diff --git a/drivers/virtio/virtio_blk.c b/drivers/virtio/virtio_blk.c
index 992118c..1799f5c 100644
--- a/drivers/virtio/virtio_blk.c
+++ b/drivers/virtio/virtio_blk.c
@@ -115,6 +115,7 @@
 		return ret;
 
 	desc->blksz = 512;
+	desc->log2blksz = 9;
 	virtio_cread(dev, struct virtio_blk_config, capacity, &cap);
 	desc->lba = cap;