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 384BFC433EF for ; Sun, 22 May 2022 22:35:33 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230170AbiEVWfb (ORCPT ); Sun, 22 May 2022 18:35:31 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34028 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230101AbiEVWfa (ORCPT ); Sun, 22 May 2022 18:35:30 -0400 Received: from mail-il1-x12b.google.com (mail-il1-x12b.google.com [IPv6:2607:f8b0:4864:20::12b]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B3BEE369C0; Sun, 22 May 2022 15:35:28 -0700 (PDT) Received: by mail-il1-x12b.google.com with SMTP id t13so1877845ilm.9; Sun, 22 May 2022 15:35:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20210112; h=mime-version:references:in-reply-to:reply-to:from:date:message-id :subject:to:cc; bh=2E7OE1cam9DtyiuG6iuZuYzKDSzejDf2vjxv7Odi/Sk=; b=oqMNGYd47nfrDiDSIzYpcdQ4Cya1qiPvQyxWXTzoexUfoTbZYP2ONrxer27Ff1kglf rh6bubHsMW2JBReMn8bauYwpxzu3VArJhjyoH+wodFEQuLlQGDKlpV9OUospAZp2cbix 0oCyjcYyZDDPdewWUXI61UpzqcWOM9Hn3BPjE2gL+52yB6KuTNg0oNTTXFhhZX58Z7JT 52tYfaYx43FdjYwMVWRuC7FmB+2f7KO1L8Fqnegb+jy3rTcEDucd9LAp1CkCIjBK4mye wgKBLql7hzY3ZlOu3gNOwienBdTq+UvVqR4cYTUIYDfFt/Kxi/7bJ70mOwyNOriaCRPX Igvg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:mime-version:references:in-reply-to:reply-to :from:date:message-id:subject:to:cc; bh=2E7OE1cam9DtyiuG6iuZuYzKDSzejDf2vjxv7Odi/Sk=; b=ve28bzYzBS4lYFnBoejIoaC3xrx57bO5Nrp9DUpoKcuTHscwIC8weoEQV+lwPlQSlF yPs2ASiUhzWdyPPYxxi5G9aQEbJ/qc3FgGm3r0NWXxrBV3v840sDALOKHzc3ufzB6a5a DktZl+KNizb1b0ULEYyB6Nh1hJyfoct8RwGehdIVHx9LvliIB2EI14kKWifycIZ/Zy8O 8iVq5bHaNoj3WbB7tLtVCUHSTTghXWkFjo8koglgnMx4p37Ij+lscWfaO7cntayp1tkh OqqJJc60uoGKfLYFD23g4TV0IaVITSvotksbbRyPLFhbA+PY0YbdFtPRY4VT6YAlF8r9 4//w== X-Gm-Message-State: AOAM5321TmSeIAUAMOPSbMm6OzjvCDc2Q/4/HioytWEgmnYYPoKp1zwY 5fqTc+oSN3+ts22nUgxe6B7vsyODyLEGuzV7w/HKiBwIYLTsuw== X-Google-Smtp-Source: ABdhPJySklQVLvFbAp1hkug5aSL80QEN+5u0W6ifGPaPLk/2fsDEAFFujE9DDiD4hRG9gCxYPn0dBsPLpEHdqh9VFoE= X-Received: by 2002:a92:d149:0:b0:2d1:5bd:1ec2 with SMTP id t9-20020a92d149000000b002d105bd1ec2mr10042266ilg.100.1653258927993; Sun, 22 May 2022 15:35:27 -0700 (PDT) MIME-Version: 1.0 References: <20220513113930.10488-1-masahiroy@kernel.org> In-Reply-To: Reply-To: sedat.dilek@gmail.com From: Sedat Dilek Date: Mon, 23 May 2022 00:34:51 +0200 Message-ID: Subject: Re: [PATCH v6 00/10] kbuild: yet another series of cleanups (modpost, LTO, MODULE_REL_CRCS, export.h) To: Masahiro Yamada Cc: Linux Kbuild mailing list , Linux Kernel Mailing List , Nathan Chancellor , Nick Desaulniers , Nicolas Schier , Peter Zijlstra , linux-modules , clang-built-linux , Ard Biesheuvel , Sami Tolvanen Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: On Sun, May 22, 2022 at 6:18 PM Sedat Dilek wrote: > > On Sun, May 22, 2022 at 6:10 PM Masahiro Yamada wrote: > > > > On Sun, May 22, 2022 at 11:16 PM Sedat Dilek wrote: > > > > > > On Sun, May 22, 2022 at 11:45 AM Sedat Dilek wrote: > > > > > > > > On Sun, May 22, 2022 at 8:50 AM Masahiro Yamada wrote: > > > > > > > > > > On Sun, May 22, 2022 at 10:45 AM Sedat Dilek wrote: > > > > > > > > > > > > On Fri, May 13, 2022 at 4:31 PM Masahiro Yamada wrote: > > > > > > > > > > > > > > On Fri, May 13, 2022 at 8:42 PM Masahiro Yamada wrote: > > > > > > > > > > > > > > > > > > > > > > > > This is the third batch of cleanups in this development cycle. > > > > > > > > > > > > > > > > > > > > > > > > > > > > > This series is available at > > > > > > > git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild.git > > > > > > > lto-cleanup-v6 > > > > > > > > > > > > > > > > > > > Hi Masahiro, > > > > > > > > > > > > I cloned the repository on top of latest Linus Git. > > > > > > > > > > > > Not able to boot in Quemu - Not able to boot on bare metal. > > > > > > > > > > > > $ grep module_layout log_quemu-5.18.0-rc7-2-amd64-clang14-lto.txt > > > > > > 366:[ 2.173265] floppy: disagrees about version of symbol module_layout > > > > > > 367:[ 2.198746] scsi_common: disagrees about version of symbol module_layout > > > > > > 368:[ 2.205573] i2c_piix4: disagrees about version of symbol module_layout > > > > > > 369:[ 2.210610] psmouse: disagrees about version of symbol module_layout > > > > > > 370:[ 2.225138] scsi_common: disagrees about version of symbol module_layout > > > > > > 371:[ 2.235536] scsi_common: disagrees about version of symbol module_layout > > > > > > 375:Begin: Running /scripts/local-premount ... [ 2.298555] > > > > > > crc32c_intel: disagrees about version of symbol module_layout > > > > > > 376:[ 2.303335] crc32c_generic: disagrees about version of symbol > > > > > > module_layout > > > > > > 377:[ 2.306667] libcrc32c: disagrees about version of symbol module_layout > > > > > > > > > > > > Infos: LLVM-14 + CONFIG_LTO_CLANG_THIN=y > > > > > > > > > > > > My linux-config and qemu-log are attached. > > > > > > > > > > > > > > > > > > > > > Thanks for your testing. > > > > > > > > > > I was also able to reproduce this issue. > > > > > > > > > > > > > > > The problematic parts are: > > > > > > > > > > [ 2.298555] crc32c_intel: disagrees about version of symbol module_layout > > > > > [ 2.303335] crc32c_generic: disagrees about version of symbol module_layout > > > > > [ 2.306667] libcrc32c: disagrees about version of symbol module_layout > > > > > > > > > > > > > > > > > > > > When CONFIG_LTO_CLANG_THIN=y, > > > > > I cannot see any __crc_* symbols in "nm vmlinux". > > > > > > > > > > Perhaps, LTO might have discarded all the __crc_* symbols > > > > > from vmlinux, but I am still checking the details... > > > > > > > > > > > > > Thanks for taking care. > > > > > > > > Just for the records: > > > > > > > > $ grep CONFIG_MODVERSIONS /boot/config-5.18.0-rc7-2-amd64-clang14-lto > > > > CONFIG_MODVERSIONS=y > > > > > > > > > > Did not try CONFIG_MODVERSIONS=n. > > > > > > We have a new file: > > > > > > [ include/linux/export-internal.h ] > > > /* SPDX-License-Identifier: GPL-2.0-only */ > > > /* > > > * Please do not include this explicitly. > > > * This is used by C files generated by modpost. > > > */ > > > > > > #ifndef __LINUX_EXPORT_INTERNAL_H__ > > > #define __LINUX_EXPORT_INTERNAL_H__ > > > > > > #include > > > #include > > > > > > #define SYMBOL_CRC(sym, crc, sec) \ > > > u32 __section("___kcrctab" sec "+" #sym) __crc_##sym = crc > > > > > > #endif /* __LINUX_EXPORT_INTERNAL_H__ */ > > > > > > But we discard __kcrctab in scripts/module.lds.S file. > > > > > > No. > > scripts/module.lds.S keeps __kcrctab. > > > > > > The discarded sections are specified a few lines above: > > > > /DISCARD/ : { > > *(.discard) > > *(.discard.*) > > SANITIZER_DISCARDS > > } > > > > > > > > > > > > > > > > > > > > > Maybe we need: > > > > > > No. > > > > The problem is __crc_* symbols are dropped from vmlinux > > when CONFIG_LTO_CLANG=y. > > > > > > Please try this fixup: > > https://lore.kernel.org/linux-kbuild/20220522160117.599023-1-masahiroy@kernel.org/T/#u > > > > Thanks! > > Will give it a try - will report in a few hours. > > -Sedat- I was able to build and boot on bare metal. Feel free to add my... Reported-by: Sedat Dilek Tested-by: Sedat Dilek # LLVM-14 (x86-64) -Sedat- > > > > > > > > > > > > > > > > > $ git diff scripts/module.lds.S > > > diff --git a/scripts/module.lds.S b/scripts/module.lds.S > > > index 1d0e1e4dc3d2..c04b596c364b 100644 > > > --- a/scripts/module.lds.S > > > +++ b/scripts/module.lds.S > > > @@ -21,8 +21,6 @@ SECTIONS { > > > > > > __ksymtab 0 : { *(SORT(___ksymtab+*)) } > > > __ksymtab_gpl 0 : { *(SORT(___ksymtab_gpl+*)) } > > > - __kcrctab 0 : { *(SORT(___kcrctab+*)) } > > > - __kcrctab_gpl 0 : { *(SORT(___kcrctab_gpl+*)) } > > > > > > .ctors 0 : ALIGN(8) { *(SORT(.ctors.*)) *(.ctors) } > > > .init_array 0 : ALIGN(8) { *(SORT(.init_array.*)) > > > *(.init_array) } > > > > > > Or even? > > > > > > $ git diff scripts/kallsyms.c > > > diff --git a/scripts/kallsyms.c b/scripts/kallsyms.c > > > index 8caabddf817c..fb3601fe8aa3 100644 > > > --- a/scripts/kallsyms.c > > > +++ b/scripts/kallsyms.c > > > @@ -109,7 +109,6 @@ static bool is_ignored_symbol(const char *name, char type) > > > static const char * const ignored_prefixes[] = { > > > "$", /* local symbols for ARM, MIPS, etc. */ > > > ".L", /* local labels, > > > .LBB,.Ltmpxxx,.L__unnamed_xx,.LASANPC, etc. */ > > > - "__crc_", /* modversions */ > > > "__efistub_", /* arm64 EFI stub namespace */ > > > "__kvm_nvhe_", /* arm64 non-VHE KVM namespace */ > > > "__AArch64ADRPThunk_", /* arm64 lld */ > > > > > > - Sedat - > > > > > > > > -- > > Best Regards > > Masahiro Yamada