[vfio-users] Linux iommu issue with peer-to-peer dma transfers between NVidia GTX 1080s

I forgot to add this Thread, it has far more info regarding the nVidia cards P2P issue when ACS is enabled: https://devtalk.nvidia.com/default/topic/883054/cuda-programming-and-performance/multi-gpu-peer-to-peer-access-failing-on-tesla-k80-/1

Re: [vfio-users] TSC unsable + radeon = creepy bugs

Hi Quentin, On 09/18/2017 09:01 PM, Quentin Deldycke wrote: > Using i7 4790k + r9 290, i have problems with my virtual machine when > restarted after suspend. > > I found that i happen to have a warning about incorrect TSC after > suspend the kernel give a config to disable TSC at boot time. When

Re: [vfio-users] Linux iommu issue with peer-to-peer dma transfers between NVidia GTX 1080s

Thanks for input on this - I am surprised to hear that Quadros and K4000 exhibit the same issues on bare metal! This means I need to revise my expectations. I will look at your suggestion involving virtual cliques and see where it takes me.. On Sat, 2017-09-23 at 11:26 -0600, Alex Williamson wr

Re: [vfio-users] Linux iommu issue with peer-to-peer dma transfers between NVidia GTX 1080s

I recall that there were some issues (Not necessarily yours) with P2P in nVidia cards related to ACS. While anyone that cares about IOMMU Groups will love ACS due to the better granularity, it broke what you want to use, and you may want to check if you can disable it. Check these: https://www