From 1c6ceeee6ebbcdf9839dbce00719162591180524 Mon Sep 17 00:00:00 2001 From: "Leo (Sunpeng) Li" Date: Wed, 17 Jan 2018 12:51:08 +0100 Subject: drm/atomic: Fix memleak on ERESTARTSYS during non-blocking commits During a non-blocking commit, it is possible to return before the commit_tail work is queued (-ERESTARTSYS, for example). Since a reference on the crtc commit object is obtained for the pending vblank event when preparing the commit, the above situation will leave us with an extra reference. Therefore, if the commit_tail worker has not consumed the event at the end of a commit, release it's reference. Changes since v1: - Also check for state->event->base.completion being set, to handle the case where stall_checks() fails in setup_crtc_commit(). Changes since v2: - Add a flag to drm_crtc_commit, to prevent dereferencing a freed event. i915 may unreference the state in a worker. Fixes: 24835e442f28 ("drm: reference count event->completion") Cc: # v4.11+ Signed-off-by: Leo (Sunpeng) Li Acked-by: Harry Wentland #v1 Signed-off-by: Maarten Lankhorst Link: https://patchwork.freedesktop.org/patch/msgid/20180117115108.29608-1-maarten.lankhorst@linux.intel.com Reviewed-by: Sean Paul --- include/drm/drm_atomic.h | 9 +++++++++ 1 file changed, 9 insertions(+) (limited to 'include/drm/drm_atomic.h') diff --git a/include/drm/drm_atomic.h b/include/drm/drm_atomic.h index 1c27526c499e..cf13842a6dbd 100644 --- a/include/drm/drm_atomic.h +++ b/include/drm/drm_atomic.h @@ -134,6 +134,15 @@ struct drm_crtc_commit { * &drm_pending_vblank_event pointer to clean up private events. */ struct drm_pending_vblank_event *event; + + /** + * @abort_completion: + * + * A flag that's set after drm_atomic_helper_setup_commit takes a second + * reference for the completion of $drm_crtc_state.event. It's used by + * the free code to remove the second reference if commit fails. + */ + bool abort_completion; }; struct __drm_planes_state { -- cgit