enabled(kvm) || !ioapic)
+		return;
+	kvm_make_update_eoibitmap_request(kvm);
+}
+
 static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 {
 	unsigned index;
@@ -156,6 +193,7 @@ static void ioapic_write_indirect(struct kvm_ioapic *ioapic, u32 val)
 		if (e->fields.trig_mode == IOAPIC_LEVEL_TRIG
 		    && ioapic->irr & (1 << index))
 			ioapic_service(ioapic, index);
+		kvm_ioapic_make_eoibitmap_request(ioapic->kvm);
 		break;
 	}
 }
@@ -455,6 +493,7 @@ int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state)
 	spin_lock(&ioapic->lock);
 	memcpy(ioapic, state, sizeof(struct kvm_ioapic_state));
 	update_handled_vectors(ioapic);
+	kvm_ioapic_make_eoibitmap_request(kvm);
 	spin_unlock(&ioapic->lock);
 	return 0;
 }

virt/kvm/ioapic.h

@@ -82,5 +82,9 @@ int kvm_irq_delivery_to_apic(struct kvm *kvm, struct kvm_lapic *src,
 		struct kvm_lapic_irq *irq);
 int kvm_get_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
 int kvm_set_ioapic(struct kvm *kvm, struct kvm_ioapic_state *state);
+void kvm_ioapic_make_eoibitmap_request(struct kvm *kvm);
+void kvm_ioapic_calculate_eoi_exitmap(struct kvm_vcpu *vcpu,
+					u64 *eoi_exit_bitmap);
+
 
 #endif

virt/kvm/irq_comm.c

@@ -22,6 +22,7 @@
 
 #include <linux/kvm_host.h>
 #include <linux/slab.h>
+#include <linux/export.h>
 #include <trace/events/kvm.h>
 
 #include <asm/msidef.h>
@@ -237,6 +238,28 @@ int kvm_set_irq_inatomic(struct kvm *kvm, int irq_source_id, u32 irq, int level)
 	return ret;
 }
 
+bool kvm_irq_has_notifier(struct kvm *kvm, unsigned irqchip, unsigned pin)
+{
+	struct kvm_irq_ack_notifier *kian;
+	struct hlist_node *n;
+	int gsi;
+
+	rcu_read_lock();
+	gsi = rcu_dereference(kvm->irq_routing)->chip[irqchip][pin];
+	if (gsi != -1)
+		hlist_for_each_entry_rcu(kian, n, &kvm->irq_ack_notifier_list,
+					 link)
+			if (kian->gsi == gsi) {
+				rcu_read_unlock();
+				return true;
+			}
+
+	rcu_read_unlock();
+
+	return false;
+}
+EXPORT_SYMBOL_GPL(kvm_irq_has_notifier);
+
 void kvm_notify_acked_irq(struct kvm *kvm, unsigned irqchip, unsigned pin)
 {
 	struct kvm_irq_ack_notifier *kian;
@@ -261,6 +284,7 @@ void kvm_register_irq_ack_notifier(struct kvm *kvm,
 	mutex_lock(&kvm->irq_lock);
 	hlist_add_head_rcu(&kian->link, &kvm->irq_ack_notifier_list);
 	mutex_unlock(&kvm->irq_lock);
+	kvm_ioapic_make_eoibitmap_request(kvm);
 }
 
 void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
@@ -270,6 +294,7 @@ void kvm_unregister_irq_ack_notifier(struct kvm *kvm,
 	hlist_del_init_rcu(&kian->link);
 	mutex_unlock(&kvm->irq_lock);
 	synchronize_rcu();
+	kvm_ioapic_make_eoibitmap_request(kvm);
 }
 
 int kvm_request_irq_source_id(struct kvm *kvm)

virt/kvm/kvm_main.c

@@ -217,6 +217,11 @@ void kvm_make_mclock_inprogress_request(struct kvm *kvm)
 	make_all_cpus_request(kvm, KVM_REQ_MCLOCK_INPROGRESS);
 }
 
+void kvm_make_update_eoibitmap_request(struct kvm *kvm)
+{
+	make_all_cpus_request(kvm, KVM_REQ_EOIBITMAP);
+}
+
 int kvm_vcpu_init(struct kvm_vcpu *vcpu, struct kvm *kvm, unsigned id)
 {
 	struct page *page;