On Fri, 12 Dec 2025 17:00:34 +0100 Thomas Zimmermann <[email protected]> wrote:
> 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 <[email protected]> > Fixes: 954907f7147d ("drm/shmem-helper: Refactor locked/unlocked functions") > Cc: [email protected] > Cc: <[email protected]> # v6.16+ Reviewed-by: Boris Brezillon <[email protected]> > --- > 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 dc94a27710e5..06ef4e5adb7d 100644 > --- a/drivers/gpu/drm/drm_gem_shmem_helper.c > +++ b/drivers/gpu/drm/drm_gem_shmem_helper.c > @@ -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> > @@ -893,6 +895,37 @@ 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"); > 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 <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); > } > diff --git a/include/drm/drm_gem_shmem_helper.h > b/include/drm/drm_gem_shmem_helper.h > index 589f7bfe7506..6924ee226655 100644 > --- a/include/drm/drm_gem_shmem_helper.h > +++ b/include/drm/drm_gem_shmem_helper.h > @@ -303,4 +303,13 @@ 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__ */
