diff --git a/hw/virtio-blk.c b/hw/virtio-blk.c
index bd6bbe6b14..a1df26dbcf 100644
--- a/hw/virtio-blk.c
+++ b/hw/virtio-blk.c
@@ -540,6 +540,7 @@ VirtIODevice *virtio_blk_init(DeviceState *dev, BlockConf *conf)
     register_savevm(dev, "virtio-blk", virtio_blk_id++, 2,
                     virtio_blk_save, virtio_blk_load, s);
     bdrv_set_removable(s->bs, 0);
+    s->bs->buffer_alignment = conf->logical_block_size;
 
     return &s->vdev;
 }