On Tue, Sep 04, 2018 at 04:59:07PM +0800, tone.zhang wrote: > When binding the devices used by DPDK to the "uio-pci" 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 configuration 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..8f9ec8f 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 for used DPDK bound to the ``uio-pci`` kernel module, > please make > + sure that the IOMMU is disabled. We can add ``intel_iommu=off`` or > ``amd_iommu=off`` > + in ``GRUB_CMDLINE_LINUX`` in grub on x86_64 systems, or add > ``iommu.passthrough=1`` > + on arm64 system. > +
I think passthrough mode should work on x86 too. I remember running with iommu=pt setting in the kernel in the past. /Bruce
