Commit cda83b09 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/tests: shmem: Hold reservation lock around vmap/vunmap 



Acquire and release the GEM object's reservation lock around vmap and
vunmap operations. The tests use vmap_locked, which led to errors such
as show below.

[  122.292030] WARNING: CPU: 3 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:390 drm_gem_shmem_vmap_locked+0x3a3/0x6f0

[  122.468066] WARNING: CPU: 3 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:293 drm_gem_shmem_pin_locked+0x1fe/0x350

[  122.563504] WARNING: CPU: 3 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:234 drm_gem_shmem_get_pages_locked+0x23c/0x370

[  122.662248] WARNING: CPU: 2 PID: 1413 at drivers/gpu/drm/drm_gem_shmem_helper.c:452 drm_gem_shmem_vunmap_locked+0x101/0x330

Only export the new vmap/vunmap helpers for Kunit tests. These are
not interfaces for regular drivers.

Signed-off-by: default avatarThomas Zimmermann <tzimmermann@suse.de>
Fixes: 954907f7 ("drm/shmem-helper: Refactor locked/unlocked functions")
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.16+
Reviewed-by: default avatarBoris Brezillon <boris.brezillon@collabora.com>
Link: https://patch.msgid.link/20251212160317.287409-4-tzimmermann@suse.de
parent b47b9ece

drivers/gpu/drm/drm_gem_shmem_helper.c

+33 −0
Original line number Diff line number Diff line
@@ -15,6 +15,8 @@ 
#include <asm/set_memory.h>

#endif



#include <kunit/visibility.h>



#include <drm/drm.h>

#include <drm/drm_device.h>

#include <drm/drm_drv.h>
@@ -901,6 +903,37 @@ struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev, 
}

EXPORT_SYMBOL_GPL(drm_gem_shmem_prime_import_no_map);



/*

 * Kunit helpers

 */



#if IS_ENABLED(CONFIG_KUNIT)

int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map)

{

	struct drm_gem_object *obj = &shmem->base;

	int ret;



	ret = dma_resv_lock_interruptible(obj->resv, NULL);

	if (ret)

		return ret;

	ret = drm_gem_shmem_vmap_locked(shmem, map);

	dma_resv_unlock(obj->resv);



	return ret;

}

EXPORT_SYMBOL_IF_KUNIT(drm_gem_shmem_vmap);



void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map)

{

	struct drm_gem_object *obj = &shmem->base;



	dma_resv_lock_interruptible(obj->resv, NULL);

	drm_gem_shmem_vunmap_locked(shmem, map);

	dma_resv_unlock(obj->resv);

}

EXPORT_SYMBOL_IF_KUNIT(drm_gem_shmem_vunmap);

#endif



MODULE_DESCRIPTION("DRM SHMEM memory-management helpers");

MODULE_IMPORT_NS("DMA_BUF");

MODULE_LICENSE("GPL v2");

drivers/gpu/drm/tests/drm_gem_shmem_test.c

+4 −2
Original line number Diff line number Diff line
@@ -19,6 +19,8 @@ 
#include <drm/drm_gem_shmem_helper.h>

#include <drm/drm_kunit_helpers.h>



MODULE_IMPORT_NS("EXPORTED_FOR_KUNIT_TESTING");



#define TEST_SIZE		SZ_1M

#define TEST_BYTE		0xae
@@ -176,7 +178,7 @@ static void drm_gem_shmem_test_vmap(struct kunit *test) 
	ret = kunit_add_action_or_reset(test, drm_gem_shmem_free_wrapper, shmem);

	KUNIT_ASSERT_EQ(test, ret, 0);



	ret = drm_gem_shmem_vmap_locked(shmem, &map);

	ret = drm_gem_shmem_vmap(shmem, &map);

	KUNIT_ASSERT_EQ(test, ret, 0);

	KUNIT_ASSERT_NOT_NULL(test, shmem->vaddr);

	KUNIT_ASSERT_FALSE(test, iosys_map_is_null(&map));
@@ -186,7 +188,7 @@ static void drm_gem_shmem_test_vmap(struct kunit *test) 
	for (i = 0; i < TEST_SIZE; i++)

		KUNIT_EXPECT_EQ(test, iosys_map_rd(&map, i, u8), TEST_BYTE);



	drm_gem_shmem_vunmap_locked(shmem, &map);

	drm_gem_shmem_vunmap(shmem, &map);

	KUNIT_EXPECT_NULL(test, shmem->vaddr);

	KUNIT_EXPECT_EQ(test, refcount_read(&shmem->vmap_use_count), 0);

}

include/drm/drm_gem_shmem_helper.h

+9 −0
Original line number Diff line number Diff line
@@ -300,4 +300,13 @@ struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev, 
	.gem_prime_import       = drm_gem_shmem_prime_import_no_map, \

	.dumb_create            = drm_gem_shmem_dumb_create



/*

 * Kunit helpers

 */



#if IS_ENABLED(CONFIG_KUNIT)

int drm_gem_shmem_vmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);

void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct iosys_map *map);

#endif



#endif /* __DRM_GEM_SHMEM_HELPER_H__ */