if (!npages) {
                r = -ENOMEM;
-               slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
+               slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
+                               GFP_KERNEL);
                if (!slots)
                        goto out_free;
-               memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
                if (mem->slot >= slots->nmemslots)
                        slots->nmemslots = mem->slot + 1;
                slots->generation++;
        }
 
        r = -ENOMEM;
-       slots = kzalloc(sizeof(struct kvm_memslots), GFP_KERNEL);
+       slots = kmemdup(kvm->memslots, sizeof(struct kvm_memslots),
+                       GFP_KERNEL);
        if (!slots)
                goto out_free;
-       memcpy(slots, kvm->memslots, sizeof(struct kvm_memslots));
        if (mem->slot >= slots->nmemslots)
                slots->nmemslots = mem->slot + 1;
        slots->generation++;
        if (bus->dev_count > NR_IOBUS_DEVS-1)
                return -ENOSPC;
 
-       new_bus = kzalloc(sizeof(struct kvm_io_bus), GFP_KERNEL);
+       new_bus = kmemdup(bus, sizeof(struct kvm_io_bus), GFP_KERNEL);
        if (!new_bus)
                return -ENOMEM;
-       memcpy(new_bus, bus, sizeof(struct kvm_io_bus));
        kvm_io_bus_insert_dev(new_bus, dev, addr, len);
        rcu_assign_pointer(kvm->buses[bus_idx], new_bus);
        synchronize_srcu_expedited(&kvm->srcu);