From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on gnuweeb.org X-Spam-Level: X-Spam-Status: No, score=-6.2 required=5.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_HI,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.6 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by gnuweeb.org (Postfix) with ESMTPS id C9C0D7E352 for ; Thu, 31 Mar 2022 16:11:53 +0000 (UTC) Authentication-Results: gnuweeb.org; dkim=pass (2048-bit key; unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20201202 header.b=cHfUUa5H; dkim-atps=neutral Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 3BDA3B81B7F; Thu, 31 Mar 2022 16:11:52 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4CA79C340ED; Thu, 31 Mar 2022 16:11:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1648743111; bh=N3LF6qL3b+AkuR6hIqMLAR3Jr6PiseXe5qT4PBdX+mk=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=cHfUUa5H1XS1LBoFh5E8Jikj/qoyrYRNDxg4FxjCbK9VCt2f+nL+GLh8YFk5BoDhi xp6K6VaXd4V/JL1ql466k8YK825gx23O8sqGKj2tyD+FnNrOnjsV17IcLs7ntVMaHJ 8/9k9DK7S3+1bqsM4V/XAqNUp8qc0JIHcAIW5Mlz9wykzwBj3DaG+R/0LDqWCAwQx6 BBYcWChgmbjyOEFD8DalFTFexLrYv/9tYLnpLNdt6DySthBFcbrzM8LDK4Cp78TiU7 c8pWDc9PzUsduolTp74jYtn8fYfFGoSR9wKjta9pJJOLLAMJbTcdGye7Qi0Cw692vZ LZOA9egyyLrrw== Date: Thu, 31 Mar 2022 09:11:43 -0700 From: Nathan Chancellor To: Mike Rapoport Cc: Roman Gushchin , kernel test robot , Roman Gushchin , llvm@lists.linux.dev, kbuild-all@lists.01.org, GNU/Weeb Mailing List , linux-kernel@vger.kernel.org, Suren Baghdasaryan , Andrew Morton , Linux Memory Management List , Minchan Kim , Nick Desaulniers Subject: Re: [ammarfaizi2-block:google/android/kernel/common/android12-trusty-5.10 4036/5872] WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock Message-ID: References: <202203301412.MZ7wQvQz-lkp@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: List-Id: On Thu, Mar 31, 2022 at 12:42:04PM +0300, Mike Rapoport wrote: > (added llvm folks) > > Hi, > > On Wed, Mar 30, 2022 at 02:47:43PM -0700, Roman Gushchin wrote: > > On Wed, Mar 30, 2022 at 02:53:14PM +0800, kbuild test robot wrote: > > > Hi Roman, > > > > > > FYI, the error/warning still remains. > > > > > > tree: https://github.com/ammarfaizi2/linux-block google/android/kernel/common/android12-trusty-5.10 > > > head: 07055bfd3d810d41a38354693dfaa55a6f8c0025 > > > commit: 0e0bfc41fdf4d79d39ebe929844cdee44f97366d [4036/5872] UPSTREAM: mm: cma: allocate cma areas bottom-up > > > config: x86_64-randconfig-a005 (https://download.01.org/0day-ci/archive/20220330/202203301412.MZ7wQvQz-lkp@intel.com/config) > > > compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 0f6d9501cf49ce02937099350d08f20c4af86f3d) > > > reproduce (this is a W=1 build): > > > wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross > > > chmod +x ~/bin/make.cross > > > # https://github.com/ammarfaizi2/linux-block/commit/0e0bfc41fdf4d79d39ebe929844cdee44f97366d > > > git remote add ammarfaizi2-block https://github.com/ammarfaizi2/linux-block > > > git fetch --no-tags ammarfaizi2-block google/android/kernel/common/android12-trusty-5.10 > > > git checkout 0e0bfc41fdf4d79d39ebe929844cdee44f97366d > > > # save the config file to linux build tree > > > mkdir build_dir > > > COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash > > > > > > If you fix the issue, kindly add following tag as appropriate > > > Reported-by: kernel test robot > > > > > > All warnings (new ones prefixed by >>, old ones prefixed by <<): > > > > > > >> WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the variable .meminit.data:memblock > > > The function memblock_bottom_up() references > > > the variable __meminitdata memblock. > > > This is often because memblock_bottom_up lacks a __meminitdata > > > annotation or the annotation of memblock is wrong. > > > > I guess this patch should fix it, however I fail to reproduce the original issue. > > Maybe it's up to the specific compiler version. > > > > -- > > > > From b55a8dd19f4156d7e24ec39b18ede06965ce1c4f Mon Sep 17 00:00:00 2001 > > From: Roman Gushchin > > Date: Wed, 30 Mar 2022 14:42:12 -0700 > > Subject: [PATCH] memblock: fix memblock_bottom_up() and > > memblock_set_bottom_up() annotations > > > > memblock_bottom_up() and memblock_set_bottom_up() lack __meminitdata > > annotations causing compiler warnings like: > > WARNING: modpost: vmlinux.o(.text+0x4111c4): Section mismatch in reference from the function memblock_bottom_up() to the > > variable .meminit.data:memblock > > > > Fix it by adding the missing annotation and removing the wrong > > __meminit annotation. > > > > Reported-by: kernel test robot > > Signed-off-by: Roman Gushchin > > --- > > include/linux/memblock.h | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/include/linux/memblock.h b/include/linux/memblock.h > > index 50ad19662a32..536bc2fc31e6 100644 > > --- a/include/linux/memblock.h > > +++ b/include/linux/memblock.h > > @@ -460,7 +460,7 @@ static inline void *memblock_alloc_node(phys_addr_t size, > > /* > > * Set the allocation direction to bottom-up or top-down. > > */ > > -static inline __init_memblock void memblock_set_bottom_up(bool enable) > > +static inline __initdata_memblock void memblock_set_bottom_up(bool enable) > > I think putting __initdata_memlock won't help here, because there should be > nothing wrong with __meminit function accessing __meminitdata data. > > My guesstimate would be that the compiler decided not to inline this and > still dropped section attribute because of 'inline'. > > If this is the case we I think we should > > s/inline __init_memblock/__always_inline/ > > > { > > memblock.bottom_up = enable; > > } > > @@ -470,7 +470,7 @@ static inline __init_memblock void memblock_set_bottom_up(bool enable) > > * if this is true, that said, memblock will allocate memory > > * in bottom-up direction. > > */ > > -static inline __init_memblock bool memblock_bottom_up(void) > > +static inline __initdata_memblock bool memblock_bottom_up(void) > > { > > return memblock.bottom_up; > > } > > -- > > 2.30.2 > > > For the record, I cannot reproduce this on mainline, which has commits 34dc2efb39a2 ("memblock: fix section mismatch warning") and a024b7c2850d ("mm: memblock: fix section mismatch warning again"). That first commit has the same exact warning as this report, which is against an Android tree (android12-trusty-5.10). While I do not see the commit that 34dc2efb39a2 claims to fix in android12-trusty-5.10, I do see the three commits in android12-5.10: a46e3fa13968 ("UPSTREAM: mm: memblock: drop __init from memblock functions to make it inline") 5f7ec0f4c383 ("UPSTREAM: memblock: fix section mismatch warning") 8cf5bb6946a2 ("UPSTREAM: mm: memblock: fix section mismatch warning again") I think we can just discard this report for now, unless someone from Google's trusty team wants to address it in that branch. Cheers, Nathan