diff --git a/hw/ide/ahci.c b/hw/ide/ahci.c
index 7a415db..a36a2ef 100644
--- a/hw/ide/ahci.c
+++ b/hw/ide/ahci.c
@@ -1164,6 +1164,7 @@ static void ahci_dma_start(IDEState *s, BlockDriverCompletionFunc *dma_cb)
     bm->cur_addr = 0;
     bm->sector_num = ide_get_sector(s);
     bm->nsector = s->nsector;
+    bm->cmd = 0;
     bmdma_cmd_writeb(bm, 0, 1);
 }