Merge tag 'for-5.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

Pull btrfs fixes from David Sterba:
 "Two regression fixes:

   - hangs caused by a missing barrier in the locking code

   - memory leaks of extent_state due to bad handling of a cached
     pointer"

* tag 'for-5.3-rc1-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux:
  btrfs: fix extent_state leak in btrfs_lock_and_flush_ordered_range
  btrfs: Fix deadlock caused by missing memory barrier

1 files changed, 6 insertions, 3 deletions

diff --git a/fs/btrfs/locking.c b/fs/btrfs/locking.c
index 98fccce4208c..393eceda57c8 100644
--- a/fs/btrfs/locking.c
+++ b/fs/btrfs/locking.c
@@ -346,9 +346,12 @@ void btrfs_tree_unlock(struct extent_buffer *eb)
 	if (blockers) {
 		btrfs_assert_no_spinning_writers(eb);
 		eb->blocking_writers--;
-		/* Use the lighter barrier after atomic */
-		smp_mb__after_atomic();
-		cond_wake_up_nomb(&eb->write_lock_wq);
+		/*
+		 * We need to order modifying blocking_writers above with
+		 * actually waking up the sleepers to ensure they see the
+		 * updated value of blocking_writers
+		 */
+		cond_wake_up(&eb->write_lock_wq);
 	} else {
 		btrfs_assert_spinning_writers_put(eb);
 		write_unlock(&eb->lock);