Re: [PATCH i-g-t 3/4] tests/intel/xe_sriov_vfio: Add open-basic subtest

Laguna, Lukasz
2026-03-24T14:18:05Z

On 3/18/2026 17:14, Marcin Bernatowicz wrote:
> The subtest binds a VF to xe-vfio-pci, opens its VFIO group, and
> verifies basic VFIO access with a minimal group status query. This
> provides a simple smoke test for VFIO device setup.
>
> Signed-off-by: Marcin Bernatowicz <marcin.bernatowicz@linux.intel.com>
> Cc: Adam Miszczak <adam.miszczak@linux.intel.com>
> Cc: Jakub Kolakowski <jakub1.kolakowski@intel.com>
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Cc: Lukasz Laguna <lukasz.laguna@intel.com>
> ---
> tests/intel/xe_sriov_vfio.c | 136 ++++++++++++++++++++++++++++++++++++
> 1 file changed, 136 insertions(+)
>
> diff --git a/tests/intel/xe_sriov_vfio.c b/tests/intel/xe_sriov_vfio.c
> index a2b2959e2..6a5cc536b 100644
> --- a/tests/intel/xe_sriov_vfio.c
> +++ b/tests/intel/xe_sriov_vfio.c
> @@ -6,6 +6,8 @@
> #include <ctype.h>
> #include <dirent.h>
> #include <fcntl.h>
> +#include <linux/vfio.h>
> +#include <sys/ioctl.h>
>
> #include "drmtest.h"
> #include "igt_core.h"
> @@ -29,6 +31,9 @@
> *
> * SUBTEST: bind-unbind-vfs
> * Description: Enable VFs and bind/unbind each one to xe-vfio-pci via driver_override.
> + *
> + * SUBTEST: open-basic
> + * Description: Bind VF to xe-vfio-pci and perform minimal VFIO group open and status ioctl.
> */
>
> IGT_TEST_DESCRIPTION("Xe SR-IOV VFIO tests (xe-vfio-pci)");
> @@ -199,6 +204,109 @@ static void restore_xe_vfio_module(void)
> restore_xe_vfio_on_exit = false;
> }
>
> +static bool vf_iommu_group_id_alloc(const char *pci_slot, char **out_group_id)
> +{
> + char path[PATH_MAX];
> + char link[PATH_MAX];
> + ssize_t len;
> + const char *base;
> +
> + igt_assert(out_group_id);
> + *out_group_id = NULL;
> +
> + snprintf(path, sizeof(path), "/sys/bus/pci/devices/%s/iommu_group", pci_slot);
> + len = readlink(path, link, sizeof(link) - 1);
> + if (len < 0)
> + return false;
> +
> + link[len] = '\0';
> + base = strrchr(link, '/');
> + if (!base || !base[1])
> + return false;
> +
> + *out_group_id = strdup(base + 1);
> + igt_assert(*out_group_id);
> +
> + return true;
> +}
> +
> +struct vfio_dev_fds {
> + int container_fd;
> + int group_fd;
> + int device_fd;
> + char *group_id;
> +};
> +
> +static void vfio_open_group(const char *pci_slot, struct vfio_dev_fds *out,
> + struct vfio_group_status *out_group_status)
> +{
> + char group_path[PATH_MAX];
> + int ret;
> +
> + igt_assert(out);
> + *out = (struct vfio_dev_fds){
> + .container_fd = -1,
> + .group_fd = -1,
> + .device_fd = -1,
> + .group_id = NULL,
> + };
> +
> + if (out_group_status)
> + *out_group_status = (struct vfio_group_status){
> + .argsz = sizeof(*out_group_status)
> + };
> +
> + if (!vf_iommu_group_id_alloc(pci_slot, &out->group_id))
> + igt_skip("No IOMMU group (IOMMU disabled or not exposed)\n");
> +
> + out->container_fd = open("/dev/vfio/vfio", O_RDWR | O_CLOEXEC);
> + if (out->container_fd < 0)
> + igt_skip("/dev/vfio/vfio not available\n");
> +
> + snprintf(group_path, sizeof(group_path), "/dev/vfio/%s", out->group_id);
> + out->group_fd = open(group_path, O_RDWR | O_CLOEXEC);
> + igt_require_f(out->group_fd >= 0, "Failed to open %s (%d)\n", group_path, -errno);
> +
> + if (out_group_status) {
> + ret = ioctl(out->group_fd, VFIO_GROUP_GET_STATUS, out_group_status);
> + igt_require_f(ret == 0, "VFIO_GROUP_GET_STATUS failed (%d)\n", -errno);
> + }
> +}
> +
> +static void vfio_close_device(struct vfio_dev_fds *fds)
> +{
> + if (!fds)
> + return;
> +
> + if (fds->device_fd >= 0)
> + close(fds->device_fd);
> +
> + if (fds->group_fd >= 0 && fds->container_fd >= 0)
> + ioctl(fds->group_fd, VFIO_GROUP_UNSET_CONTAINER, &fds->container_fd);
> +
> + if (fds->group_fd >= 0)
> + close(fds->group_fd);
> + if (fds->container_fd >= 0)
> + close(fds->container_fd);
> +
> + free(fds->group_id);
> +
> + fds->container_fd = -1;
> + fds->group_fd = -1;
> + fds->device_fd = -1;
> + fds->group_id = NULL;
> +}
> +
> +static void vfio_open_basic(const char *pci_slot)
> +{
> + struct vfio_dev_fds fds;
> + struct vfio_group_status group_status;
> +
> + vfio_open_group(pci_slot, &fds, &group_status);
> + igt_info("VFIO group %s status flags=0x%x\n", fds.group_id, group_status.flags);
> + vfio_close_device(&fds);
> +}
> +
> int igt_main()
> {
> igt_fixture() {
> @@ -250,6 +358,34 @@ int igt_main()
> }
> }
>
> + igt_describe("Bind VF to xe-vfio-pci and do minimal VFIO open and GET_STATUS.");
> + igt_subtest("open-basic") {
> + char *slot = NULL;
> +
> + igt_skip_on_f(igt_kmod_load(XE_VFIO_PCI_MOD, NULL),
> + "Failed to load %s\n", XE_VFIO_PCI_MOD);
> + restore_xe_vfio_on_exit = true;
> +
> + open_pf();
> +
> + igt_sriov_disable_driver_autoprobe(pf_fd);
> + igt_sriov_enable_vfs(pf_fd, 1);

Maybe vf_num = 1 and then use variable?

> +
> + igt_require_f(!igt_pci_system_reinit(), "Failed to refresh PCI state\n");
> + igt_sriov_enable_driver_autoprobe(pf_fd);
> +
> + slot = vf_pci_slot_alloc(1);
> +
> + vf_unbind_override(1);

The same as in previous patch - is this unbind needed?

> + vf_bind_override(1, XE_VFIO_PCI_DRV);
> +
> + vfio_open_basic(slot);
> +
> + vf_unbind_override(1);
> + free(slot);
> + igt_sriov_disable_vfs(pf_fd);
> + }
> +
> igt_fixture() {
> cleanup_pf();
> restore_xe_vfio_module();