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: Thomas Zimmermann <tzimmermann@suse.de>
Fixes: 954907f714 ("drm/shmem-helper: Refactor locked/unlocked functions")
Cc: dri-devel@lists.freedesktop.org
Cc: <stable@vger.kernel.org> # v6.16+
Reviewed-by: Boris Brezillon <boris.brezillon@collabora.com>
Link: https://patch.msgid.link/20251212160317.287409-5-tzimmermann@suse.de
This commit is contained in:
Thomas Zimmermann
2025-12-12 17:00:35 +01:00
parent cda83b099f
commit 607d07d8cc
3 changed files with 20 additions and 4 deletions

View File

@@ -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");

View File

@@ -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 */

View File

@@ -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__ */