[PATCH v4 RESEND 0/9] Increase coverage on drm_framebuffer.c

[PATCH v4 RESEND 0/9] Increase coverage on drm_framebuffer.c

[Carlos Eduardo Gallo Filho]

This patchset includes new KUnit tests for 5 untested functions from
drm_framebuffer.c and improvements to the existent one.

The first patch replace the use of dev_private member from drm_device
mock on the existent test by embedding it into an outer struct containing
a generic pointer.

The patches 2 and 4 extends the test of drm_internal_framebuffer_create()
by creating a new test case and adding new parameters to the existent case.

The patch 3 just replace a strcpy() call to strscpy().

Finally, the remainder of this set contains 5 new test cases, one for each
of the follow functions:

- drm_framebuffer_check_src_coords()
- drm_framebuffer_cleanup()
- drm_framebuffer_lookup()
- drm_framebuffer_init()
- drm_framebuffer_free()

---
v3:
  - Drop drm_mode_addfb2 and drm_fb_release tests (patches 10 and 11 from v2)
---

Carlos Eduardo Gallo Filho (9):
  drm/tests: Stop using deprecated dev_private member on drm_framebuffer
    tests
  drm/tests: Add parameters to the drm_test_framebuffer_create test
  drm/tests: Replace strcpy to strscpy on drm_test_framebuffer_create
    test
  drm/tests: Add test case for drm_internal_framebuffer_create()
  drm/tests: Add test for drm_framebuffer_check_src_coords()
  drm/tests: Add test for drm_framebuffer_cleanup()
  drm/tests: Add test for drm_framebuffer_lookup()
  drm/tests: Add test for drm_framebuffer_init()
  drm/tests: Add test for drm_framebuffer_free()

 drivers/gpu/drm/drm_framebuffer.c            |   2 +
 drivers/gpu/drm/drm_mode_object.c            |   1 +
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 375 ++++++++++++++++++-
 3 files changed, 361 insertions(+), 17 deletions(-)

-- 
2.44.2

[PATCH v4 RESEND 1/9] drm/tests: Stop using deprecated dev_private member on drm_framebuffer tests

[Carlos Eduardo Gallo Filho]

The dev_private member of drm_device is deprecated and its use should
be avoided. Stop using it by embedding the drm_device onto a mock struct.

The new mock struct allows to share variables and even further mocks
over the tests in a cleaner way than using dev_private void pointer.

Also start using drm_kunit_helper_alloc_drm_device() for allocating
the drm_device mock.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
v2:
  - Start using drm_kunit_helper_alloc_drm_device() for drm_device mock.
  - Rename struct drm_mock to drm_framebuffer_test_priv
v3:
  - Replace the use of void pointer on drm_framebuffer_test_priv struct.
  - Document struct drm_framebuffer_test_priv here.
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 54 ++++++++++++++------
 1 file changed, 38 insertions(+), 16 deletions(-)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 06f03b78c9c4..3882a88b6631 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -8,8 +8,10 @@
 #include <kunit/test.h>
 
 #include <drm/drm_device.h>
+#include <drm/drm_drv.h>
 #include <drm/drm_mode.h>
 #include <drm/drm_fourcc.h>
+#include <drm/drm_kunit_helpers.h>
 #include <drm/drm_print.h>
 
 #include "../drm_crtc_internal.h"
@@ -317,12 +319,25 @@ static const struct drm_framebuffer_test drm_framebuffer_create_cases[] = {
 },
 };
 
+/*
+ * This struct is intended to provide a way to mocked functions communicate
+ * with the outer test when it can't be achieved by using its return value. In
+ * this way, the functions that receive the mocked drm_device, for example, can
+ * grab a reference to this and actually return something to be used on some
+ * expectation.
+ */
+struct drm_framebuffer_test_priv {
+	struct drm_device dev;
+	bool buffer_created;
+};
+
 static struct drm_framebuffer *fb_create_mock(struct drm_device *dev,
 					      struct drm_file *file_priv,
 					      const struct drm_mode_fb_cmd2 *mode_cmd)
 {
-	int *buffer_created = dev->dev_private;
-	*buffer_created = 1;
+	struct drm_framebuffer_test_priv *priv = container_of(dev, typeof(*priv), dev);
+
+	priv->buffer_created = true;
 	return ERR_PTR(-EINVAL);
 }
 
@@ -332,30 +347,37 @@ static struct drm_mode_config_funcs mock_config_funcs = {
 
 static int drm_framebuffer_test_init(struct kunit *test)
 {
-	struct drm_device *mock;
+	struct device *parent;
+	struct drm_framebuffer_test_priv *priv;
+	struct drm_device *dev;
+
+	parent = drm_kunit_helper_alloc_device(test);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, parent);
 
-	mock = kunit_kzalloc(test, sizeof(*mock), GFP_KERNEL);
-	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, mock);
+	priv = drm_kunit_helper_alloc_drm_device(test, parent, typeof(*priv),
+						 dev, 0);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, priv);
+	dev = &priv->dev;
 
-	mock->mode_config.min_width = MIN_WIDTH;
-	mock->mode_config.max_width = MAX_WIDTH;
-	mock->mode_config.min_height = MIN_HEIGHT;
-	mock->mode_config.max_height = MAX_HEIGHT;
-	mock->mode_config.funcs = &mock_config_funcs;
+	dev->mode_config.min_width = MIN_WIDTH;
+	dev->mode_config.max_width = MAX_WIDTH;
+	dev->mode_config.min_height = MIN_HEIGHT;
+	dev->mode_config.max_height = MAX_HEIGHT;
+	dev->mode_config.funcs = &mock_config_funcs;
 
-	test->priv = mock;
+	test->priv = priv;
 	return 0;
 }
 
 static void drm_test_framebuffer_create(struct kunit *test)
 {
 	const struct drm_framebuffer_test *params = test->param_value;
-	struct drm_device *mock = test->priv;
-	int buffer_created = 0;
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
 
-	mock->dev_private = &buffer_created;
-	drm_internal_framebuffer_create(mock, &params->cmd, NULL);
-	KUNIT_EXPECT_EQ(test, params->buffer_created, buffer_created);
+	priv->buffer_created = false;
+	drm_internal_framebuffer_create(dev, &params->cmd, NULL);
+	KUNIT_EXPECT_EQ(test, params->buffer_created, priv->buffer_created);
 }
 
 static void drm_framebuffer_test_to_desc(const struct drm_framebuffer_test *t, char *desc)
-- 
2.44.2

[PATCH v4 RESEND 2/9] drm/tests: Add parameters to the drm_test_framebuffer_create test

[Carlos Eduardo Gallo Filho]

Extend the existing test case to cover:
1. Invalid flag atribute in the struct drm_mode_fb_cmd2.
2. Pixel format which requires non-linear modifier with
DRM_FORMAT_MOD_LINEAR set.
3. Buffer offset for inexistent plane

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
v2:
  - Remove strcpy to strscpy change.
v3:
  - Rename and commment the "Buffer offset for inexistent plane"
    test case.
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 27 ++++++++++++++++++++
 1 file changed, 27 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 3882a88b6631..3ed987423322 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -21,6 +21,8 @@
 #define MIN_HEIGHT 4
 #define MAX_HEIGHT 4096
 
+#define DRM_MODE_FB_INVALID BIT(2)
+
 struct drm_framebuffer_test {
 	int buffer_created;
 	struct drm_mode_fb_cmd2 cmd;
@@ -85,6 +87,24 @@ static const struct drm_framebuffer_test drm_framebuffer_create_cases[] = {
 		 .pitches = { 4 * MAX_WIDTH, 0, 0 },
 	}
 },
+
+/*
+ * All entries in members that represents per-plane values (@modifier, @handles,
+ * @pitches and @offsets) must be zero when unused.
+ */
+{ .buffer_created = 0, .name = "ABGR8888 Buffer offset for inexistent plane",
+	.cmd = { .width = MAX_WIDTH, .height = MAX_HEIGHT, .pixel_format = DRM_FORMAT_ABGR8888,
+		 .handles = { 1, 0, 0 }, .offsets = { UINT_MAX / 2, UINT_MAX / 2, 0 },
+		 .pitches = { 4 * MAX_WIDTH, 0, 0 }, .flags = DRM_MODE_FB_MODIFIERS,
+	}
+},
+
+{ .buffer_created = 0, .name = "ABGR8888 Invalid flag",
+	.cmd = { .width = MAX_WIDTH, .height = MAX_HEIGHT, .pixel_format = DRM_FORMAT_ABGR8888,
+		 .handles = { 1, 0, 0 }, .offsets = { UINT_MAX / 2, 0, 0 },
+		 .pitches = { 4 * MAX_WIDTH, 0, 0 }, .flags = DRM_MODE_FB_INVALID,
+	}
+},
 { .buffer_created = 1, .name = "ABGR8888 Set DRM_MODE_FB_MODIFIERS without modifiers",
 	.cmd = { .width = MAX_WIDTH, .height = MAX_HEIGHT, .pixel_format = DRM_FORMAT_ABGR8888,
 		 .handles = { 1, 0, 0 }, .offsets = { UINT_MAX / 2, 0, 0 },
@@ -264,6 +284,13 @@ static const struct drm_framebuffer_test drm_framebuffer_create_cases[] = {
 		 .pitches = { MAX_WIDTH, DIV_ROUND_UP(MAX_WIDTH, 2), DIV_ROUND_UP(MAX_WIDTH, 2) },
 	}
 },
+{ .buffer_created = 0, .name = "YUV420_10BIT Invalid modifier(DRM_FORMAT_MOD_LINEAR)",
+	.cmd = { .width = MAX_WIDTH, .height = MAX_HEIGHT, .pixel_format = DRM_FORMAT_YUV420_10BIT,
+		 .handles = { 1, 0, 0 }, .flags = DRM_MODE_FB_MODIFIERS,
+		 .modifier = { DRM_FORMAT_MOD_LINEAR, 0, 0 },
+		 .pitches = { MAX_WIDTH, 0, 0 },
+	}
+},
 { .buffer_created = 1, .name = "X0L2 Normal sizes",
 	.cmd = { .width = 600, .height = 600, .pixel_format = DRM_FORMAT_X0L2,
 		 .handles = { 1, 0, 0 }, .pitches = { 1200, 0, 0 }
-- 
2.44.2

[PATCH v4 RESEND 3/9] drm/tests: Replace strcpy to strscpy on drm_test_framebuffer_create test

[Carlos Eduardo Gallo Filho]

Replace the use of strcpy to strscpy on the test_to_desc of the
drm_test_framebuffer_create test for better security and reliability.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 3ed987423322..4b1884be9d7a 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -409,7 +409,7 @@ static void drm_test_framebuffer_create(struct kunit *test)
 
 static void drm_framebuffer_test_to_desc(const struct drm_framebuffer_test *t, char *desc)
 {
-	strcpy(desc, t->name);
+	strscpy(desc, t->name, KUNIT_PARAM_DESC_SIZE);
 }
 
 KUNIT_ARRAY_PARAM(drm_framebuffer_create, drm_framebuffer_create_cases,
-- 
2.44.2

[PATCH v4 RESEND 4/9] drm/tests: Add test case for drm_internal_framebuffer_create()

[Carlos Eduardo Gallo Filho]

Introduce a test to cover the creation of framebuffer with
modifier on a device that doesn't support it.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
---
v2:
  - Reorder kunit cases alphabetically.
v3:
  - Replace the use of void pointer on drm_framebuffer_test_priv struct.
  - Test return value of drm_internal_framebuffer_create().
  - Change test documentation to don't rely on another test.
v4:
  - Reorder expectation value.
  - Remove unneeded expectation.
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 24 ++++++++++++++++++++
 1 file changed, 24 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 4b1884be9d7a..2ea3abfd5e7a 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -415,8 +415,32 @@ static void drm_framebuffer_test_to_desc(const struct drm_framebuffer_test *t, c
 KUNIT_ARRAY_PARAM(drm_framebuffer_create, drm_framebuffer_create_cases,
 		  drm_framebuffer_test_to_desc);
 
+/* Tries to create a framebuffer with modifiers without drm_device supporting it */
+static void drm_test_framebuffer_modifiers_not_supported(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct drm_framebuffer *fb;
+
+	/* A valid cmd with modifier */
+	struct drm_mode_fb_cmd2 cmd = {
+		.width = MAX_WIDTH, .height = MAX_HEIGHT,
+		.pixel_format = DRM_FORMAT_ABGR8888, .handles = { 1, 0, 0 },
+		.offsets = { UINT_MAX / 2, 0, 0 }, .pitches = { 4 * MAX_WIDTH, 0, 0 },
+		.flags = DRM_MODE_FB_MODIFIERS,
+	};
+
+	priv->buffer_created = false;
+	dev->mode_config.fb_modifiers_not_supported = 1;
+
+	fb = drm_internal_framebuffer_create(dev, &cmd, NULL);
+	KUNIT_EXPECT_EQ(test, priv->buffer_created, false);
+	KUNIT_EXPECT_EQ(test, PTR_ERR(fb), -EINVAL);
+}
+
 static struct kunit_case drm_framebuffer_tests[] = {
 	KUNIT_CASE_PARAM(drm_test_framebuffer_create, drm_framebuffer_create_gen_params),
+	KUNIT_CASE(drm_test_framebuffer_modifiers_not_supported),
 	{ }
 };
 
-- 
2.44.2

[PATCH v4 RESEND 5/9] drm/tests: Add test for drm_framebuffer_check_src_coords()

[Carlos Eduardo Gallo Filho]

Add a parametrized test for the drm_framebuffer_check_src_coords function.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
v2:
  - Order kunit cases alphabetically.
  - Rename check_src_coords_case to drm_framebuffer_check_src_coords_case.
  - Remove unnecessary comments.
  - Add framebuffer size as a parameter and use edge values.
---
 drivers/gpu/drm/drm_framebuffer.c            |  1 +
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 61 ++++++++++++++++++++
 2 files changed, 62 insertions(+)

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index 888aadb6a4ac..9cd85ac789bb 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -99,6 +99,7 @@ int drm_framebuffer_check_src_coords(uint32_t src_x, uint32_t src_y,
 
 	return 0;
 }
+EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_framebuffer_check_src_coords);
 
 /**
  * drm_mode_addfb - add an FB to the graphics configuration
diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 2ea3abfd5e7a..1924e3f9538e 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -10,6 +10,7 @@
 #include <drm/drm_device.h>
 #include <drm/drm_drv.h>
 #include <drm/drm_mode.h>
+#include <drm/drm_framebuffer.h>
 #include <drm/drm_fourcc.h>
 #include <drm/drm_kunit_helpers.h>
 #include <drm/drm_print.h>
@@ -438,7 +439,67 @@ static void drm_test_framebuffer_modifiers_not_supported(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, PTR_ERR(fb), -EINVAL);
 }
 
+/* Parameters for testing drm_framebuffer_check_src_coords function */
+struct drm_framebuffer_check_src_coords_case {
+	const char *name;
+	const int expect;
+	const unsigned int fb_size;
+	const uint32_t src_x;
+	const uint32_t src_y;
+
+	/* Deltas to be applied on source */
+	const uint32_t dsrc_w;
+	const uint32_t dsrc_h;
+};
+
+static const struct drm_framebuffer_check_src_coords_case
+drm_framebuffer_check_src_coords_cases[] = {
+	{ .name = "Success: source fits into fb",
+	  .expect = 0,
+	},
+	{ .name = "Fail: overflowing fb with x-axis coordinate",
+	  .expect = -ENOSPC, .src_x = 1, .fb_size = UINT_MAX,
+	},
+	{ .name = "Fail: overflowing fb with y-axis coordinate",
+	  .expect = -ENOSPC, .src_y = 1, .fb_size = UINT_MAX,
+	},
+	{ .name = "Fail: overflowing fb with source width",
+	  .expect = -ENOSPC, .dsrc_w = 1, .fb_size = UINT_MAX - 1,
+	},
+	{ .name = "Fail: overflowing fb with source height",
+	  .expect = -ENOSPC, .dsrc_h = 1, .fb_size = UINT_MAX - 1,
+	},
+};
+
+static void drm_test_framebuffer_check_src_coords(struct kunit *test)
+{
+	const struct drm_framebuffer_check_src_coords_case *params = test->param_value;
+	const uint32_t src_x = params->src_x;
+	const uint32_t src_y = params->src_y;
+	const uint32_t src_w = (params->fb_size << 16) + params->dsrc_w;
+	const uint32_t src_h = (params->fb_size << 16) + params->dsrc_h;
+	const struct drm_framebuffer fb = {
+		.width  = params->fb_size,
+		.height = params->fb_size
+	};
+	int ret;
+
+	ret = drm_framebuffer_check_src_coords(src_x, src_y, src_w, src_h, &fb);
+	KUNIT_EXPECT_EQ(test, ret, params->expect);
+}
+
+static void
+check_src_coords_test_to_desc(const struct drm_framebuffer_check_src_coords_case *t,
+			      char *desc)
+{
+	strscpy(desc, t->name, KUNIT_PARAM_DESC_SIZE);
+}
+
+KUNIT_ARRAY_PARAM(check_src_coords, drm_framebuffer_check_src_coords_cases,
+		  check_src_coords_test_to_desc);
+
 static struct kunit_case drm_framebuffer_tests[] = {
+	KUNIT_CASE_PARAM(drm_test_framebuffer_check_src_coords, check_src_coords_gen_params),
 	KUNIT_CASE_PARAM(drm_test_framebuffer_create, drm_framebuffer_create_gen_params),
 	KUNIT_CASE(drm_test_framebuffer_modifiers_not_supported),
 	{ }
-- 
2.44.2

[PATCH v4 RESEND 6/9] drm/tests: Add test for drm_framebuffer_cleanup()

[Carlos Eduardo Gallo Filho]

Add a single KUnit test case for the drm_framebuffer_cleanup function.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
v2:
  - Reorder kunit cases alphabetically.
  - Rely on drm_kunit_helper_alloc_device() for mock initialization.
v3:
  - Init framebuffers using drm_framebuffer_init().
  - Add documentation.
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 32 ++++++++++++++++++++
 1 file changed, 32 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 1924e3f9538e..908583d74b20 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -498,8 +498,40 @@ check_src_coords_test_to_desc(const struct drm_framebuffer_check_src_coords_case
 KUNIT_ARRAY_PARAM(check_src_coords, drm_framebuffer_check_src_coords_cases,
 		  check_src_coords_test_to_desc);
 
+/*
+ * Test if drm_framebuffer_cleanup() really pops out the framebuffer object
+ * from device's fb_list and decrement the number of framebuffers for that
+ * device, which is the only things it does.
+ */
+static void drm_test_framebuffer_cleanup(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct list_head *fb_list = &dev->mode_config.fb_list;
+	struct drm_format_info format = { };
+	struct drm_framebuffer fb1 = { .dev = dev, .format = &format };
+	struct drm_framebuffer fb2 = { .dev = dev, .format = &format };
+
+	/* This will result on [fb_list] -> fb2 -> fb1 */
+	drm_framebuffer_init(dev, &fb1, NULL);
+	drm_framebuffer_init(dev, &fb2, NULL);
+
+	drm_framebuffer_cleanup(&fb1);
+
+	/* Now fb2 is the only one element on fb_list */
+	KUNIT_ASSERT_TRUE(test, list_is_singular(&fb2.head));
+	KUNIT_ASSERT_EQ(test, dev->mode_config.num_fb, 1);
+
+	drm_framebuffer_cleanup(&fb2);
+
+	/* Now fb_list is empty */
+	KUNIT_ASSERT_TRUE(test, list_empty(fb_list));
+	KUNIT_ASSERT_EQ(test, dev->mode_config.num_fb, 0);
+}
+
 static struct kunit_case drm_framebuffer_tests[] = {
 	KUNIT_CASE_PARAM(drm_test_framebuffer_check_src_coords, check_src_coords_gen_params),
+	KUNIT_CASE(drm_test_framebuffer_cleanup),
 	KUNIT_CASE_PARAM(drm_test_framebuffer_create, drm_framebuffer_create_gen_params),
 	KUNIT_CASE(drm_test_framebuffer_modifiers_not_supported),
 	{ }
-- 
2.44.2

[PATCH v4 RESEND 7/9] drm/tests: Add test for drm_framebuffer_lookup()

[Carlos Eduardo Gallo Filho]

Add two KUnit test cases for the drm_framebuffer_lookup function, one
for the base case, that tests if the lookup finds the correct framebuffer
object and another that tests the lookup for an inexistent framebuffer.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
v2:
  - Reorder kunit cases alphabetically.
  - Replace drm_mode_object_add() call to drm_framebuffer_init().
  - Rely on drm_kunit_helper_alloc_device() for mock initialization.
v3:
  - Rename framebuffer variables.
  - Add documentation.
  - Split the lookup for inexistent framebuffer into another test.
  - Call drm_framebuffer_put after lookup on drm_test_framebuffer_lookup
    test.
---
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 41 ++++++++++++++++++++
 1 file changed, 41 insertions(+)

diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 908583d74b20..e11b5bc9a105 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -529,10 +529,51 @@ static void drm_test_framebuffer_cleanup(struct kunit *test)
 	KUNIT_ASSERT_EQ(test, dev->mode_config.num_fb, 0);
 }
 
+/*
+ * Initialize a framebuffer, lookup its id and test if the returned reference
+ * matches.
+ */
+static void drm_test_framebuffer_lookup(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct drm_format_info format = { };
+	struct drm_framebuffer expected_fb = { .dev = dev, .format = &format };
+	struct drm_framebuffer *returned_fb;
+	uint32_t id = 0;
+	int ret;
+
+	ret = drm_framebuffer_init(dev, &expected_fb, NULL);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+	id = expected_fb.base.id;
+
+	/* Looking for expected_fb */
+	returned_fb = drm_framebuffer_lookup(dev, NULL, id);
+	KUNIT_EXPECT_PTR_EQ(test, returned_fb, &expected_fb);
+	drm_framebuffer_put(returned_fb);
+
+	drm_framebuffer_cleanup(&expected_fb);
+}
+
+/* Try to lookup an id that is not linked to a framebuffer */
+static void drm_test_framebuffer_lookup_inexistent(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct drm_framebuffer *fb;
+	uint32_t id = 0;
+
+	/* Looking for an inexistent framebuffer */
+	fb = drm_framebuffer_lookup(dev, NULL, id);
+	KUNIT_EXPECT_NULL(test, fb);
+}
+
 static struct kunit_case drm_framebuffer_tests[] = {
 	KUNIT_CASE_PARAM(drm_test_framebuffer_check_src_coords, check_src_coords_gen_params),
 	KUNIT_CASE(drm_test_framebuffer_cleanup),
 	KUNIT_CASE_PARAM(drm_test_framebuffer_create, drm_framebuffer_create_gen_params),
+	KUNIT_CASE(drm_test_framebuffer_lookup),
+	KUNIT_CASE(drm_test_framebuffer_lookup_inexistent),
 	KUNIT_CASE(drm_test_framebuffer_modifiers_not_supported),
 	{ }
 };
-- 
2.44.2

[PATCH v4 RESEND 8/9] drm/tests: Add test for drm_framebuffer_init()

[Carlos Eduardo Gallo Filho]

Add three KUnit test cases for the drm_framebuffer_init function:

1. Test if expected values are being set after drm_framebuffer_init() call.
2. Try to init a framebuffer without setting its format.
3. Try calling drm_framebuffer_init() with mismatch of the drm_device
   passed at the first argument and the one pointed by fb->dev.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
---
v2:
  - Reorder kunit cases alphabetically.
  - Let fb1.dev unset instead of set it to wrong_drm to test mismatched
    drm_device passed as drm_framebuffer_init() argument.
  - Clean the framebuffer object.
v3:
  - Split into three tests.
  - Add documentation.
  - Stop testing lookup here.
v4:
  - Export drm_framebuffer_free for test.
  - Document what is expected on drm_test_framebuffer_init test.
  - Use a valid drm_device on drm_test_framebuffer_init_dev_mismatch test.
---
 drivers/gpu/drm/drm_framebuffer.c            |  1 +
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 84 ++++++++++++++++++++
 2 files changed, 85 insertions(+)

diff --git a/drivers/gpu/drm/drm_framebuffer.c b/drivers/gpu/drm/drm_framebuffer.c
index 9cd85ac789bb..47e6e8577b62 100644
--- a/drivers/gpu/drm/drm_framebuffer.c
+++ b/drivers/gpu/drm/drm_framebuffer.c
@@ -839,6 +839,7 @@ void drm_framebuffer_free(struct kref *kref)
 
 	fb->funcs->destroy(fb);
 }
+EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_framebuffer_free);
 
 /**
  * drm_framebuffer_init - initialize a framebuffer
diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index e11b5bc9a105..72314805839d 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -5,6 +5,7 @@
  * Copyright (c) 2022 Maíra Canal <mairacanal@riseup.net>
  */
 
+#include <kunit/device.h>
 #include <kunit/test.h>
 
 #include <drm/drm_device.h>
@@ -568,10 +569,93 @@ static void drm_test_framebuffer_lookup_inexistent(struct kunit *test)
 	KUNIT_EXPECT_NULL(test, fb);
 }
 
+/*
+ * Test if drm_framebuffer_init initializes the framebuffer successfully,
+ * asserting that its modeset object struct and its refcount are correctly
+ * set and that strictly one framebuffer is initialized.
+ */
+static void drm_test_framebuffer_init(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct drm_format_info format = { };
+	struct drm_framebuffer fb1 = { .dev = dev, .format = &format };
+	struct drm_framebuffer_funcs funcs = { };
+	int ret;
+
+	ret = drm_framebuffer_init(dev, &fb1, &funcs);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+
+	/* Check if fb->funcs is actually set to the drm_framebuffer_funcs passed on */
+	KUNIT_EXPECT_PTR_EQ(test, fb1.funcs, &funcs);
+
+	/* The fb->comm must be set to the current running process */
+	KUNIT_EXPECT_STREQ(test, fb1.comm, current->comm);
+
+	/* The fb->base must be successfully initialized */
+	KUNIT_EXPECT_NE(test, fb1.base.id, 0);
+	KUNIT_EXPECT_EQ(test, fb1.base.type, DRM_MODE_OBJECT_FB);
+	KUNIT_EXPECT_EQ(test, kref_read(&fb1.base.refcount), 1);
+	KUNIT_EXPECT_PTR_EQ(test, fb1.base.free_cb, &drm_framebuffer_free);
+
+	/* There must be just that one fb initialized */
+	KUNIT_EXPECT_EQ(test, dev->mode_config.num_fb, 1);
+	KUNIT_EXPECT_PTR_EQ(test, dev->mode_config.fb_list.prev, &fb1.head);
+	KUNIT_EXPECT_PTR_EQ(test, dev->mode_config.fb_list.next, &fb1.head);
+
+	drm_framebuffer_cleanup(&fb1);
+}
+
+/* Try to init a framebuffer without setting its format */
+static void drm_test_framebuffer_init_bad_format(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct drm_framebuffer fb1 = { .dev = dev, .format = NULL };
+	struct drm_framebuffer_funcs funcs = { };
+	int ret;
+
+	/* Fails if fb.format isn't set */
+	ret = drm_framebuffer_init(dev, &fb1, &funcs);
+	KUNIT_EXPECT_EQ(test, ret, -EINVAL);
+}
+
+/*
+ * Test calling drm_framebuffer_init() passing a framebuffer linked to a
+ * different drm_device parent from the one passed on the first argument, which
+ * must fail.
+ */
+static void drm_test_framebuffer_init_dev_mismatch(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *right_dev = &priv->dev;
+	struct drm_device *wrong_dev;
+	struct device *wrong_dev_parent;
+	struct drm_format_info format = { };
+	struct drm_framebuffer fb1 = { .dev = right_dev, .format = &format };
+	struct drm_framebuffer_funcs funcs = { };
+	int ret;
+
+	wrong_dev_parent = kunit_device_register(test, "drm-kunit-wrong-device-mock");
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, wrong_dev_parent);
+
+	wrong_dev = __drm_kunit_helper_alloc_drm_device(test, wrong_dev_parent,
+							sizeof(struct drm_device),
+							0, 0);
+	KUNIT_ASSERT_NOT_ERR_OR_NULL(test, wrong_dev);
+
+	/* Fails if fb->dev doesn't point to the drm_device passed on first arg */
+	ret = drm_framebuffer_init(wrong_dev, &fb1, &funcs);
+	KUNIT_EXPECT_EQ(test, ret, -EINVAL);
+}
+
 static struct kunit_case drm_framebuffer_tests[] = {
 	KUNIT_CASE_PARAM(drm_test_framebuffer_check_src_coords, check_src_coords_gen_params),
 	KUNIT_CASE(drm_test_framebuffer_cleanup),
 	KUNIT_CASE_PARAM(drm_test_framebuffer_create, drm_framebuffer_create_gen_params),
+	KUNIT_CASE(drm_test_framebuffer_init),
+	KUNIT_CASE(drm_test_framebuffer_init_bad_format),
+	KUNIT_CASE(drm_test_framebuffer_init_dev_mismatch),
 	KUNIT_CASE(drm_test_framebuffer_lookup),
 	KUNIT_CASE(drm_test_framebuffer_lookup_inexistent),
 	KUNIT_CASE(drm_test_framebuffer_modifiers_not_supported),
-- 
2.44.2

Re: [PATCH v4 RESEND 8/9] drm/tests: Add test for drm_framebuffer_init()

[Jani Nikula]

On Tue, 10 Sep 2024, Carlos Eduardo Gallo Filho <gcarlos@disroot.org> wrote:
> +/* Try to init a framebuffer without setting its format */
> +static void drm_test_framebuffer_init_bad_format(struct kunit *test)
> +{
> +	struct drm_framebuffer_test_priv *priv = test->priv;
> +	struct drm_device *dev = &priv->dev;
> +	struct drm_framebuffer fb1 = { .dev = dev, .format = NULL };
> +	struct drm_framebuffer_funcs funcs = { };
> +	int ret;
> +
> +	/* Fails if fb.format isn't set */
> +	ret = drm_framebuffer_init(dev, &fb1, &funcs);

Not only does this fail, it spits a WARN_ON_ONCE() in dmesg. Which in
turn gets flagged as a failure in the test in our CI.

What's the policy with kunit tests causing warnings? I think it's
reasonable for any CI to flag dmesg warnings. We shouldn't be hitting
those. Filtering the warnigs is a tricky business.

BR,
Jani.



> +	KUNIT_EXPECT_EQ(test, ret, -EINVAL);
> +}

-- 
Jani Nikula, Intel

[PATCH v4 RESEND 9/9] drm/tests: Add test for drm_framebuffer_free()

[Carlos Eduardo Gallo Filho]

Add a single KUnit test case for the drm_framebuffer_free function.

Signed-off-by: Carlos Eduardo Gallo Filho <gcarlos@disroot.org>
Acked-by: Maxime Ripard <mripard@kernel.org>
---
v2:
  - Reorder kunit cases alphabetically.
v3:
  - Replace the use of void pointer on drm_framebuffer_test_priv struct.
  - Remove the test with unregistered framebuffer object.
  - Add documentation.
v4:
  - Export drm_mode_object_add for test.
---
 drivers/gpu/drm/drm_mode_object.c            |  1 +
 drivers/gpu/drm/tests/drm_framebuffer_test.c | 50 ++++++++++++++++++++
 2 files changed, 51 insertions(+)

diff --git a/drivers/gpu/drm/drm_mode_object.c b/drivers/gpu/drm/drm_mode_object.c
index df4cc0e8e263..e943205a2394 100644
--- a/drivers/gpu/drm/drm_mode_object.c
+++ b/drivers/gpu/drm/drm_mode_object.c
@@ -81,6 +81,7 @@ int drm_mode_object_add(struct drm_device *dev,
 {
 	return __drm_mode_object_add(dev, obj, obj_type, true, NULL);
 }
+EXPORT_SYMBOL_FOR_TESTS_ONLY(drm_mode_object_add);
 
 void drm_mode_object_register(struct drm_device *dev,
 			      struct drm_mode_object *obj)
diff --git a/drivers/gpu/drm/tests/drm_framebuffer_test.c b/drivers/gpu/drm/tests/drm_framebuffer_test.c
index 72314805839d..6ea04cc8f324 100644
--- a/drivers/gpu/drm/tests/drm_framebuffer_test.c
+++ b/drivers/gpu/drm/tests/drm_framebuffer_test.c
@@ -358,6 +358,7 @@ static const struct drm_framebuffer_test drm_framebuffer_create_cases[] = {
 struct drm_framebuffer_test_priv {
 	struct drm_device dev;
 	bool buffer_created;
+	bool buffer_freed;
 };
 
 static struct drm_framebuffer *fb_create_mock(struct drm_device *dev,
@@ -649,10 +650,59 @@ static void drm_test_framebuffer_init_dev_mismatch(struct kunit *test)
 	KUNIT_EXPECT_EQ(test, ret, -EINVAL);
 }
 
+static void destroy_free_mock(struct drm_framebuffer *fb)
+{
+	struct drm_framebuffer_test_priv *priv = container_of(fb->dev, typeof(*priv), dev);
+
+	priv->buffer_freed = true;
+}
+
+static struct drm_framebuffer_funcs framebuffer_funcs_free_mock = {
+	.destroy = destroy_free_mock,
+};
+
+/*
+ * In summary, the drm_framebuffer_free() function must implicitly call
+ * fb->funcs->destroy() and garantee that the framebufer object is unregistered
+ * from the drm_device idr pool.
+ */
+static void drm_test_framebuffer_free(struct kunit *test)
+{
+	struct drm_framebuffer_test_priv *priv = test->priv;
+	struct drm_device *dev = &priv->dev;
+	struct drm_mode_object *obj;
+	struct drm_framebuffer fb = {
+		.dev = dev,
+		.funcs = &framebuffer_funcs_free_mock,
+	};
+	int id, ret;
+
+	priv->buffer_freed = false;
+
+	/*
+	 * Mock	a framebuffer that was not unregistered	at the moment of the
+	 * drm_framebuffer_free() call.
+	 */
+	ret = drm_mode_object_add(dev, &fb.base, DRM_MODE_OBJECT_FB);
+	KUNIT_ASSERT_EQ(test, ret, 0);
+	id = fb.base.id;
+
+	drm_framebuffer_free(&fb.base.refcount);
+
+	/* The framebuffer object must be unregistered */
+	obj = drm_mode_object_find(dev, NULL, id, DRM_MODE_OBJECT_FB);
+	KUNIT_EXPECT_PTR_EQ(test, obj, NULL);
+	KUNIT_EXPECT_EQ(test, fb.base.id, 0);
+
+	/* Test if fb->funcs->destroy() was called */
+	KUNIT_EXPECT_EQ(test, priv->buffer_freed, true);
+}
+
 static struct kunit_case drm_framebuffer_tests[] = {
 	KUNIT_CASE_PARAM(drm_test_framebuffer_check_src_coords, check_src_coords_gen_params),
 	KUNIT_CASE(drm_test_framebuffer_cleanup),
 	KUNIT_CASE_PARAM(drm_test_framebuffer_create, drm_framebuffer_create_gen_params),
+	KUNIT_CASE(drm_test_framebuffer_free),
 	KUNIT_CASE(drm_test_framebuffer_init),
 	KUNIT_CASE(drm_test_framebuffer_init_bad_format),
 	KUNIT_CASE(drm_test_framebuffer_init_dev_mismatch),
-- 
2.44.2

Re: [PATCH v4 RESEND 0/9] Increase coverage on drm_framebuffer.c

[Maxime Ripard]

On Tue, 10 Sep 2024 21:15:25 -0300, Carlos Eduardo Gallo Filho wrote:
> This patchset includes new KUnit tests for 5 untested functions from
> drm_framebuffer.c and improvements to the existent one.
> 
> The first patch replace the use of dev_private member from drm_device
> mock on the existent test by embedding it into an outer struct containing
> a generic pointer.
> 
> [...]

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

Thanks!
Maxime

Re: [PATCH v4 RESEND 0/9] Increase coverage on drm_framebuffer.c

[Jani Nikula]

On Wed, 11 Sep 2024, Maxime Ripard <mripard@kernel.org> wrote:
> On Tue, 10 Sep 2024 21:15:25 -0300, Carlos Eduardo Gallo Filho wrote:
>> This patchset includes new KUnit tests for 5 untested functions from
>> drm_framebuffer.c and improvements to the existent one.
>> 
>> The first patch replace the use of dev_private member from drm_device
>> mock on the existent test by embedding it into an outer struct containing
>> a generic pointer.
>> 
>> [...]
>
> Applied to misc/kernel.git (drm-misc-next).

How was this series itself tested? It would be prudent to Cc: intel-gfx
on stuff like this to run it through our CI. I don't think it ever
passed [1].

BR,
Jani.


[1] https://intel-gfx-ci.01.org/tree/drm-tip/shards-all.html?testfilter=drm_framebuffer



-- 
Jani Nikula, Intel

Re: [PATCH v4 RESEND 0/9] Increase coverage on drm_framebuffer.c

[Maxime Ripard]

[-- Attachment #1: Type: text/plain, Size: 925 bytes --]

On Fri, Sep 13, 2024 at 10:31:08AM GMT, Jani Nikula wrote:
> On Wed, 11 Sep 2024, Maxime Ripard <mripard@kernel.org> wrote:
> > On Tue, 10 Sep 2024 21:15:25 -0300, Carlos Eduardo Gallo Filho wrote:
> >> This patchset includes new KUnit tests for 5 untested functions from
> >> drm_framebuffer.c and improvements to the existent one.
> >> 
> >> The first patch replace the use of dev_private member from drm_device
> >> mock on the existent test by embedding it into an outer struct containing
> >> a generic pointer.
> >> 
> >> [...]
> >
> > Applied to misc/kernel.git (drm-misc-next).
> 
> How was this series itself tested? It would be prudent to Cc: intel-gfx
> on stuff like this to run it through our CI. I don't think it ever
> passed [1].

I'm not sure what's going on, but:

./tools/testing/kunit/kunit.py run --kunitconfig=drivers/gpu/drm//tests

Works like a charm with this series

Maxime

[-- Attachment #2: signature.asc --]
[-- Type: application/pgp-signature, Size: 273 bytes --]

Re: [PATCH v4 RESEND 0/9] Increase coverage on drm_framebuffer.c

[Jani Nikula]

On Fri, 13 Sep 2024, Maxime Ripard <mripard@kernel.org> wrote:
> On Fri, Sep 13, 2024 at 10:31:08AM GMT, Jani Nikula wrote:
>> On Wed, 11 Sep 2024, Maxime Ripard <mripard@kernel.org> wrote:
>> > On Tue, 10 Sep 2024 21:15:25 -0300, Carlos Eduardo Gallo Filho wrote:
>> >> This patchset includes new KUnit tests for 5 untested functions from
>> >> drm_framebuffer.c and improvements to the existent one.
>> >> 
>> >> The first patch replace the use of dev_private member from drm_device
>> >> mock on the existent test by embedding it into an outer struct containing
>> >> a generic pointer.
>> >> 
>> >> [...]
>> >
>> > Applied to misc/kernel.git (drm-misc-next).
>> 
>> How was this series itself tested? It would be prudent to Cc: intel-gfx
>> on stuff like this to run it through our CI. I don't think it ever
>> passed [1].
>
> I'm not sure what's going on, but:
>
> ./tools/testing/kunit/kunit.py run --kunitconfig=drivers/gpu/drm//tests
>
> Works like a charm with this series

We consistently hit the below warning in drm_framebuffer_free().

Looks like drm_test_framebuffer_free() fails to initialize the
framebuffer, there's no call to drm_framebuffer_init(), leaving
fb->filp_head list uninitialized. The list_empty() check in
drm_framebuffer_free() blows up. Why it doesn't fail for you, I don't
understand.

BR,
Jani.



<4> [131.574236] ------------[ cut here ]------------
<4> [131.574244] drm-kunit-mock-device drm_test_framebuffer_free.drm-kunit-mock-device: [drm] drm_WARN_ON(!list_empty(&fb->filp_head))
<4> [131.574269] WARNING: CPU: 8 PID: 1261 at drivers/gpu/drm/drm_framebuffer.c:832 drm_framebuffer_free+0x71/0x80
<4> [131.574281] Modules linked in: drm_framebuffer_test drm_kunit_helpers kunit vgem drm_shmem_helper snd_hda_codec_hdmi r8153_ecm cdc_ether usbnet i915 x86_pkg_temp_thermal coretemp kvm_intel kvm snd_hda_intel snd_intel_dspcfg mei_gsc_proxy snd_hda_codec prime_numbers crct10dif_pclmul r8152 snd_hwdep i2c_algo_bit crc32_pclmul wmi_bmof mii ghash_clmulni_intel ttm e1000e snd_hda_core video i2c_i801 mei_me drm_display_helper ptp i2c_mux snd_pcm thunderbolt mei drm_buddy pps_core i2c_smbus intel_lpss_pci wmi [last unloaded: drm_framebuffer_test]
<4> [131.574378] CPU: 8 UID: 0 PID: 1261 Comm: kunit_try_catch Tainted: G                 N 6.11.0-rc7-CI_DRM_15393-g2c6794afc551+ #1
<4> [131.574386] Tainted: [N]=TEST
<4> [131.574389] Hardware name: Intel Corporation Meteor Lake Client Platform/MTL-P LP5x T3 RVP, BIOS MTLPFWI1.R00.3471.D91.2401310918 01/31/2024
<4> [131.574393] RIP: 0010:drm_framebuffer_free+0x71/0x80
<4> [131.574400] Code: 4c 8b 6f 50 4d 85 ed 75 03 4c 8b 2f e8 48 c5 03 00 48 c7 c1 88 00 4f 82 4c 89 ea 48 c7 c7 53 8f 45 82 48 89 c6 e8 1f be 80 ff <0f> 0b eb ad 66 66 2e 0f 1f 84 00 00 00 00 00 90 90 90 90 90 90 90
<4> [131.574405] RSP: 0018:ffffc900013efd60 EFLAGS: 00010282
<4> [131.574413] RAX: 0000000000000000 RBX: ffffc900013efdc8 RCX: 0000000000000000
<4> [131.574418] RDX: 0000000000000002 RSI: ffffffff8243ccc2 RDI: 00000000ffffffff
<4> [131.574422] RBP: ffff8881190f9000 R08: 0000000000000000 R09: ffffc900013efb90
<4> [131.574425] R10: 0000000000000001 R11: 0000000000000001 R12: ffffc900013efda0
<4> [131.574429] R13: ffff888114cb9b40 R14: ffffffffa030e520 R15: ffffc9000169f8e0
<4> [131.574434] FS:  0000000000000000(0000) GS:ffff88885fc00000(0000) knlGS:0000000000000000
<4> [131.574441] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
<4> [131.574448] CR2: 000055cc6f2feed0 CR3: 000000000663a002 CR4: 0000000000f70ef0
<4> [131.574455] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
<4> [131.574463] DR3: 0000000000000000 DR6: 00000000ffff07f0 DR7: 0000000000000400
<4> [131.574470] PKRU: 55555554
<4> [131.574477] Call Trace:
<4> [131.574483]  <TASK>
<4> [131.574491]  ? __warn+0x8c/0x190
<4> [131.574505]  ? drm_framebuffer_free+0x71/0x80
<4> [131.574518]  ? report_bug+0x1f8/0x200
<4> [131.574535]  ? prb_read_valid+0x16/0x20
<4> [131.574553]  ? handle_bug+0x3c/0x70
<4> [131.574566]  ? exc_invalid_op+0x18/0x70
<4> [131.574579]  ? asm_exc_invalid_op+0x1a/0x20
<4> [131.574593]  ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [kunit]
<4> [131.574636]  ? drm_framebuffer_free+0x71/0x80
<4> [131.574658]  drm_test_framebuffer_free+0x88/0x220 [drm_framebuffer_test]
<4> [131.574709]  kunit_try_run_case+0x6d/0x150 [kunit]
<4> [131.574724]  ? __kthread_parkme+0x31/0xa0
<4> [131.574732]  ? lockdep_hardirqs_on+0x7b/0x100
<4> [131.574744]  ? __pfx_kunit_generic_run_threadfn_adapter+0x10/0x10 [kunit]
<4> [131.574757]  kunit_generic_run_threadfn_adapter+0x19/0x40 [kunit]
<4> [131.574771]  kthread+0xeb/0x120
<4> [131.574779]  ? __pfx_kthread+0x10/0x10
<4> [131.574788]  ret_from_fork+0x2c/0x50
<4> [131.574796]  ? __pfx_kthread+0x10/0x10
<4> [131.574803]  ret_from_fork_asm+0x1a/0x30
<4> [131.574821]  </TASK>
<4> [131.574824] irq event stamp: 1017
<4> [131.574829] hardirqs last  enabled at (1023): [<ffffffff8113ec40>] console_unlock+0x110/0x120
<4> [131.574841] hardirqs last disabled at (1028): [<ffffffff8113ec25>] console_unlock+0xf5/0x120
<4> [131.574851] softirqs last  enabled at (14): [<ffffffff810a492c>] handle_softirqs+0x2ec/0x3f0
<4> [131.574859] softirqs last disabled at (5): [<ffffffff810a50a7>] irq_exit_rcu+0x87/0xc0
<4> [131.574867] ---[ end trace 0000000000000000 ]---


-- 
Jani Nikula, Intel