diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index ffc35a2a50..7196e75cbd 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -1047,7 +1047,20 @@
(such as CPUID level) that don't work. Until these issues are fixed,
it's a good idea to avoid using host-model
and use
custom
mode with just the CPU model from host
- capabilities XML.
+ capabilities XML.
+ (Since 1.2.11). PowerISA allows
+ processors to run VMs in binary compatibility mode supporting an
+ older version of ISA. Libvirt on PowerPC architecture uses the
+ host-model
to signify a guest mode CPU running in
+ binary compatibility mode. Example:
+ When a user needs a power7 VM to run in compatibility mode
+ on a Power8 host, this can be described in XML as follows :
+
+ <cpu mode='host-model'> + <model>power7</model> + </cpu> + ...+
host-passthrough