From 73bc4f185e314e9738125993b5a72585ea3c42c4 Mon Sep 17 00:00:00 2001
From: Andrea Bolognani <abologna@redhat.com>
Date: Wed, 6 Mar 2019 12:10:05 +0100
Subject: [PATCH] docs: Document configuration quirks for virtio devices
Some devices (namely virtio-scsi, virtio-gpu, virtio-keyboard,
virtio-tablet and virtio-mouse, plus virtio-crypto which is
not supported by libvirt) don't follow the same rules as all
other virtio devices, which is something that ought to be
documented.
Signed-off-by: Andrea Bolognani <abologna@redhat.com>
Reviewed-by: Cole Robinson <crobinso@redhat.com>
---
docs/formatdomain.html.in | 18 ++++++++++++++++++
1 file changed, 18 insertions(+)
diff --git a/docs/formatdomain.html.in b/docs/formatdomain.html.in
index eb00c01d96..949e2fc1b4 100644
--- a/docs/formatdomain.html.in
+++ b/docs/formatdomain.html.in
@@ -4132,6 +4132,24 @@
</dd>
</dl>
+ <p>
+ While the information outlined above applies to most virtio devices,
+ there are a few exceptions:
+ </p>
+
+ <ul>
+ <li>
+ for SCSI controllers, <code>virtio-scsi</code> must be used instead
+ of <code>virtio</code> for backwards compatibility reasons;
+ </li>
+ <li>
+ some devices, such as GPUs and input devices (keyboard, tablet and
+ mouse), are only defined in the virtio 1.0 spec and as such don't
+ have a transitional variant: the only accepted model is
+ <code>virtio</code>, which will result in a non-transitional device.
+ </li>
+ </ul>
+
<p>
For more details see the
<a href="https://lists.gnu.org/archive/html/qemu-devel/2018-12/msg00923.html">qemu patch posting</a> and the