Re: [PATCH 2/4] devpts: free sb->s_fs_info after shutting down the super block

Al Viro
2023-08-31T06:31:20Z

On Thu, Aug 31, 2023 at 07:31:55AM +0200, Christoph Hellwig wrote:
> sb->s_fs_info can only be safely freed after generic_shutdown_super was
> called and all access to the super_block has stopped.

Similar to ramfs case; nothing in dentry/inode eviction codepaths is
using anything in ->s_fs_info. And references in tty are holding
an active ref to superblock in question, preventing ->kill_sb(), so
nothing from the outside is going to play with e.g. devpts_{new,kill}_index()
under us.