diff --git a/docs/man/xl.pod.1 b/docs/man/xl.pod.1
index e2bd32df76..9887f1b0c9 100644
--- a/docs/man/xl.pod.1
+++ b/docs/man/xl.pod.1
@@ -1263,6 +1263,7 @@ exact same syntax as in B<cpupool-cpu-add> above.
 =item B<cpupool-migrate> I<domain> I<cpu-pool>
 
 Moves a domain specified by domain-id or domain-name into a cpu-pool.
+Domain-0 can't be moved to another cpu-pool.
 
 =item B<cpupool-numa-split>