--- qemu/hw/ide/atapi.c	2018/04/24 19:30:25	1.1.1.2
+++ qemu/hw/ide/atapi.c	2018/04/24 19:51:00	1.1.1.3
@@ -352,14 +352,8 @@ static void ide_atapi_cmd_read_dma_cb(vo
     s->bus->dma->aiocb = bdrv_aio_readv(s->bs, (int64_t)s->lba << 2,
                                        &s->bus->dma->qiov, n * 4,
                                        ide_atapi_cmd_read_dma_cb, s);
-    if (!s->bus->dma->aiocb) {
-        /* Note: media not present is the most likely case */
-        ide_atapi_cmd_error(s, NOT_READY,
-                            ASC_MEDIUM_NOT_PRESENT);
-        goto eot;
-    }
-
     return;
+
 eot:
     bdrv_acct_done(s->bs, &s->acct);
     s->bus->dma->ops->add_status(s->bus->dma, BM_STATUS_INT);
@@ -889,8 +883,11 @@ static void cmd_start_stop_unit(IDEState
             ide_atapi_cmd_error(s, sense, ASC_MEDIA_REMOVAL_PREVENTED);
             return;
         }
-        bdrv_eject(s->bs, !start);
-        s->tray_open = !start;
+
+        if (s->tray_open != !start) {
+            bdrv_eject(s->bs, !start);
+            s->tray_open = !start;
+        }
     }
 
     ide_atapi_cmd_ok(s);