Re: [PATCH] tests/sriov_basic: Validate PF unbind with VFs enabled

["Bernatowicz, Marcin" <marcin.bernatowicz@linux.intel.com>]

On 7/17/2026 3:44 PM, Lukasz Laguna wrote:
> Add new subtests covering PF driver unbind with VFs enabled in two
> scenarios:
> - with all VFs enabled,
> - with one VF enabled and probed.
>
> The tests verify that PF ends up unbound and VFs are disabled.
>
> Signed-off-by: Lukasz Laguna <lukasz.laguna@intel.com>
> ---
>   tests/sriov_basic.c | 82 +++++++++++++++++++++++++++++++++++++++++++++
>   1 file changed, 82 insertions(+)
>
> diff --git a/tests/sriov_basic.c b/tests/sriov_basic.c
> index 1e563cee9..1c5bb878e 100644
> --- a/tests/sriov_basic.c
> +++ b/tests/sriov_basic.c
> @@ -3,8 +3,13 @@
>    * Copyright(c) 2023 Intel Corporation. All rights reserved.
>    */
>   
> +#include <limits.h>
> +#include <dirent.h>
> +
>   #include "drmtest.h"
>   #include "igt_core.h"
> +#include "igt_device.h"
> +#include "igt_pci.h"
>   #include "igt_sriov_device.h"
>   
>   IGT_TEST_DESCRIPTION("Basic tests for enabling SR-IOV Virtual Functions");
> @@ -118,6 +123,51 @@ static void bind_unbind_vf(int pf_fd, unsigned int vf_num)
>   	igt_sriov_disable_vfs(pf_fd);
>   }
>   
> +static unsigned int count_pci_virtfn_entries(const char *pci_slot)
> +{
> +	char path[PATH_MAX];
> +	unsigned int count = 0;
> +	struct dirent *de;
> +	DIR *dir;
> +
> +	snprintf(path, sizeof(path), "/sys/bus/pci/devices/%s", pci_slot);
> +	dir = opendir(path);
> +	igt_assert_f(dir, "Failed to open %s\n", path);
> +
> +	while ((de = readdir(dir))) {
> +		if (!strncmp(de->d_name, "virtfn", strlen("virtfn")))
> +			count++;
> +	}
> +
> +	closedir(dir);
> +
> +	return count;
> +}
> +
> +/**
> + * SUBTEST: pf-unbind-with-vfs-enabled-numvfs-all
> + * Description:
> + *   Verify the PF driver unbind when all VFs are enabled.
> + *
> + * SUBTEST: pf-unbind-with-vf-probed
> + * Description:
> + *   Verify the PF driver unbind when one VF is enabled and probed.
> + */
> +static void pf_unbind_with_vfs_enabled(int pf_fd, unsigned int num_vfs, bool vf_probe)
> +{
> +	char pci_slot[NAME_MAX];
> +
> +	vf_probe ? igt_sriov_enable_driver_autoprobe(pf_fd) :
> +		   igt_sriov_disable_driver_autoprobe(pf_fd);
> +	igt_sriov_enable_vfs(pf_fd, num_vfs);
> +
> +	igt_device_get_pci_slot_name(pf_fd, pci_slot);
> +	igt_assert_eq(count_pci_virtfn_entries(pci_slot), num_vfs);
> +	igt_assert(!igt_pci_device_unbind(pci_slot));
Is hot-unbind with the PF fd kept open intentional ?
> +	igt_assert(!igt_pci_get_bound_driver_name(pci_slot, NULL, 0));
> +	igt_assert_eq(count_pci_virtfn_entries(pci_slot), 0);
> +}
> +
>   int igt_main()
>   {
>   	int pf_fd;
> @@ -210,7 +260,39 @@ int igt_main()
>   		}
>   	}
>   
> +	igt_subtest_group() {
> +		char pci_slot[NAME_MAX];
> +		char driver[NAME_MAX];
> +
> +		igt_fixture() {
> +			igt_device_get_pci_slot_name(pf_fd, pci_slot);
> +			igt_assert(igt_pci_get_bound_driver_name(pci_slot, driver, sizeof(driver)));
> +		}
> +
> +		igt_describe("Test unbinds the PF driver when all VFs are enabled");
> +		igt_subtest("pf-unbind-with-vfs-enabled-numvfs-all") {
> +			for_max_sriov_num_vfs(pf_fd, num_vfs) {
> +				pf_unbind_with_vfs_enabled(pf_fd, num_vfs, false);
> +			}
> +		}
> +
> +		igt_describe("Test unbinds the PF driver when one VF is enabled and probed");
> +		igt_subtest("pf-unbind-with-vf-probed") {
> +			pf_unbind_with_vfs_enabled(pf_fd, 1, true);
> +		}
> +
> +		igt_fixture() {
> +			if (!igt_pci_get_bound_driver_name(pci_slot, NULL, 0)) {
> +				close(pf_fd);
> +				pf_fd = -1;
> +				igt_assert(!igt_pci_driver_bind(driver, pci_slot));
> +				pf_fd = drm_open_driver(DRIVER_ANY);
We should ensure we reopen the same PF device, especially in multi-GPU 
configurations, by setting a device filter as in igt@core_hotunplug.
> +			}
> +		}
> +	}
> +
>   	igt_fixture() {
> +		igt_abort_on_f(pf_fd < 0, "Device is not accessible\n");
>   		igt_sriov_disable_vfs(pf_fd);
>   		/* abort to avoid execution of next tests with enabled VFs */
>   		igt_abort_on_f(igt_sriov_get_enabled_vfs(pf_fd) > 0, "Failed to disable VF(s)");