rhashtable_insert_rehash() requires RCU locks to be held in order
to access ht->tbl and traverse to the last table.
Fixes: ccd57b1bd324 ("rhashtable: Add immediate rehash during insertion")
Signed-off-by: Thomas Graf <tgraf@suug.ch>
Signed-off-by: David S. Miller <davem@davemloft.net>
        if (unlikely(rht_grow_above_100(ht, tbl))) {
 slow_path:
                spin_unlock_bh(lock);
-               rcu_read_unlock();
                err = rhashtable_insert_rehash(ht);
+               rcu_read_unlock();
                if (err)
                        return err;