From mboxrd@z Thu Jan 1 00:00:00 1970 From: Eric Dumazet Subject: Re: [PATCH net v2] vxlan: Use RCU apis to access sk_user_data. Date: Tue, 24 Sep 2013 09:16:06 -0700 Message-ID: <1380039366.3165.92.camel@edumazet-glaptop> References: <1380038979-24035-1-git-send-email-pshelar@nicira.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 7bit Cc: netdev@vger.kernel.org, Jesse Gross To: Pravin B Shelar Return-path: Received: from mail-pd0-f173.google.com ([209.85.192.173]:56650 "EHLO mail-pd0-f173.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753096Ab3IXQQJ (ORCPT ); Tue, 24 Sep 2013 12:16:09 -0400 Received: by mail-pd0-f173.google.com with SMTP id p10so4802067pdj.32 for ; Tue, 24 Sep 2013 09:16:08 -0700 (PDT) In-Reply-To: <1380038979-24035-1-git-send-email-pshelar@nicira.com> Sender: netdev-owner@vger.kernel.org List-ID: On Tue, 2013-09-24 at 09:09 -0700, Pravin B Shelar wrote: > Use of RCU api makes vxlan code easier to understand. It also > fixes bug due to missing ACCESS_ONCE() on sk_user_data dereference. > In rare case without ACCESS_ONCE() compiler might omit vs on > sk_user_data dereference. Compiler can use vs as alias for > sk->sk_user_data, resulting in multiple sk_user_data dereference > in rcu read context which could change. > > CC: Jesse Gross > Signed-off-by: Pravin B Shelar > --- > v2: > Use RCU_INIT_POINTER > --- > drivers/net/vxlan.c | 11 ++++------- > include/net/sock.h | 2 ++ > 2 files changed, 6 insertions(+), 7 deletions(-) > > diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c > index d1292fe..1fae0d6 100644 > --- a/drivers/net/vxlan.c > +++ b/drivers/net/vxlan.c > @@ -1,4 +1,4 @@ > -/* > + /* > * VXLAN: Virtual eXtensible Local Area Network > * extra space ?