diff --git a/README.adoc b/README.adoc
index f730efc..6a8236b 100644
--- a/README.adoc
+++ b/README.adoc
@@ -158,6 +158,8 @@ the disk image gets overwritten by a fresh filesystem and you lose all changes.
 
 Remember that if you forcibly turn QEMU off without `sync` or `poweroff` from inside the VM, e.g. by closing the QEMU window, disk changes may not be saved.
 
+When booting from <<initrd>> however without a disk, persistency is lost.
+
 === Message control
 
 We use `printk` a lot, and it shows on the QEMU terminal by default. If that annoys you (e.g. you want to see stdout separately), do: