From cda83b099f117f2a28a77bf467af934cb39e49cf Mon Sep 17 00:00:00 2001 From: Thomas Zimmermann Date: Fri, 12 Dec 2025 17:00:34 +0100 Subject: [PATCH] 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: Thomas Zimmermann Fixes: 954907f7147d ("drm/shmem-helper: Refactor locked/unlocked functions") Cc: dri-devel@lists.freedesktop.org Cc: # v6.16+ Reviewed-by: Boris Brezillon Link: https://patch.msgid.link/20251212160317.287409-4-tzimmermann@suse.de --- drivers/gpu/drm/drm_gem_shmem_helper.c | 33 ++++++++++++++++++++++ drivers/gpu/drm/tests/drm_gem_shmem_test.c | 6 ++-- include/drm/drm_gem_shmem_helper.h | 9 ++++++ 3 files changed, 46 insertions(+), 2 deletions(-) diff --git a/drivers/gpu/drm/drm_gem_shmem_helper.c b/drivers/gpu/drm/drm_gem_shmem_helper.c index fbd1164174b0..de4de594c78b 100644 --- a/drivers/gpu/drm/drm_gem_shmem_helper.c +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c @@ -15,6 +15,8 @@ #include #endif +#include + #include #include #include @@ -901,6 +903,37 @@ fail_detach: } 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"); diff --git a/drivers/gpu/drm/tests/drm_gem_shmem_test.c b/drivers/gpu/drm/tests/drm_gem_shmem_test.c index 1d50bab51ef3..3e7c6f20fbcc 100644 --- a/drivers/gpu/drm/tests/drm_gem_shmem_test.c +++ b/drivers/gpu/drm/tests/drm_gem_shmem_test.c @@ -19,6 +19,8 @@ #include #include +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); } diff --git a/include/drm/drm_gem_shmem_helper.h b/include/drm/drm_gem_shmem_helper.h index 6b6478f5ca24..a80b5bda9271 100644 --- a/include/drm/drm_gem_shmem_helper.h +++ b/include/drm/drm_gem_shmem_helper.h @@ -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__ */ -- 2.47.3