1 files changed, 7 insertions, 1 deletions

diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index ba7042e2390b..17b052ae4653 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -9514,19 +9514,25 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
                 list_move_tail(&em->list, &root->fs_info->pinned_chunks);
         }
         spin_unlock(&block_group->lock);
-        unlock_chunks(root);
 
         if (remove_em) {
                 struct extent_map_tree *em_tree;
 
                 em_tree = &root->fs_info->mapping_tree.map_tree;
                 write_lock(&em_tree->lock);
+                /*
+                 * The em might be in the pending_chunks list, so make sure the
+                 * chunk mutex is locked, since remove_extent_mapping() will
+                 * delete us from that list.
+                 */
                 remove_extent_mapping(em_tree, em);
                 write_unlock(&em_tree->lock);
                 /* once for the tree */
                 free_extent_map(em);
         }
 
+        unlock_chunks(root);
+
         btrfs_put_block_group(block_group);
         btrfs_put_block_group(block_group);