[PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Nitin Gote]

The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
but leave the GPU idle, so the kernel hotplug path is never exercised
against an active VM, exec queue and BOs.

Add six new dedicated *-with-load subtests that run a GPU spinner across
the unbind/unplug sequence so the device is removed while a workload is
actively using it.

The workload helpers use an explicit chipset dispatch block in
workload_start()/stop() so that other vendors can contribute
support by adding an else-if branch. New subtests are gated on
workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
and returns false (SKIP) on any other driver.

igt_spin_free() is avoided in workload_stop() since the device may be
gone by then — igt_spin_end() writes the stop condition via a userspace
mmap and lets the DRM fd close reclaim kernel-side resources.

Validated on BMG and DG2 with a KASAN-enabled kernel:
all six new subtests pass with no KASAN reports.

v2: Pass the hotunplug priv struct to workload_start()/stop()
    and dispatch via an explicit if/else-if chipset block to invite
    other vendors to contribute. (Janusz)

Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Assisted-by: Copilot:claude-opus-4.7
Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
---
 tests/core_hotunplug.c | 290 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 290 insertions(+)

diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
index 7c9dae1bf..38dcbb97d 100644
--- a/tests/core_hotunplug.c
+++ b/tests/core_hotunplug.c
@@ -80,6 +80,34 @@
  * SUBTEST: unplug-rescan
  * Description: Check if a device believed to be closed can be cleanly
  *		unplugged, then restored
+ *
+ * SUBTEST: hotunbind-rebind-with-load
+ * Description: Check if the driver can be cleanly unbound from an open device
+ *		with a background GPU workload in flight, then released and
+ *		rebound
+ *
+ * SUBTEST: hotunplug-rescan-with-load
+ * Description: Check if an open device with a background GPU workload in
+ *		flight can be cleanly unplugged, then released and restored
+ *
+ * SUBTEST: hotrebind-with-load
+ * Description: Check if the driver can be cleanly rebound to a device with a
+ *		still open hot unbound driver instance while a background GPU
+ *		workload is in flight
+ *
+ * SUBTEST: hotreplug-with-load
+ * Description: Check if a hot unplugged and still open device can be cleanly
+ *		restored while a background GPU workload is in flight
+ *
+ * SUBTEST: hotrebind-lateclose-with-load
+ * Description: Check if a hot unbound driver instance still open after hot
+ *		rebind with a background GPU workload in flight can be cleanly
+ *		released
+ *
+ * SUBTEST: hotreplug-lateclose-with-load
+ * Description: Check if an instance of a still open while hot replugged
+ *		device with a background GPU workload in flight can be cleanly
+ *		released
  */
 
 IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
@@ -565,6 +593,52 @@ static void set_filter_from_device(int fd)
 	igt_assert_eq(igt_device_filter_add(filter), 1);
 }
 
+/* GPU workload helpers */
+
+struct gpu_workload {
+	igt_spin_t *spin;
+	uint64_t ahnd;
+};
+
+static bool workload_available(int chipset)
+{
+	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
+}
+
+static void workload_start(struct hotunplug *priv, int fd,
+			   struct gpu_workload *w)
+{
+	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
+		local_debug("%s\n", "starting GPU spinner");
+		priv->failure = "GPU workload start failure!";
+		w->ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
+		w->spin = igt_spin_new(fd, .ahnd = w->ahnd);
+		priv->failure = NULL;
+	}
+}
+
+static void workload_stop(struct hotunplug *priv, struct gpu_workload *w)
+{
+	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
+		if (!w->spin)
+			return;
+
+		/*
+		 * The device may be gone (unbind/unplug), so avoid
+		 * igt_spin_free(): on Xe it would wait forever on a syncobj
+		 * that never signals; on i915 it would touch the dead fd via
+		 * gem_munmap()/gem_close(). Instead, end the spinner via a
+		 * userspace mmap write and let the DRM fd close reclaim the
+		 * kernel-side resources.
+		 */
+		local_debug("%s\n", "stopping GPU spinner");
+		igt_spin_end(w->spin);
+		put_ahnd(w->ahnd);
+		w->spin = NULL;
+		w->ahnd = 0;
+	}
+}
+
 /* Subtests */
 
 static void unbind_rebind(struct hotunplug *priv)
@@ -679,6 +753,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
 	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
 }
 
+static void hotunbind_rebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	driver_bind(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotunplug_rescan_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	bus_rescan(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(priv, &w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(priv, &w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
 /* Main */
 
 int igt_main()
@@ -817,6 +1035,78 @@ int igt_main()
 			recover(&priv);
 	}
 
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
+		igt_subtest("hotunbind-rebind-with-load")
+			hotunbind_rebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
+		igt_subtest("hotunplug-rescan-with-load")
+			hotunplug_rescan_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
+		igt_subtest("hotrebind-with-load")
+			hotrebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
+		igt_subtest("hotreplug-with-load")
+			hotreplug_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotrebind-lateclose-with-load")
+			hotrebind_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotreplug-lateclose-with-load")
+			hotreplug_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
 	igt_fixture() {
 		post_healthcheck(&priv);
 
-- 
2.50.1

Re: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Janusz Krzysztofik]

Hi Nitin,

On Mon, 2026-05-18 at 17:31 +0530, Nitin Gote wrote:
> The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
> but leave the GPU idle, so the kernel hotplug path is never exercised
> against an active VM, exec queue and BOs.
> 
> Add six new dedicated *-with-load subtests that run a GPU spinner across
> the unbind/unplug sequence so the device is removed while a workload is
> actively using it.
> 
> The workload helpers use an explicit chipset dispatch block in
> workload_start()/stop() so that other vendors can contribute
> support by adding an else-if branch. New subtests are gated on
> workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
> and returns false (SKIP) on any other driver.
> 
> igt_spin_free() is avoided in workload_stop() since the device may be
> gone by then — igt_spin_end() writes the stop condition via a userspace
> mmap and lets the DRM fd close reclaim kernel-side resources.
> 
> Validated on BMG and DG2 with a KASAN-enabled kernel:
> all six new subtests pass with no KASAN reports.
> 
> v2: Pass the hotunplug priv struct to workload_start()/stop()
>     and dispatch via an explicit if/else-if chipset block to invite
>     other vendors to contribute. (Janusz)
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Assisted-by: Copilot:claude-opus-4.7
> Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
> ---
>  tests/core_hotunplug.c | 290 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 290 insertions(+)
> 
> diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
> index 7c9dae1bf..38dcbb97d 100644
> --- a/tests/core_hotunplug.c
> +++ b/tests/core_hotunplug.c
> @@ -80,6 +80,34 @@
>   * SUBTEST: unplug-rescan
>   * Description: Check if a device believed to be closed can be cleanly
>   *		unplugged, then restored
> + *
> + * SUBTEST: hotunbind-rebind-with-load
> + * Description: Check if the driver can be cleanly unbound from an open device
> + *		with a background GPU workload in flight, then released and
> + *		rebound
> + *
> + * SUBTEST: hotunplug-rescan-with-load
> + * Description: Check if an open device with a background GPU workload in
> + *		flight can be cleanly unplugged, then released and restored
> + *
> + * SUBTEST: hotrebind-with-load
> + * Description: Check if the driver can be cleanly rebound to a device with a
> + *		still open hot unbound driver instance while a background GPU
> + *		workload is in flight
> + *
> + * SUBTEST: hotreplug-with-load
> + * Description: Check if a hot unplugged and still open device can be cleanly
> + *		restored while a background GPU workload is in flight
> + *
> + * SUBTEST: hotrebind-lateclose-with-load
> + * Description: Check if a hot unbound driver instance still open after hot
> + *		rebind with a background GPU workload in flight can be cleanly
> + *		released
> + *
> + * SUBTEST: hotreplug-lateclose-with-load
> + * Description: Check if an instance of a still open while hot replugged
> + *		device with a background GPU workload in flight can be cleanly
> + *		released
>   */
>  
>  IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
> @@ -565,6 +593,52 @@ static void set_filter_from_device(int fd)
>  	igt_assert_eq(igt_device_filter_add(filter), 1);
>  }
>  
> +/* GPU workload helpers */
> +
> +struct gpu_workload {
> +	igt_spin_t *spin;
> +	uint64_t ahnd;
> +};

Sorry for not touching this before when asking you to make room for other 
vendors in functions, but now as we have that in place, I think it would 
be good to have the same also for data.  A union maybe, with its members 
named after vendors?

Thanks,
Janusz


> +
> +static bool workload_available(int chipset)
> +{
> +	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
> +}
> +
> +static void workload_start(struct hotunplug *priv, int fd,
> +			   struct gpu_workload *w)
> +{
> +	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
> +		local_debug("%s\n", "starting GPU spinner");
> +		priv->failure = "GPU workload start failure!";
> +		w->ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
> +		w->spin = igt_spin_new(fd, .ahnd = w->ahnd);
> +		priv->failure = NULL;
> +	}
> +}
> +
> +static void workload_stop(struct hotunplug *priv, struct gpu_workload *w)
> +{
> +	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
> +		if (!w->spin)
> +			return;
> +
> +		/*
> +		 * The device may be gone (unbind/unplug), so avoid
> +		 * igt_spin_free(): on Xe it would wait forever on a syncobj
> +		 * that never signals; on i915 it would touch the dead fd via
> +		 * gem_munmap()/gem_close(). Instead, end the spinner via a
> +		 * userspace mmap write and let the DRM fd close reclaim the
> +		 * kernel-side resources.
> +		 */
> +		local_debug("%s\n", "stopping GPU spinner");
> +		igt_spin_end(w->spin);
> +		put_ahnd(w->ahnd);
> +		w->spin = NULL;
> +		w->ahnd = 0;
> +	}
> +}
> +
>  /* Subtests */
>  
>  static void unbind_rebind(struct hotunplug *priv)
> @@ -679,6 +753,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
>  	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
>  }
>  
> +static void hotunbind_rebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	driver_bind(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotunplug_rescan_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	bus_rescan(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
>  /* Main */
>  
>  int igt_main()
> @@ -817,6 +1035,78 @@ int igt_main()
>  			recover(&priv);
>  	}
>  
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
> +		igt_subtest("hotunbind-rebind-with-load")
> +			hotunbind_rebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
> +		igt_subtest("hotunplug-rescan-with-load")
> +			hotunplug_rescan_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
> +		igt_subtest("hotrebind-with-load")
> +			hotrebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
> +		igt_subtest("hotreplug-with-load")
> +			hotreplug_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotrebind-lateclose-with-load")
> +			hotrebind_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotreplug-lateclose-with-load")
> +			hotreplug_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
>  	igt_fixture() {
>  		post_healthcheck(&priv);
>  

[PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Nitin Gote]

The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
but leave the GPU idle, so the kernel hotplug path is never exercised
against an active workload.

Add six new dedicated *-with-load subtests that run a GPU spinner across
the unbind/unplug sequence so the device is removed while a workload is
actively using it.

The workload helpers use an explicit chipset dispatch block in
workload_start()/stop() so that other vendors can contribute
support by adding an else-if branch. New subtests are gated on
workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
and returns false (SKIP) on any other driver.

igt_spin_free() is avoided in workload_stop() since the device may be
gone by then -- igt_spin_end() writes the stop condition via a userspace
mmap and lets the DRM fd close reclaim kernel-side resources.

Validated on BMG and DG2 with a KASAN-enabled kernel:
all six new subtests pass with no KASAN reports.

v4: Rebase to latest igt.
    Also the failure seen with the new core_hotunplug "with-load"
    IGT subtests is fixed by kmd patch:
    https://patchwork.freedesktop.org/series/171989/

v3: Extend struct gpu_workload with a union of vendor-named members
    to match the chipset dispatch in workload_start()/stop(). (Janusz)

v2: Pass the hotunplug priv struct to workload_start()/stop()
    and dispatch via an explicit if/else-if chipset block to invite
    other vendors to contribute. (Janusz)

Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Reviewed-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
---
 tests/core_hotunplug.c | 294 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 294 insertions(+)

diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
index 33de65369..b11a4231b 100644
--- a/tests/core_hotunplug.c
+++ b/tests/core_hotunplug.c
@@ -80,6 +80,34 @@
  * SUBTEST: unplug-rescan
  * Description: Check if a device believed to be closed can be cleanly
  *		unplugged, then restored
+ *
+ * SUBTEST: hotunbind-rebind-with-load
+ * Description: Check if the driver can be cleanly unbound from an open device
+ *		with a background GPU workload in flight, then released and
+ *		rebound
+ *
+ * SUBTEST: hotunplug-rescan-with-load
+ * Description: Check if an open device with a background GPU workload in
+ *		flight can be cleanly unplugged, then released and restored
+ *
+ * SUBTEST: hotrebind-with-load
+ * Description: Check if the driver can be cleanly rebound to a device with a
+ *		still open hot unbound driver instance while a background GPU
+ *		workload is in flight
+ *
+ * SUBTEST: hotreplug-with-load
+ * Description: Check if a hot unplugged and still open device can be cleanly
+ *		restored while a background GPU workload is in flight
+ *
+ * SUBTEST: hotrebind-lateclose-with-load
+ * Description: Check if a hot unbound driver instance still open after hot
+ *		rebind with a background GPU workload in flight can be cleanly
+ *		released
+ *
+ * SUBTEST: hotreplug-lateclose-with-load
+ * Description: Check if an instance of a still open while hot replugged
+ *		device with a background GPU workload in flight can be cleanly
+ *		released
  */
 
 IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
@@ -550,6 +578,56 @@ static void post_healthcheck(struct hotunplug *priv)
 	cleanup(priv);
 }
 
+/* GPU workload helpers */
+
+struct gpu_workload {
+	union {
+		struct {
+			igt_spin_t *spin;
+			uint64_t ahnd;
+		} intel; /* Xe and i915 */
+	};
+};
+
+static bool workload_available(int chipset)
+{
+	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
+}
+
+static void workload_start(struct hotunplug *priv, int fd,
+			   struct gpu_workload *w)
+{
+	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
+		local_debug("%s\n", "starting GPU spinner");
+		priv->failure = "GPU workload start failure!";
+		w->intel.ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
+		w->intel.spin = igt_spin_new(fd, .ahnd = w->intel.ahnd);
+		priv->failure = NULL;
+	}
+}
+
+static void workload_stop(struct hotunplug *priv, struct gpu_workload *w)
+{
+	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
+		if (!w->intel.spin)
+			return;
+
+		/*
+		 * The device may be gone (unbind/unplug), so avoid
+		 * igt_spin_free(): on Xe it would wait forever on a syncobj
+		 * that never signals; on i915 it would touch the dead fd via
+		 * gem_munmap()/gem_close(). Instead, end the spinner via a
+		 * userspace mmap write and let the DRM fd close reclaim the
+		 * kernel-side resources.
+		 */
+		local_debug("%s\n", "stopping GPU spinner");
+		igt_spin_end(w->intel.spin);
+		put_ahnd(w->intel.ahnd);
+		w->intel.spin = NULL;
+		w->intel.ahnd = 0;
+	}
+}
+
 /* Subtests */
 
 static void unbind_rebind(struct hotunplug *priv)
@@ -664,6 +742,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
 	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
 }
 
+static void hotunbind_rebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	driver_bind(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotunplug_rescan_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	bus_rescan(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(priv, &w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(priv, &w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
 /* Main */
 
 int igt_main()
@@ -802,6 +1024,78 @@ int igt_main()
 			recover(&priv);
 	}
 
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
+		igt_subtest("hotunbind-rebind-with-load")
+			hotunbind_rebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
+		igt_subtest("hotunplug-rescan-with-load")
+			hotunplug_rescan_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
+		igt_subtest("hotrebind-with-load")
+			hotrebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
+		igt_subtest("hotreplug-with-load")
+			hotreplug_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotrebind-lateclose-with-load")
+			hotrebind_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotreplug-lateclose-with-load")
+			hotreplug_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
 	igt_fixture() {
 		post_healthcheck(&priv);
 
-- 
2.50.1

Re: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Janusz Krzysztofik]

Hi Nitin,

Good job, however, I think we still need some improvements.

On Fri, 2026-08-21 at 12:28 +0530, Nitin Gote wrote:
> The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
> but leave the GPU idle, so the kernel hotplug path is never exercised
> against an active workload.
> 
> Add six new dedicated *-with-load subtests that run a GPU spinner across
> the unbind/unplug sequence so the device is removed while a workload is
> actively using it.
> 
> The workload helpers use an explicit chipset dispatch block in
> workload_start()/stop() so that other vendors can contribute
> support by adding an else-if branch. New subtests are gated on
> workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
> and returns false (SKIP) on any other driver.
> 
> igt_spin_free() is avoided in workload_stop() since the device may be
> gone by then -- igt_spin_end() writes the stop condition via a userspace
> mmap and lets the DRM fd close reclaim kernel-side resources.
> 
> Validated on BMG and DG2 with a KASAN-enabled kernel:
> all six new subtests pass with no KASAN reports.
> 
> v4: Rebase to latest igt.
>     Also the failure seen with the new core_hotunplug "with-load"
>     IGT subtests is fixed by kmd patch:
>     https://patchwork.freedesktop.org/series/171989/
> 
> v3: Extend struct gpu_workload with a union of vendor-named members
>     to match the chipset dispatch in workload_start()/stop(). (Janusz)
> 
> v2: Pass the hotunplug priv struct to workload_start()/stop()
>     and dispatch via an explicit if/else-if chipset block to invite
>     other vendors to contribute. (Janusz)
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Reviewed-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
> ---
>  tests/core_hotunplug.c | 294 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 294 insertions(+)
> 
> diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
> index 33de65369..b11a4231b 100644
> --- a/tests/core_hotunplug.c
> +++ b/tests/core_hotunplug.c
> @@ -80,6 +80,34 @@
>   * SUBTEST: unplug-rescan
>   * Description: Check if a device believed to be closed can be cleanly
>   *		unplugged, then restored
> + *
> + * SUBTEST: hotunbind-rebind-with-load
> + * Description: Check if the driver can be cleanly unbound from an open device
> + *		with a background GPU workload in flight, then released and
> + *		rebound
> + *
> + * SUBTEST: hotunplug-rescan-with-load
> + * Description: Check if an open device with a background GPU workload in
> + *		flight can be cleanly unplugged, then released and restored
> + *
> + * SUBTEST: hotrebind-with-load
> + * Description: Check if the driver can be cleanly rebound to a device with a
> + *		still open hot unbound driver instance while a background GPU
> + *		workload is in flight
> + *
> + * SUBTEST: hotreplug-with-load
> + * Description: Check if a hot unplugged and still open device can be cleanly
> + *		restored while a background GPU workload is in flight
> + *
> + * SUBTEST: hotrebind-lateclose-with-load
> + * Description: Check if a hot unbound driver instance still open after hot
> + *		rebind with a background GPU workload in flight can be cleanly
> + *		released
> + *
> + * SUBTEST: hotreplug-lateclose-with-load
> + * Description: Check if an instance of a still open while hot replugged
> + *		device with a background GPU workload in flight can be cleanly
> + *		released
>   */
>  
>  IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
> @@ -550,6 +578,56 @@ static void post_healthcheck(struct hotunplug *priv)
>  	cleanup(priv);
>  }
>  
> +/* GPU workload helpers */
> +
> +struct gpu_workload {
> +	union {
> +		struct {
> +			igt_spin_t *spin;
> +			uint64_t ahnd;
> +		} intel; /* Xe and i915 */
> +	};
> +};
> +
> +static bool workload_available(int chipset)
> +{
> +	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;

NIT: I think a switch (chipset) { case DRIVER_XE: ... } construct, here 
and consequently below in workload_start/stop, could be more effective and 
more easily extendable with potential future additions from other vendors, 
but that can be refactored later, on a first such addition.

> +}
> +
> +static void workload_start(struct hotunplug *priv, int fd,
> +			   struct gpu_workload *w)
> +{
> +	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
> +		local_debug("%s\n", "starting GPU spinner");
> +		priv->failure = "GPU workload start failure!";
> +		w->intel.ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
> +		w->intel.spin = igt_spin_new(fd, .ahnd = w->intel.ahnd);
> +		priv->failure = NULL;
> +	}
> +}
> +
> +static void workload_stop(struct hotunplug *priv, struct gpu_workload *w)
> +{
> +	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
> +		if (!w->intel.spin)
> +			return;

Since igt_fail() can be called from inside igt_spin_new(), workload_start()
can fail leaving an open ahnd but no spin.  We need to handle that case.

> +
> +		/*
> +		 * The device may be gone (unbind/unplug), so avoid
> +		 * igt_spin_free(): on Xe it would wait forever on a syncobj
> +		 * that never signals; on i915 it would touch the dead fd via
> +		 * gem_munmap()/gem_close(). Instead, end the spinner via a
> +		 * userspace mmap write and let the DRM fd close reclaim the
> +		 * kernel-side resources.
> +		 */
> +		local_debug("%s\n", "stopping GPU spinner");
> +		igt_spin_end(w->intel.spin);
> +		put_ahnd(w->intel.ahnd);
> +		w->intel.spin = NULL;
> +		w->intel.ahnd = 0;
> +	}
> +}
> +
>  /* Subtests */
>  
>  static void unbind_rebind(struct hotunplug *priv)
> @@ -664,6 +742,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
>  	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
>  }
>  
> +static void hotunbind_rebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 0);

Since igt_fail() can be called from driver_unbind(), as well as from other 
functions called between workload_start() and workload_stop() in other 
subtests below, we need to address those cases to be on the safe side.
We could e.g.:
- embed struct gpu_workload inside struct hotunplug,
- extend cleanup() (or recover()) function with another workload_stop().

Thanks,
Janusz


> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	driver_bind(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotunplug_rescan_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	bus_rescan(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
>  /* Main */
>  
>  int igt_main()
> @@ -802,6 +1024,78 @@ int igt_main()
>  			recover(&priv);
>  	}
>  
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
> +		igt_subtest("hotunbind-rebind-with-load")
> +			hotunbind_rebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
> +		igt_subtest("hotunplug-rescan-with-load")
> +			hotunplug_rescan_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
> +		igt_subtest("hotrebind-with-load")
> +			hotrebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
> +		igt_subtest("hotreplug-with-load")
> +			hotreplug_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotrebind-lateclose-with-load")
> +			hotrebind_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotreplug-lateclose-with-load")
> +			hotreplug_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
>  	igt_fixture() {
>  		post_healthcheck(&priv);
>  

[PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Nitin Gote]

The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
but leave the GPU idle, so the kernel hotplug path is never exercised
against an active workload.

Add six new dedicated *-with-load subtests that run a GPU spinner across
the unbind/unplug sequence so the device is removed while a workload is
actively using it.

The workload helpers use an explicit chipset dispatch block in
workload_start()/stop() so that other vendors can contribute
support by adding an else-if branch. New subtests are gated on
workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
and returns false (SKIP) on any other driver.

igt_spin_free() is avoided in workload_stop() since the device may be
gone by then -- igt_spin_end() writes the stop condition via a userspace
mmap and lets the DRM fd close reclaim kernel-side resources.

Validated on BMG and DG2 with a KASAN-enabled kernel:
all six new subtests pass with no KASAN reports.

v3: Extend struct gpu_workload with a union of vendor-named members
    to match the chipset dispatch in workload_start()/stop(). (Janusz)

v2: Pass the hotunplug priv struct to workload_start()/stop()
    and dispatch via an explicit if/else-if chipset block to invite
    other vendors to contribute. (Janusz)

Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
---
Hi Janusz,

Extended the struct gpu_workload with a union of vendor-named members
to make a room for other vendors data.

Thanks,
Nitin

 tests/core_hotunplug.c | 294 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 294 insertions(+)

diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
index 7c9dae1bf..2c54af628 100644
--- a/tests/core_hotunplug.c
+++ b/tests/core_hotunplug.c
@@ -80,6 +80,34 @@
  * SUBTEST: unplug-rescan
  * Description: Check if a device believed to be closed can be cleanly
  *		unplugged, then restored
+ *
+ * SUBTEST: hotunbind-rebind-with-load
+ * Description: Check if the driver can be cleanly unbound from an open device
+ *		with a background GPU workload in flight, then released and
+ *		rebound
+ *
+ * SUBTEST: hotunplug-rescan-with-load
+ * Description: Check if an open device with a background GPU workload in
+ *		flight can be cleanly unplugged, then released and restored
+ *
+ * SUBTEST: hotrebind-with-load
+ * Description: Check if the driver can be cleanly rebound to a device with a
+ *		still open hot unbound driver instance while a background GPU
+ *		workload is in flight
+ *
+ * SUBTEST: hotreplug-with-load
+ * Description: Check if a hot unplugged and still open device can be cleanly
+ *		restored while a background GPU workload is in flight
+ *
+ * SUBTEST: hotrebind-lateclose-with-load
+ * Description: Check if a hot unbound driver instance still open after hot
+ *		rebind with a background GPU workload in flight can be cleanly
+ *		released
+ *
+ * SUBTEST: hotreplug-lateclose-with-load
+ * Description: Check if an instance of a still open while hot replugged
+ *		device with a background GPU workload in flight can be cleanly
+ *		released
  */
 
 IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
@@ -565,6 +593,56 @@ static void set_filter_from_device(int fd)
 	igt_assert_eq(igt_device_filter_add(filter), 1);
 }
 
+/* GPU workload helpers */
+
+struct gpu_workload {
+	union {
+		struct {
+			igt_spin_t *spin;
+			uint64_t ahnd;
+		} intel; /* Xe and i915 */
+	};
+};
+
+static bool workload_available(int chipset)
+{
+	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
+}
+
+static void workload_start(struct hotunplug *priv, int fd,
+			   struct gpu_workload *w)
+{
+	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
+		local_debug("%s\n", "starting GPU spinner");
+		priv->failure = "GPU workload start failure!";
+		w->intel.ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
+		w->intel.spin = igt_spin_new(fd, .ahnd = w->intel.ahnd);
+		priv->failure = NULL;
+	}
+}
+
+static void workload_stop(struct hotunplug *priv, struct gpu_workload *w)
+{
+	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
+		if (!w->intel.spin)
+			return;
+
+		/*
+		 * The device may be gone (unbind/unplug), so avoid
+		 * igt_spin_free(): on Xe it would wait forever on a syncobj
+		 * that never signals; on i915 it would touch the dead fd via
+		 * gem_munmap()/gem_close(). Instead, end the spinner via a
+		 * userspace mmap write and let the DRM fd close reclaim the
+		 * kernel-side resources.
+		 */
+		local_debug("%s\n", "stopping GPU spinner");
+		igt_spin_end(w->intel.spin);
+		put_ahnd(w->intel.ahnd);
+		w->intel.spin = NULL;
+		w->intel.ahnd = 0;
+	}
+}
+
 /* Subtests */
 
 static void unbind_rebind(struct hotunplug *priv)
@@ -679,6 +757,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
 	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
 }
 
+static void hotunbind_rebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	driver_bind(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotunplug_rescan_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	bus_rescan(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(priv, &w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(priv, &w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(priv, &w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
 /* Main */
 
 int igt_main()
@@ -817,6 +1039,78 @@ int igt_main()
 			recover(&priv);
 	}
 
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
+		igt_subtest("hotunbind-rebind-with-load")
+			hotunbind_rebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
+		igt_subtest("hotunplug-rescan-with-load")
+			hotunplug_rescan_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
+		igt_subtest("hotrebind-with-load")
+			hotrebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
+		igt_subtest("hotreplug-with-load")
+			hotreplug_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotrebind-lateclose-with-load")
+			hotrebind_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotreplug-lateclose-with-load")
+			hotreplug_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
 	igt_fixture() {
 		post_healthcheck(&priv);
 
-- 
2.50.1

Re: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Janusz Krzysztofik]

Hi Nitin,

On Mon, 2026-05-18 at 21:18 +0530, Nitin Gote wrote:
> The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
> but leave the GPU idle, so the kernel hotplug path is never exercised
> against an active workload.
> 
> Add six new dedicated *-with-load subtests that run a GPU spinner across
> the unbind/unplug sequence so the device is removed while a workload is
> actively using it.
> 
> The workload helpers use an explicit chipset dispatch block in
> workload_start()/stop() so that other vendors can contribute
> support by adding an else-if branch. New subtests are gated on
> workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
> and returns false (SKIP) on any other driver.
> 
> igt_spin_free() is avoided in workload_stop() since the device may be
> gone by then -- igt_spin_end() writes the stop condition via a userspace
> mmap and lets the DRM fd close reclaim kernel-side resources.
> 
> Validated on BMG and DG2 with a KASAN-enabled kernel:
> all six new subtests pass with no KASAN reports.
> 
> v3: Extend struct gpu_workload with a union of vendor-named members
>     to match the chipset dispatch in workload_start()/stop(). (Janusz)
> 
> v2: Pass the hotunplug priv struct to workload_start()/stop()
>     and dispatch via an explicit if/else-if chipset block to invite
>     other vendors to contribute. (Janusz)
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>

Now it LGTM.

Reviewed-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>


> ---
> Hi Janusz,
> 
> Extended the struct gpu_workload with a union of vendor-named members
> to make a room for other vendors data.
> 
> Thanks,
> Nitin
> 
>  tests/core_hotunplug.c | 294 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 294 insertions(+)
> 
> diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
> index 7c9dae1bf..2c54af628 100644
> --- a/tests/core_hotunplug.c
> +++ b/tests/core_hotunplug.c
> @@ -80,6 +80,34 @@
>   * SUBTEST: unplug-rescan
>   * Description: Check if a device believed to be closed can be cleanly
>   *		unplugged, then restored
> + *
> + * SUBTEST: hotunbind-rebind-with-load
> + * Description: Check if the driver can be cleanly unbound from an open device
> + *		with a background GPU workload in flight, then released and
> + *		rebound
> + *
> + * SUBTEST: hotunplug-rescan-with-load
> + * Description: Check if an open device with a background GPU workload in
> + *		flight can be cleanly unplugged, then released and restored
> + *
> + * SUBTEST: hotrebind-with-load
> + * Description: Check if the driver can be cleanly rebound to a device with a
> + *		still open hot unbound driver instance while a background GPU
> + *		workload is in flight
> + *
> + * SUBTEST: hotreplug-with-load
> + * Description: Check if a hot unplugged and still open device can be cleanly
> + *		restored while a background GPU workload is in flight
> + *
> + * SUBTEST: hotrebind-lateclose-with-load
> + * Description: Check if a hot unbound driver instance still open after hot
> + *		rebind with a background GPU workload in flight can be cleanly
> + *		released
> + *
> + * SUBTEST: hotreplug-lateclose-with-load
> + * Description: Check if an instance of a still open while hot replugged
> + *		device with a background GPU workload in flight can be cleanly
> + *		released
>   */
>  
>  IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
> @@ -565,6 +593,56 @@ static void set_filter_from_device(int fd)
>  	igt_assert_eq(igt_device_filter_add(filter), 1);
>  }
>  
> +/* GPU workload helpers */
> +
> +struct gpu_workload {
> +	union {
> +		struct {
> +			igt_spin_t *spin;
> +			uint64_t ahnd;
> +		} intel; /* Xe and i915 */
> +	};
> +};
> +
> +static bool workload_available(int chipset)
> +{
> +	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
> +}
> +
> +static void workload_start(struct hotunplug *priv, int fd,
> +			   struct gpu_workload *w)
> +{
> +	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
> +		local_debug("%s\n", "starting GPU spinner");
> +		priv->failure = "GPU workload start failure!";
> +		w->intel.ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
> +		w->intel.spin = igt_spin_new(fd, .ahnd = w->intel.ahnd);
> +		priv->failure = NULL;
> +	}
> +}
> +
> +static void workload_stop(struct hotunplug *priv, struct gpu_workload *w)
> +{
> +	if (priv->chipset == DRIVER_XE || priv->chipset == DRIVER_INTEL) {
> +		if (!w->intel.spin)
> +			return;
> +
> +		/*
> +		 * The device may be gone (unbind/unplug), so avoid
> +		 * igt_spin_free(): on Xe it would wait forever on a syncobj
> +		 * that never signals; on i915 it would touch the dead fd via
> +		 * gem_munmap()/gem_close(). Instead, end the spinner via a
> +		 * userspace mmap write and let the DRM fd close reclaim the
> +		 * kernel-side resources.
> +		 */
> +		local_debug("%s\n", "stopping GPU spinner");
> +		igt_spin_end(w->intel.spin);
> +		put_ahnd(w->intel.ahnd);
> +		w->intel.spin = NULL;
> +		w->intel.ahnd = 0;
> +	}
> +}
> +
>  /* Subtests */
>  
>  static void unbind_rebind(struct hotunplug *priv)
> @@ -679,6 +757,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
>  	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
>  }
>  
> +static void hotunbind_rebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	driver_bind(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotunplug_rescan_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	bus_rescan(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(priv, &w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
>  /* Main */
>  
>  int igt_main()
> @@ -817,6 +1039,78 @@ int igt_main()
>  			recover(&priv);
>  	}
>  
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
> +		igt_subtest("hotunbind-rebind-with-load")
> +			hotunbind_rebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
> +		igt_subtest("hotunplug-rescan-with-load")
> +			hotunplug_rescan_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
> +		igt_subtest("hotrebind-with-load")
> +			hotrebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
> +		igt_subtest("hotreplug-with-load")
> +			hotreplug_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotrebind-lateclose-with-load")
> +			hotrebind_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotreplug-lateclose-with-load")
> +			hotreplug_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
>  	igt_fixture() {
>  		post_healthcheck(&priv);
>  

Re: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Kamil Konieczny]

Hi Nitin,
On 2026-05-18 at 21:18:09 +0530, Nitin Gote wrote:
> The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
> but leave the GPU idle, so the kernel hotplug path is never exercised
> against an active workload.
> 
> Add six new dedicated *-with-load subtests that run a GPU spinner across
> the unbind/unplug sequence so the device is removed while a workload is
> actively using it.
> 
> The workload helpers use an explicit chipset dispatch block in
> workload_start()/stop() so that other vendors can contribute
> support by adding an else-if branch. New subtests are gated on
> workload_available(), which currently covers DRIVER_XE and DRIVER_INTEL,
> and returns false (SKIP) on any other driver.
> 
> igt_spin_free() is avoided in workload_stop() since the device may be
> gone by then -- igt_spin_end() writes the stop condition via a userspace
> mmap and lets the DRM fd close reclaim kernel-side resources.
> 
> Validated on BMG and DG2 with a KASAN-enabled kernel:
> all six new subtests pass with no KASAN reports.

Please reply to Xe.FULL CI failure with cc to CI-bug filling team.
There are few fails from these new ones. Also please cut reply
after 'Known failures' to keep mail short.

Regards,
Kamil

> 
> v3: Extend struct gpu_workload with a union of vendor-named members
>     to match the chipset dispatch in workload_start()/stop(). (Janusz)
> 
> v2: Pass the hotunplug priv struct to workload_start()/stop()
>     and dispatch via an explicit if/else-if chipset block to invite
>     other vendors to contribute. (Janusz)
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
> ---
> Hi Janusz,
> 
> Extended the struct gpu_workload with a union of vendor-named members
> to make a room for other vendors data.
> 
> Thanks,
> Nitin
> 
>  tests/core_hotunplug.c | 294 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 294 insertions(+)
> 
> diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
> index 7c9dae1bf..2c54af628 100644
> --- a/tests/core_hotunplug.c
> +++ b/tests/core_hotunplug.c
> @@ -80,6 +80,34 @@
>   * SUBTEST: unplug-rescan
>   * Description: Check if a device believed to be closed can be cleanly
>   *		unplugged, then restored
> + *
> + * SUBTEST: hotunbind-rebind-with-load
> + * Description: Check if the driver can be cleanly unbound from an open device
> + *		with a background GPU workload in flight, then released and
> + *		rebound
> + *
> + * SUBTEST: hotunplug-rescan-with-load
> + * Description: Check if an open device with a background GPU workload in
> + *		flight can be cleanly unplugged, then released and restored
> + *
> + * SUBTEST: hotrebind-with-load
> + * Description: Check if the driver can be cleanly rebound to a device with a
> + *		still open hot unbound driver instance while a background GPU
> + *		workload is in flight
> + *
> + * SUBTEST: hotreplug-with-load
> + * Description: Check if a hot unplugged and still open device can be cleanly
> + *		restored while a background GPU workload is in flight
> + *
> + * SUBTEST: hotrebind-lateclose-with-load
> + * Description: Check if a hot unbound driver instance still open after hot
> + *		rebind with a background GPU workload in flight can be cleanly
> + *		released
> + *
> + * SUBTEST: hotreplug-lateclose-with-load
> + * Description: Check if an instance of a still open while hot replugged
> + *		device with a background GPU workload in flight can be cleanly
> + *		released
>   */
>  
>  IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
[cut]

[PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Nitin Gote]

The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
but leave the GPU idle, so the kernel hotplug path is never exercised
against an active VM, exec queue and BOs.

Add six new dedicated *-with-load subtests that run a GPU spinner across
the unbind/unplug sequence so the device is removed while a workload is
actively using it.

The workload helpers are driver-agnostic: igt_spin_new() dispatches
transparently for both Xe and i915. New subtests are gated on
workload_available(), which covers DRIVER_XE and DRIVER_INTEL, and
returns false (SKIP) on any other driver.

igt_spin_free() is avoided in workload_stop() since the device may be
gone by then — igt_spin_end() writes the stop condition via a userspace
mmap and lets the DRM fd close reclaim kernel-side resources.

Validated on BMG and DG2 with a KASAN-enabled kernel:
all six new subtests pass with no KASAN reports.

Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
Assisted-by: Copilot:claude-opus-4.7
Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
---
Hi Janusz/Kamil,
I have introduced new subtests as per review comments in
https://patchwork.freedesktop.org/series/166056/ 
instead of modifying existing ones to avoid changing their scope.
Also used driver-agnostic helper names throughout.

Thanks,
Nitin


 tests/core_hotunplug.c | 285 +++++++++++++++++++++++++++++++++++++++++
 1 file changed, 285 insertions(+)

diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
index 7c9dae1bf..85a96294e 100644
--- a/tests/core_hotunplug.c
+++ b/tests/core_hotunplug.c
@@ -80,6 +80,34 @@
  * SUBTEST: unplug-rescan
  * Description: Check if a device believed to be closed can be cleanly
  *		unplugged, then restored
+ *
+ * SUBTEST: hotunbind-rebind-with-load
+ * Description: Check if the driver can be cleanly unbound from an open device
+ *		with a background GPU workload in flight, then released and
+ *		rebound
+ *
+ * SUBTEST: hotunplug-rescan-with-load
+ * Description: Check if an open device with a background GPU workload in
+ *		flight can be cleanly unplugged, then released and restored
+ *
+ * SUBTEST: hotrebind-with-load
+ * Description: Check if the driver can be cleanly rebound to a device with a
+ *		still open hot unbound driver instance while a background GPU
+ *		workload is in flight
+ *
+ * SUBTEST: hotreplug-with-load
+ * Description: Check if a hot unplugged and still open device can be cleanly
+ *		restored while a background GPU workload is in flight
+ *
+ * SUBTEST: hotrebind-lateclose-with-load
+ * Description: Check if a hot unbound driver instance still open after hot
+ *		rebind with a background GPU workload in flight can be cleanly
+ *		released
+ *
+ * SUBTEST: hotreplug-lateclose-with-load
+ * Description: Check if an instance of a still open while hot replugged
+ *		device with a background GPU workload in flight can be cleanly
+ *		released
  */
 
 IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
@@ -565,6 +593,47 @@ static void set_filter_from_device(int fd)
 	igt_assert_eq(igt_device_filter_add(filter), 1);
 }
 
+/* GPU workload helpers */
+
+struct gpu_workload {
+	igt_spin_t *spin;
+	uint64_t ahnd;
+};
+
+static bool workload_available(int chipset)
+{
+	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
+}
+
+static void workload_start(struct hotunplug *priv, int fd,
+			   struct gpu_workload *w)
+{
+	local_debug("%s\n", "starting GPU spinner");
+	priv->failure = "GPU workload start failure!";
+	w->ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
+	w->spin = igt_spin_new(fd, .ahnd = w->ahnd);
+	priv->failure = NULL;
+}
+
+static void workload_stop(struct gpu_workload *w)
+{
+	if (!w->spin)
+		return;
+
+	/*
+	 * The device may be gone (unbind/unplug), so avoid igt_spin_free():
+	 * on Xe it would wait forever on a syncobj that never signals; on i915
+	 * it would touch the dead fd via gem_munmap()/gem_close(). Instead, end
+	 * the spinner via a userspace mmap write and let the DRM fd close
+	 * reclaim the kernel-side resources.
+	 */
+	local_debug("%s\n", "stopping GPU spinner");
+	igt_spin_end(w->spin);
+	put_ahnd(w->ahnd);
+	w->spin = NULL;
+	w->ahnd = 0;
+}
+
 /* Subtests */
 
 static void unbind_rebind(struct hotunplug *priv)
@@ -679,6 +748,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
 	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
 }
 
+static void hotunbind_rebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 0);
+
+	workload_stop(&w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	driver_bind(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotunplug_rescan_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 0);
+
+	workload_stop(&w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	bus_rescan(priv, 0);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(&w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(&w);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotrebind_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	driver_unbind(priv, "hot ", 60);
+
+	driver_bind(priv, 0);
+
+	workload_stop(&w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
+static void hotreplug_lateclose_with_load(struct hotunplug *priv)
+{
+	struct gpu_workload w = { 0 };
+
+	pre_check(priv);
+
+	igt_require_f(workload_available(priv->chipset),
+		      "No GPU workload support for this driver\n");
+
+	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
+
+	workload_start(priv, priv->fd.drm, &w);
+
+	device_unplug(priv, "hot ", 60);
+
+	bus_rescan(priv, 0);
+
+	workload_stop(&w);
+
+	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
+	igt_assert_eq(priv->fd.drm, -1);
+
+	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
+}
+
 /* Main */
 
 int igt_main()
@@ -817,6 +1030,78 @@ int igt_main()
 			recover(&priv);
 	}
 
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
+		igt_subtest("hotunbind-rebind-with-load")
+			hotunbind_rebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
+		igt_subtest("hotunplug-rescan-with-load")
+			hotunplug_rescan_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
+		igt_subtest("hotrebind-with-load")
+			hotrebind_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
+		igt_subtest("hotreplug-with-load")
+			hotreplug_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotrebind-lateclose-with-load")
+			hotrebind_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
+	igt_fixture()
+		post_healthcheck(&priv);
+
+	igt_subtest_group() {
+		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
+		igt_subtest("hotreplug-lateclose-with-load")
+			hotreplug_lateclose_with_load(&priv);
+
+		igt_fixture()
+			recover(&priv);
+	}
+
 	igt_fixture() {
 		post_healthcheck(&priv);
 
-- 
2.50.1

Re: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Janusz Krzysztofik]

Hi Nitin,

On Mon, 2026-05-18 at 13:57 +0530, Nitin Gote wrote:
> The six fd-holding hot* subtests keep a DRM fd open across unbind/unplug
> but leave the GPU idle, so the kernel hotplug path is never exercised
> against an active VM, exec queue and BOs.
> 
> Add six new dedicated *-with-load subtests that run a GPU spinner across
> the unbind/unplug sequence so the device is removed while a workload is
> actively using it.
> 
> The workload helpers are driver-agnostic: igt_spin_new() dispatches
> transparently for both Xe and i915. New subtests are gated on
> workload_available(), which covers DRIVER_XE and DRIVER_INTEL, and
> returns false (SKIP) on any other driver.

While that's a good idea to skip early, I'd still pass the chipset argument
to workload_start/end() and process it with a case or if block that calls
vendor specific workload functions.  That way we invite other vendors to
contribute to this test instead of creating their own implementations.

Thanks,
Janusz

> 
> igt_spin_free() is avoided in workload_stop() since the device may be
> gone by then — igt_spin_end() writes the stop condition via a userspace
> mmap and lets the DRM fd close reclaim kernel-side resources.
> 
> Validated on BMG and DG2 with a KASAN-enabled kernel:
> all six new subtests pass with no KASAN reports.
> 
> Cc: Matthew Auld <matthew.auld@intel.com>
> Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> Assisted-by: Copilot:claude-opus-4.7
> Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
> ---
> Hi Janusz/Kamil,
> I have introduced new subtests as per review comments in
> https://patchwork.freedesktop.org/series/166056/ 
> instead of modifying existing ones to avoid changing their scope.
> Also used driver-agnostic helper names throughout.
> 
> Thanks,
> Nitin
> 
> 
>  tests/core_hotunplug.c | 285 +++++++++++++++++++++++++++++++++++++++++
>  1 file changed, 285 insertions(+)
> 
> diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
> index 7c9dae1bf..85a96294e 100644
> --- a/tests/core_hotunplug.c
> +++ b/tests/core_hotunplug.c
> @@ -80,6 +80,34 @@
>   * SUBTEST: unplug-rescan
>   * Description: Check if a device believed to be closed can be cleanly
>   *		unplugged, then restored
> + *
> + * SUBTEST: hotunbind-rebind-with-load
> + * Description: Check if the driver can be cleanly unbound from an open device
> + *		with a background GPU workload in flight, then released and
> + *		rebound
> + *
> + * SUBTEST: hotunplug-rescan-with-load
> + * Description: Check if an open device with a background GPU workload in
> + *		flight can be cleanly unplugged, then released and restored
> + *
> + * SUBTEST: hotrebind-with-load
> + * Description: Check if the driver can be cleanly rebound to a device with a
> + *		still open hot unbound driver instance while a background GPU
> + *		workload is in flight
> + *
> + * SUBTEST: hotreplug-with-load
> + * Description: Check if a hot unplugged and still open device can be cleanly
> + *		restored while a background GPU workload is in flight
> + *
> + * SUBTEST: hotrebind-lateclose-with-load
> + * Description: Check if a hot unbound driver instance still open after hot
> + *		rebind with a background GPU workload in flight can be cleanly
> + *		released
> + *
> + * SUBTEST: hotreplug-lateclose-with-load
> + * Description: Check if an instance of a still open while hot replugged
> + *		device with a background GPU workload in flight can be cleanly
> + *		released
>   */
>  
>  IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot unplug");
> @@ -565,6 +593,47 @@ static void set_filter_from_device(int fd)
>  	igt_assert_eq(igt_device_filter_add(filter), 1);
>  }
>  
> +/* GPU workload helpers */
> +
> +struct gpu_workload {
> +	igt_spin_t *spin;
> +	uint64_t ahnd;
> +};
> +
> +static bool workload_available(int chipset)
> +{
> +	return chipset == DRIVER_XE || chipset == DRIVER_INTEL;
> +}
> +
> +static void workload_start(struct hotunplug *priv, int fd,
> +			   struct gpu_workload *w)
> +{
> +	local_debug("%s\n", "starting GPU spinner");
> +	priv->failure = "GPU workload start failure!";
> +	w->ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
> +	w->spin = igt_spin_new(fd, .ahnd = w->ahnd);
> +	priv->failure = NULL;
> +}
> +
> +static void workload_stop(struct gpu_workload *w)
> +{
> +	if (!w->spin)
> +		return;
> +
> +	/*
> +	 * The device may be gone (unbind/unplug), so avoid igt_spin_free():
> +	 * on Xe it would wait forever on a syncobj that never signals; on i915
> +	 * it would touch the dead fd via gem_munmap()/gem_close(). Instead, end
> +	 * the spinner via a userspace mmap write and let the DRM fd close
> +	 * reclaim the kernel-side resources.
> +	 */
> +	local_debug("%s\n", "stopping GPU spinner");
> +	igt_spin_end(w->spin);
> +	put_ahnd(w->ahnd);
> +	w->spin = NULL;
> +	w->ahnd = 0;
> +}
> +
>  /* Subtests */
>  
>  static void unbind_rebind(struct hotunplug *priv)
> @@ -679,6 +748,150 @@ static void hotreplug_lateclose(struct hotunplug *priv)
>  	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
>  }
>  
> +static void hotunbind_rebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 0);
> +
> +	workload_stop(&w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	driver_bind(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotunplug_rescan_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 0);
> +
> +	workload_stop(&w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	bus_rescan(priv, 0);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(&w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(&w);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotrebind_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	driver_unbind(priv, "hot ", 60);
> +
> +	driver_bind(priv, 0);
> +
> +	workload_stop(&w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
> +static void hotreplug_lateclose_with_load(struct hotunplug *priv)
> +{
> +	struct gpu_workload w = { 0 };
> +
> +	pre_check(priv);
> +
> +	igt_require_f(workload_available(priv->chipset),
> +		      "No GPU workload support for this driver\n");
> +
> +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> +
> +	workload_start(priv, priv->fd.drm, &w);
> +
> +	device_unplug(priv, "hot ", 60);
> +
> +	bus_rescan(priv, 0);
> +
> +	workload_stop(&w);
> +
> +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> +	igt_assert_eq(priv->fd.drm, -1);
> +
> +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);
> +}
> +
>  /* Main */
>  
>  int igt_main()
> @@ -817,6 +1030,78 @@ int igt_main()
>  			recover(&priv);
>  	}
>  
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly unbound from an open device with a background GPU workload in flight, then released and rebound");
> +		igt_subtest("hotunbind-rebind-with-load")
> +			hotunbind_rebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an open device with a background GPU workload in flight can be cleanly unplugged, then released and restored");
> +		igt_subtest("hotunplug-rescan-with-load")
> +			hotunplug_rescan_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if the driver can be cleanly rebound to a device with a still open hot unbound driver instance while a background GPU workload is in flight");
> +		igt_subtest("hotrebind-with-load")
> +			hotrebind_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unplugged and still open device can be cleanly restored while a background GPU workload is in flight");
> +		igt_subtest("hotreplug-with-load")
> +			hotreplug_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if a hot unbound driver instance still open after hot rebind with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotrebind-lateclose-with-load")
> +			hotrebind_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
> +	igt_fixture()
> +		post_healthcheck(&priv);
> +
> +	igt_subtest_group() {
> +		igt_describe("Check if an instance of a still open while hot replugged device with a background GPU workload in flight can be cleanly released");
> +		igt_subtest("hotreplug-lateclose-with-load")
> +			hotreplug_lateclose_with_load(&priv);
> +
> +		igt_fixture()
> +			recover(&priv);
> +	}
> +
>  	igt_fixture() {
>  		post_healthcheck(&priv);
>  

RE: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising GPU workload during hotplug

[Gote, Nitin R]

Hi Janusz,

> -----Original Message-----
> From: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> Sent: Monday, May 18, 2026 2:18 PM
> To: Gote, Nitin R <nitin.r.gote@intel.com>; igt-dev@lists.freedesktop.org;
> kamil.konieczny@linux.intel.com
> Cc: Auld, Matthew <matthew.auld@intel.com>
> Subject: Re: [PATCH] tests/core_hotunplug: add *-with-load subtests exercising
> GPU workload during hotplug
> 
> Hi Nitin,
> 
> On Mon, 2026-05-18 at 13:57 +0530, Nitin Gote wrote:
> > The six fd-holding hot* subtests keep a DRM fd open across
> > unbind/unplug but leave the GPU idle, so the kernel hotplug path is
> > never exercised against an active VM, exec queue and BOs.
> >
> > Add six new dedicated *-with-load subtests that run a GPU spinner
> > across the unbind/unplug sequence so the device is removed while a
> > workload is actively using it.
> >
> > The workload helpers are driver-agnostic: igt_spin_new() dispatches
> > transparently for both Xe and i915. New subtests are gated on
> > workload_available(), which covers DRIVER_XE and DRIVER_INTEL, and
> > returns false (SKIP) on any other driver.
> 
> While that's a good idea to skip early, I'd still pass the chipset argument to
> workload_start/end() and process it with a case or if block that calls vendor
> specific workload functions.  That way we invite other vendors to contribute to
> this test instead of creating their own implementations.
> 

Good point. Thanks, will fix in new version.

- Nitin

> Thanks,
> Janusz
> 
> >
> > igt_spin_free() is avoided in workload_stop() since the device may be
> > gone by then — igt_spin_end() writes the stop condition via a
> > userspace mmap and lets the DRM fd close reclaim kernel-side resources.
> >
> > Validated on BMG and DG2 with a KASAN-enabled kernel:
> > all six new subtests pass with no KASAN reports.
> >
> > Cc: Matthew Auld <matthew.auld@intel.com>
> > Cc: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
> > Cc: Kamil Konieczny <kamil.konieczny@linux.intel.com>
> > Assisted-by: Copilot:claude-opus-4.7
> > Signed-off-by: Nitin Gote <nitin.r.gote@intel.com>
> > ---
> > Hi Janusz/Kamil,
> > I have introduced new subtests as per review comments in
> > https://patchwork.freedesktop.org/series/166056/
> > instead of modifying existing ones to avoid changing their scope.
> > Also used driver-agnostic helper names throughout.
> >
> > Thanks,
> > Nitin
> >
> >
> >  tests/core_hotunplug.c | 285
> > +++++++++++++++++++++++++++++++++++++++++
> >  1 file changed, 285 insertions(+)
> >
> > diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c index
> > 7c9dae1bf..85a96294e 100644
> > --- a/tests/core_hotunplug.c
> > +++ b/tests/core_hotunplug.c
> > @@ -80,6 +80,34 @@
> >   * SUBTEST: unplug-rescan
> >   * Description: Check if a device believed to be closed can be cleanly
> >   *		unplugged, then restored
> > + *
> > + * SUBTEST: hotunbind-rebind-with-load
> > + * Description: Check if the driver can be cleanly unbound from an open device
> > + *		with a background GPU workload in flight, then released and
> > + *		rebound
> > + *
> > + * SUBTEST: hotunplug-rescan-with-load
> > + * Description: Check if an open device with a background GPU workload in
> > + *		flight can be cleanly unplugged, then released and restored
> > + *
> > + * SUBTEST: hotrebind-with-load
> > + * Description: Check if the driver can be cleanly rebound to a device with a
> > + *		still open hot unbound driver instance while a background GPU
> > + *		workload is in flight
> > + *
> > + * SUBTEST: hotreplug-with-load
> > + * Description: Check if a hot unplugged and still open device can be cleanly
> > + *		restored while a background GPU workload is in flight
> > + *
> > + * SUBTEST: hotrebind-lateclose-with-load
> > + * Description: Check if a hot unbound driver instance still open after hot
> > + *		rebind with a background GPU workload in flight can be cleanly
> > + *		released
> > + *
> > + * SUBTEST: hotreplug-lateclose-with-load
> > + * Description: Check if an instance of a still open while hot replugged
> > + *		device with a background GPU workload in flight can be cleanly
> > + *		released
> >   */
> >
> >  IGT_TEST_DESCRIPTION("Examine behavior of a driver on device hot
> > unplug"); @@ -565,6 +593,47 @@ static void set_filter_from_device(int fd)
> >  	igt_assert_eq(igt_device_filter_add(filter), 1);  }
> >
> > +/* GPU workload helpers */
> > +
> > +struct gpu_workload {
> > +	igt_spin_t *spin;
> > +	uint64_t ahnd;
> > +};
> > +
> > +static bool workload_available(int chipset) {
> > +	return chipset == DRIVER_XE || chipset == DRIVER_INTEL; }
> > +
> > +static void workload_start(struct hotunplug *priv, int fd,
> > +			   struct gpu_workload *w)
> > +{
> > +	local_debug("%s\n", "starting GPU spinner");
> > +	priv->failure = "GPU workload start failure!";
> > +	w->ahnd = intel_allocator_open(fd, 0, INTEL_ALLOCATOR_RELOC);
> > +	w->spin = igt_spin_new(fd, .ahnd = w->ahnd);
> > +	priv->failure = NULL;
> > +}
> > +
> > +static void workload_stop(struct gpu_workload *w) {
> > +	if (!w->spin)
> > +		return;
> > +
> > +	/*
> > +	 * The device may be gone (unbind/unplug), so avoid igt_spin_free():
> > +	 * on Xe it would wait forever on a syncobj that never signals; on i915
> > +	 * it would touch the dead fd via gem_munmap()/gem_close(). Instead,
> end
> > +	 * the spinner via a userspace mmap write and let the DRM fd close
> > +	 * reclaim the kernel-side resources.
> > +	 */
> > +	local_debug("%s\n", "stopping GPU spinner");
> > +	igt_spin_end(w->spin);
> > +	put_ahnd(w->ahnd);
> > +	w->spin = NULL;
> > +	w->ahnd = 0;
> > +}
> > +
> >  /* Subtests */
> >
> >  static void unbind_rebind(struct hotunplug *priv) @@ -679,6 +748,150
> > @@ static void hotreplug_lateclose(struct hotunplug *priv)
> >  	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure);  }
> >
> > +static void hotunbind_rebind_with_load(struct hotunplug *priv) {
> > +	struct gpu_workload w = { 0 };
> > +
> > +	pre_check(priv);
> > +
> > +	igt_require_f(workload_available(priv->chipset),
> > +		      "No GPU workload support for this driver\n");
> > +
> > +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unbind");
> > +
> > +	workload_start(priv, priv->fd.drm, &w);
> > +
> > +	driver_unbind(priv, "hot ", 0);
> > +
> > +	workload_stop(&w);
> > +
> > +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> > +	igt_assert_eq(priv->fd.drm, -1);
> > +
> > +	driver_bind(priv, 0);
> > +
> > +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure); }
> > +
> > +static void hotunplug_rescan_with_load(struct hotunplug *priv) {
> > +	struct gpu_workload w = { 0 };
> > +
> > +	pre_check(priv);
> > +
> > +	igt_require_f(workload_available(priv->chipset),
> > +		      "No GPU workload support for this driver\n");
> > +
> > +	priv->fd.drm = local_drm_open_driver(false, "", " for hot unplug");
> > +
> > +	workload_start(priv, priv->fd.drm, &w);
> > +
> > +	device_unplug(priv, "hot ", 0);
> > +
> > +	workload_stop(&w);
> > +
> > +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> > +	igt_assert_eq(priv->fd.drm, -1);
> > +
> > +	bus_rescan(priv, 0);
> > +
> > +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure); }
> > +
> > +static void hotrebind_with_load(struct hotunplug *priv) {
> > +	struct gpu_workload w = { 0 };
> > +
> > +	pre_check(priv);
> > +
> > +	igt_require_f(workload_available(priv->chipset),
> > +		      "No GPU workload support for this driver\n");
> > +
> > +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> > +
> > +	workload_start(priv, priv->fd.drm, &w);
> > +
> > +	driver_unbind(priv, "hot ", 60);
> > +
> > +	driver_bind(priv, 0);
> > +
> > +	workload_stop(&w);
> > +
> > +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure); }
> > +
> > +static void hotreplug_with_load(struct hotunplug *priv) {
> > +	struct gpu_workload w = { 0 };
> > +
> > +	pre_check(priv);
> > +
> > +	igt_require_f(workload_available(priv->chipset),
> > +		      "No GPU workload support for this driver\n");
> > +
> > +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> > +
> > +	workload_start(priv, priv->fd.drm, &w);
> > +
> > +	device_unplug(priv, "hot ", 60);
> > +
> > +	bus_rescan(priv, 0);
> > +
> > +	workload_stop(&w);
> > +
> > +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure); }
> > +
> > +static void hotrebind_lateclose_with_load(struct hotunplug *priv) {
> > +	struct gpu_workload w = { 0 };
> > +
> > +	pre_check(priv);
> > +
> > +	igt_require_f(workload_available(priv->chipset),
> > +		      "No GPU workload support for this driver\n");
> > +
> > +	priv->fd.drm = local_drm_open_driver(false, "", " for hot rebind");
> > +
> > +	workload_start(priv, priv->fd.drm, &w);
> > +
> > +	driver_unbind(priv, "hot ", 60);
> > +
> > +	driver_bind(priv, 0);
> > +
> > +	workload_stop(&w);
> > +
> > +	priv->fd.drm = close_device(priv->fd.drm, "late ", "unbound ");
> > +	igt_assert_eq(priv->fd.drm, -1);
> > +
> > +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure); }
> > +
> > +static void hotreplug_lateclose_with_load(struct hotunplug *priv) {
> > +	struct gpu_workload w = { 0 };
> > +
> > +	pre_check(priv);
> > +
> > +	igt_require_f(workload_available(priv->chipset),
> > +		      "No GPU workload support for this driver\n");
> > +
> > +	priv->fd.drm = local_drm_open_driver(false, "", " for hot replug");
> > +
> > +	workload_start(priv, priv->fd.drm, &w);
> > +
> > +	device_unplug(priv, "hot ", 60);
> > +
> > +	bus_rescan(priv, 0);
> > +
> > +	workload_stop(&w);
> > +
> > +	priv->fd.drm = close_device(priv->fd.drm, "late ", "removed ");
> > +	igt_assert_eq(priv->fd.drm, -1);
> > +
> > +	igt_assert_f(healthcheck(priv, false), "%s\n", priv->failure); }
> > +
> >  /* Main */
> >
> >  int igt_main()
> > @@ -817,6 +1030,78 @@ int igt_main()
> >  			recover(&priv);
> >  	}
> >
> > +	igt_fixture()
> > +		post_healthcheck(&priv);
> > +
> > +	igt_subtest_group() {
> > +		igt_describe("Check if the driver can be cleanly unbound from an
> open device with a background GPU workload in flight, then released and
> rebound");
> > +		igt_subtest("hotunbind-rebind-with-load")
> > +			hotunbind_rebind_with_load(&priv);
> > +
> > +		igt_fixture()
> > +			recover(&priv);
> > +	}
> > +
> > +	igt_fixture()
> > +		post_healthcheck(&priv);
> > +
> > +	igt_subtest_group() {
> > +		igt_describe("Check if an open device with a background GPU
> workload in flight can be cleanly unplugged, then released and restored");
> > +		igt_subtest("hotunplug-rescan-with-load")
> > +			hotunplug_rescan_with_load(&priv);
> > +
> > +		igt_fixture()
> > +			recover(&priv);
> > +	}
> > +
> > +	igt_fixture()
> > +		post_healthcheck(&priv);
> > +
> > +	igt_subtest_group() {
> > +		igt_describe("Check if the driver can be cleanly rebound to a
> device with a still open hot unbound driver instance while a background GPU
> workload is in flight");
> > +		igt_subtest("hotrebind-with-load")
> > +			hotrebind_with_load(&priv);
> > +
> > +		igt_fixture()
> > +			recover(&priv);
> > +	}
> > +
> > +	igt_fixture()
> > +		post_healthcheck(&priv);
> > +
> > +	igt_subtest_group() {
> > +		igt_describe("Check if a hot unplugged and still open device can
> be cleanly restored while a background GPU workload is in flight");
> > +		igt_subtest("hotreplug-with-load")
> > +			hotreplug_with_load(&priv);
> > +
> > +		igt_fixture()
> > +			recover(&priv);
> > +	}
> > +
> > +	igt_fixture()
> > +		post_healthcheck(&priv);
> > +
> > +	igt_subtest_group() {
> > +		igt_describe("Check if a hot unbound driver instance still open
> after hot rebind with a background GPU workload in flight can be cleanly
> released");
> > +		igt_subtest("hotrebind-lateclose-with-load")
> > +			hotrebind_lateclose_with_load(&priv);
> > +
> > +		igt_fixture()
> > +			recover(&priv);
> > +	}
> > +
> > +	igt_fixture()
> > +		post_healthcheck(&priv);
> > +
> > +	igt_subtest_group() {
> > +		igt_describe("Check if an instance of a still open while hot
> replugged device with a background GPU workload in flight can be cleanly
> released");
> > +		igt_subtest("hotreplug-lateclose-with-load")
> > +			hotreplug_lateclose_with_load(&priv);
> > +
> > +		igt_fixture()
> > +			recover(&priv);
> > +	}
> > +
> >  	igt_fixture() {
> >  		post_healthcheck(&priv);
> >