From: Ørjan Eide orjan.eide@arm.com
The copied sync_pt was activated immediately. If the sync_pt was signaled before the entire merge was completed, the new fence's pt_list could be iterated over while it is still in the process of being created.
Moving the the sync_pt_activate call for all new sync_pts to after both the sync_fence_copy_pts and the sync_fence_merge_pts calls ensure that the pt_list is complete and immutable before it can be reached from the timeline's active list.
Cc: Maarten Lankhorst maarten.lankhorst@canonical.com Cc: Erik Gilling konkers@android.com Cc: Daniel Vetter daniel.vetter@ffwll.ch Cc: Rob Clark robclark@gmail.com Cc: Sumit Semwal sumit.semwal@linaro.org Cc: Greg KH gregkh@linuxfoundation.org Cc: dri-devel@lists.freedesktop.org Cc: Android Kernel Team kernel-team@android.com Signed-off-by: Erik Gilling konkers@android.com Signed-off-by: John Stultz john.stultz@linaro.org --- drivers/staging/android/sync.c | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-)
diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c index 1ddc404..bd18c75 100644 --- a/drivers/staging/android/sync.c +++ b/drivers/staging/android/sync.c @@ -324,7 +324,6 @@ static int sync_fence_copy_pts(struct sync_fence *dst, struct sync_fence *src)
new_pt->fence = dst; list_add(&new_pt->pt_list, &dst->pt_list_head); - sync_pt_activate(new_pt); }
return 0; @@ -357,7 +356,6 @@ static int sync_fence_merge_pts(struct sync_fence *dst, struct sync_fence *src) new_pt->fence = dst; list_replace(&dst_pt->pt_list, &new_pt->pt_list); - sync_pt_activate(new_pt); sync_pt_free(dst_pt); } collapsed = true; @@ -373,7 +371,6 @@ static int sync_fence_merge_pts(struct sync_fence *dst, struct sync_fence *src)
new_pt->fence = dst; list_add(&new_pt->pt_list, &dst->pt_list_head); - sync_pt_activate(new_pt); } }
@@ -454,6 +451,7 @@ struct sync_fence *sync_fence_merge(const char *name, struct sync_fence *a, struct sync_fence *b) { struct sync_fence *fence; + struct list_head *pos; int err;
fence = sync_fence_alloc(name); @@ -468,6 +466,12 @@ struct sync_fence *sync_fence_merge(const char *name, if (err < 0) goto err;
+ list_for_each(pos, &fence->pt_list_head) { + struct sync_pt *pt = + container_of(pos, struct sync_pt, pt_list); + sync_pt_activate(pt); + } + /* * signal the fence in case one of it's pts were activated before * they were activated