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 A48ADC433DF for ; Fri, 9 Oct 2020 16:14:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6949222365 for ; Fri, 9 Oct 2020 16:14:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="pMlxmld3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2389804AbgJIQOf (ORCPT ); Fri, 9 Oct 2020 12:14:35 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:41578 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2389740AbgJIQOL (ORCPT ); Fri, 9 Oct 2020 12:14:11 -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 0301FC0613DB for ; Fri, 9 Oct 2020 09:14:10 -0700 (PDT) Received: by mail-qv1-xf4a.google.com with SMTP id 99so6111876qva.1 for ; Fri, 09 Oct 2020 09:14:09 -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=s6lKkOY6jDvHdKU5rddxnOybuTgb4UG6S62YgATiqsw=; b=pMlxmld3pCeN4EpXaJz0+y9pU3tNLKwKdw/i9b8CDTyxgJE8DiSfW29Yqq7JBGxWIB FizISS0KYQroQZpoFLdIyyXd3nJXztABchxusIHIWy/a5hTlIHu+GvXT0Dak2hzrkUjJ WdDihkdOX7Ym7zuj99eoOSHPUk9jyMbUiHTUVR+LB37RzS0xzmdJSExSzfdwPOTpRQqs Hko41qQefXDStXJ0wnIio/QOEBPHRUJpHfbdMUnPtDf8nIFrJGJsMuFTr7Ijuy+Rnr8w 5Kje5MABXGYr93PTUo2dudN83/OT7+B9FnRT3xVgpuwDBOzLWU7bGc3luRAI6rm+jvP4 I/PQ== 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=b7JkE4a2sIOegUl/QGrOGv8Og5GkqsjOF0XjWG1S8wSzQ35foUYNCYZ4zvD6x5Qtd1 3UeAOqrfy7Srcby+/hTq1nhXR9yquGBthwVW2pGeVu9aDHtHrMlakdVJiVnY1h6X0bFU 5i+59Ja0Ky4+ThBYYf8/sca7linJhY93FZG/UvxxWtDGPvCLMtBeDvqn4fQ/jo9155la bKOW/PIE0H1Lyh7IGI1RXXgObiarXJmNAF6gepFBIYLUL+u9FVwgvta3d5X208gFIUVb ipv2Y4P4m5m8YjFuWIxSoiQaLadKCMHGb3VKkqWrdsPFdcScqxMcorNqUDrFP9ZLPrX/ dS+A== X-Gm-Message-State: AOAM531zsWlcfPGqaUubNe1ZUJ+L9jpCuaYoDA2bzTmNQD6cy1Hgehso aA8FMVtl42vCnr7wwG66v7L+ebYx/WINPsv0xqM= X-Google-Smtp-Source: ABdhPJwtu7GyWiP77sMt8wQ3XooLL+aqopqPfkXu+lzFDvHaNiLmrCamv63yyVSFJX0judiLUpHLdy/ZvBz6DQjk6sY= 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:ad4:52c6:: with SMTP id p6mr12101699qvs.38.1602260049095; Fri, 09 Oct 2020 09:14:09 -0700 (PDT) Date: Fri, 9 Oct 2020 09:13:23 -0700 In-Reply-To: <20201009161338.657380-1-samitolvanen@google.com> Message-Id: <20201009161338.657380-15-samitolvanen@google.com> Mime-Version: 1.0 References: <20201009161338.657380-1-samitolvanen@google.com> X-Mailer: git-send-email 2.28.0.1011.ga647a8990f-goog Subject: [PATCH v5 14/29] 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 -- 2.28.0.1011.ga647a8990f-goog