Hello Bruce, Luca, Rami and Stephen,
Could you please help to review the change?
Any comments are welcome.
Thanks a lot!
Br,
Tone
-----Original Message-----
From: dev <dev-boun...@dpdk.org> On Behalf Of tone.zhang
Sent: Wednesday, September 5, 2018 1:18 PM
To: dev@dpdk.org
Cc: Gavin Hu (Arm Technology China) <gavin...@arm.com>;
bruce.richard...@intel.com; bl...@debian.org; roszenr...@gmail.com; nd
<n...@arm.com>
Subject: [dpdk-dev] [PATCH v3] doc: Clarify IOMMU usage with "uio_pci_generic"
kernel module
If the devices used for DPDK are bound to the "uio_pci_generic" kernel module,
the IOMMU should be disabled in order not to break the IO transmission because
of the virtual / physical address mapping.
The patch clarifies the IOMMU configurations on both x86_64 and arm64 systems.
Signed-off-by: tone.zhang <tone.zh...@arm.com>
---
doc/guides/linux_gsg/linux_drivers.rst | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/doc/guides/linux_gsg/linux_drivers.rst
b/doc/guides/linux_gsg/linux_drivers.rst
index 371a817..b46fc6a 100644
--- a/doc/guides/linux_gsg/linux_drivers.rst
+++ b/doc/guides/linux_gsg/linux_drivers.rst
@@ -48,6 +48,13 @@ be loaded as shown below:
``vfio-pci`` kernel module rather than ``igb_uio`` or ``uio_pci_generic``.
For more details see :ref:`linux_gsg_binding_kernel` below.
+.. note::
+
+ If the devices used for DPDK are bound to the ``uio_pci_generic`` kernel
module,
+ please make sure that the IOMMU is disabled. One can add
``intel_iommu=off`` or
+ ``intel_iommu=pt`` or ``amd_iommu=off`` in GRUB command line on x86_64
systems,
+ or add ``iommu.passthrough=1`` on arm64 system.
+
Since DPDK release 1.7 onward provides VFIO support, use of UIO is optional
for platforms that support using VFIO.
--
2.7.4
