From: Imre Deak <imre.d...@intel.com> In commit be8a42ae60 we inroduced a refcount problem, where on the drm_gem_prime_fd_to_handle() error path we'll call dma_buf_put() for self imported dma buffers.
Fix this by taking a reference on the dma buffer in the .gem_import hook instead of assuming the caller had taken one. Besides fixing the bug this is also more logical. Signed-off-by: Imre Deak <imre.deak at intel.com> Signed-off-by: Dave Airlie <airlied at gmail.com> --- drivers/gpu/drm/drm_prime.c | 8 +++++++- drivers/gpu/drm/exynos/exynos_drm_dmabuf.c | 4 +++- drivers/gpu/drm/i915/i915_gem_dmabuf.c | 5 ++++- drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c | 1 - drivers/gpu/drm/udl/udl_gem.c | 4 ++++ 5 files changed, 18 insertions(+), 4 deletions(-) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index eb7c38d..71f02ff 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -276,7 +276,6 @@ struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, * refcount on gem itself instead of f_count of dmabuf. */ drm_gem_object_reference(obj); - dma_buf_put(dma_buf); return obj; } } @@ -285,6 +284,8 @@ struct drm_gem_object *drm_gem_prime_import(struct drm_device *dev, if (IS_ERR(attach)) return ERR_PTR(PTR_ERR(attach)); + get_dma_buf(dma_buf); + sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); if (IS_ERR_OR_NULL(sgt)) { ret = PTR_ERR(sgt); @@ -305,6 +306,8 @@ fail_unmap: dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL); fail_detach: dma_buf_detach(dma_buf, attach); + dma_buf_put(dma_buf); + return ERR_PTR(ret); } EXPORT_SYMBOL(drm_gem_prime_import); @@ -347,6 +350,9 @@ int drm_gem_prime_fd_to_handle(struct drm_device *dev, goto fail; mutex_unlock(&file_priv->prime.lock); + + dma_buf_put(dma_buf); + return 0; fail: diff --git a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c index ba0a3aa..ff7f2a8 100644 --- a/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c +++ b/drivers/gpu/drm/exynos/exynos_drm_dmabuf.c @@ -235,7 +235,6 @@ struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev, * refcount on gem itself instead of f_count of dmabuf. */ drm_gem_object_reference(obj); - dma_buf_put(dma_buf); return obj; } } @@ -244,6 +243,7 @@ struct drm_gem_object *exynos_dmabuf_prime_import(struct drm_device *drm_dev, if (IS_ERR(attach)) return ERR_PTR(-EINVAL); + get_dma_buf(dma_buf); sgt = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); if (IS_ERR_OR_NULL(sgt)) { @@ -298,6 +298,8 @@ err_unmap_attach: dma_buf_unmap_attachment(attach, sgt, DMA_BIDIRECTIONAL); err_buf_detach: dma_buf_detach(dma_buf, attach); + dma_buf_put(dma_buf); + return ERR_PTR(ret); } diff --git a/drivers/gpu/drm/i915/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/i915_gem_dmabuf.c index 6a5af68..c303de1 100644 --- a/drivers/gpu/drm/i915/i915_gem_dmabuf.c +++ b/drivers/gpu/drm/i915/i915_gem_dmabuf.c @@ -271,7 +271,6 @@ struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev, * refcount on gem itself instead of f_count of dmabuf. */ drm_gem_object_reference(&obj->base); - dma_buf_put(dma_buf); return &obj->base; } } @@ -281,6 +280,8 @@ struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev, if (IS_ERR(attach)) return ERR_CAST(attach); + get_dma_buf(dma_buf); + obj = i915_gem_object_alloc(dev); if (obj == NULL) { ret = -ENOMEM; @@ -300,5 +301,7 @@ struct drm_gem_object *i915_gem_prime_import(struct drm_device *dev, fail_detach: dma_buf_detach(dma_buf, attach); + dma_buf_put(dma_buf); + return ERR_PTR(ret); } diff --git a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c index ac74d1b..1bdf7e1 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c +++ b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c @@ -212,7 +212,6 @@ struct drm_gem_object *omap_gem_prime_import(struct drm_device *dev, * refcount on gem itself instead of f_count of dmabuf. */ drm_gem_object_reference(obj); - dma_buf_put(buffer); return obj; } } diff --git a/drivers/gpu/drm/udl/udl_gem.c b/drivers/gpu/drm/udl/udl_gem.c index 3816270..ef034fa 100644 --- a/drivers/gpu/drm/udl/udl_gem.c +++ b/drivers/gpu/drm/udl/udl_gem.c @@ -303,6 +303,8 @@ struct drm_gem_object *udl_gem_prime_import(struct drm_device *dev, if (IS_ERR(attach)) return ERR_CAST(attach); + get_dma_buf(dma_buf); + sg = dma_buf_map_attachment(attach, DMA_BIDIRECTIONAL); if (IS_ERR(sg)) { ret = PTR_ERR(sg); @@ -322,5 +324,7 @@ fail_unmap: dma_buf_unmap_attachment(attach, sg, DMA_BIDIRECTIONAL); fail_detach: dma_buf_detach(dma_buf, attach); + dma_buf_put(dma_buf); + return ERR_PTR(ret); } -- 1.8.2