diff --git a/man/systemd-soft-reboot.service.xml b/man/systemd-soft-reboot.service.xml
index f2bbd81468..5960cf90a6 100644
--- a/man/systemd-soft-reboot.service.xml
+++ b/man/systemd-soft-reboot.service.xml
@@ -119,7 +119,9 @@
     processes running during a soft-reboot operation requires disconnecting the service comprehensively from
     the rest of the OS, i.e. minimizing IPC and reducing sharing of resources with the rest of the OS. A
     possible mechanism to achieve this is the concept of <ulink
-    url="https://systemd.io/PORTABLE_SERVICES">Portable Services</ulink>.</para>
+    url="https://systemd.io/PORTABLE_SERVICES">Portable Services</ulink>, but make sure no resource from
+    the host's root filesystem is pinned via <varname>BindPaths=</varname> or similar unit settings,
+    otherwise the old root filesystem will be kept in memory as long as the unit is running.</para>
 
     <para>If units shall be left running until the very end of shutdown during a soft reboot operation, but
     shall be terminated regularly during other forms of shutdown, it's recommended to set