From: Herbert Xu <herbert@gondor.apana.org.au>
Date: Thu, 14 May 2015 13:58:24 +0800

The current rhashtable rehash code is buggy and can't deal with
parallel insertions/removals without corrupting the hash table.

This patch disables it by partially reverting
c5adde9468b0714a051eac7f9666f23eb10b61f7 ("netlink: eliminate
nl_sk_hash_lock").

This patch also removes a bogus socket lock introduced by that
very same patch.

Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

Herbert, if you agree with me in the other thread that the lock_sock()
or something like it has to remain, you'll need to respin this.

Thanks.