one of the flags in it is used by ->d_hash()/->d_compare()
Reviewed-by: Christian Brauner <brauner@kernel.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
        int work_queued;                /* non-zero delayed work is queued */
        struct delayed_work sb_work;    /* superblock flush delayed work */
        spinlock_t work_lock;           /* protects sb_work and work_queued */
+       struct rcu_head rcu;
 };
 
 #define AFFS_MOUNT_SF_INTL             0x0001 /* International filesystem. */
 
                affs_brelse(sbi->s_root_bh);
                kfree(sbi->s_prefix);
                mutex_destroy(&sbi->s_bmlock);
-               kfree(sbi);
+               kfree_rcu(sbi, rcu);
        }
 }