On Thu, Aug 30, 2018 at 12:53:39PM -0600, Logan Gunthorpe wrote: [...] > > When the PCI P2PDMA config option is selected the ACS bits in every > bridge port in the system are turned off to allow traffic to > pass freely behind the root port. At this time, the bit must be disabled > at boot so the IOMMU subsystem can correctly create the groups, though > this could be addressed in the future. There is no way to dynamically > disable the bit and alter the groups. Can you provide an example on how to test this ? Like kernel command line option, the doc patch does not have any such example. It would be nice to add. Maybe i have miss it in some of the patch. I just skimmed over for now. Cheers, Jérôme
