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=-11.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham 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 E8B18C432BE for ; Tue, 31 Aug 2021 17:32:59 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C8FE1610A4 for ; Tue, 31 Aug 2021 17:32:59 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240324AbhHaRdy (ORCPT ); Tue, 31 Aug 2021 13:33:54 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:52140 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235078AbhHaRdx (ORCPT ); Tue, 31 Aug 2021 13:33:53 -0400 Received: from mail-pl1-x631.google.com (mail-pl1-x631.google.com [IPv6:2607:f8b0:4864:20::631]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 893ACC061760 for ; Tue, 31 Aug 2021 10:32:58 -0700 (PDT) Received: by mail-pl1-x631.google.com with SMTP id u1so7284304plq.5 for ; Tue, 31 Aug 2021 10:32:58 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=rkTnEj3ChzJlO/isucTXbatcCaYkpBJdKq7prvC6mwI=; b=HhGTLRmVZYdnVdhrAHYzM9lsXjOIUlrqlHTibD4qCyEdZ213nFKFT06wmlf0G2gZzE Y4u4g/zsf5TGC9uVx8PY2KHbXQkAg4SvIm+M01h/mgfIggys+MFIT9HWcyey+cLvG9R5 ww2WntK2Cwsg88MdIt92vfKhA93i1ypGeAg00= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=rkTnEj3ChzJlO/isucTXbatcCaYkpBJdKq7prvC6mwI=; b=PtJPvVSIm/dFlcI/z3UIUcxUJ3cXUqxvSxeS4lpCeWGJasPcWnr4crdPZJy5FtK/Yf jrs43xSPdKTcirDTET1BV0WFavV7wlJam+Rhue6+GXGDKi3XVgR2VLU+rHoSlAQ1w+Ae eZdzJN2XmBqW+/2PNeI5myA3IbjvGLfCAUQRCsPeQcIADgbB7+yACyGf4vekihWs/Ad0 /O6vZXBC92gzLPF3hT8IaW6ZdzIKLj/NtjsOnQ1BnCLDET9ExgWktzWt7kes8eSPsk4j jkz5RoabcuDpoD+BbV4JbbG1pfp4dU4bAR74O8Wv5F4YRLt+zwmz4wEm3EpeSJwYFyw1 mvfg== X-Gm-Message-State: AOAM533bbMYKTVwTq+iwDcZgQsisk9ySEXkil7bJpvqJeNWkP/LOUydA 3+eay1uDWgcOGJIX0iC72yn98g== X-Google-Smtp-Source: ABdhPJwPPtqvpXwclkQ4+DzkARjQoGHhy/jsY84H8+Bxvv8BK7bQHJLt0Q+7+eH4cjfWvOv9GNkkjg== X-Received: by 2002:a17:902:e88d:b0:136:7033:895c with SMTP id w13-20020a170902e88d00b001367033895cmr5565705plg.70.1630431178004; Tue, 31 Aug 2021 10:32:58 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id d15sm18311058pfh.34.2021.08.31.10.32.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 31 Aug 2021 10:32:57 -0700 (PDT) Date: Tue, 31 Aug 2021 10:32:56 -0700 From: Kees Cook To: Masahiro Yamada Cc: linux-kbuild@vger.kernel.org, Michal Marek , Nick Desaulniers , linux-kernel@vger.kernel.org Subject: Re: [PATCH v2 05/13] kbuild: detect objtool update without using .SECONDEXPANSION Message-ID: <202108311032.F503B07@keescook> References: <20210831074004.3195284-1-masahiroy@kernel.org> <20210831074004.3195284-6-masahiroy@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210831074004.3195284-6-masahiroy@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-kbuild@vger.kernel.org On Tue, Aug 31, 2021 at 04:39:56PM +0900, Masahiro Yamada wrote: > Redo commit 8852c5524029 ("kbuild: Fix objtool dependency for > 'OBJECT_FILES_NON_STANDARD_ := n'") to add the objtool > dependency in a cleaner way. > > Using .SECONDEXPANSION ends up with unreadable code due to escaped > dollars. Also, it is not efficient because the second half of > Makefile.build is parsed twice every time. > > Append the objtool dependency to the *.cmd files at the build time. > > This is what fixdep and gen_ksymdeps.sh already do. So, following the > same pattern seems a natural solution. > > This allows us to drop $$(objtool_deps) entirely. > > Signed-off-by: Masahiro Yamada Okay, so IIUC, this means objtool (and args) now ends up in the .cmd file instead of in the Makefile dep rules? That seems reasonable. Reviewed-by: Kees Cook -- Kees Cook