diff --git a/lib/label/label.c b/lib/label/label.c
index c92d2cf8d..ca8502d41 100644
--- a/lib/label/label.c
+++ b/lib/label/label.c
@@ -1341,7 +1341,11 @@ void dev_set_last_byte(struct device *dev, uint64_t offset)
 	unsigned int phys_block_size = 0;
 	unsigned int block_size = 0;
 
-	dev_get_block_size(dev, &phys_block_size, &block_size);
+	if (!dev_get_block_size(dev, &phys_block_size, &block_size)) {
+		stack;
+		/* FIXME  ASSERT or regular error testing is missing */
+		return;
+	}
 
 	bcache_set_last_byte(scan_bcache, dev->bcache_fd, offset, phys_block_size);
 }