[RFC PATCH v7 14/28] KVM: arm64: Add SPE VCPU device attribute to initialize SPE

@@ -317,6 +317,7 @@ From the destination VMM process:
 Returns:
 
 	 =======  ==========================================================
+	 -EBUSY   SPE already initialized
 	 -EFAULT  Error accessing the buffer management interrupt number
 	 -EINVAL  Invalid interrupt number or not using an in-kernel irqchip
 	 -ENODEV  KVM_ARM_VCPU_HAS_SPE VCPU feature not set

@@ -338,15 +339,15 @@ vGIC implementation.
 
 :Returns:
 
-	 =======  =========================================================
-	 -EBUSY   Virtual machine has already run
+	 =======  ===========================================================
+	 -EBUSY   Virtual machine has already run, or SPE already initialized
 	 -EFAULT  Error accessing the SPE identifier
 	 -EINVAL  A different SPE instance already assigned, or no physical
                   CPUs found
 	 -ENXIO   SPE not supported or not properly configured, or the SPE
                   module not loaded
 	 -ENODEV  KVM_ARM_VCPU_HAS_SPE VCPU feature not set
-	 =======  =========================================================
+	 =======  ===========================================================
 
 Required.
 

@@ -361,3 +362,24 @@ responsible for making sure that the VCPU is run only on physical CPUs which
 share the specified SPE instance. If the VCPU has a PMU assigned, and there are
 no physical CPUs which share the same SPE and PMU instance, an error is
 returned.
+
+5.3 ATTRIBUTE: KVM_ARM_VCPU_SPE_INIT
+-----------------------------------
+
+:Parameters: no additional parameter in kvm_device_attr.addr
+
+Returns:
+
+	 =======  ============================================
+	 -EBUSY   SPE already initialized for this VCPU
+	 -ENXIO   SPE not supported or not properly configured
+	 =======  ============================================
+
+Required.
+
+Request initialization of the Statistical Profiling Extension for this VCPU.
+Must be done last, after SPE has been fully configured for the VCPU, and after
+the in-kernel irqchip has been initialized.
+
+KVM will refuse to run the VCPU and KVM_RUN will return an error if the SPE
+feature has been set for the VCPU, but SPE hasn't been initialized.

@@ -18,6 +18,7 @@ struct kvm_spe {
 
 struct kvm_vcpu_spe {
 	int irq_num;		/* Buffer management interrupt number */
+	bool initialized;	/* SPE initialized for the VCPU */
 };
 
 bool kvm_supports_spe(void);

@@ -25,6 +26,7 @@ bool kvm_supports_spe(void);
 #define vcpu_has_spe(vcpu)					\
 	(vcpu_has_feature(vcpu, KVM_ARM_VCPU_SPE))
 
+int kvm_spe_vcpu_first_run_init(struct kvm_vcpu *vcpu);
 void kvm_spe_destroy_vm(struct kvm *kvm);
 
 int kvm_spe_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr);

@@ -46,6 +48,10 @@ static __always_inline bool kvm_supports_spe(void)
 
 #define vcpu_has_spe(vcpu)	false
 
+static inline int kvm_spe_vcpu_first_run_init(struct kvm_vcpu *vcpu)
+{
+	return 0;
+}
 static inline void kvm_spe_destroy_vm(struct kvm *kvm)
 {
 }

@@ -449,6 +449,7 @@ enum {
 #define KVM_ARM_VCPU_SPE_CTRL		3
 #define   KVM_ARM_VCPU_SPE_IRQ		0
 #define   KVM_ARM_VCPU_SPE_ID		1
+#define   KVM_ARM_VCPU_SPE_INIT		2
 
 /* KVM_IRQ_LINE irq field index values */
 #define KVM_ARM_IRQ_VCPU2_SHIFT		28

@@ -1026,6 +1026,12 @@ int kvm_arch_vcpu_run_pid_change(struct kvm_vcpu *vcpu)
 			return ret;
 	}
 
+	if (vcpu_has_spe(vcpu)) {
+		ret = kvm_spe_vcpu_first_run_init(vcpu);
+		if (ret)
+			return ret;
+	}
+
 	ret = vgic_v5_finalize_ppi_state(kvm);
 	if (ret)
 		return ret;

@@ -59,6 +59,16 @@ bool kvm_supports_spe(void)
 	return !list_empty(&spe_pmus);
 }
 
+int kvm_spe_vcpu_first_run_init(struct kvm_vcpu *vcpu)
+{
+	struct kvm_vcpu_spe *vcpu_spe = &vcpu->arch.vcpu_spe;
+
+	if (!vcpu_spe->initialized)
+		return -EINVAL;
+
+	return 0;
+}
+
 void kvm_spe_destroy_vm(struct kvm *kvm)
 {
 	struct arm_spe_pmu *spe_pmu;

@@ -147,12 +157,16 @@ int kvm_spe_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
 {
 	struct kvm_vcpu_spe *vcpu_spe = &vcpu->arch.vcpu_spe;
 	struct kvm *kvm = vcpu->kvm;
+	struct kvm_spe *kvm_spe = &kvm->arch.kvm_spe;
 
 	lockdep_assert_held(&kvm->arch.config_lock);
 
 	if (!vcpu_has_spe(vcpu))
 		return -ENODEV;
 
+	if (vcpu_spe->initialized)
+		return -EBUSY;
+
 	switch (attr->attr) {
 	case KVM_ARM_VCPU_SPE_IRQ: {
 		int __user *uaddr = (int __user *)(long)attr->addr;

@@ -182,6 +196,21 @@ int kvm_spe_set_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
 
 		return kvm_spe_set_spe_id(vcpu, spe_id);
 	}
+	case KVM_ARM_VCPU_SPE_INIT:
+		if (!vcpu_spe->irq_num)
+			return -ENXIO;
+
+		if (!kvm_spe->spe_pmu)
+			return -ENXIO;
+
+		if (!vgic_initialized(kvm))
+			return -ENXIO;
+
+		if (kvm_vgic_set_owner(vcpu, vcpu_spe->irq_num, vcpu_spe))
+			return -ENXIO;
+
+		vcpu_spe->initialized = true;
+		return 0;
 	}
 
 	return -ENXIO;

@@ -240,6 +269,7 @@ int kvm_spe_has_attr(struct kvm_vcpu *vcpu, struct kvm_device_attr *attr)
 	switch(attr->attr) {
 	case KVM_ARM_VCPU_SPE_IRQ:
 	case KVM_ARM_VCPU_SPE_ID:
+	case KVM_ARM_VCPU_SPE_INIT:
 		return 0;
 	}