Refactor SRIOV VFIO test to use dynamic driver verification

- Store original driver for each VF PCI device before test starts
- Remove hardcoded 'mlx5_core' driver reference
- Verify original driver is restored after device detach
- Use get_pci_driver() function for dynamic driver detection
- Improve test robustness by working with any original driver

Signed-off-by: hholoubk <[email protected]>

AI assisted code and commit. Human reviewed.

Author: hholoubk

libvirt/tests/src/sriov/plug_unplug/sriov_attach_detach_device_vfio_variant_driver.py

@@ -51,6 +51,7 @@ def parse_iface_dict(pf_pci):
     vm = env.get_vm(vm_name)
     new_xml = vm_xml.VMXML.new_from_inactive_dumpxml(vm.name)
     orig_vm_xml = new_xml.copy()
+    original_drivers = {}
     try:
         libvirt_vmxml.remove_vm_devices_by_type(vm, 'interface')
         libvirt_vmxml.remove_vm_devices_by_type(vm, 'hostdev')
@@ -66,6 +67,10 @@ def parse_iface_dict(pf_pci):
         for idx in range(iface_number):
             test.log.info("TEST_STEP: Attach a hostdev interface/device to VM")
             vf_pci = utils_sriov.get_vf_pci_id(pf_pci, idx)
+            if vf_pci not in original_drivers:
+                original_driver = libvirt_vfio.get_pci_driver(vf_pci)
+                original_drivers[vf_pci] = original_driver
+                test.log.debug(f"Stored original driver for {vf_pci}: {original_driver}")
             iface_dict = parse_iface_dict(vf_pci)
             iface_dev = libvirt_vmxml.create_vm_device_by_type(device_type, iface_dict)
             virsh.attach_device(vm.name, iface_dev.xml, ignore_status=False,
@@ -99,7 +104,13 @@ def parse_iface_dict(pf_pci):
                       "device!" % vm_hostdevs)
         else:
             test.log.debug("Verify: The hostdev interface/device in VM xml is removed successfully - PASS")
-        libvirt_vfio.check_vfio_pci(vf_pci, exp_driver="mlx5_core")
+
+        # Verify original drivers are restored after detach
+        for idx in range(iface_number):
+            vf_pci = utils_sriov.get_vf_pci_id(pf_pci, idx)
+            original_driver = original_drivers[vf_pci]
+            libvirt_vfio.check_vfio_pci(vf_pci, exp_driver=original_driver)
+            test.log.debug(f"Verify: Original driver {original_driver} restored for {vf_pci} - PASS")
         test.log.debug("Verify: Check VF driver successfully after detaching hostdev interface/device - PASS")
         virsh.reboot(vm.name, ignore_status=False, debug=True)
         test.log.debug("Verify: VM reboot is successful after detaching hostdev interface/device - PASS")