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=-20.4 required=3.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,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 7D2F7C41604 for ; Tue, 13 Oct 2020 02:42:08 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 46B86221FC for ; Tue, 13 Oct 2020 02:42:08 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="CfMw3Lf2" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727661AbgJMAdR (ORCPT ); Mon, 12 Oct 2020 20:33:17 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47818 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727530AbgJMAdB (ORCPT ); Mon, 12 Oct 2020 20:33:01 -0400 Received: from mail-pg1-x549.google.com (mail-pg1-x549.google.com [IPv6:2607:f8b0:4864:20::549]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 2CA9CC0613E0 for ; Mon, 12 Oct 2020 17:32:36 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id c3so13480825pgj.5 for ; Mon, 12 Oct 2020 17:32:36 -0700 (PDT) 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=s6lKkOY6jDvHdKU5rddxnOybuTgb4UG6S62YgATiqsw=; b=CfMw3Lf2RqxuH1gK/LplrUVdrli+0+CHSSkm8IVXoxiERluD9UBxqoVgGLYbB0zcGH fcd+f/qjElRp1j6Jdey9Bh7NDBDe4hB9i6yurpQFinDV80y/ezy2gjJtTugW6x9+TxXB lOD7ufXL8OAxIH+6uzRqxS9SQox8gQ5U7CudTH1hC4sfe/ktNYfAhjsreZIIFTMjFG1C RQt8+AhPqYKsAgf3F+x4HsSqm87l4hiDBx+TxXtL+Ap2+aCO42F+hEV40MZGJK2CkBo8 P4FhwGbSHoh+MmiJ53pkyum1T4qHIVaGpa4LSlzx+7mtM5okXCbjhUku3Y3pd0VFE6Pn ksJg== 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=s6lKkOY6jDvHdKU5rddxnOybuTgb4UG6S62YgATiqsw=; b=TvfajMmccdxxsDjidkbk767Ls+6N1TU++Yf0knRb2V2KCy5hcTmlVWsumO2GXglLUg 9FPtE5R7rTG+E95YgJCfL051NzIyjuHbGSwOFB06HArli+OCyWresoBCur8ZeSZm9g94 leVganKmAoTNmCLYKAVXh32s9QJX039i+pbaBAjd++sWYLf50PqcE1Z/kXZHs8XQhKqW y4cJwwnTKGsn39aaqkBeezf43oE47pNMbD/xkcQVCL5Vmni+RDjsQWe/HF6q50Fbyuv8 bJ3c0laMvJY87M3KQMyFYR4uweIlfiHjj4aehb87OFT/BYvCwazwRzHcYOXARE7z62bg M5rA== X-Gm-Message-State: AOAM530BbrXYEqPxVVQ2uoj4z5onvWU0+O0HOvugSNYM7gT+zkfZN1FY 60fWQ0fbTUGtUacdSwkGcCnA2p1m5BHoVI5K6Ew= X-Google-Smtp-Source: ABdhPJyFxyU35wX46NP9k8EgBAnMCUQ4LjUrf9Ha6HBecKs6BME4DjIGIM9k+HTmfXPW/UAyVK3X9uWCjK1Lv7DEg7U= 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:aa7:8492:0:b029:155:79b1:437a with SMTP id u18-20020aa784920000b029015579b1437amr18970192pfn.26.1602549155518; Mon, 12 Oct 2020 17:32:35 -0700 (PDT) Date: Mon, 12 Oct 2020 17:31:52 -0700 In-Reply-To: <20201013003203.4168817-1-samitolvanen@google.com> Message-Id: <20201013003203.4168817-15-samitolvanen@google.com> Mime-Version: 1.0 References: <20201013003203.4168817-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v6 14/25] kbuild: lto: remove duplicate dependencies from .mod files From: Sami Tolvanen To: Masahiro Yamada , Steven Rostedt Cc: Will Deacon , 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, x86@kernel.org, Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-pci@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 ab0ddf4884fd..96d6c9e18901 100644 --- a/scripts/Makefile.build +++ b/scripts/Makefile.build @@ -266,7 +266,7 @@ 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 -- 2.28.0.1011.ga647a8990f-goog