diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 828a7ff4aebe..a67323c2d41f 100644
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1202,12 +1202,23 @@ int btrfs_quota_disable(struct btrfs_fs_info *fs_info)
 	int ret = 0;
 
 	/*
-	 * We need to have subvol_sem write locked, to prevent races between
-	 * concurrent tasks trying to disable quotas, because we will unlock
-	 * and relock qgroup_ioctl_lock across BTRFS_FS_QUOTA_ENABLED changes.
+	 * We need to have subvol_sem write locked to prevent races with
+	 * snapshot creation.
 	 */
 	lockdep_assert_held_write(&fs_info->subvol_sem);
 
+	/*
+	 * Lock the cleaner mutex to prevent races with concurrent relocation,
+	 * because relocation may be building backrefs for blocks of the quota
+	 * root while we are deleting the root. This is like dropping fs roots
+	 * of deleted snapshots/subvolumes, we need the same protection.
+	 *
+	 * This also prevents races between concurrent tasks trying to disable
+	 * quotas, because we will unlock and relock qgroup_ioctl_lock across
+	 * BTRFS_FS_QUOTA_ENABLED changes.
+	 */
+	mutex_lock(&fs_info->cleaner_mutex);
+
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
 	if (!fs_info->quota_root)
 		goto out;
@@ -1287,6 +1298,7 @@ out:
 		btrfs_end_transaction(trans);
 	else if (trans)
 		ret = btrfs_end_transaction(trans);
+	mutex_unlock(&fs_info->cleaner_mutex);
 
 	return ret;
 }