[CentOS-virt] PCI Passthrough not working

Mon May 16 10:29:09 UTC 2016
George Dunlap <dunlapg at umich.edu>

On Thu, May 12, 2016 at 12:11 PM, Francis Greaves <francis at choughs.net> wrote:
> I am running Xen 4.6 on CentOS 7 in a Dell Poweredge T430
> I need PCI Passthrough to get USB working. I am following the Xenproject
> Wiki
> I have enabled the Virtulasation in the BIOS.
> I have xen_pciback as a module
> I have issued the command:
>
> xl pci-assignable-add 00:1a0.0 and it shows up fine when I issue this xl
> pci-assignable-list
>
> I have pci=['00:1a.0'] on the DomU config file
> I have added this iommu=soft and swiotlb=force both together and separately
> to the kernel command line
> in the DomU (running Debian 8), but I get the same error each time.
>
> libxl: error: libxl_pci.c:999:do_pci_add: xc_assign_device failed: Operation
> not permitted
> libxl: error: libxl_create.c:1424:domcreate_attach_pci: libxl_device_pci_add
> failed: -3

Can you please attach the following:
1. The complete domU config file
2. A complete log of the command and all the output
3. The full output of "xl dmesg" just after you run the command

Thanks,
 -George