When userspace mmaps dma-buf's fd, the dma-buf reservation lock must be held. Add locking sanity checks to the dma-buf mmaping callbacks of DRM drivers to ensure that the locking assumptions won't regress in future. Suggested-by: Daniel Vetter <daniel@xxxxxxxx> Signed-off-by: Dmitry Osipenko <dmitry.osipenko@xxxxxxxxxxxxx> --- drivers/gpu/drm/drm_prime.c | 2 ++ drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c | 2 ++ drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c | 2 ++ drivers/gpu/drm/tegra/gem.c | 2 ++ 4 files changed, 8 insertions(+) diff --git a/drivers/gpu/drm/drm_prime.c b/drivers/gpu/drm/drm_prime.c index 20e109a802ae..f924b8b4ab6b 100644 --- a/drivers/gpu/drm/drm_prime.c +++ b/drivers/gpu/drm/drm_prime.c @@ -781,6 +781,8 @@ int drm_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct *vma) struct drm_gem_object *obj = dma_buf->priv; struct drm_device *dev = obj->dev; + dma_resv_assert_held(dma_buf->resv); + if (!dev->driver->gem_prime_mmap) return -ENOSYS; diff --git a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c index ec6f7ae47783..9322ac29008b 100644 --- a/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c +++ b/drivers/gpu/drm/i915/gem/i915_gem_dmabuf.c @@ -97,6 +97,8 @@ static int i915_gem_dmabuf_mmap(struct dma_buf *dma_buf, struct vm_area_struct * struct drm_i915_private *i915 = to_i915(obj->base.dev); int ret; + dma_resv_assert_held(dma_buf->resv); + if (obj->base.size < vma->vm_end - vma->vm_start) return -EINVAL; diff --git a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c index 8e194dbc9506..3abc47521b2c 100644 --- a/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c +++ b/drivers/gpu/drm/omapdrm/omap_gem_dmabuf.c @@ -66,6 +66,8 @@ static int omap_gem_dmabuf_mmap(struct dma_buf *buffer, struct drm_gem_object *obj = buffer->priv; int ret = 0; + dma_resv_assert_held(buffer->resv); + ret = drm_gem_mmap_obj(obj, omap_gem_mmap_size(obj), vma); if (ret < 0) return ret; diff --git a/drivers/gpu/drm/tegra/gem.c b/drivers/gpu/drm/tegra/gem.c index b09b8ab40ae4..979e7bc902f6 100644 --- a/drivers/gpu/drm/tegra/gem.c +++ b/drivers/gpu/drm/tegra/gem.c @@ -694,6 +694,8 @@ static int tegra_gem_prime_mmap(struct dma_buf *buf, struct vm_area_struct *vma) struct drm_gem_object *gem = buf->priv; int err; + dma_resv_assert_held(buf->resv); + err = drm_gem_mmap_obj(gem, gem->size, vma); if (err < 0) return err; -- 2.37.3
