eal/linux: remove KNI restriction on IOVA

[dpdk.git] / doc / guides / prog_guide / env_abstraction_layer.rst

diff --git a/doc/guides/prog_guide/env_abstraction_layer.rst b/doc/guides/prog_guide/env_abstraction_layer.rst
index 6e59fae..6e7c208 100644 (file)
--- a/doc/guides/prog_guide/env_abstraction_layer.rst
+++ b/doc/guides/prog_guide/env_abstraction_layer.rst
@@ -249,7 +249,7 @@ manual memory management.
 
 + Using heap API's for externally allocated memory
 
-Using using a set of malloc heap API's is the recommended way to use externally
+Using a set of malloc heap API's is the recommended way to use externally
 allocated memory in DPDK. In this way, support for externally allocated memory
 is implemented through overloading the socket ID - externally allocated heaps
 will have socket ID's that would be considered invalid under normal
@@ -475,6 +475,9 @@ devices would fail anyway.
     ``RTE_PCI_DRV_NEED_IOVA_AS_VA`` flag is used to dictate that this PCI
     driver can only work in RTE_IOVA_VA mode.
 
+    When the KNI kernel module is detected, RTE_IOVA_PA mode is preferred as a
+    performance penalty is expected in RTE_IOVA_VA mode.
+
 IOVA Mode Configuration
 ~~~~~~~~~~~~~~~~~~~~~~~