diff --git a/hw/ide/macio.c b/hw/ide/macio.c
index 76256eb8a8..664328d174 100644
--- a/hw/ide/macio.c
+++ b/hw/ide/macio.c
@@ -275,6 +275,7 @@ static void pmac_ide_atapi_transfer_cb(void *opaque, int ret)
         /* Non-block ATAPI transfer - just copy to RAM */
         s->io_buffer_size = MIN(s->io_buffer_size, io->len);
         cpu_physical_memory_write(io->addr, s->io_buffer, s->io_buffer_size);
+        io->len = 0;
         ide_atapi_cmd_ok(s);
         m->dma_active = false;
         goto done;