As soon as register_filesystem() exits, filesystem can be mounted.  It
is better to present fully operational /proc.
Of course it doesn't matter because /proc is not modular but do it
anyway.
Drop error check, it should be handled by panicking.
Link: http://lkml.kernel.org/r/20180309222709.GA3843@avx2
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
 
 void __init proc_root_init(void)
 {
-       int err;
-
        proc_init_kmemcache();
        set_proc_pid_nlink();
-       err = register_filesystem(&proc_fs_type);
-       if (err)
-               return;
-
        proc_self_init();
        proc_thread_self_init();
        proc_symlink("mounts", NULL, "self/mounts");
        proc_tty_init();
        proc_mkdir("bus", NULL);
        proc_sys_init();
+
+       register_filesystem(&proc_fs_type);
 }
 
 static int proc_root_getattr(const struct path *path, struct kstat *stat,