[vfio-users] Strange behavior with recent update. ACS(?) & VFIO

[Alex Williamson]

On Tue, Aug 2, 2016 at 4:02 PM, Mark <kram321 at gmail.com> wrote:

> Thank you for your input Alex, here is a pastie with some of the info you
> were interested in:
> VM powered off: http://pastie.org/10927534
> 00:1b.0 is the onboard, 01:00.0 and 01:00.1 are the nvidia gpu/nvidia
> audio.
>

Group 1
/sys/kernel/iommu_groups/1/devices/0000:00:01.0
/sys/kernel/iommu_groups/1/devices/0000:01:00.0
/sys/kernel/iommu_groups/1/devices/0000:01:00.1

Group 7
/sys/kernel/iommu_groups/7/devices/0000:00:1b.0



> Notice in that pastie the driver in use is snd_hda_intel, yet in this
> lspci -vvv (with the VM booted up) it is changed to vfio-pci, and they are
> still in the same iommu group.
> VM powered on: http://pastie.org/10927535
>

There must be some confusion over what an iommu group is because those are
clearly in separate groups with and without the VM running.  The driver is
simply the driver in use for the device, it doesn't change the composition
of the group.  IOMMU groups are assigned at boot and barring removing and
re-adding the device, don't change.  Thanks,

Alex
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://listman.redhat.com/archives/vfio-users/attachments/20160802/0372aefe/attachment.htm>