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@@ -98,61 +98,15 @@ which was not offered. The device SHOULD accept any valid subset
of features the driver accepts, otherwise it MUST fail to set the
FEATURES_OK \field{device status} bit when the driver writes it.
-\subsection{Legacy Interface: A Note on transitions from earlier drafts}\label{sec:Basic Facilities of a Virtio Device / Feature Bits / Legacy Interface: A Note on transitions from earlier drafts}
-
-%TODO: split out conformance sections
-Earlier drafts of this specification (i.e. revisions before 1.0,
-see e.g. \hyperref[intro:Virtio PCI Draft]{[Virtio PCI Draft]})
-defined a similar, but different
-interface between the driver and the device.
-Since these are widely deployed, this specification
-accommodates OPTIONAL features to simplify transition
-from these earlier draft interfaces.
-
-Specifically devices and drivers MAY support:
-\begin{description}
-\item[Legacy Interface]
- is an interface specified by an earlier draft of this specification
- (before 1.0)
-\item[Legacy Device]
- is a device implemented before this specification was released,
- and implementing a legacy interface on the host side
-\item[Legacy Driver]
- is a driver implemented before this specification was released,
- and implementing a legacy interface on the guest side
-\end{description}
-
-Legacy devices and legacy drivers are not compliant with this
-specification.
-
-\begin{note}
- No legacy interfaces are required; ie. don't implement them unless you
- have a need for backwards compatibility!
-\end{note}
-
-To simplify transition from these earlier draft interfaces,
-a device MAY implement:
-
-\begin{description}
-\item[Transitional Device]
- a device supporting both drivers conforming to this
- specification, and allowing legacy drivers.
-\end{description}
-
-Similarly, a driver MAY implement:
-\begin{description}
-\item[Transitional Driver]
- a driver supporting both devices conforming to this
- specification, and legacy devices.
-\end{description}
-
-Devices or drivers with no legacy compatibility are referred to as
-non-transitional devices and drivers, respectively.
+\subsection{Legacy Interface: A Note on Feature
+Bits}\label{sec:Basic Facilities of a Virtio Device / Feature
+Bits / Legacy Interface: A Note on Feature Bits}
Transitional Drivers MUST detect Legacy Devices by detecting that
the feature bit VIRTIO_F_VERSION_1 is not offered.
Transitional devices MUST detect Legacy drivers by detecting that
VIRTIO_F_VERSION_1 has not been acknowledged by the driver.
+
In this case device is used through the legacy interface.
Legacy interface support is OPTIONAL.