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=-7.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS 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 7AC7FC10DAA for ; Thu, 3 Sep 2020 22:29:42 +0000 (UTC) Received: from mother.openwall.net (mother.openwall.net [195.42.179.200]) by mail.kernel.org (Postfix) with SMTP id C29E220767 for ; Thu, 3 Sep 2020 22:29:41 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=chromium.org header.i=@chromium.org header.b="KHsDbTkW" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org C29E220767 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kernel-hardening-return-19763-kernel-hardening=archiver.kernel.org@lists.openwall.com Received: (qmail 26510 invoked by uid 550); 3 Sep 2020 22:29:36 -0000 Mailing-List: contact kernel-hardening-help@lists.openwall.com; run by ezmlm Precedence: bulk List-Post: List-Help: List-Unsubscribe: List-Subscribe: List-ID: Received: (qmail 26478 invoked from network); 3 Sep 2020 22:29:35 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=TORQKLjaztafBoTASZ16yvu7ARDRy50kM4Q1p96biak=; b=KHsDbTkWXmQI1RfBgYlEulerevLWOO1sRzFxAKb+aNgp895tLmEdR1w+6sTjCDCZIQ EuJ90PfQiTWeI7WLS02zfZZUzAc4XMY1Bk6zzL4EiQ37vuCk2BKlfRTd+vxSIXZp2XCf dIa1eEmzbBXCJesqA0svHofYBt8jl9vdhwQP4= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=TORQKLjaztafBoTASZ16yvu7ARDRy50kM4Q1p96biak=; b=qtbDWigd02mPlFMz7Xdej7jZb+wnpEpF6GUAFMSyoLvpKlyj/BKeTxsToI3Y0V6z0g ZBBnX66BnhvjzqKNqMRkOS5mkSUaVarg5t5tsLevOBqHcesrYtH8Khkvd3qp/5BmgNDS C46n8wfwySsg3k/cUQTGsmeFu7CZhcFUaKDbOKmDUZu1uEWi+AcdHetDbRHHN7sC40KO EtrbsqK86NMBqwya7uhHLBop/JWZvWoa5JqUmNmbLwJwx4rp8JWV5AqFWCMyOwpvKW9v NgvibIbkttzYtb0Ld/+z9nM9RwOStgRR+0+GYDT+2UIok3lXqc7AM1zKI6C9rmb/r9rT +fsQ== X-Gm-Message-State: AOAM5333s5eN6aQnNk16YdVMUd/lFA5tAvvVuEOtWpIHMrgqrguBzCoa sQP5Dk63EvnlgrbxhnuZHGdEAg== X-Google-Smtp-Source: ABdhPJyg38PLw4/4AevyFkWAsUoEy3gRppS9+Cz/SI2Otq8bgnJU/k3kDNd4Q7TVX1+2h1rFxh2rAw== X-Received: by 2002:a63:344f:: with SMTP id b76mr4554312pga.388.1599172163775; Thu, 03 Sep 2020 15:29:23 -0700 (PDT) Date: Thu, 3 Sep 2020 15:29:21 -0700 From: Kees Cook To: Sami Tolvanen Cc: Masahiro Yamada , Will Deacon , Peter Zijlstra , Steven Rostedt , Greg Kroah-Hartman , "Paul E. McKenney" , Nick Desaulniers , clang-built-linux@googlegroups.com, kernel-hardening@lists.openwall.com, linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kbuild@vger.kernel.org, linux-kernel@vger.kernel.org, linux-pci@vger.kernel.org, x86@kernel.org Subject: Re: [PATCH v2 14/28] kbuild: lto: remove duplicate dependencies from .mod files Message-ID: <202009031529.78A2DE9D8@keescook> References: <20200624203200.78870-1-samitolvanen@google.com> <20200903203053.3411268-1-samitolvanen@google.com> <20200903203053.3411268-15-samitolvanen@google.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20200903203053.3411268-15-samitolvanen@google.com> On Thu, Sep 03, 2020 at 01:30:39PM -0700, Sami Tolvanen wrote: > With LTO, llvm-nm prints out symbols for each archive member > separately, which results in a lot of duplicate dependencies in the > .mod file when CONFIG_TRIM_UNUSED_SYMS is enabled. When a module > consists of several compilation units, the output can exceed the > default xargs command size limit and split the dependency list to > multiple lines, which results in used symbols getting trimmed. > > This change removes duplicate dependencies, which will reduce the > probability of this happening and makes .mod files smaller and > easier to read. > > Signed-off-by: Sami Tolvanen Reviewed-by: Kees Cook -- Kees Cook