2016-01-08 1:25 GMT+01:00 Alex Williamson <alex.l.william...@gmail.com>: > That's an interesting combination. This system is old enough that you have > something more like a traditional North Bridge, South Bridge setup. Intel > moved the memory controller to the processor in Nehalem & Westmere, but your > high speed Root Ports are on the IOH, part of chipset, not the processor. > These are root ports 00:01.0, 00:02.0, 00:03.0, and 00:07.0. These root > ports do have ACS support, so things below them are isolated from one > another. Rather than a PCH, you have an IOH. Those root ports are 00:1c.0, > 00:1c.2, and 00:1c.4. Those do not support ACS, do not have quirks, and are > part of a multifunction device, so they and everything behind them is > grouped together, that's your IOMMU group 9. > > Now, back to your IOH paths, devices 15:00.* are grouped together because > they lack ACS between the functions (I believe that Marvell SATA controller > is one of the ones that uses the wrong requester ID for DMA too). 14:00.0 > is in it's own group. Then come the PCIe switches. The downstream ports on > the switches do not support ACS, so everything downstream of them will be > grouped together. This is why group 13 contains not only the GTX 770, but > also the downstream port at 10:00.0. That's fine for a GPU assignment use > case, but would not work well for things like multi-port NICs or SR-IOV > devices where you want to assign each function to a different VM. The only > other interesting one is 08:00.0, where you've got a second layer of PCIe > switches. Everything in that hierarchy is already grouped together due to > the lack of ACS at 06:01.0, making group 21 pretty large. (I think that > other Marvell SATA controller also has DMA issues, but it should already > have quirks in the kernel) > > So it looks ok to me. The isolation isn't perfect, but it's ok for GPU > assignment.
Very thanks. now is the turn for the cpupin assignment. but is other history(and this isn't the thread) and I need learn more about it. Greetigs _______________________________________________ vfio-users mailing list vfio-users@redhat.com https://www.redhat.com/mailman/listinfo/vfio-users
