If ->run() fails, it can either free the data structures it
allocated, or leave that task to ->free() which will be called
on failures.
However:
  md.c calls ->free() even if ->private_data is NULL, which
     causes problems in some personalities.
  raid0.c frees the data, but doesn't clear ->private_data,
     which will become a problem when we fix md.c
So better fix both these issues at once.
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Fixes: 5aa61f427e4979be733e4847b9199ff9cc48a47e
URL: https://bugzilla.kernel.org/show_bug.cgi?id=94381
Signed-off-by: NeilBrown <neilb@suse.de>
        }
        if (err) {
                mddev_detach(mddev);
-               pers->free(mddev, mddev->private);
+               if (mddev->private)
+                       pers->free(mddev, mddev->private);
                module_put(pers->owner);
                bitmap_destroy(mddev);
                return err;
 
        dump_zones(mddev);
 
        ret = md_integrity_register(mddev);
-       if (ret)
-               raid0_free(mddev, conf);
 
        return ret;
 }