Mailing List Archive

PCI passthrough to PV guests no longer possible without IOMMU support on Xen 4.13

I've recently updated from Xen 4.12 to 4.13 and it seems that PCI
passthrough without IOMMU is no longer supported.

I have an old Proliant DL380 G3 that has no IOMMU support (xl dmesg:
(XEN) I/O virtualisation disabled), on which I used to pass a PCI
network card to one of my DomUs, but since updating to 4.13 I get the
following error message: "libxl: error:
libxl_create.c:979:libxl__domain_config_setdefault: passthrough not
supported on this platform"
As I see, the source of this issue is in libxl_create.c [0] where a
check has been introduced which will fail if passthrough is enabled
(either explicitly or by specifying at least one pci device to pass
through) and IOMMU is disabled.

Not sure if it was an intentional change or an oversight, but I would be
grateful for any workaround.




p.s.: I wasn't sure whether to post it here, or xen-devel, I hope this
list is the right one for this question.