[igt-dev] [PATCH i-g-t v6 6/9] lib/igt_kmod: make it less pedantic with audio driver removal

[Mauro Carvalho Chehab]

From: Mauro Carvalho Chehab <mchehab at kernel.org>

Current Linux Kernel don't report if the audio driver binds
into the DRM driver. As this is CPU specific, allow audio
driver unload fail without skipping the IGT tests on legacy
Kernels, as this may not be mandatory.

On new kernels where lsmod will properly display the dependency
between the audio and DRM drivers, skip the core hotunplug
test if it fails to unload the audio driver, as this is
unrelated to the DRM driver - and it could simply because there
are some userspace code using the audio device while the IGT
test is running.

Reviewed-by Jonathan Cavitt <jonathan.cavitt at intel.com>
Reviewed-by: Andi Shyti <andi.shyti at linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab at kernel.org>
---
 lib/igt_kmod.c         | 31 +++++++++++++++++++++++++++----
 tests/core_hotunplug.c |  7 ++-----
 2 files changed, 29 insertions(+), 9 deletions(-)

diff --git a/lib/igt_kmod.c b/lib/igt_kmod.c
index 9bb2fc705eb8..5d358c899cfb 100644
--- a/lib/igt_kmod.c
+++ b/lib/igt_kmod.c
@@ -408,18 +408,34 @@ static int igt_always_unload_audio_driver(char **who)
 		NULL,
 	};
 
+	/*
+	 * With old Kernels, the dependencies between audio and DRM drivers
+	 * are not shown. So, it may not be mandatory to remove the audio
+	 * driver before unload/unbind the DRM one. So, let's print warnings,
+	 * but return 0 on errors, as, if the dependency is mandatory, this
+	 * will be detected later when trying to unbind/unload the DRM driver.
+	 */
 	for (const char **m = sound; *m; m++) {
 		if (igt_kmod_is_loaded(*m)) {
 			if (who)
 				*who = strdup_realloc(*who, *m);
 
-			if (igt_lsof_kill_audio_processes())
-				return EACCES;
+			ret = igt_lsof_kill_audio_processes();
+			if (ret) {
+				igt_warn("Could not stop %d audio process(es)\n", ret);
+				igt_kmod_list_loaded();
+				igt_lsof("/dev/snd");
+				return 0;
+			}
 
 			kick_snd_hda_intel();
 			ret = igt_kmod_unload(*m, 0);
-			if (ret)
-				return ret;
+			if (ret) {
+				igt_warn("Could not unload audio driver %s\n", *m);
+				igt_kmod_list_loaded();
+				igt_lsof("/dev/snd");
+				return 0;
+			}
 		}
 	}
 	return 0;
@@ -610,6 +626,13 @@ int igt_audio_driver_unload(char **who)
 	}
 
 ret:
+	if (ret) {
+		igt_warn("Couldn't unload %s, which is using the %s driver\n",
+			 mod[pos].name, drm_driver);
+		igt_kmod_list_loaded();
+		igt_lsof("/dev/snd");
+	}
+
 	free_module_ref(mod, num_mod);
 
 	return ret;
diff --git a/tests/core_hotunplug.c b/tests/core_hotunplug.c
index 456ad6b4ce40..a0d29b799a48 100644
--- a/tests/core_hotunplug.c
+++ b/tests/core_hotunplug.c
@@ -149,11 +149,8 @@ static void driver_unbind(struct hotunplug *priv, const char *prefix,
 	 * unbind i915 driver, reloading it when binding again.
 	 */
 	if (igt_audio_driver_unload(&priv->snd_driver)) {
-		if (priv->snd_driver)
-			igt_warn("Could not unload audio driver %s\n", priv->snd_driver);
-		igt_kmod_list_loaded();
-		igt_lsof("/dev/snd");
-		igt_skip("Audio is in use, skipping\n");
+		igt_skip("Audio driver %s in use, skipping test\n",
+			 priv->snd_driver);
 	} else if (priv->snd_driver) {
 		igt_info("Unloaded audio driver %s\n", priv->snd_driver);
 	}
-- 
2.36.1