From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 59A69C46464 for ; Mon, 13 Aug 2018 16:37:07 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id F206921564 for ; Mon, 13 Aug 2018 16:37:06 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org F206921564 Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=davemloft.net Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1730151AbeHMTUC (ORCPT ); Mon, 13 Aug 2018 15:20:02 -0400 Received: from shards.monkeyblade.net ([23.128.96.9]:54036 "EHLO shards.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728293AbeHMTUC (ORCPT ); Mon, 13 Aug 2018 15:20:02 -0400 Received: from localhost (c-24-20-22-31.hsd1.or.comcast.net [24.20.22.31]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (Client did not present a certificate) (Authenticated sender: davem-davemloft) by shards.monkeyblade.net (Postfix) with ESMTPSA id C82C9145A6BF2; Mon, 13 Aug 2018 09:37:03 -0700 (PDT) Date: Mon, 13 Aug 2018 09:37:02 -0700 (PDT) Message-Id: <20180813.093702.2205532109074390272.davem@davemloft.net> To: zong@andestech.com Cc: rostedt@goodmis.org, mingo@redhat.com, dsahern@gmail.com, netdev@vger.kernel.org, linux-kernel@vger.kernel.org, zongbox@gmail.com, greentime@andestech.com Subject: Re: [PATCH] net: Change the layout of structure trace_event_raw_fib_table_lookup From: David Miller In-Reply-To: <1534127212-13186-1-git-send-email-zong@andestech.com> References: <1534127212-13186-1-git-send-email-zong@andestech.com> X-Mailer: Mew version 6.7 on Emacs 26 / Mule 6.0 (HANACHIRUSATO) Mime-Version: 1.0 Content-Type: Text/Plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Greylist: Sender succeeded SMTP AUTH, not delayed by milter-greylist-4.5.12 (shards.monkeyblade.net [149.20.54.216]); Mon, 13 Aug 2018 09:37:04 -0700 (PDT) Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Zong Li Date: Mon, 13 Aug 2018 10:26:52 +0800 > There is an unalignment access about the structure > 'trace_event_raw_fib_table_lookup'. > > In include/trace/events/fib.h, there is a memory operation which casting > the 'src' data member to a pointer, and then store a value to this > pointer point to. > > p32 = (__be32 *) __entry->src; > *p32 = flp->saddr; > > The offset of 'src' in structure trace_event_raw_fib_table_lookup is not > four bytes alignment. On some architectures, they don't permit the > unalignment access, it need to pay the price to handle this situation in > exception handler. > > Adjust the layout of structure to avoid this case. > > Signed-off-by: Zong Li Applied, with Fixes tag from David added.