diff --git a/arch/s390/kvm/kvm-s390.c b/arch/s390/kvm/kvm-s390.c
index 3beefadda0db..959a568a97be 100644
--- a/arch/s390/kvm/kvm-s390.c
+++ b/arch/s390/kvm/kvm-s390.c
@@ -5012,18 +5012,20 @@ int kvm_arch_prepare_memory_region(struct kvm *kvm,
 				   struct kvm_memory_slot *new,
 				   enum kvm_mr_change change)
 {
+	gpa_t size = new->npages * PAGE_SIZE;
+
 	/* A few sanity checks. We can have memory slots which have to be
 	   located/ended at a segment boundary (1MB). The memory in userland is
 	   ok to be fragmented into various different vmas. It is okay to mmap()
 	   and munmap() stuff in this slot after doing this call at any time */
 
-	if (mem->userspace_addr & 0xffffful)
+	if (new->userspace_addr & 0xffffful)
 		return -EINVAL;
 
-	if (mem->memory_size & 0xffffful)
+	if (size & 0xffffful)
 		return -EINVAL;
 
-	if (mem->guest_phys_addr + mem->memory_size > kvm->arch.mem_limit)
+	if ((new->base_gfn * PAGE_SIZE) + size > kvm->arch.mem_limit)
 		return -EINVAL;
 
 	/* When we are protected, we should not change the memory slots */
@@ -5052,8 +5054,9 @@ void kvm_arch_commit_memory_region(struct kvm *kvm,
 			break;
 		fallthrough;
 	case KVM_MR_CREATE:
-		rc = gmap_map_segment(kvm->arch.gmap, mem->userspace_addr,
-				      mem->guest_phys_addr, mem->memory_size);
+		rc = gmap_map_segment(kvm->arch.gmap, new->userspace_addr,
+				      new->base_gfn * PAGE_SIZE,
+				      new->npages * PAGE_SIZE);
 		break;
 	case KVM_MR_FLAGS_ONLY:
 		break;