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 43BAEC3279D for ; Tue, 13 Oct 2020 02:42:09 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0EAAE221EB for ; Tue, 13 Oct 2020 02:42:09 +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 S1727673AbgJMAdX (ORCPT ); Mon, 12 Oct 2020 20:33:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:47820 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727531AbgJMAdB (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 2EF29C0613E1 for ; Mon, 12 Oct 2020 17:32:36 -0700 (PDT) Received: by mail-pg1-x549.google.com with SMTP id j16so12561728pgi.3 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=CDOn1RfvBxDEPQHt7GX/VUfnYWyaX+NBDhGOYnTpufbeCAb5iK1sirV0X0Ka+Kn70s qw1Uh4QoLFDjbQY5sAUocyFG80Zz4zdNeKBBbMDBt2WCs1aezcjZ4XeaMWPGKOv4D30A 1mCYaceQvCFHYW75C3Sj+8Tld0v5Kou60d4MF4s6o8Odc7MffLUYKoVXiuu9EDF6qzbc 8U7gDYY4xXkl0zxaNQR4q2DyB77hGpSRgzw3VNDP0G95m0Pqc1/ikRg7TyTFygTiDCIg aTHQjtkceEuf1b1A/lEhV/4jnwPVIwlY2/QY6FTxXSSLpE9f8ymMGNytHf2evtWBf0cB jRxQ== X-Gm-Message-State: AOAM533uXKidAgdN0Gese4FIik6jRXXAZK4n3rYYVralYR3qMekqFlQf XXLghv1RMx1NAtTfGDSN6Uw/ADfcFeoluflTbMg= 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-arch@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