docs: formatdomain: Mention that vhostuser interface with mode='server' waits for...

When starting a VM with a vhost-user interface in server mode qemu will
wait for the incoming connection without running CPUs. This isn't really
documented in our XML. Additionally when hotplugging the same interface
the above will not happen.

Signed-off-by: Peter Krempa <pkrempa@redhat.com>
Reviewed-by: Ján Tomko <jtomko@redhat.com>

diff --git a/docs/formatdomain.rst b/docs/formatdomain.rst
index 4a5241e6102d4f2e6958e6c5e224fb069970bcc7..fdb3c2459e41bdedcdeace856a873162f1364f40 100644 (file)
--- a/docs/formatdomain.rst
+++ b/docs/formatdomain.rst
@@ -6346,6 +6346,11 @@ two attributes ``enabled`` (which accepts ``yes`` and ``no``) and
 ``timeout`` which specifies the amount of seconds after which
 hypervisor tries to reconnect.
 
+Note that when ``mode='server'`` is used, the hypervisor will wait for the
+incoming connection to be established prior to actually running the VM. This is
+not possible when hotplugging an interface with such config so the VM will
+continue to run even when no connection is made. It's advised to use
+``mode='client'`` instead.
 
 vhost-user connection with passt backend
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^