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drm/tests: Fix locking issues (kind of)

PATCH Applied Maxime Ripard 2 participants 10 messages Jan 29, 2025 – Feb 6, 2025

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Maxime Ripard

author maintainer
#0 lore raw

v2 cover drm/tests: Fix locking issues (kind of)

Hi,

Here's another attempt at fixing the current locking issues with the HDMI kunit tests.

The initial issue was reported by Dave here:
https://lore.kernel.org/all/CAPM=9tzJ4-ERDxvuwrCyUPY0=+P44orhp1kLWVGL7MCfpQjMEQ@mail.gmail.com/

After fixing it, there was still a lockdep warning for a circular dependency. This series is also fixing the issue.

There's still an issue though. When running the tests, I get:

KTAP version 1
1..1
KTAP version 1
# Subtest: drm_atomic_helper_connector_hdmi_check # module: drm_hdmi_state_helper_test
1..1

====================================
WARNING: kunit_try_catch/25 still has locks held!
6.13.0-rc2-00410-gbd9d16533367 #18 Tainted: G N
------------------------------------
2 locks held by kunit_try_catch/25:
#0: fff00000021586f0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_kunit_helper_acquire_ctx_alloc+0x5c/0xf0 #1: fff0000002158718 (crtc_ww_class_mutex){+.+.}-{0:0}, at: drm_kunit_helper_acquire_ctx_alloc+0x5c/0xf0

stack backtrace:
CPU: 0 UID: 0 PID: 25 Comm: kunit_try_catch Tainted: G                 N 6.13.0-rc2-00410-gbd9d16533367 #18
Tainted: [N]=TEST
Hardware name: linux,dummy-virt (DT)
Call trace:
 show_stack+0x18/0x30 (C)
 dump_stack_lvl+0x70/0x98
 dump_stack+0x18/0x24
 debug_check_no_locks_held+0x9c/0xa4
 do_exit+0x52c/0x970
 kthread_exit+0x28/0x30
 kthread+0xdc/0xf0
 ret_from_fork+0x10/0x20
    ok 1 drm_test_check_hdmi_funcs_reject_rate

ok 1 drm_atomic_helper_connector_hdmi_check

I believe it's due to the fact that drm_kunit_helper_acquire_ctx_alloc() will acquire the lock directly, but will release it as a deferred kunit action. It's not unsafe, as the lock is eventually released, but I don't really know what the best course of action is here:

* Forget about the idea of a context tied to the lifetime of a test
* Make lockdep know that it's ok, and we know what to do

I've tried the latter, using lockdep_pin/unpin_lock, but that didn't fix the issue so I must have done something wrong.

Let me know what you think,
Maxime

---
Changes in v2:
- Fix circular dependency warning
- Link to v1: https://lore.kernel.org/r/[email protected]

---
Maxime Ripard (4):
drm/tests: hdmi: Fix WW_MUTEX_SLOWPATH failures drm/tests: hdmi: Remove redundant assignments drm/tests: hdmi: Reorder DRM entities variables assignment drm/tests: hdmi: Fix recursive locking

 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 200 +++++++++++----------
 1 file changed, 103 insertions(+), 97 deletions(-)

---
base-commit: e2a81c0cd7de6cb063058be304b18f200c64802b
change-id: 20250129-test-kunit-5ba3c03bffb0

Best regards,

Signature · 1 line
Maxime Ripard <[email protected]>
author maintainer
#1 lore raw

PATCH v2 1/4 drm/tests: hdmi: Fix WW_MUTEX_SLOWPATH failures

The light_up_connector helper function in the HDMI infrastructure unit tests uses drm_atomic_set_crtc_for_connector(), but fails when it returns an error.

This function can return EDEADLK though if the sequence needs to be restarted, and WW_MUTEX_SLOWPATH is meant to test that we handle it properly.

Let's handle EDEADLK and restart the sequence in our tests as well.

---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 7 +++++++
 1 file changed, 7 insertions(+)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +7 -0
index c3b693bb966f1f8b04066d19f520bfa4bf11c23d..e814b538c46c4d342604436beca64ac0bdb31526 100644
@@ -68,14 +68,21 @@ static int light_up_connector(struct kunit *test,
 	int ret;
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
 
+retry:
 	conn_state = drm_atomic_get_connector_state(state, connector);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, conn_state);
 
 	ret = drm_atomic_set_crtc_for_connector(conn_state, crtc);
+	if (ret == -EDEADLK) {
+		drm_atomic_state_clear(state);
+		ret = drm_modeset_backoff(ctx);
+		if (!ret)
+			goto retry;
+	}
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	crtc_state = drm_atomic_get_crtc_state(state, crtc);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc_state);
 
Signature · 1 line
2.47.1
Reviewed-by on v2 1/4
#2 lore raw

Re: [PATCH v2 1/4] drm/tests: hdmi: Fix WW_MUTEX_SLOWPATH failures

Quoted 30 lines · Maxime Ripard

The light_up_connector helper function in the HDMI infrastructure unit tests uses drm_atomic_set_crtc_for_connector(), but fails when it returns an error.

This function can return EDEADLK though if the sequence needs to be restarted, and WW_MUTEX_SLOWPATH is meant to test that we handle it properly.

Let's handle EDEADLK and restart the sequence in our tests as well.

---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 7 +++++++
 1 file changed, 7 insertions(+)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +1 -0
index c3b693bb966f1f8b04066d19f520bfa4bf11c23d..e814b538c46c4d342604436beca64ac0bdb31526 100644
@@ -68,14 +68,21 @@ static int light_up_connector(struct kunit *test,
 	int ret;
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
 
+retry:

drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c static int light_up_connector(struct kunit *test, · line 83

Quoted 10 lines
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +6 -0
 	conn_state = drm_atomic_get_connector_state(state, connector);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, conn_state);
 
 	ret = drm_atomic_set_crtc_for_connector(conn_state, crtc);
+	if (ret == -EDEADLK) {
+		drm_atomic_state_clear(state);
+		ret = drm_modeset_backoff(ctx);
+		if (!ret)
+			goto retry;
+	}
Quoted 9 lines
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +0 -0
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	crtc_state = drm_atomic_get_crtc_state(state, crtc);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, crtc_state);
 
Signature · 2 lines
-- 
2.47.1
Signature · 3 lines
Simona Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
author maintainer
#3 lore raw

PATCH v2 2/4 drm/tests: hdmi: Remove redundant assignments

In reply to Maxime Ripard

Some tests have the drm pointer assigned multiple times to the same value. Drop the redundant assignments.

---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 4 ----
 1 file changed, 4 deletions(-)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +0 -4
index e814b538c46c4d342604436beca64ac0bdb31526..32e0477deb45c1481a7d23bb6e6a74de52845d1c 100644
@@ -479,11 +479,10 @@ static void drm_test_check_broadcast_rgb_auto_cea_mode_vic_1(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
@@ -593,11 +592,10 @@ static void drm_test_check_broadcast_rgb_full_cea_mode_vic_1(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
@@ -709,11 +707,10 @@ static void drm_test_check_broadcast_rgb_limited_cea_mode_vic_1(struct kunit *te
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
@@ -1311,11 +1308,10 @@ static void drm_test_check_output_bpc_format_vic_1(struct kunit *test)
 	 * Thus, we have to calculate the rate by hand.
 	 */
 	rate = mode->clock * 1500;
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
Signature · 1 line
2.47.1
Reviewed-by on v2 2/4
#4 lore raw

Re: [PATCH v2 2/4] drm/tests: hdmi: Remove redundant assignments

Quoted 4 lines · Maxime Ripard

Some tests have the drm pointer assigned multiple times to the same value. Drop the redundant assignments.

Quoted 60 lines
---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 4 ----
 1 file changed, 4 deletions(-)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +0 -4
index e814b538c46c4d342604436beca64ac0bdb31526..32e0477deb45c1481a7d23bb6e6a74de52845d1c 100644
@@ -479,11 +479,10 @@ static void drm_test_check_broadcast_rgb_auto_cea_mode_vic_1(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
@@ -593,11 +592,10 @@ static void drm_test_check_broadcast_rgb_full_cea_mode_vic_1(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
@@ -709,11 +707,10 @@ static void drm_test_check_broadcast_rgb_limited_cea_mode_vic_1(struct kunit *te
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
@@ -1311,11 +1308,10 @@ static void drm_test_check_output_bpc_format_vic_1(struct kunit *test)
 	 * Thus, we have to calculate the rate by hand.
 	 */
 	rate = mode->clock * 1500;
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
Signature · 2 lines
-- 
2.47.1
Signature · 3 lines
Simona Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
author maintainer
#5 lore raw

PATCH v2 3/4 drm/tests: hdmi: Reorder DRM entities variables assignment

In reply to Maxime Ripard

The tests all deviate slightly in how they assign their local pointers to DRM entities. This makes refactoring pretty difficult, so let's just move the assignment as soon as the entities are allocated.

---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 81 +++++++++++-----------
 1 file changed, 42 insertions(+), 39 deletions(-)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +42 -39
index 32e0477deb45c1481a7d23bb6e6a74de52845d1c..c265d28631603f266ba606564e77b8f965b7f83b 100644
@@ -287,19 +287,20 @@ static void drm_test_check_broadcast_rgb_crtc_mode_changed(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
+	conn = &priv->connector;
+
 	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
-	conn = &priv->connector;
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -350,19 +351,20 @@ static void drm_test_check_broadcast_rgb_crtc_mode_not_changed(struct kunit *tes
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
+	conn = &priv->connector;
+
 	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
-	conn = &priv->connector;
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -413,22 +415,22 @@ static void drm_test_check_broadcast_rgb_auto_cea_mode(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
 	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -524,22 +526,22 @@ static void drm_test_check_broadcast_rgb_full_cea_mode(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
 	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -639,22 +641,22 @@ static void drm_test_check_broadcast_rgb_limited_cea_mode(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
 	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -756,10 +758,12 @@ static void drm_test_check_output_bpc_crtc_mode_changed(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    10);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -768,12 +772,10 @@ static void drm_test_check_output_bpc_crtc_mode_changed(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -830,10 +832,12 @@ static void drm_test_check_output_bpc_crtc_mode_not_changed(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    10);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -842,12 +846,10 @@ static void drm_test_check_output_bpc_crtc_mode_not_changed(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -901,10 +903,12 @@ static void drm_test_check_output_bpc_dvi(struct kunit *test)
 						    BIT(HDMI_COLORSPACE_YUV422) |
 						    BIT(HDMI_COLORSPACE_YUV444),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_dvi_1080p,
 				 ARRAY_SIZE(test_edid_dvi_1080p));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -916,12 +920,10 @@ static void drm_test_check_output_bpc_dvi(struct kunit *test)
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -948,10 +950,12 @@ static void drm_test_check_tmds_char_rate_rgb_8bpc(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -961,12 +965,10 @@ static void drm_test_check_tmds_char_rate_rgb_8bpc(struct kunit *test)
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -995,10 +997,12 @@ static void drm_test_check_tmds_char_rate_rgb_10bpc(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    10);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1008,12 +1012,10 @@ static void drm_test_check_tmds_char_rate_rgb_10bpc(struct kunit *test)
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1042,10 +1044,12 @@ static void drm_test_check_tmds_char_rate_rgb_12bpc(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1055,12 +1059,10 @@ static void drm_test_check_tmds_char_rate_rgb_12bpc(struct kunit *test)
 
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1093,19 +1095,20 @@ static void drm_test_check_hdmi_funcs_reject_rate(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
+	conn = &priv->connector;
+
 	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
 
-	conn = &priv->connector;
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	/* You shouldn't be doing that at home. */
 	conn->hdmi.funcs = &reject_connector_hdmi_funcs;
@@ -1149,10 +1152,12 @@ static void drm_test_check_max_tmds_rate_bpc_fallback(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1172,12 +1177,10 @@ static void drm_test_check_max_tmds_rate_bpc_fallback(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 10, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1218,10 +1221,12 @@ static void drm_test_check_max_tmds_rate_format_fallback(struct kunit *test)
 						    BIT(HDMI_COLORSPACE_YUV422) |
 						    BIT(HDMI_COLORSPACE_YUV444),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1244,12 +1249,10 @@ static void drm_test_check_max_tmds_rate_format_fallback(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1341,10 +1344,12 @@ static void drm_test_check_output_bpc_format_driver_rgb_only(struct kunit *test)
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1372,12 +1377,10 @@ static void drm_test_check_output_bpc_format_driver_rgb_only(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1408,10 +1411,12 @@ static void drm_test_check_output_bpc_format_display_rgb_only(struct kunit *test
 						    BIT(HDMI_COLORSPACE_YUV422) |
 						    BIT(HDMI_COLORSPACE_YUV444),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1439,12 +1444,10 @@ static void drm_test_check_output_bpc_format_display_rgb_only(struct kunit *test
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1474,10 +1477,12 @@ static void drm_test_check_output_bpc_format_driver_8bpc_only(struct kunit *test
 	priv = drm_kunit_helper_connector_hdmi_init(test,
 						    BIT(HDMI_COLORSPACE_RGB),
 						    8);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1497,12 +1502,10 @@ static void drm_test_check_output_bpc_format_driver_8bpc_only(struct kunit *test
 	 * clock to actually use 12bpc.
 	 */
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1534,10 +1537,12 @@ static void drm_test_check_output_bpc_format_display_8bpc_only(struct kunit *tes
 						    BIT(HDMI_COLORSPACE_YUV422) |
 						    BIT(HDMI_COLORSPACE_YUV444),
 						    12);
 	KUNIT_ASSERT_NOT_NULL(test, priv);
 
+	drm = &priv->drm;
+	crtc = priv->crtc;
 	conn = &priv->connector;
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
@@ -1557,12 +1562,10 @@ static void drm_test_check_output_bpc_format_display_8bpc_only(struct kunit *tes
 	 * clock to actually use 12bpc.
 	 */
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
-	drm = &priv->drm;
-	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
Signature · 1 line
2.47.1
author maintainer
#6 lore raw

PATCH v2 4/4 drm/tests: hdmi: Fix recursive locking

In reply to Maxime Ripard

The find_preferred_mode() functions takes the mode_config mutex, but due to the order most tests have, is called with the crtc_ww_class_mutex taken. This raises a warning for a circular dependency when running the tests with lockdep.

Reorder the tests to call find_preferred_mode before the acquire context has been created to avoid the issue.

---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 114 ++++++++++-----------
 1 file changed, 57 insertions(+), 57 deletions(-)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +57 -57
index c265d28631603f266ba606564e77b8f965b7f83b..037c19875daf8b9b13e7702c8640dde1547f817c 100644
@@ -291,16 +291,16 @@ static void drm_test_check_broadcast_rgb_crtc_mode_changed(struct kunit *test)
 
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -355,16 +355,16 @@ static void drm_test_check_broadcast_rgb_crtc_mode_not_changed(struct kunit *tes
 
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -420,17 +420,17 @@ static void drm_test_check_broadcast_rgb_auto_cea_mode(struct kunit *test)
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -531,17 +531,17 @@ static void drm_test_check_broadcast_rgb_full_cea_mode(struct kunit *test)
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -646,17 +646,17 @@ static void drm_test_check_broadcast_rgb_limited_cea_mode(struct kunit *test)
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -766,16 +766,16 @@ static void drm_test_check_output_bpc_crtc_mode_changed(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -840,16 +840,16 @@ static void drm_test_check_output_bpc_crtc_mode_not_changed(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -914,16 +914,16 @@ static void drm_test_check_output_bpc_dvi(struct kunit *test)
 	KUNIT_ASSERT_GT(test, ret, 0);
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_FALSE(test, info->is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -958,17 +958,17 @@ static void drm_test_check_tmds_char_rate_rgb_8bpc(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1005,17 +1005,17 @@ static void drm_test_check_tmds_char_rate_rgb_10bpc(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1052,17 +1052,17 @@ static void drm_test_check_tmds_char_rate_rgb_12bpc(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1099,16 +1099,16 @@ static void drm_test_check_hdmi_funcs_reject_rate(struct kunit *test)
 
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	/* You shouldn't be doing that at home. */
 	conn->hdmi.funcs = &reject_connector_hdmi_funcs;
@@ -1164,23 +1164,23 @@ static void drm_test_check_max_tmds_rate_bpc_fallback(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 10, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1233,13 +1233,10 @@ static void drm_test_check_max_tmds_rate_format_fallback(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 10, HDMI_COLORSPACE_RGB);
@@ -1249,10 +1246,13 @@ static void drm_test_check_max_tmds_rate_format_fallback(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1295,13 +1295,10 @@ static void drm_test_check_output_bpc_format_vic_1(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	/*
 	 * NOTE: We can't use drm_hdmi_compute_mode_clock()
@@ -1311,10 +1308,13 @@ static void drm_test_check_output_bpc_format_vic_1(struct kunit *test)
 	 * Thus, we have to calculate the rate by hand.
 	 */
 	rate = mode->clock * 1500;
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
@@ -1356,13 +1356,10 @@ static void drm_test_check_output_bpc_format_driver_rgb_only(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that YUV422 would be the preferred option
@@ -1377,10 +1374,13 @@ static void drm_test_check_output_bpc_format_driver_rgb_only(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1423,13 +1423,10 @@ static void drm_test_check_output_bpc_format_display_rgb_only(struct kunit *test
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that YUV422 would be the preferred option
@@ -1444,10 +1441,13 @@ static void drm_test_check_output_bpc_format_display_rgb_only(struct kunit *test
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1489,23 +1489,23 @@ static void drm_test_check_output_bpc_format_driver_8bpc_only(struct kunit *test
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that we have headroom on the TMDS character
 	 * clock to actually use 12bpc.
 	 */
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1549,23 +1549,23 @@ static void drm_test_check_output_bpc_format_display_8bpc_only(struct kunit *tes
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that we have headroom on the TMDS character
 	 * clock to actually use 12bpc.
 	 */
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
Signature · 1 line
2.47.1
#7 lore raw

Re: [PATCH v2 4/4] drm/tests: hdmi: Fix recursive locking

Quoted 9 lines · Maxime Ripard

The find_preferred_mode() functions takes the mode_config mutex, but due to the order most tests have, is called with the crtc_ww_class_mutex taken. This raises a warning for a circular dependency when running the tests with lockdep.

Reorder the tests to call find_preferred_mode before the acquire context has been created to avoid the issue.

On the last two patches: Reviewed-by: Simona Vetter <[email protected]>

Quoted 451 lines
---
 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 114 ++++++++++-----------
 1 file changed, 57 insertions(+), 57 deletions(-)
drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c +57 -57
index c265d28631603f266ba606564e77b8f965b7f83b..037c19875daf8b9b13e7702c8640dde1547f817c 100644
@@ -291,16 +291,16 @@ static void drm_test_check_broadcast_rgb_crtc_mode_changed(struct kunit *test)
 
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -355,16 +355,16 @@ static void drm_test_check_broadcast_rgb_crtc_mode_not_changed(struct kunit *tes
 
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -420,17 +420,17 @@ static void drm_test_check_broadcast_rgb_auto_cea_mode(struct kunit *test)
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -531,17 +531,17 @@ static void drm_test_check_broadcast_rgb_full_cea_mode(struct kunit *test)
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -646,17 +646,17 @@ static void drm_test_check_broadcast_rgb_limited_cea_mode(struct kunit *test)
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 	KUNIT_ASSERT_TRUE(test, conn->display_info.is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_NE(test, drm_match_cea_mode(preferred), 1);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -766,16 +766,16 @@ static void drm_test_check_output_bpc_crtc_mode_changed(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -840,16 +840,16 @@ static void drm_test_check_output_bpc_crtc_mode_not_changed(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	state = drm_kunit_helper_atomic_state_alloc(test, drm, ctx);
 	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, state);
@@ -914,16 +914,16 @@ static void drm_test_check_output_bpc_dvi(struct kunit *test)
 	KUNIT_ASSERT_GT(test, ret, 0);
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_FALSE(test, info->is_hdmi);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -958,17 +958,17 @@ static void drm_test_check_tmds_char_rate_rgb_8bpc(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_max_200mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_max_200mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1005,17 +1005,17 @@ static void drm_test_check_tmds_char_rate_rgb_10bpc(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1052,17 +1052,17 @@ static void drm_test_check_tmds_char_rate_rgb_12bpc(struct kunit *test)
 	ret = set_connector_edid(test, conn,
 				 test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz,
 				 ARRAY_SIZE(test_edid_hdmi_1080p_rgb_yuv_dc_max_340mhz));
 	KUNIT_ASSERT_GT(test, ret, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1099,16 +1099,16 @@ static void drm_test_check_hdmi_funcs_reject_rate(struct kunit *test)
 
 	drm = &priv->drm;
 	crtc = priv->crtc;
 	conn = &priv->connector;
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_ASSERT_EQ(test, ret, 0);
 
 	/* You shouldn't be doing that at home. */
 	conn->hdmi.funcs = &reject_connector_hdmi_funcs;
@@ -1164,23 +1164,23 @@ static void drm_test_check_max_tmds_rate_bpc_fallback(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 10, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1233,13 +1233,10 @@ static void drm_test_check_max_tmds_rate_format_fallback(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 	KUNIT_ASSERT_FALSE(test, preferred->flags & DRM_MODE_FLAG_DBLCLK);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 10, HDMI_COLORSPACE_RGB);
@@ -1249,10 +1246,13 @@ static void drm_test_check_max_tmds_rate_format_fallback(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1295,13 +1295,10 @@ static void drm_test_check_output_bpc_format_vic_1(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	/*
 	 * NOTE: We can't use drm_hdmi_compute_mode_clock()
@@ -1311,10 +1308,13 @@ static void drm_test_check_output_bpc_format_vic_1(struct kunit *test)
 	 * Thus, we have to calculate the rate by hand.
 	 */
 	rate = mode->clock * 1500;
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	crtc = priv->crtc;
 	ret = light_up_connector(test, drm, crtc, conn, mode, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
@@ -1356,13 +1356,10 @@ static void drm_test_check_output_bpc_format_driver_rgb_only(struct kunit *test)
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that YUV422 would be the preferred option
@@ -1377,10 +1374,13 @@ static void drm_test_check_output_bpc_format_driver_rgb_only(struct kunit *test)
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1423,13 +1423,10 @@ static void drm_test_check_output_bpc_format_display_rgb_only(struct kunit *test
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that YUV422 would be the preferred option
@@ -1444,10 +1441,13 @@ static void drm_test_check_output_bpc_format_display_rgb_only(struct kunit *test
 	KUNIT_ASSERT_GT(test, rate, info->max_tmds_clock * 1000);
 
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_YUV422);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1489,23 +1489,23 @@ static void drm_test_check_output_bpc_format_driver_8bpc_only(struct kunit *test
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that we have headroom on the TMDS character
 	 * clock to actually use 12bpc.
 	 */
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
@@ -1549,23 +1549,23 @@ static void drm_test_check_output_bpc_format_display_8bpc_only(struct kunit *tes
 
 	info = &conn->display_info;
 	KUNIT_ASSERT_TRUE(test, info->is_hdmi);
 	KUNIT_ASSERT_GT(test, info->max_tmds_clock, 0);
 
-	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
-
 	preferred = find_preferred_mode(conn);
 	KUNIT_ASSERT_NOT_NULL(test, preferred);
 
 	/*
 	 * We're making sure that we have headroom on the TMDS character
 	 * clock to actually use 12bpc.
 	 */
 	rate = drm_hdmi_compute_mode_clock(preferred, 12, HDMI_COLORSPACE_RGB);
 	KUNIT_ASSERT_LT(test, rate, info->max_tmds_clock * 1000);
 
+	ctx = drm_kunit_helper_acquire_ctx_alloc(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, ctx);
+
 	ret = light_up_connector(test, drm, crtc, conn, preferred, ctx);
 	KUNIT_EXPECT_EQ(test, ret, 0);
 
 	conn_state = conn->state;
 	KUNIT_ASSERT_NOT_NULL(test, conn_state);
Signature · 2 lines
-- 
2.47.1
Signature · 3 lines
Simona Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
#8 lore raw
In reply to Maxime Ripard
Quoted 10 lines · Maxime Ripard

Hi,

Here's another attempt at fixing the current locking issues with the HDMI kunit tests.

The initial issue was reported by Dave here:
https://lore.kernel.org/all/CAPM=9tzJ4-ERDxvuwrCyUPY0=+P44orhp1kLWVGL7MCfpQjMEQ@mail.gmail.com/

After fixing it, there was still a lockdep warning for a circular dependency. This series is also fixing the issue.

So this looks like it's a kthread_exit, which yes is broken. You cannot acquire a lock in one thread and release it in another thread, that does not work for lockdep and therefore is forbidden for mutexes.

It's kinda allowed for semaphore, but that's why semaphores cannot be automatically checked by lockdep. So yeah we cannot use such a deferred action, it would need to be a deferred action that's run synchronously. -Sima

Quoted 71 lines

There's still an issue though. When running the tests, I get:

KTAP version 1
1..1
KTAP version 1
# Subtest: drm_atomic_helper_connector_hdmi_check # module: drm_hdmi_state_helper_test
1..1

====================================
WARNING: kunit_try_catch/25 still has locks held!
6.13.0-rc2-00410-gbd9d16533367 #18 Tainted: G N
------------------------------------
2 locks held by kunit_try_catch/25:
#0: fff00000021586f0 (crtc_ww_class_acquire){+.+.}-{0:0}, at: drm_kunit_helper_acquire_ctx_alloc+0x5c/0xf0 #1: fff0000002158718 (crtc_ww_class_mutex){+.+.}-{0:0}, at: drm_kunit_helper_acquire_ctx_alloc+0x5c/0xf0

stack backtrace:
CPU: 0 UID: 0 PID: 25 Comm: kunit_try_catch Tainted: G                 N 6.13.0-rc2-00410-gbd9d16533367 #18
Tainted: [N]=TEST
Hardware name: linux,dummy-virt (DT)
Call trace:
 show_stack+0x18/0x30 (C)
 dump_stack_lvl+0x70/0x98
 dump_stack+0x18/0x24
 debug_check_no_locks_held+0x9c/0xa4
 do_exit+0x52c/0x970
 kthread_exit+0x28/0x30
 kthread+0xdc/0xf0
 ret_from_fork+0x10/0x20
    ok 1 drm_test_check_hdmi_funcs_reject_rate

ok 1 drm_atomic_helper_connector_hdmi_check

I believe it's due to the fact that drm_kunit_helper_acquire_ctx_alloc() will acquire the lock directly, but will release it as a deferred kunit action. It's not unsafe, as the lock is eventually released, but I don't really know what the best course of action is here:

* Forget about the idea of a context tied to the lifetime of a test
* Make lockdep know that it's ok, and we know what to do

I've tried the latter, using lockdep_pin/unpin_lock, but that didn't fix the issue so I must have done something wrong.

Let me know what you think,
Maxime

---
Changes in v2:
- Fix circular dependency warning
- Link to v1: https://lore.kernel.org/r/[email protected]

---
Maxime Ripard (4):
drm/tests: hdmi: Fix WW_MUTEX_SLOWPATH failures drm/tests: hdmi: Remove redundant assignments drm/tests: hdmi: Reorder DRM entities variables assignment drm/tests: hdmi: Fix recursive locking

 drivers/gpu/drm/tests/drm_hdmi_state_helper_test.c | 200 +++++++++++----------
 1 file changed, 103 insertions(+), 97 deletions(-)

---
base-commit: e2a81c0cd7de6cb063058be304b18f200c64802b
change-id: 20250129-test-kunit-5ba3c03bffb0

Best regards,

Signature · 1 line
Maxime Ripard <[email protected]>
Signature · 3 lines
Simona Vetter
Software Engineer, Intel Corporation
http://blog.ffwll.ch
author maintainer Applied
#9 lore raw
In reply to Maxime Ripard
Quoted 10 lines · Maxime Ripard

Here's another attempt at fixing the current locking issues with the HDMI kunit tests.

The initial issue was reported by Dave here:
https://lore.kernel.org/all/CAPM=9tzJ4-ERDxvuwrCyUPY0=+P44orhp1kLWVGL7MCfpQjMEQ@mail.gmail.com/

After fixing it, there was still a lockdep warning for a circular dependency. This series is also fixing the issue.

[...]

Applied to misc/kernel.git (drm-misc-fixes).

Thanks!
Maxime