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=-2.2 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,USER_AGENT_SANE_1 autolearn=no 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 8C4E1C2BA19 for ; Wed, 15 Apr 2020 07:53:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6516B20768 for ; Wed, 15 Apr 2020 07:53:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2635366AbgDOHwi (ORCPT ); Wed, 15 Apr 2020 03:52:38 -0400 Received: from szxga04-in.huawei.com ([45.249.212.190]:2375 "EHLO huawei.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S2635311AbgDOHwT (ORCPT ); Wed, 15 Apr 2020 03:52:19 -0400 Received: from DGGEMS412-HUB.china.huawei.com (unknown [172.30.72.59]) by Forcepoint Email with ESMTP id 9367E530937B7EC367CF; Wed, 15 Apr 2020 15:52:13 +0800 (CST) Received: from [127.0.0.1] (10.173.223.60) by DGGEMS412-HUB.china.huawei.com (10.3.19.212) with Microsoft SMTP Server id 14.3.487.0; Wed, 15 Apr 2020 15:52:11 +0800 Subject: Re: [PATCH -next] bpf: remove set but not used variable 'dst_known' To: Song Liu CC: Alexei Starovoitov , Daniel Borkmann , Martin Lau , Yonghong Song , Andrii Nakryiko , "john.fastabend@gmail.com" , "kpsingh@chromium.org" , "netdev@vger.kernel.org" , "bpf@vger.kernel.org" , "linux-kernel@vger.kernel.org" , "kernel-janitors@vger.kernel.org" References: <20200413113703.194287-1-maowenan@huawei.com> <2b2e0060-ef9b-5541-1108-e28464b47f0a@huawei.com> From: maowenan Message-ID: <8855e82a-88d0-8d1e-e5e0-47e781f9653c@huawei.com> Date: Wed, 15 Apr 2020 15:52:10 +0800 User-Agent: Mozilla/5.0 (Windows NT 10.0; WOW64; rv:68.0) Gecko/20100101 Thunderbird/68.3.0 MIME-Version: 1.0 In-Reply-To: Content-Type: text/plain; charset="utf-8" Content-Language: en-US Content-Transfer-Encoding: 8bit X-Originating-IP: [10.173.223.60] X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2020/4/15 15:23, Song Liu wrote: > > >> On Apr 14, 2020, at 6:37 PM, maowenan wrote: >> >> On 2020/4/15 6:05, Song Liu wrote: >>> >>> >>>> On Apr 13, 2020, at 4:37 AM, Mao Wenan wrote: >>>> >>>> Fixes gcc '-Wunused-but-set-variable' warning: >>>> >>>> kernel/bpf/verifier.c:5603:18: warning: variable ‘dst_known’ >>>> set but not used [-Wunused-but-set-variable] >>>> >>>> It is not used since commit f1174f77b50c ("bpf/verifier: >>>> rework value tracking") >>> >>> The fix makes sense. But I think f1174f77b50c introduced dst_known, >>> so this statement is not accurate. >>> >> thanks for review, yes, f1174f77b50c introduced dst_known, and below commit >> doesn't deference variable dst_known. So I send v2 later? >> 3f50f132d840 ("bpf: Verifier, do explicit ALU32 bounds tracking") > > I don't think we need to back port this to stable. So it is OK not to > include Fixes tag. We can just remove this statement in the commit log. > > bpf-next is not open yet. Please send v2 when bpf-next is open. > > Thanks, > Song > OK, I will do that.