Linux kernel (drivers/vfio/pci/xe): Resetting a passed-through Intel GPU virtual function that does not support

Impact

Resetting a passed-through Intel GPU virtual function that does not support migration makes the host dereference a NULL migration context and oops in the reset-done callback. The host kernel goes down on a GPU-passthrough node, so one tenant resetting its own card is an outage for every tenant sharing that box.

Who can reach it

The reproducer runs through the sysfs reset attribute, which needs host root, but the same pci_reset_function() path is what runs on VFIO_DEVICE_RESET and on device-fd release - both of which a tenant holding /dev/vfio/<group> drives directly. Conditional on the xe_vfio_pci variant driver being bound to an Intel Xe SR-IOV VF that lacks migration support. Not reachable on NVIDIA-only fleets.

What to do

Update to a stable kernel carrying commits 8fa4113f / 73e53ff1. Interim: on Intel GPU SR-IOV nodes, bind VFs to plain vfio-pci rather than xe_vfio_pci where live migration is not needed, and block tenant-initiated device reset in the VMM.

References