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=-1.1 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,MAILING_LIST_MULTI,SPF_PASS,URIBL_BLOCKED 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 A3DD6C04ABB for ; Tue, 11 Sep 2018 14:10:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 472AD20880 for ; Tue, 11 Sep 2018 14:10:18 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="Mj6UNKzo" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 472AD20880 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-kernel-owner@vger.kernel.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727746AbeIKTJq (ORCPT ); Tue, 11 Sep 2018 15:09:46 -0400 Received: from mail.kernel.org ([198.145.29.99]:57458 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726689AbeIKTJp (ORCPT ); Tue, 11 Sep 2018 15:09:45 -0400 Received: from devbox (NE2965lan1.rev.em-net.ne.jp [210.141.244.193]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4648D2087F; Tue, 11 Sep 2018 14:10:14 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1536675015; bh=lpypdIJMUc/ueYUTDZs/Ry0F0/ITDhjKN5Mf4yv+grg=; h=Date:From:To:Cc:Subject:In-Reply-To:References:From; b=Mj6UNKzokGO8y+ajy2Wpwu6Rjzvz+b7Tx2cevM3saQ+O5NAzHDoSeFbseUwOBUEsW ncHy1hrxcFc0atgsNQZ8189b5wv3mflyytXOYaDGjB9QFtIxfKiaEuKA0Aj6aw16dR 78i84JcaMWqSTFD5xit0jB3FPo0vipiu9o+ycjj8= Date: Tue, 11 Sep 2018 23:10:12 +0900 From: Masami Hiramatsu To: Masami Hiramatsu Cc: Peter Oberparleiter , Stephen Rothwell , "Steven Rostedt (VMware)" , Linux-Next Mailing List , Linux Kernel Mailing List , arnd@arndb.de Subject: Re: linux-next: build warnings from the build of Linus' tree Message-Id: <20180911231012.fdc45840f3d91860daa2e180@kernel.org> In-Reply-To: <20180911204925.8b6dbbfd9e48369d931cafa2@kernel.org> References: <20180824133206.4218c2e5@canb.auug.org.au> <20180824172053.20fa197294f51496dcec5605@kernel.org> <20180824204756.e787765461975cd1e27502dc@kernel.org> <20180824224211.2934d7c0@canb.auug.org.au> <20180826171058.e07f99e6e03f7497e5a46ed3@kernel.org> <20180828072333.36af4d5d@canb.auug.org.au> <20180828094341.d20d8fbcb9dca310d44df951@kernel.org> <20180907014209.49e2940f74615a1e4f544ffd@kernel.org> <20180908125749.9c903e507a33046d5586e841@kernel.org> <1de08f6a-7c9e-1a75-e3bd-e8bcf99f5e35@linux.ibm.com> <20180911204925.8b6dbbfd9e48369d931cafa2@kernel.org> X-Mailer: Sylpheed 3.5.1 (GTK+ 2.24.31; x86_64-redhat-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 11 Sep 2018 20:49:25 +0900 Masami Hiramatsu wrote: > On Mon, 10 Sep 2018 15:27:20 +0200 > Peter Oberparleiter wrote: > > > On 08.09.2018 05:57, Masami Hiramatsu wrote: > > > On Fri, 7 Sep 2018 14:50:59 +0200 > > > Peter Oberparleiter wrote: > > > > > >> On 06.09.2018 18:42, Masami Hiramatsu wrote: > > >>> Peter Oberparleiter wrote: > > >>>> I've attached a quick fix that should address both problems. I'd > > >>>> appreciate if this patch could get some testing before I post proper fix > > >>>> patches. > > >>> > > >>> Hmm, I'm still not able to reproduce it on powerpc cross build even with > > >>> CONFIG_LD_DEAD_CODE_DATA_ELIMINATION=y ... So, sorry I couldn't test this patch. > > >> > > >> Maybe this is related to the compiler/binutils versions used. I'm using > > >> Fedora 28's gcc-powerpc64 and binutils-powerpc64 packages: > > >> > > >> powerpc64-linux-gnu-gcc (GCC) 7.1.1 20170622 (Red Hat Cross 7.1.1-3) > > >> GNU ld version 2.29.1-4.fc28 > > >> > > >> For reference I'm also attaching the config that I used to reproduce the > > >> problem on kernel v4.18. > > >> > > >>>> diff --git a/arch/arm/kernel/vmlinux.lds.h b/arch/arm/kernel/vmlinux.lds.h > > >>>> index ae5fdff18406..2ca33277a28b 100644 > > >>>> --- a/arch/arm/kernel/vmlinux.lds.h > > >>>> +++ b/arch/arm/kernel/vmlinux.lds.h > > >>>> @@ -48,6 +48,7 @@ > > >>>> > > >>>> #define ARM_DISCARD \ > > >>>> *(.ARM.exidx.exit.text) \ > > >>>> + *(.ARM.exidx.text.exit) \ > > >>> > > >>> BTW, why would we need this? > > >> > > >> That's necessary to fix one of the two ARM linker failures reported via > > >> https://lkml.org/lkml/2018/8/24/345 > > >> > > >>>>> `.text.exit' referenced in section `.ARM.exidx.text.exit' of > > >>>>> kernel/trace/trace_clock.o: defined in discarded section `.text.exit' > > >>>>> of kernel/trace/trace_clock.o > > >> > > >> Section ".ARM.exidx.text.exit" refers to ".text.exit" which was > > >> discarded. With the change above, the extraneous section > > >> ".ARM.exidx.text.exit" is also discarded, resolving the linker failure. > > > > > > OK, so your patch fixes following issue too? > > > > > > https://patchwork.kernel.org/patch/10584685/ > > > > Yes it does, by discarding the text.exit section unconditionally. I > > don't think we need to keep any exit-related section introduced by GCOV > > profiling. It is my understanding that the code contained in such a > > section is only relevant for user-space profiling, to process profiling > > data when a program ends. > > > > Also discarding .ARM.exidx.text.exit seems to be more consistent to how > > .ARM.exidx.exit.text is handled. > > > > > In that case, we should drop above patch. > > > > Yes, I agree. > > Hm, with your patch (on linus tree), I still have this error on arm cross build. > > CC init/version.o > AR init/built-in.a > AR built-in.a > LD vmlinux.o > MODPOST vmlinux.o > `.exit.text' referenced in section `.alt.smp.init' of net/dns_resolver/dns_key.o: defined in discarded section `.exit.text' of net/dns_resolver/dns_key.o Ah, sorry, this is not from GCOV, but alternatives for SMP. This should be a different issue. > > I attached my config. > > Since this comes from section discarding, with my patch (which prevent discarding) this error didn't happen. So, this is just a side effect. your patch is good when CONFIG_DNS_RESOLVER=n Thank you, -- Masami Hiramatsu