On 30 March 2016 at 10:40, Daniel Vetter daniel.vetter@ffwll.ch wrote:
The sg table isn't refcounted, there's no corresponding locking for unmapping and drm_map_sg is ok with being called concurrently.
So drop the locking since it doesn't protect anything.
Cc: Inki Dae inki.dae@samsung.com Signed-off-by: Daniel Vetter daniel.vetter@intel.com
drivers/gpu/drm/exynos/exynos_drm_gem.c | 4 ---- 1 file changed, 4 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c index 3b7209335df0..60b9975bb0b1 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_gem.c +++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c @@ -388,16 +388,12 @@ int exynos_gem_map_sgt_with_dma(struct drm_device *drm_dev, { int nents;
mutex_lock(&drm_dev->struct_mutex);nents = dma_map_sg(to_dma_dev(drm_dev), sgt->sgl, sgt->nents, dir); if (!nents) { DRM_ERROR("failed to map sgl with dma.\n");mutex_unlock(&drm_dev->struct_mutex); return nents; }mutex_unlock(&drm_dev->struct_mutex); return 0;
Either my coffee hasn't kicked in or we have a preexisting bug. Namely - we are returning 0, regardless if we hit the above error ? If that's intentional shouldn't there be a comment explaining why ?
-Emil