On Thu, 2015-12-03 at 09:44 -0600, Jeff wrote: > I'm pretty certain that ACS on the CPU root ports are working from the > output of sudo lspci -vvv for the 3 CPU PCI bridges > > (Heavily snipped) > 00:01.0 PCI bridge: Intel Corporation Xeon E5 v3/Core i7 PCI Express Root > Port 1 > Capabilities: [110 v1] Access Control Services > ACSCap: SrcValid+ TransBlk+ ReqRedir+ CmpltRedir+ > UpstreamFwd+ EgressCtrl- DirectTrans- > ACSCtl: SrcValid+ TransBlk- ReqRedir+ CmpltRedir+ > UpstreamFwd+ EgressCtrl- DirectTrans- > > However I don't understand the dmesg | grep output: > pci 0000:00:1c.0: Intel PCH root port ACS workaround enabled > pci 0000:00:1c.6: Intel PCH root port ACS workaround enabled > pci 0000:00:1c.7: Intel PCH root port ACS workaround enabled > > I understand that is from the PCH, but don't understand the "workaround" > being used for these ports. > > The IOMMU listing outputs proper isolation per device, but I wanted to make > sure there is no issues for expansion slots coming from the PCH and details > of the workaround. > > My brief understanding is that is has to do with properly grouping the > devices or something of that nature.
The kernel log indicates that ACS-equivalent isolation has been enabled for those PCH root ports: http://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=d99321b63b1f2cd386cdf20aefe4d8d3d414cb5b For more on IOMMU groups, see: http://vfio.blogspot.com/2014/08/iommu-groups-inside-and-out.html _______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
