1 files changed, 19 insertions, 7 deletions

diff --git a/drivers/staging/android/sync.c b/drivers/staging/android/sync.c
index 38e5d3b5ed9..18174f7c871 100644
--- a/drivers/staging/android/sync.c
+++ b/drivers/staging/android/sync.c
@@ -79,27 +79,31 @@ static void sync_timeline_free(struct kref *kref)
 		container_of(kref, struct sync_timeline, kref);
 	unsigned long flags;
 
-	if (obj->ops->release_obj)
-		obj->ops->release_obj(obj);
-
 	spin_lock_irqsave(&sync_timeline_list_lock, flags);
 	list_del(&obj->sync_timeline_list);
 	spin_unlock_irqrestore(&sync_timeline_list_lock, flags);
 
+	if (obj->ops->release_obj)
+		obj->ops->release_obj(obj);
+
 	kfree(obj);
 }
 
 void sync_timeline_destroy(struct sync_timeline *obj)
 {
 	obj->destroyed = true;
+	/*
+	 * Ensure timeline is marked as destroyed before
+	 * changing timeline's fences status.
+	 */
+	smp_wmb();
 
 	/*
-	 * If this is not the last reference, signal any children
-	 * that their parent is going away.
+	 * signal any children that their parent is going away.
 	 */
+	sync_timeline_signal(obj);
 
-	if (!kref_put(&obj->kref, sync_timeline_free))
-		sync_timeline_signal(obj);
+	kref_put(&obj->kref, sync_timeline_free);
 }
 EXPORT_SYMBOL(sync_timeline_destroy);
 
@@ -384,6 +388,7 @@ static void sync_fence_detach_pts(struct sync_fence *fence)
 
 	list_for_each_safe(pos, n, &fence->pt_list_head) {
 		struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list);
+
 		sync_timeline_remove_pt(pt);
 	}
 }
@@ -394,6 +399,7 @@ static void sync_fence_free_pts(struct sync_fence *fence)
 
 	list_for_each_safe(pos, n, &fence->pt_list_head) {
 		struct sync_pt *pt = container_of(pos, struct sync_pt, pt_list);
+
 		sync_pt_free(pt);
 	}
 }
@@ -827,6 +833,7 @@ static long sync_fence_ioctl(struct file *file, unsigned int cmd,
 			     unsigned long arg)
 {
 	struct sync_fence *fence = file->private_data;
+
 	switch (cmd) {
 	case SYNC_IOC_WAIT:
 		return sync_fence_ioctl_wait(fence, arg);
@@ -856,18 +863,21 @@ static const char *sync_status_str(int status)
 static void sync_print_pt(struct seq_file *s, struct sync_pt *pt, bool fence)
 {
 	int status = pt->status;
+
 	seq_printf(s, "  %s%spt %s",
 		   fence ? pt->parent->name : "",
 		   fence ? "_" : "",
 		   sync_status_str(status));
 	if (pt->status) {
 		struct timeval tv = ktime_to_timeval(pt->timestamp);
+
 		seq_printf(s, "@%ld.%06ld", tv.tv_sec, tv.tv_usec);
 	}
 
 	if (pt->parent->ops->timeline_value_str &&
 	    pt->parent->ops->pt_value_str) {
 		char value[64];
+
 		pt->parent->ops->pt_value_str(pt, value, sizeof(value));
 		seq_printf(s, ": %s", value);
 		if (fence) {
@@ -892,6 +902,7 @@ static void sync_print_obj(struct seq_file *s, struct sync_timeline *obj)
 
 	if (obj->ops->timeline_value_str) {
 		char value[64];
+
 		obj->ops->timeline_value_str(obj, value, sizeof(value));
 		seq_printf(s, ": %s", value);
 	} else if (obj->ops->print_obj) {
@@ -1001,6 +1012,7 @@ static void sync_dump(void)
 	for (i = 0; i < s.count; i += DUMP_CHUNK) {
 		if ((s.count - i) > DUMP_CHUNK) {
 			char c = s.buf[i + DUMP_CHUNK];
+
 			s.buf[i + DUMP_CHUNK] = 0;
 			pr_cont("%s", s.buf + i);
 			s.buf[i + DUMP_CHUNK] = c;