Commit 4792ba1f authored by Linus Torvalds's avatar Linus Torvalds
Browse files

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
parents 863fa888 a3b46b86

fs/btrfs/locking.c

+6 −3
Original line number Original line Diff line number Diff line
@@ -346,9 +346,12 @@ void btrfs_tree_unlock(struct extent_buffer *eb) 
	if (blockers) {

	if (blockers) {

		btrfs_assert_no_spinning_writers(eb);

		btrfs_assert_no_spinning_writers(eb);

		eb->blocking_writers--;

		eb->blocking_writers--;

		/* Use the lighter barrier after atomic */

		/*

		smp_mb__after_atomic();

		 * We need to order modifying blocking_writers above with

		cond_wake_up_nomb(&eb->write_lock_wq);

		 * actually waking up the sleepers to ensure they see the

		 * updated value of blocking_writers

		 */

		cond_wake_up(&eb->write_lock_wq);

	} else {

	} else {

		btrfs_assert_spinning_writers_put(eb);

		btrfs_assert_spinning_writers_put(eb);

		write_unlock(&eb->lock);

		write_unlock(&eb->lock);

fs/btrfs/ordered-data.c

+6 −5
Original line number Original line Diff line number Diff line
@@ -985,13 +985,14 @@ void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree, 
					struct extent_state **cached_state)

					struct extent_state **cached_state)

{

{

	struct btrfs_ordered_extent *ordered;

	struct btrfs_ordered_extent *ordered;

	struct extent_state *cachedp = NULL;

	struct extent_state *cache = NULL;

	struct extent_state **cachedp = &cache;





	if (cached_state)

	if (cached_state)

		cachedp = *cached_state;

		cachedp = cached_state;





	while (1) {

	while (1) {

		lock_extent_bits(tree, start, end, &cachedp);

		lock_extent_bits(tree, start, end, cachedp);

		ordered = btrfs_lookup_ordered_range(inode, start,

		ordered = btrfs_lookup_ordered_range(inode, start,

						     end - start + 1);

						     end - start + 1);

		if (!ordered) {

		if (!ordered) {
@@ -1001,10 +1002,10 @@ void btrfs_lock_and_flush_ordered_range(struct extent_io_tree *tree, 
			 * aren't exposing it outside of this function

			 * aren't exposing it outside of this function

			 */

			 */

			if (!cached_state)

			if (!cached_state)

				refcount_dec(&cachedp->refs);

				refcount_dec(&cache->refs);

			break;

			break;

		}

		}

		unlock_extent_cached(tree, start, end, &cachedp);

		unlock_extent_cached(tree, start, end, cachedp);

		btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);

		btrfs_start_ordered_extent(&inode->vfs_inode, ordered, 1);

		btrfs_put_ordered_extent(ordered);

		btrfs_put_ordered_extent(ordered);

	}

	}

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