Commit 607d07d8 authored by Thomas Zimmermann's avatar Thomas Zimmermann
Browse files

drm/tests: shmem: Hold reservation lock around madvise 



Acquire and release the GEM object's reservation lock around calls
to the object's madvide operation. The tests use
drm_gem_shmem_madvise_locked(), which led to errors such as show below.

[   58.339389] WARNING: CPU: 1 PID: 1352 at drivers/gpu/drm/drm_gem_shmem_helper.c:499 drm_gem_shmem_madvise_locked+0xde/0x140

Only export the new helper drm_gem_shmem_madvise() for Kunit tests.
This is not an interface 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/20251212160317.287409-5-tzimmermann@suse.de
parent cda83b09

drivers/gpu/drm/drm_gem_shmem_helper.c

+15 −0
Original line number Diff line number Diff line
@@ -932,6 +932,21 @@ void drm_gem_shmem_vunmap(struct drm_gem_shmem_object *shmem, struct iosys_map * 
	dma_resv_unlock(obj->resv);

}

EXPORT_SYMBOL_IF_KUNIT(drm_gem_shmem_vunmap);



int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv)

{

	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_madvise_locked(shmem, madv);

	dma_resv_unlock(obj->resv);



	return ret;

}

EXPORT_SYMBOL_IF_KUNIT(drm_gem_shmem_madvise);

#endif



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

drivers/gpu/drm/tests/drm_gem_shmem_test.c

+4 −4
Original line number Diff line number Diff line
@@ -292,17 +292,17 @@ static void drm_gem_shmem_test_madvise(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_madvise_locked(shmem, 1);

	ret = drm_gem_shmem_madvise(shmem, 1);

	KUNIT_EXPECT_TRUE(test, ret);

	KUNIT_ASSERT_EQ(test, shmem->madv, 1);



	/* Set madv to a negative value */

	ret = drm_gem_shmem_madvise_locked(shmem, -1);

	ret = drm_gem_shmem_madvise(shmem, -1);

	KUNIT_EXPECT_FALSE(test, ret);

	KUNIT_ASSERT_EQ(test, shmem->madv, -1);



	/* Check that madv cannot be set back to a positive value */

	ret = drm_gem_shmem_madvise_locked(shmem, 0);

	ret = drm_gem_shmem_madvise(shmem, 0);

	KUNIT_EXPECT_FALSE(test, ret);

	KUNIT_ASSERT_EQ(test, shmem->madv, -1);

}
@@ -330,7 +330,7 @@ static void drm_gem_shmem_test_purge(struct kunit *test) 
	ret = drm_gem_shmem_is_purgeable(shmem);

	KUNIT_EXPECT_FALSE(test, ret);



	ret = drm_gem_shmem_madvise_locked(shmem, 1);

	ret = drm_gem_shmem_madvise(shmem, 1);

	KUNIT_EXPECT_TRUE(test, ret);



	/* The scatter/gather table will be freed by drm_gem_shmem_free */

include/drm/drm_gem_shmem_helper.h

+1 −0
Original line number Diff line number Diff line
@@ -307,6 +307,7 @@ struct drm_gem_object *drm_gem_shmem_prime_import_no_map(struct drm_device *dev, 
#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);

int drm_gem_shmem_madvise(struct drm_gem_shmem_object *shmem, int madv);

#endif



#endif /* __DRM_GEM_SHMEM_HELPER_H__ */