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=-20.9 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 F2786C47426 for ; Tue, 29 Sep 2020 21:47:16 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id A37052083B for ; Tue, 29 Sep 2020 21:47:16 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="J0iZkzh/" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728930AbgI2VrM (ORCPT ); Tue, 29 Sep 2020 17:47:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48352 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728892AbgI2VrL (ORCPT ); Tue, 29 Sep 2020 17:47:11 -0400 Received: from mail-qv1-xf4a.google.com (mail-qv1-xf4a.google.com [IPv6:2607:f8b0:4864:20::f4a]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id D9CD4C0613D5 for ; Tue, 29 Sep 2020 14:47:09 -0700 (PDT) Received: by mail-qv1-xf4a.google.com with SMTP id r16so3330820qvn.18 for ; Tue, 29 Sep 2020 14:47:09 -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=SD1yF5YD1LCllhQ+wHxnWDGScJRWPVuGZBuH/1UV7E0=; b=J0iZkzh/GjzAvSvvMSQSffvTtscp77TuS/rOOUU4WJ9pgFewxPSYIc3SuYF5TYZa3f nnJs5NE+Z7HnfV7im6jer/93vPDjH2tAsMsDCCOkNJH1RmXE5K6MIkNKUWtTL0TsRGwX qAdqdJq3CyXfTerbts+lbY6m8AMjwxizFh09pkc2952byTSLnpnpLEsH+VeTxDQPhQlK KJc/bEwAWARFDxCjnLIpypY36iZV6YBpeoMe0S3Fhkxk2EnpJ3bKxAnnRVKOCtJywZ8S cn4idbWnDoWjvaMpJXjclpVdG1XxH/TZB3j/SaC5oSMROSGKYvddyUIYzmMFA/b7OTLC QNvA== 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=SD1yF5YD1LCllhQ+wHxnWDGScJRWPVuGZBuH/1UV7E0=; b=hL+bbRI32BptxAU4PQSy8YbuT3YFMeZikLz8VrIAwiz9XThrh25NTcr8dW1vX53bPq 7ATAGmFKsbKWemYZfPC/14vsRYKwuRfoE8cdQTsNMnD5VYkJjOemxx4ySXnZQTRDAIUQ 6p8IfhF+9rXtJuJmJubqSaVWqdebnHRlryBX8QPAcEbfG/ubumwzXhOWcxwvA5zDkcxK Gybhs+AzsY8XpR6ZYuLVGmlTbZiYovfCjWG4QoqSFLnbCksJxxiWxV/65WVYbMkg+19H PcL2+YARgRmAPxhXOMIh+WR7EsGtjysP572o07/qOa67AKny98CorSfo+QvR2UCfNJ0Y wWvQ== X-Gm-Message-State: AOAM533lTt7x/f9qdQU3H4uHxfj6uDxZSqNa4Gqo8pFFWsKSESrll+qy qGoAl2HB+VDeXFk3guozdgEAlHicVdpzjwfi9pw= X-Google-Smtp-Source: ABdhPJy7ECnfWEGwUFe6hxmbM3YxQNxU/8qssaAcXSiWxNNwaQyUUyZL5rJnjOfK3ZrxDFzMzY/3wIlsYUo/Me039B4= 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:ad4:55ce:: with SMTP id bt14mr6729584qvb.2.1601416029039; Tue, 29 Sep 2020 14:47:09 -0700 (PDT) Date: Tue, 29 Sep 2020 14:46:18 -0700 In-Reply-To: <20200929214631.3516445-1-samitolvanen@google.com> Message-Id: <20200929214631.3516445-17-samitolvanen@google.com> Mime-Version: 1.0 References: <20200929214631.3516445-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.709.gb0816b6eb0-goog Subject: [PATCH v4 16/29] kbuild: lto: remove duplicate dependencies from .mod files From: Sami Tolvanen To: Masahiro Yamada , Will Deacon , Steven Rostedt Cc: 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 -- 2.28.0.709.gb0816b6eb0-goog