diff --git a/drivers/md/md.c b/drivers/md/md.c
index 0a447a1..41f8810 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -344,6 +344,10 @@
 		bio_io_error(bio);
 		return;
 	}
+	if (mddev->ro == 1 && unlikely(rw == WRITE)) {
+		bio_endio(bio, bio_sectors(bio) == 0 ? 0 : -EROFS);
+		return;
+	}
 	smp_rmb(); /* Ensure implications of  'active' are visible */
 	rcu_read_lock();
 	if (mddev->suspended) {