From patchwork Wed Nov 18 22:07:20 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sami Tolvanen X-Patchwork-Id: 11916015 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=-26.2 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, URIBL_BLOCKED,USER_AGENT_GIT,USER_IN_DEF_DKIM_WL autolearn=unavailable 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 2D9F9C83011 for ; Wed, 18 Nov 2020 22:08:47 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id BEC1B206CA for ; Wed, 18 Nov 2020 22:08:46 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="tgB3HeaM" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727352AbgKRWHu (ORCPT ); Wed, 18 Nov 2020 17:07:50 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:53806 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727315AbgKRWHq (ORCPT ); Wed, 18 Nov 2020 17:07:46 -0500 Received: from mail-yb1-xb4a.google.com (mail-yb1-xb4a.google.com [IPv6:2607:f8b0:4864:20::b4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5E7F6C061A48 for ; Wed, 18 Nov 2020 14:07:46 -0800 (PST) Received: by mail-yb1-xb4a.google.com with SMTP id w8so4620047ybq.4 for ; Wed, 18 Nov 2020 14:07:46 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20161025; h=sender:date:in-reply-to:message-id:mime-version:references:subject :from:to:cc; bh=tITgh0Ssflf3KIdl9iLTasR/nuysgEKXGj2aGzu0djg=; b=tgB3HeaMLte4FwdwEskpNo3M1G5NMSWdaU3NGnSytOclNILrFVdkD4YBIH/89JtDHP XW414KEtYQqChtXVzZCo6FESh8Tttug6ipG4Xwymb06bhNxw7eh44JTB82tQMjdgKeKe mvE5QooVVjUOl15f8Ufkoo4CuDQMkoEAowvId9Xo6ILJqfJzsuuAiniFNxOTXgItR15s eH6Dk79v+bV/G/7k27PzU2M0pCmQclWaJYIJjA3ojY/R+Z8tO+3QxQrtlIwXnz5RyeCM j8ggYjzxLirUlC9AaKsU1v+JkHXIBzxtLSTtx1qvPQUhEgNQSe/pESJS3QjFV5EMv/+O IZUA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:sender:date:in-reply-to:message-id:mime-version :references:subject:from:to:cc; bh=tITgh0Ssflf3KIdl9iLTasR/nuysgEKXGj2aGzu0djg=; b=F0MX8NP3+G7dlQo8UxaHp/dxQNHCmdLqrLUT25tLTa4hCWBCwafU5Bshu9z+acbXRi IKWiEltoEiHadwWd1h3tREzjLk2GWnu/1tp9dzRf0nZVlvTKzLd2cBEVUoY5HDIwLEgu aaMtouEI4/orgb1vFVyLA7/SU31F9Ydy6Jaz5bsKm6GXujPgu37VCqCgIwOSj1TWFg/A Kyosto9DMatf8jWIc4A6PvKBNpWmWTXKH6NZDYo+oAv/AJYEXAHqr1geYMmI9pkQ6uKP QNEhRug8VcXqODGvou34MxXs2LDlPts1xOJT+J/xDpfVYBfLW6+o1mztfJKnUdjPU0gQ 8AGw== X-Gm-Message-State: AOAM530O54OtYl2thi3tyt/kwmdUw+p419BlcNTKGUBYL+5GJtRqXpeV 9Au81LHTsGzajdmeRyX2X+e2q7vGETeKwP+n2ww= X-Google-Smtp-Source: ABdhPJyru6u4Sy3c6z545hXKz2Lse9yOurfwR7Sqj4soym8ldc5jriOTeAoDW2j8p87AYgdDtayu2H1jxl4fDBYzugo= Sender: "samitolvanen via sendgmr" X-Received: from samitolvanen1.mtv.corp.google.com ([2620:15c:201:2:f693:9fff:fef4:1b6d]) (user=samitolvanen job=sendgmr) by 2002:a5b:c0e:: with SMTP id f14mr12957716ybq.83.1605737265629; Wed, 18 Nov 2020 14:07:45 -0800 (PST) Date: Wed, 18 Nov 2020 14:07:20 -0800 In-Reply-To: <20201118220731.925424-1-samitolvanen@google.com> Message-Id: <20201118220731.925424-7-samitolvanen@google.com> Mime-Version: 1.0 References: <20201118220731.925424-1-samitolvanen@google.com> X-Mailer: git-send-email 2.29.2.454.gaff20da3a2-goog Subject: [PATCH v7 06/17] kbuild: lto: remove duplicate dependencies from .mod files From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt , Will Deacon Cc: Josh Poimboeuf , Peter Zijlstra , Greg Kroah-Hartman , "Paul E. McKenney" , Kees Cook , 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, Sami Tolvanen Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org 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 --- scripts/Makefile.build | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/scripts/Makefile.build b/scripts/Makefile.build index eae2f5386a03..f80ada58271d 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -281,7 +281,7 @@ endef # List module undefined symbols (or empty line if not enabled) ifdef CONFIG_TRIM_UNUSED_KSYMS -cmd_undef_syms = $(NM) $< | sed -n 's/^ *U //p' | xargs echo +cmd_undef_syms = $(NM) $< | sed -n 's/^ *U //p' | sort -u | xargs echo else cmd_undef_syms = echo endif