From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935985AbcHaQl0 convert rfc822-to-8bit (ORCPT ); Wed, 31 Aug 2016 12:41:26 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:48579 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935692AbcHaQgS (ORCPT ); Wed, 31 Aug 2016 12:36:18 -0400 Date: Wed, 31 Aug 2016 18:36:14 +0200 From: Sebastian Andrzej Siewior To: Steven Rostedt Cc: linux-rt-users@vger.kernel.org, linux-kernel@vger.kernel.org, tglx@linutronix.de, netdev@vger.kernel.org Subject: Re: [RT PATCH 1/2] net: add back the missing serialization in ip_send_unicast_reply() Message-ID: <20160831163613.dg5hgb6l2jd5b5ms@linutronix.de> References: <20160831160049.14303-1-bigeasy@linutronix.de> <20160831121553.6aea5cda@gandalf.local.home> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline Content-Transfer-Encoding: 8BIT In-Reply-To: <20160831121553.6aea5cda@gandalf.local.home> User-Agent: NeoMutt/ (1.7.0) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2016-08-31 12:15:53 [-0400], Steven Rostedt wrote: > > @@ -689,10 +691,13 @@ static void tcp_v4_send_reset(const struct sock *sk, struct sk_buff *skb) > > offsetof(struct inet_timewait_sock, tw_bound_dev_if)); > > > > arg.tos = ip_hdr(skb)->tos; > > + > > + local_lock(tcp_sk_lock); > > Interesting that I noticed in mainline, they have: > > local_bh_disable(); > > here. > > I'm surprised we don't have a local_lock_bh() or something to that > effect. Turning local_bh_disable() into local_lock_bh(). One side effect would be that the network driver will be flushed out / waited for completion during socket write (due to the spin_lock_bh()). Not sure how much fun all this will bring. We could try this… > -- Steve Sebastian