[PATCH v4 5/6] KVM: X86: Add NMI support to PV IPIs

[Wanpeng Li <kernellwp@xxxxxxxxx>]

From: Wanpeng Li <wanpengli@xxxxxxxxxxx>

The NMI delivery mode of ICR is used to deliver an NMI to the processor, 
and the vector information is ignored.

Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
Cc: Radim Krčmář <rkrcmar@xxxxxxxxxx>
Cc: Vitaly Kuznetsov <vkuznets@xxxxxxxxxx>
Signed-off-by: Wanpeng Li <wanpengli@xxxxxxxxxxx>
---
 arch/x86/kernel/kvm.c | 15 ++++++++++++---
 arch/x86/kvm/x86.c    | 16 +++++++++++-----
 2 files changed, 23 insertions(+), 8 deletions(-)

diff --git a/arch/x86/kernel/kvm.c b/arch/x86/kernel/kvm.c
index 57eb4a2..3456531 100644
--- a/arch/x86/kernel/kvm.c
+++ b/arch/x86/kernel/kvm.c
@@ -458,7 +458,7 @@ static void __init sev_map_percpu_data(void)
 static int __send_ipi_mask(const struct cpumask *mask, int vector)
 {
 	unsigned long flags;
-	int cpu, apic_id, min = 0, max = 0, ret = 0;
+	int cpu, apic_id, min = 0, max = 0, ret = 0, icr = 0;
 #ifdef CONFIG_X86_64
 	__uint128_t ipi_bitmap = 0;
 	int cluster_size = 128;
@@ -472,6 +472,15 @@ static int __send_ipi_mask(const struct cpumask *mask, int vector)
 
 	local_irq_save(flags);
 
+	switch (vector) {
+	default:
+		icr = APIC_DM_FIXED | vector;
+		break;
+	case NMI_VECTOR:
+		icr = APIC_DM_NMI;
+		break;
+	}
+
 	for_each_cpu(cpu, mask) {
 		apic_id = per_cpu(x86_cpu_to_apicid, cpu);
 		if (!ipi_bitmap) {
@@ -483,7 +492,7 @@ static int __send_ipi_mask(const struct cpumask *mask, int vector)
 			max = apic_id < max ? max : apic_id;
 		} else {
 			ret = kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap,
-				(unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, vector);
+				(unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, icr);
 			min = max = apic_id;
 			ipi_bitmap = 0;
 		}
@@ -492,7 +501,7 @@ static int __send_ipi_mask(const struct cpumask *mask, int vector)
 
 	if (ipi_bitmap) {
 		ret = kvm_hypercall4(KVM_HC_SEND_IPI, (unsigned long)ipi_bitmap,
-			(unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, vector);
+			(unsigned long)(ipi_bitmap >> BITS_PER_LONG), min, icr);
 	}
 
 	local_irq_restore(flags);
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 016c7e2..c9dbc2c 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -6695,15 +6695,21 @@ static void kvm_pv_kick_cpu_op(struct kvm *kvm, unsigned long flags, int apicid)
  * Return 0 if successfully added and 1 if discarded.
  */
 static int kvm_pv_send_ipi(struct kvm *kvm, unsigned long ipi_bitmap_low,
-		unsigned long ipi_bitmap_high, int min, int vector, int op_64_bit)
+		unsigned long ipi_bitmap_high, int min, unsigned long icr, int op_64_bit)
 {
 	int i;
 	struct kvm_apic_map *map;
 	struct kvm_vcpu *vcpu;
-	struct kvm_lapic_irq irq = {
-		.delivery_mode = APIC_DM_FIXED,
-		.vector = vector,
-	};
+	struct kvm_lapic_irq irq = {0};
+
+	switch (icr & APIC_VECTOR_MASK) {
+	default:
+		irq.vector = icr & APIC_VECTOR_MASK;
+		break;
+	case NMI_VECTOR:
+		break;
+	}
+	irq.delivery_mode = icr & APIC_MODE_MASK;
 
 	rcu_read_lock();
 	map = rcu_dereference(kvm->arch.apic_map);
-- 
2.7.4