Add vfio-pci, igb_uio limitationsrocko

Change-Id: I7fc1d0c47bd4b949c5246c5fa1073676f5eebc67

1 files changed, 15 insertions, 1 deletions

diff --git a/doc/book-enea-nfv-access-release-info/doc/known_bugs_and_limitations.xml b/doc/book-enea-nfv-access-release-info/doc/known_bugs_and_limitations.xml
index ce9e9e0..66c54d7 100644
--- a/doc/book-enea-nfv-access-release-info/doc/known_bugs_and_limitations.xml
+++ b/doc/book-enea-nfv-access-release-info/doc/known_bugs_and_limitations.xml
@@ -92,6 +92,20 @@
       storage devices.</para>
     </listitem>
 
+    <listitem>
+      <para><remark>LXCR-9992</remark>Due to the way VFIO works, there are
+      certain limitations regarding which devices can be used with VFIO. Mainly, it
+      comes down to how IOMMU groups work. Any Virtual Function device can
+      be used with VFIO on its own, however, physical devices will require either
+      all ports to be bound to VFIO, or only some of them bound while others not
+      bound to anything at all.</para>
+
+      <para>If UEFI secure boot is enabled, the Linux kernel may disallow the
+      use of UIO on the system. Therefore, devices intended for use by the DPDK should be
+        bound to the <literal>vfio-pci</literal> kernel module rather than the 
+        <literal>igb_uio</literal>.</para>
+    </listitem>
+
     <listitem condition="hidden">
       <para><emphasis role="bold">PDF navigation</emphasis>: When using links
       to open other PDFs, or jump to another place in the same PDF, jumping
@@ -106,4 +120,4 @@
 
   <!-- <xi:include href="jiraissues_generated.xml"
               xmlns:xi="http://www.w3.org/2001/XInclude" /> -->
-</chapter>
\ No newline at end of file
+</chapter>