On Tue, Dec 05, 2023 at 10:44:30PM -0800, Eric Biggers wrote: > There are lots of filesystems that free their ->s_fs_info in ->put_super(). Are > they all wrong? Wrong is the wrong word :) For simple file systems that either don't use block devices, or just the main one set up by the super.c code using ->put_super is perfectly fine. Once a file system does something complicated like setting up their own block devices, or trying to reuse super blocks using custom rules it basically has to free ->s_fs_info in it's own ->kill_sb handler. This whole area is a bit messy unfortunately.