Patch "orangefs: free superblock when mount fails" has been added to the 4.10-stable tree

@@ -208,14 +208,19 @@ restart:
 				continue;
 			/*
 			 * Skip ops whose filesystem we don't know about unless
-			 * it is being mounted.
+			 * it is being mounted or unmounted.  It is possible for
+			 * a filesystem we don't know about to be unmounted if
+			 * it fails to mount in the kernel after userspace has
+			 * been sent the mount request.
 			 */
 			/* XXX: is there a better way to detect this? */
 			} else if (ret == -1 &&
 				   !(op->upcall.type ==
 					ORANGEFS_VFS_OP_FS_MOUNT ||
 				     op->upcall.type ==
-					ORANGEFS_VFS_OP_GETATTR)) {
+					ORANGEFS_VFS_OP_GETATTR ||
+				     op->upcall.type ==
+					ORANGEFS_VFS_OP_FS_UMOUNT)) {
 				gossip_debug(GOSSIP_DEV_DEBUG,
 				    "orangefs: skipping op tag %llu %s\n",
 				    llu(op->tag), get_opname_string(op));

@@ -249,6 +249,7 @@ struct orangefs_sb_info_s {
 	char devname[ORANGEFS_MAX_SERVER_ADDR_LEN];
 	struct super_block *sb;
 	int mount_pending;
+	int no_list;
 	struct list_head list;
 };
 

@@ -493,7 +493,7 @@ struct dentry *orangefs_mount(struct fil
 
 	if (ret) {
 		d = ERR_PTR(ret);
-		goto free_op;
+		goto free_sb_and_op;
 	}
 
 	/*

@@ -519,6 +519,9 @@ struct dentry *orangefs_mount(struct fil
 	spin_unlock(&orangefs_superblocks_lock);
 	op_release(new_op);
 
+	/* Must be removed from the list now. */
+	ORANGEFS_SB(sb)->no_list = 0;
+
 	if (orangefs_userspace_version >= 20906) {
 		new_op = op_alloc(ORANGEFS_VFS_OP_FEATURES);
 		if (!new_op)

@@ -533,6 +536,10 @@ struct dentry *orangefs_mount(struct fil
 
 	return dget(sb->s_root);
 
+free_sb_and_op:
+	/* Will call orangefs_kill_sb with sb not in list. */
+	ORANGEFS_SB(sb)->no_list = 1;
+	deactivate_locked_super(sb);
 free_op:
 	gossip_err("orangefs_mount: mount request failed with %d\n", ret);
 	if (ret == -EINVAL) {

@@ -558,12 +565,14 @@ void orangefs_kill_sb(struct super_block
 	 */
 	 orangefs_unmount_sb(sb);
 
-	/* remove the sb from our list of orangefs specific sb's */
-
-	spin_lock(&orangefs_superblocks_lock);
-	__list_del_entry(&ORANGEFS_SB(sb)->list);	/* not list_del_init */
-	ORANGEFS_SB(sb)->list.prev = NULL;
-	spin_unlock(&orangefs_superblocks_lock);
+	if (!ORANGEFS_SB(sb)->no_list) {
+		/* remove the sb from our list of orangefs specific sb's */
+		spin_lock(&orangefs_superblocks_lock);
+		/* not list_del_init */
+		__list_del_entry(&ORANGEFS_SB(sb)->list);
+		ORANGEFS_SB(sb)->list.prev = NULL;
+		spin_unlock(&orangefs_superblocks_lock);
+	}
 
 	/*
 	 * make sure that ORANGEFS_DEV_REMOUNT_ALL loop that might've seen us