1 files changed, 41 insertions, 2 deletions

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;