Index: uspace/srv/bd/hr/raid0.c
===================================================================
--- uspace/srv/bd/hr/raid0.c	(revision 263a2389bec7ca7beeb3ae5120941863de218291)
+++ uspace/srv/bd/hr/raid0.c	(revision 996d31acc0c6d09af6ff2425f7df18593ca1dc24)
@@ -256,4 +256,7 @@
 		return EINVAL;
 
+	if (vol->vflags & HR_VOL_FLAG_READ_ONLY && type == HR_BD_WRITE)
+		return ENOTSUP;
+
 	fibril_rwlock_read_lock(&vol->states_lock);
 	if (vol->state != HR_VOL_OPTIMAL) {