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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 013D5C433EF for ; Fri, 27 May 2022 12:38:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1350250AbiE0MiX (ORCPT ); Fri, 27 May 2022 08:38:23 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54600 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1348285AbiE0MiA (ORCPT ); Fri, 27 May 2022 08:38:00 -0400 Received: from conssluserg-05.nifty.com (conssluserg-05.nifty.com [210.131.2.90]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 35FAA1A7D04; Fri, 27 May 2022 05:20:24 -0700 (PDT) Received: from mail-pj1-f45.google.com (mail-pj1-f45.google.com [209.85.216.45]) (authenticated) by conssluserg-05.nifty.com with ESMTP id 24RCK0Mp012972; Fri, 27 May 2022 21:20:00 +0900 DKIM-Filter: OpenDKIM Filter v2.10.3 conssluserg-05.nifty.com 24RCK0Mp012972 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=nifty.com; s=dec2015msa; t=1653654001; bh=0D8p3lAezW7RCHWFuSl3YlxjjAyflRfSwWRcaMWkB1c=; h=References:In-Reply-To:From:Date:Subject:To:Cc:From; b=YdyRY+2dyUfImPC1CKqYW2U3nkc4Vi67h6buZPOiM0cTWD/FNHUMUNH3QQpmf6cdW hFhPQiMGftXLxEi38W7uuOVx5T5L4X0jM6fhLbsLgtRikL3CHX7Lsf+EeaCHesMDM/ FQ65vUHST7tuq/Wufs59hF2Hfto47jKBQY5/JFpxF2odBLwCPMeNnf2k+BF5LW1xvH e7UJq9lrrjqyI1eaX6h6S2c5+Mjk7Tq24M+aDm4Q1aHB6+HcaemGmUpaRT4onqqyhQ 0jhVhfqmX/JMoG1p1GVoFGr8q0FQiKsIRJ3Ff7033+FfudRFpiuoyeQdBUdqrMuov+ cmwUUKevRJauw== X-Nifty-SrcIP: [209.85.216.45] Received: by mail-pj1-f45.google.com with SMTP id n10so4443489pjh.5; Fri, 27 May 2022 05:20:00 -0700 (PDT) X-Gm-Message-State: AOAM532rzoapZpCnj7o74HuW6axuEFAgQrY1IT2LoEn4UwLEJwgRS0Dv 3qaEnIMW9H6IDh7HXvbPEIL8RMM7Q/1Nsq/lsMU= X-Google-Smtp-Source: ABdhPJyNuurAZSU4RrV/gNR0QM3ve15YafhODDVnWIldoX3OuLp3Sxx6/a4nkhk1XJRUudsZ6XCW0PfgoO64SnZS+cU= X-Received: by 2002:a17:903:1205:b0:15e:8cbc:fd2b with SMTP id l5-20020a170903120500b0015e8cbcfd2bmr43023919plh.99.1653653999799; Fri, 27 May 2022 05:19:59 -0700 (PDT) MIME-Version: 1.0 References: <20220523142431.10ff2f77@canb.auug.org.au> <20220523154758.11668628@canb.auug.org.au> <20220523162307.45dycvqld7maaj7l@treble> <20220527044711.hrqxx5gz3jghydax@treble> In-Reply-To: From: Masahiro Yamada Date: Fri, 27 May 2022 21:18:37 +0900 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: linux-next: manual merge of the tip tree with the kbuild tree To: Josh Poimboeuf Cc: Stephen Rothwell , Thomas Gleixner , Ingo Molnar , "H. Peter Anvin" , Peter Zijlstra , Josh Poimboeuf , Linux Kernel Mailing List , Linux Next Mailing List Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, May 27, 2022 at 3:04 PM Masahiro Yamada wrote: > > On Fri, May 27, 2022 at 1:47 PM Josh Poimboeuf wrote: > > > > On Fri, May 27, 2022 at 11:19:02AM +0900, Masahiro Yamada wrote: > > > [1] original behavior in Josh's commit > > > > > > $ git checkout 753da4179d08b625d8df72e97724e22749969fd3 > > > $ make defconfig > > > $ make -j8 kernel/ > > > $ head -n 1 kernel/.fork.o.cmd > > > > > > > > > I do not see the "--linked" parameter in the objtool command. > > > > > > > > > > > > > > > [2] behavior in linux-next > > > > > > > > > $ git checkout next-20220523 > > > $ make defconfig > > > $ make -j8 kernel/ > > > $ head -n 1 kernel/.fork.o.cmd > > > > > > I see the "--linked" parameter in the objtool command. > > > > > > kernel/fork.o is a direct output from GCC, > > > not from linker. > > > > Yes, good catch. That flag should only be used for linked objects like > > vmlinux.o or some_module.o. > > > > Objtool only runs on such objects when CONFIG_LTO_CLANG, > > CONFIG_X86_KERNEL_IBT, or CONFIG_NOINSTR_VALIDATION (vmlinux.o-only) is > > enabled. > > > > -- > > Josh > > > When CONFIG_LTO_CLANG=y or CONFIG_X86_KERNEL_IBT=y > is "--linked" necessary for single-object modules? > > > "single-object module" means a module that consists of only one object. > > See this figure: > https://patchwork.kernel.org/project/linux-kbuild/patch/20220513113930.10488-6-masahiroy@kernel.org/ > > > > > In your commit, --linked is passed to all *.prelink.o > whether it consists of a single object or links > multiple objects. Anyway, please let me clean up this part in the kbuild tree: https://patchwork.kernel.org/project/linux-kbuild/patch/20220527100155.1996314-2-masahiroy@kernel.org/ -- Best Regards Masahiro Yamada