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=-10.8 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,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 21869C433DB for ; Mon, 15 Feb 2021 19:07:14 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id D403E64E13 for ; Mon, 15 Feb 2021 19:07:13 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230000AbhBOTHN (ORCPT ); Mon, 15 Feb 2021 14:07:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56848 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229954AbhBOTHL (ORCPT ); Mon, 15 Feb 2021 14:07:11 -0500 Received: from mail-lj1-x22e.google.com (mail-lj1-x22e.google.com [IPv6:2a00:1450:4864:20::22e]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id DA2C4C061574 for ; Mon, 15 Feb 2021 11:06:25 -0800 (PST) Received: by mail-lj1-x22e.google.com with SMTP id c17so8132723ljn.0 for ; Mon, 15 Feb 2021 11:06:25 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=cloudflare.com; s=google; h=references:user-agent:from:to:cc:subject:in-reply-to:date :message-id:mime-version; bh=nlK3q0YWLBAVnlXKZxWS33kMLrpccihTVh26VJjnw+I=; b=j7s/++HQuwQ0dPkGJVEFaOkmyPWx89p7HYNinQy2Kw+C+ye83h8lIk+xBpcML2iPLN cdGQSEuotJSUOQ7DRw1BnXUk9c16a40Bj+En3z3QWuCbSU15II+YMyOE2o3yOZgTpyQx IPi5Xc/bjTWf3kr7U0jF5Y82wyhDULg/CRvLg= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:references:user-agent:from:to:cc:subject :in-reply-to:date:message-id:mime-version; bh=nlK3q0YWLBAVnlXKZxWS33kMLrpccihTVh26VJjnw+I=; b=AepUMxC4KJuhEwmWptqzvxGkTMbnoLbRugpiP8d++4xqeYTVk0mPW9IxwFtHsaEPnz 3o6yf6srN5sZtsrJ19EU6TL0md1YQpvgMerBYZMlmAOKKMGpNKOV6esygOciiMC8+0nj X6H6K2uoNANoRN+YH+61KEYbZLY7IaZv7yJxPol4xCoLA3by56f6vgJcD6Utgl+tp8gw Dgi9xe/0FCuX8i8tBKCBVg6OCTrfK2/VEFy3l1M+gtQ+bBWtHUdbmhSq3Zpplxoo/jRu +Ag0wVYWTZ4ZGD5o8xkT81jVRvWMR2sJ4hLVCZUboCeVvZU4jzOmSDkHBJv0Mkji8jZy ZZKQ== X-Gm-Message-State: AOAM530k9ST5x9OS6pDf5+klIQv56S22x76O0oDxl6UkKmTxUVwj7nK5 zC9e5AepUdnxv3l/i7V0us+8rA== X-Google-Smtp-Source: ABdhPJyab84qkpdHElTAbOYC612cZAhEcRlUrwt3krnBenvG4JjD2TkjUL3Eb8ZyTI94tkx/v8DK/w== X-Received: by 2002:a2e:9a0a:: with SMTP id o10mr10444014lji.466.1613415984019; Mon, 15 Feb 2021 11:06:24 -0800 (PST) Received: from cloudflare.com (83.24.183.171.ipv4.supernova.orange.pl. [83.24.183.171]) by smtp.gmail.com with ESMTPSA id o27sm2720795lfi.183.2021.02.15.11.06.23 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 15 Feb 2021 11:06:23 -0800 (PST) References: <20210213214421.226357-1-xiyou.wangcong@gmail.com> <20210213214421.226357-4-xiyou.wangcong@gmail.com> User-agent: mu4e 1.1.0; emacs 27.1 From: Jakub Sitnicki To: Cong Wang Cc: netdev@vger.kernel.org, bpf@vger.kernel.org, duanxiongchun@bytedance.com, wangdongdong.6@bytedance.com, jiang.wang@bytedance.com, Cong Wang , John Fastabend , Daniel Borkmann , Lorenz Bauer Subject: Re: [Patch bpf-next v3 3/5] bpf: compute data_end dynamically with JIT code In-reply-to: <20210213214421.226357-4-xiyou.wangcong@gmail.com> Date: Mon, 15 Feb 2021 20:06:22 +0100 Message-ID: <87k0r940cx.fsf@cloudflare.com> MIME-Version: 1.0 Content-Type: text/plain Precedence: bulk List-ID: X-Mailing-List: bpf@vger.kernel.org On Sat, Feb 13, 2021 at 10:44 PM CET, Cong Wang wrote: > From: Cong Wang > > Currently, we compute ->data_end with a compile-time constant > offset of skb. But as Jakub pointed out, we can actually compute > it in eBPF JIT code at run-time, so that we can competely get > rid of ->data_end. This is similar to skb_shinfo(skb) computation > in bpf_convert_shinfo_access(). > > Suggested-by: Jakub Sitnicki > Cc: John Fastabend > Cc: Daniel Borkmann > Cc: Lorenz Bauer > Signed-off-by: Cong Wang > --- Acked-by: Jakub Sitnicki