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@@ -404,7 +404,7 @@ struct virtq_desc {
\end{lstlisting}
The number of descriptors in the table is defined by the queue size
-for this virtqueue.
+for this virtqueue: this is the maximum possible descriptor chain length.
\begin{note}
The legacy \hyperref[intro:Virtio PCI Draft]{[Virtio PCI Draft]}
@@ -456,6 +456,9 @@ VIRTIO_F_INDIRECT_DESC feature was negotiated. The driver MUST NOT
set the VIRTQ_DESC_F_INDIRECT flag within an indirect descriptor (ie. only
one table per descriptor).
+A driver MUST NOT create a descriptor chain longer than the Queue Size of
+the device.
+
\devicenormative{\paragraph}{Indirect Descriptors}{Basic Facilities of a Virtio Device / Virtqueues / The Virtqueue Descriptor Table / Indirect Descriptors}
The device MUST ignore the write-only flag (\field{flags}\&VIRTQ_DESC_F_WRITE) in the descriptor that refers to an indirect table.