At least drm/i915 expects that the obj->dev pointer is set even in failure paths. Specifically when the shmem initialization fails we call i915_gem_object_free which needs to deref obj->base.dev to get at the slab pointer in the device private structure. And the shmem allocation can easily fail when userspace is hitting open file limits.
Doing the structure init even when the shmem file allocation fails prevents this Oops. Testcase: igt/gem_fd_exhaustion Reported-and-Suggested-by: Linus Torvalds <torva...@linux-foundation.org> Cc: Linus Torvalds <torva...@linux-foundation.org> References: http://lists.freedesktop.org/archives/intel-gfx/2014-January/038433.html Cc: sta...@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vet...@ffwll.ch> --- drivers/gpu/drm/drm_gem.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_gem.c b/drivers/gpu/drm/drm_gem.c index 3ff39bb0402d..31c919903cd0 100644 --- a/drivers/gpu/drm/drm_gem.c +++ b/drivers/gpu/drm/drm_gem.c @@ -129,11 +129,12 @@ int drm_gem_object_init(struct drm_device *dev, { struct file *filp; + drm_gem_private_object_init(dev, obj, size); + filp = shmem_file_setup("drm mm object", size, VM_NORESERVE); if (IS_ERR(filp)) return PTR_ERR(filp); - drm_gem_private_object_init(dev, obj, size); obj->filp = filp; return 0; -- 1.8.1.4 _______________________________________________ Intel-gfx mailing list Intel-gfx@lists.freedesktop.org http://lists.freedesktop.org/mailman/listinfo/intel-gfx
