Pull btrfs fix from Chris Mason:
"Filipe nailed down a problem where tree log replay would do some work
that orphan code wasn't expecting to be done yet, leading to BUG_ON"
* 'for-linus-4.5' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: fix loading of orphan roots leading to BUG_ON
set_bit(BTRFS_ROOT_ORPHAN_ITEM_INSERTED, &root->state);
err = btrfs_insert_fs_root(root->fs_info, root);
+ /*
+ * The root might have been inserted already, as before we look
+ * for orphan roots, log replay might have happened, which
+ * triggers a transaction commit and qgroup accounting, which
+ * in turn reads and inserts fs roots while doing backref
+ * walking.
+ */
+ if (err == -EEXIST)
+ err = 0;
if (err) {
- BUG_ON(err == -EEXIST);
btrfs_free_fs_root(root);
break;
}