modprobe drm_connector_test and then rmmod drm_connector_test,
the following memory leak occurs.

The `mode` allocated in drm_mode_duplicate() called by
drm_display_mode_from_cea_vic() is not freed, which cause the memory leak:

	unreferenced object 0xffffff80cb0ee400 (size 128):
	  comm "kunit_try_catch", pid 1948, jiffies 4294950339
	  hex dump (first 32 bytes):
	    14 44 02 00 80 07 d8 07 04 08 98 08 00 00 38 04  .D............8.
	    3c 04 41 04 65 04 00 00 05 00 00 00 00 00 00 00  <.A.e...........
	  backtrace (crc 90e9585c):
	    [<00000000ec42e3d7>] kmemleak_alloc+0x34/0x40
	    [<00000000d0ef055a>] __kmalloc_cache_noprof+0x26c/0x2f4
	    [<00000000c2062161>] drm_mode_duplicate+0x44/0x19c
	    [<00000000f96c74aa>] drm_display_mode_from_cea_vic+0x88/0x98
	    [<00000000d8f2c8b4>] 0xffffffdc982a4868
	    [<000000005d164dbc>] kunit_try_run_case+0x13c/0x3ac
	    [<000000006fb23398>] kunit_generic_run_threadfn_adapter+0x80/0xec
	    [<000000006ea56ca0>] kthread+0x2e8/0x374
	    [<000000000676063f>] ret_from_fork+0x10/0x20
	......

Free `mode` by using drm_kunit_display_mode_from_cea_vic()
to fix it.

Cc: stable@vger.kernel.org
Fixes: abb6f74973e2 ("drm/tests: Add HDMI TDMS character rate tests")
Acked-by: Maxime Ripard <mripard@kernel.org>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
---
v3:
- Update the commit message.
- Add Acked-by.
v2:
- Fix it with new introduced helper instead of drm_mode_destroy().
- Update the commit message.
---
 drivers/gpu/drm/tests/drm_connector_test.c | 24 +++++++++++-----------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/gpu/drm/tests/drm_connector_test.c b/drivers/gpu/drm/tests/drm_connector_test.c
index 15e36a8db685..6bba97d0be88 100644
--- a/drivers/gpu/drm/tests/drm_connector_test.c
+++ b/drivers/gpu/drm/tests/drm_connector_test.c
@@ -996,7 +996,7 @@ static void drm_test_drm_hdmi_compute_mode_clock_rgb(struct kunit *test)
 	unsigned long long rate;
 	struct drm_device *drm = &priv->drm;
 
-	mode = drm_display_mode_from_cea_vic(drm, 16);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 16);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1017,7 +1017,7 @@ static void drm_test_drm_hdmi_compute_mode_clock_rgb_10bpc(struct kunit *test)
 	unsigned long long rate;
 	struct drm_device *drm = &priv->drm;
 
-	mode = drm_display_mode_from_cea_vic(drm, 16);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 16);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1038,7 +1038,7 @@ static void drm_test_drm_hdmi_compute_mode_clock_rgb_10bpc_vic_1(struct kunit *t
 	unsigned long long rate;
 	struct drm_device *drm = &priv->drm;
 
-	mode = drm_display_mode_from_cea_vic(drm, 1);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	rate = drm_hdmi_compute_mode_clock(mode, 10, HDMI_COLORSPACE_RGB);
@@ -1056,7 +1056,7 @@ static void drm_test_drm_hdmi_compute_mode_clock_rgb_12bpc(struct kunit *test)
 	unsigned long long rate;
 	struct drm_device *drm = &priv->drm;
 
-	mode = drm_display_mode_from_cea_vic(drm, 16);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 16);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1077,7 +1077,7 @@ static void drm_test_drm_hdmi_compute_mode_clock_rgb_12bpc_vic_1(struct kunit *t
 	unsigned long long rate;
 	struct drm_device *drm = &priv->drm;
 
-	mode = drm_display_mode_from_cea_vic(drm, 1);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 1);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	rate = drm_hdmi_compute_mode_clock(mode, 12, HDMI_COLORSPACE_RGB);
@@ -1095,7 +1095,7 @@ static void drm_test_drm_hdmi_compute_mode_clock_rgb_double(struct kunit *test)
 	unsigned long long rate;
 	struct drm_device *drm = &priv->drm;
 
-	mode = drm_display_mode_from_cea_vic(drm, 6);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 6);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_TRUE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1118,7 +1118,7 @@ static void drm_test_connector_hdmi_compute_mode_clock_yuv420_valid(struct kunit
 	unsigned long long rate;
 	unsigned int vic = *(unsigned int *)test->param_value;
 
-	mode = drm_display_mode_from_cea_vic(drm, vic);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, vic);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1155,7 +1155,7 @@ static void drm_test_connector_hdmi_compute_mode_clock_yuv420_10_bpc(struct kuni
 		drm_hdmi_compute_mode_clock_yuv420_vic_valid_tests[0];
 	unsigned long long rate;
 
-	mode = drm_display_mode_from_cea_vic(drm, vic);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, vic);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1180,7 +1180,7 @@ static void drm_test_connector_hdmi_compute_mode_clock_yuv420_12_bpc(struct kuni
 		drm_hdmi_compute_mode_clock_yuv420_vic_valid_tests[0];
 	unsigned long long rate;
 
-	mode = drm_display_mode_from_cea_vic(drm, vic);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, vic);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1203,7 +1203,7 @@ static void drm_test_connector_hdmi_compute_mode_clock_yuv422_8_bpc(struct kunit
 	struct drm_device *drm = &priv->drm;
 	unsigned long long rate;
 
-	mode = drm_display_mode_from_cea_vic(drm, 16);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 16);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1225,7 +1225,7 @@ static void drm_test_connector_hdmi_compute_mode_clock_yuv422_10_bpc(struct kuni
 	struct drm_device *drm = &priv->drm;
 	unsigned long long rate;
 
-	mode = drm_display_mode_from_cea_vic(drm, 16);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 16);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
@@ -1247,7 +1247,7 @@ static void drm_test_connector_hdmi_compute_mode_clock_yuv422_12_bpc(struct kuni
 	struct drm_device *drm = &priv->drm;
 	unsigned long long rate;
 
-	mode = drm_display_mode_from_cea_vic(drm, 16);
+	mode = drm_kunit_display_mode_from_cea_vic(test, drm, 16);
 	KUNIT_ASSERT_NOT_NULL(test, mode);
 
 	KUNIT_ASSERT_FALSE(test, mode->flags & DRM_MODE_FLAG_DBLCLK);
-- 
2.34.1