Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1031429Ab2HIQFn (ORCPT ); Thu, 9 Aug 2012 12:05:43 -0400 Received: from mail-pb0-f46.google.com ([209.85.160.46]:38375 "EHLO mail-pb0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755713Ab2HIQFl (ORCPT ); Thu, 9 Aug 2012 12:05:41 -0400 MIME-Version: 1.0 In-Reply-To: <1344526608.28967.1092.camel@edumazet-glaptop> References: <50215A7E.8000701@linaro.org> <1695034.0lrQgQPOMT@sifl> <1344523833.28967.996.camel@edumazet-glaptop> <5799181.tjlnF0gIh2@sifl> <1344526608.28967.1092.camel@edumazet-glaptop> Date: Thu, 9 Aug 2012 12:05:40 -0400 Message-ID: Subject: Re: [PATCH] ipv4: tcp: security_sk_alloc() needed for unicast_sock From: Eric Paris To: Eric Dumazet Cc: Paul Moore , David Miller , Casey Schaufler , John Stultz , "Serge E. Hallyn" , lkml , James Morris , selinux@tycho.nsa.gov, john.johansen@canonical.com, LSM , netdev Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1305 Lines: 29 On Thu, Aug 9, 2012 at 11:36 AM, Eric Dumazet wrote: > On Thu, 2012-08-09 at 11:07 -0400, Paul Moore wrote: > >> Is is possible to do the call to security_sk_alloc() in the ip_init() function >> or does the per-cpu nature of the socket make this a pain? >> > > Its a pain, if we want NUMA affinity. > > Here, each cpu should get memory from its closest node. I really really don't like it. I won't say NAK, but it is the first and only place in the kernel where I believe we allocate an object and don't allocate the security blob until some random later point in time. If it is such a performance issue to have the security blob in the same numa node, isn't adding a number of branches and putting this function call on every output at least as bad? Aren't we discouraged from GFP_ATOMIC? In __init we can use GFP_KERNEL. This still doesn't fix these sockets entirely. We now have the security blob allocated, but it was never set to something useful. Paul, are you looking into this? This is a bandaide, not a fix.... -Eric -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/