2 files changed, 42 insertions, 17 deletions

diff --git a/virt/kvm/arm/vgic/vgic-v3.c b/virt/kvm/arm/vgic/vgic-v3.c
index 2a11fe89943a..ce4476a08f5b 100644
--- a/virt/kvm/arm/vgic/vgic-v3.c
+++ b/virt/kvm/arm/vgic/vgic-v3.c
@@ -419,6 +419,29 @@ int vgic_v3_save_pending_tables(struct kvm *kvm)
 	return 0;
 }
 
+/**
+ * vgic_v3_rdist_overlap - check if a region overlaps with any
+ * existing redistributor region
+ *
+ * @kvm: kvm handle
+ * @base: base of the region
+ * @size: size of region
+ *
+ * Return: true if there is an overlap
+ */
+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size)
+{
+	struct vgic_dist *d = &kvm->arch.vgic;
+	struct vgic_redist_region *rdreg;
+
+	list_for_each_entry(rdreg, &d->rd_regions, list) {
+		if ((base + size > rdreg->base) &&
+			(base < rdreg->base + vgic_v3_rd_region_size(kvm, rdreg)))
+			return true;
+	}
+	return false;
+}
+
 /*
  * Check for overlapping regions and for regions crossing the end of memory
  * for base addresses which have already been set.
@@ -426,31 +449,23 @@ int vgic_v3_save_pending_tables(struct kvm *kvm)
 bool vgic_v3_check_base(struct kvm *kvm)
 {
 	struct vgic_dist *d = &kvm->arch.vgic;
-	gpa_t redist_size = KVM_VGIC_V3_REDIST_SIZE;
-	struct vgic_redist_region *rdreg =
-		list_first_entry(&d->rd_regions,
-				 struct vgic_redist_region, list);
-
-	redist_size *= atomic_read(&kvm->online_vcpus);
+	struct vgic_redist_region *rdreg;
 
 	if (!IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) &&
 	    d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE < d->vgic_dist_base)
 		return false;
 
-	if (rdreg && (rdreg->base + redist_size < rdreg->base))
-		return false;
-
-	/* Both base addresses must be set to check if they overlap */
-	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base) || !rdreg)
-		return true;
-
-	if (d->vgic_dist_base + KVM_VGIC_V3_DIST_SIZE <= rdreg->base)
-		return true;
+	list_for_each_entry(rdreg, &d->rd_regions, list) {
+		if (rdreg->base + vgic_v3_rd_region_size(kvm, rdreg) <
+			rdreg->base)
+			return false;
+	}
 
-	if (rdreg->base + redist_size <= d->vgic_dist_base)
+	if (IS_VGIC_ADDR_UNDEF(d->vgic_dist_base))
 		return true;
 
-	return false;
+	return !vgic_v3_rdist_overlap(kvm, d->vgic_dist_base,
+				      KVM_VGIC_V3_DIST_SIZE);
 }
 
 /**
diff --git a/virt/kvm/arm/vgic/vgic.h b/virt/kvm/arm/vgic/vgic.h
index fddd57ff6529..e9f192660097 100644
--- a/virt/kvm/arm/vgic/vgic.h
+++ b/virt/kvm/arm/vgic/vgic.h
@@ -276,6 +276,16 @@ vgic_v3_redist_region_full(struct vgic_redist_region *region)
 
 struct vgic_redist_region *vgic_v3_rdist_free_slot(struct list_head *rdregs);
 
+static inline size_t
+vgic_v3_rd_region_size(struct kvm *kvm, struct vgic_redist_region *rdreg)
+{
+	if (!rdreg->count)
+		return atomic_read(&kvm->online_vcpus) * KVM_VGIC_V3_REDIST_SIZE;
+	else
+		return rdreg->count * KVM_VGIC_V3_REDIST_SIZE;
+}
+bool vgic_v3_rdist_overlap(struct kvm *kvm, gpa_t base, size_t size);
+
 int vgic_its_resolve_lpi(struct kvm *kvm, struct vgic_its *its,
 			 u32 devid, u32 eventid, struct vgic_irq **irq);
 struct vgic_its *vgic_msi_to_its(struct kvm *kvm, struct kvm_msi *msi);