5 files changed, 70 insertions, 10 deletions

diff --git a/virt/kvm/arm/vgic/vgic-init.c b/virt/kvm/arm/vgic/vgic-init.c
index 0ea64a1beff9..962bb577a1a0 100644
--- a/virt/kvm/arm/vgic/vgic-init.c
+++ b/virt/kvm/arm/vgic/vgic-init.c
@@ -226,6 +226,27 @@ static int kvm_vgic_dist_init(struct kvm *kvm, unsigned int nr_spis)
 	return 0;
 }
 
+/**
+ * kvm_vgic_vcpu_init() - Register VCPU-specific KVM iodevs
+ * @vcpu: pointer to the VCPU being created and initialized
+ */
+int kvm_vgic_vcpu_init(struct kvm_vcpu *vcpu)
+{
+	int ret = 0;
+	struct vgic_dist *dist = &vcpu->kvm->arch.vgic;
+
+	if (!irqchip_in_kernel(vcpu->kvm))
+		return 0;
+
+	/*
+	 * If we are creating a VCPU with a GICv3 we must also register the
+	 * KVM io device for the redistributor that belongs to this VCPU.
+	 */
+	if (dist->vgic_model == KVM_DEV_TYPE_ARM_VGIC_V3)
+		ret = vgic_register_redist_iodev(vcpu);
+	return ret;
+}
+
 static void kvm_vgic_vcpu_enable(struct kvm_vcpu *vcpu)
 {
 	if (kvm_vgic_global_state.type == VGIC_V2)
diff --git a/virt/kvm/arm/vgic/vgic-kvm-device.c b/virt/kvm/arm/vgic/vgic-kvm-device.c
index 69ccfd5b2271..10ae6f394b71 100644
--- a/virt/kvm/arm/vgic/vgic-kvm-device.c
+++ b/virt/kvm/arm/vgic/vgic-kvm-device.c
@@ -86,8 +86,13 @@ int kvm_vgic_addr(struct kvm *kvm, unsigned long type, u64 *addr, bool write)
 		break;
 	case KVM_VGIC_V3_ADDR_TYPE_REDIST:
 		r = vgic_check_type(kvm, KVM_DEV_TYPE_ARM_VGIC_V3);
+		if (r)
+			break;
+		if (write) {
+			r = vgic_v3_set_redist_base(kvm, *addr);
+			goto out;
+		}
 		addr_ptr = &vgic->vgic_redist_base;
-		alignment = SZ_64K;
 		break;
 	default:
 		r = -ENODEV;
diff --git a/virt/kvm/arm/vgic/vgic-mmio-v3.c b/virt/kvm/arm/vgic/vgic-mmio-v3.c
index 168269b4e28d..99da1a207c19 100644
--- a/virt/kvm/arm/vgic/vgic-mmio-v3.c
+++ b/virt/kvm/arm/vgic/vgic-mmio-v3.c
@@ -565,7 +565,7 @@ unsigned int vgic_v3_init_dist_iodev(struct vgic_io_device *dev)
  *
  * Return 0 on success, -ERRNO otherwise.
  */
-static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
+int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 {
 	struct kvm *kvm = vcpu->kvm;
 	struct vgic_dist *vgic = &kvm->arch.vgic;
@@ -574,6 +574,18 @@ static int vgic_register_redist_iodev(struct kvm_vcpu *vcpu)
 	gpa_t rd_base, sgi_base;
 	int ret;
 
+	/*
+	 * We may be creating VCPUs before having set the base address for the
+	 * redistributor region, in which case we will come back to this
+	 * function for all VCPUs when the base address is set.  Just return
+	 * without doing any work for now.
+	 */
+	if (IS_VGIC_ADDR_UNDEF(vgic->vgic_redist_base))
+		return 0;
+
+	if (!vgic_v3_check_base(kvm))
+		return -EINVAL;
+
 	rd_base = vgic->vgic_redist_base + kvm_vcpu_get_idx(vcpu) * SZ_64K * 2;
 	sgi_base = rd_base + SZ_64K;
 
@@ -619,7 +631,7 @@ static void vgic_unregister_redist_iodev(struct kvm_vcpu *vcpu)
 	kvm_io_bus_unregister_dev(vcpu->kvm, KVM_MMIO_BUS, &sgi_dev->dev);
 }
 
-int vgic_register_redist_iodevs(struct kvm *kvm)
+static int vgic_register_all_redist_iodevs(struct kvm *kvm)
 {
 	struct kvm_vcpu *vcpu;
 	int c, ret = 0;
@@ -641,6 +653,33 @@ int vgic_register_redist_iodevs(struct kvm *kvm)
 	return ret;
 }
 
+int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr)
+{
+	struct vgic_dist *vgic = &kvm->arch.vgic;
+	int ret;
+
+	/* vgic_check_ioaddr makes sure we don't do this twice */
+	ret = vgic_check_ioaddr(kvm, &vgic->vgic_redist_base, addr, SZ_64K);
+	if (ret)
+		return ret;
+
+	vgic->vgic_redist_base = addr;
+	if (!vgic_v3_check_base(kvm)) {
+		vgic->vgic_redist_base = VGIC_ADDR_UNDEF;
+		return -EINVAL;
+	}
+
+	/*
+	 * Register iodevs for each existing VCPU.  Adding more VCPUs
+	 * afterwards will register the iodevs when needed.
+	 */
+	ret = vgic_register_all_redist_iodevs(kvm);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
 int vgic_v3_has_attr_regs(struct kvm_device *dev, struct kvm_device_attr *attr)
 {
 	const struct vgic_register_region *region;
diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 2d53d7a24bda..bb35078f4e40 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -397,12 +397,6 @@ int vgic_v3_map_resources(struct kvm *kvm)
 		goto out;
 	}
 
-	ret = vgic_register_redist_iodevs(kvm);
-	if (ret) {
-		kvm_err("Unable to register VGICv3 redist MMIO regions\n");
-		goto out;
-	}
-
 	if (vgic_has_its(kvm)) {
 		ret = vgic_register_its_iodevs(kvm);
 		if (ret) {
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index 89eb935c05be..5f17eace077c 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -174,7 +174,8 @@ int vgic_v3_probe(const struct gic_kvm_info *info);
 int vgic_v3_map_resources(struct kvm *kvm);
 int vgic_v3_lpi_sync_pending_status(struct kvm *kvm, struct vgic_irq *irq);
 int vgic_v3_save_pending_tables(struct kvm *kvm);
-int vgic_register_redist_iodevs(struct kvm *kvm);
+int vgic_v3_set_redist_base(struct kvm *kvm, u64 addr);
+int vgic_register_redist_iodev(struct kvm_vcpu *vcpu);
 bool vgic_v3_check_base(struct kvm *kvm);
 
 void vgic_v3_load(struct kvm_vcpu *vcpu);