Merge remote-tracking branch 'drm/drm-next' into msm-next-staging

Backmerge drm-next to pull in:

  8f59ee9a570c ("drm/msm/dsi: Adjust probe order")

Signed-off-by: Rob Clark <robdclark@chromium.org>

1 files changed, 14 insertions, 0 deletions

diff --git a/fs/btrfs/async-thread.c b/fs/btrfs/async-thread.c
index 309516e6a968..43c89952b7d2 100644
--- a/fs/btrfs/async-thread.c
+++ b/fs/btrfs/async-thread.c
@@ -234,6 +234,13 @@ static void run_ordered_work(struct __btrfs_workqueue *wq,
 				  ordered_list);
 		if (!test_bit(WORK_DONE_BIT, &work->flags))
 			break;
+		/*
+		 * Orders all subsequent loads after reading WORK_DONE_BIT,
+		 * paired with the smp_mb__before_atomic in btrfs_work_helper
+		 * this guarantees that the ordered function will see all
+		 * updates from ordinary work function.
+		 */
+		smp_rmb();
 
 		/*
 		 * we are going to call the ordered done function, but
@@ -317,6 +324,13 @@ static void btrfs_work_helper(struct work_struct *normal_work)
 	thresh_exec_hook(wq);
 	work->func(work);
 	if (need_order) {
+		/*
+		 * Ensures all memory accesses done in the work function are
+		 * ordered before setting the WORK_DONE_BIT. Ensuring the thread
+		 * which is going to executed the ordered work sees them.
+		 * Pairs with the smp_rmb in run_ordered_work.
+		 */
+		smp_mb__before_atomic();
 		set_bit(WORK_DONE_BIT, &work->flags);
 		run_ordered_work(wq, work);
 	} else {