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=-14.7 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS, UNWANTED_LANGUAGE_BODY,USER_AGENT_SANE_1 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 3371DC433B4 for ; Wed, 28 Apr 2021 10:14:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id E6956613C8 for ; Wed, 28 Apr 2021 10:14:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238774AbhD1KO7 (ORCPT ); Wed, 28 Apr 2021 06:14:59 -0400 Received: from us-smtp-delivery-124.mimecast.com ([170.10.133.124]:26939 "EHLO us-smtp-delivery-124.mimecast.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230122AbhD1KO5 (ORCPT ); Wed, 28 Apr 2021 06:14:57 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1619604849; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=VZQFPoKi/jBr5ugRoKa9A9hXUQTIKV1zSbQv433oqxE=; b=TaZMfflQRCGjuo2wpBoDvMfl2IByP67Y2x+QKAyw8GrEgHoxNnqKom0HIt9TU/rx1HZmEx T5l6YLOmtuOc84gpJJgFNUNMh5d20i9eI9NbGF3Lfobji76hp9npsQBe+5N9dqTvzJxqOj aAVXAbetpUmHKYTznf09AA2qo1olYUE= Received: from mimecast-mx01.redhat.com (mimecast-mx01.redhat.com [209.132.183.4]) (Using TLS) by relay.mimecast.com with ESMTP id us-mta-482-GgvlVxVTMCuTzEJ3xmECvQ-1; Wed, 28 Apr 2021 06:14:04 -0400 X-MC-Unique: GgvlVxVTMCuTzEJ3xmECvQ-1 Received: from smtp.corp.redhat.com (int-mx03.intmail.prod.int.phx2.redhat.com [10.5.11.13]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mimecast-mx01.redhat.com (Postfix) with ESMTPS id 28D39803620; Wed, 28 Apr 2021 10:14:03 +0000 (UTC) Received: from localhost (ovpn-13-87.pek2.redhat.com [10.72.13.87]) by smtp.corp.redhat.com (Postfix) with ESMTPS id B49746060F; Wed, 28 Apr 2021 10:13:58 +0000 (UTC) Date: Wed, 28 Apr 2021 18:13:55 +0800 From: Baoquan He To: Stephen Boyd Cc: Andrew Morton , linux-kernel@vger.kernel.org, Jiri Olsa , Alexei Starovoitov , Jessica Yu , Evan Green , Hsin-Yi Wang , Dave Young , Vivek Goyal , kexec@lists.infradead.org Subject: Re: [PATCH v5 13/13] kdump: Use vmlinux_build_id to simplify Message-ID: <20210428101355.GB8374@localhost.localdomain> References: <20210420215003.3510247-1-swboyd@chromium.org> <20210420215003.3510247-14-swboyd@chromium.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210420215003.3510247-14-swboyd@chromium.org> User-Agent: Mutt/1.10.1 (2018-07-13) X-Scanned-By: MIMEDefang 2.79 on 10.5.11.13 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 04/20/21 at 02:50pm, Stephen Boyd wrote: > We can use the vmlinux_build_id array here now instead of open coding > it. This mostly consolidates code. > > Cc: Jiri Olsa > Cc: Alexei Starovoitov > Cc: Jessica Yu > Cc: Evan Green > Cc: Hsin-Yi Wang > Cc: Dave Young > Cc: Baoquan He > Cc: Vivek Goyal > Cc: > Signed-off-by: Stephen Boyd > --- > include/linux/crash_core.h | 12 ++++----- > kernel/crash_core.c | 50 ++------------------------------------ > 2 files changed, 8 insertions(+), 54 deletions(-) > > diff --git a/include/linux/crash_core.h b/include/linux/crash_core.h > index 206bde8308b2..de62a722431e 100644 > --- a/include/linux/crash_core.h > +++ b/include/linux/crash_core.h > @@ -38,8 +38,12 @@ phys_addr_t paddr_vmcoreinfo_note(void); > > #define VMCOREINFO_OSRELEASE(value) \ > vmcoreinfo_append_str("OSRELEASE=%s\n", value) > -#define VMCOREINFO_BUILD_ID(value) \ > - vmcoreinfo_append_str("BUILD-ID=%s\n", value) > +#define VMCOREINFO_BUILD_ID() \ > + ({ \ > + static_assert(sizeof(vmlinux_build_id) == 20); \ > + vmcoreinfo_append_str("BUILD-ID=%20phN\n", vmlinux_build_id); \ Since there has been static_assert at above, can we remove the magic number '20'? And I checked format_decode(), didn't find which type corresponds to 'N', could you tell? Other than these, this patch looks good to me, thanks for the effort. Thanks Baoquan > + }) > + > #define VMCOREINFO_PAGESIZE(value) \ > vmcoreinfo_append_str("PAGESIZE=%ld\n", value) > #define VMCOREINFO_SYMBOL(name) \ > @@ -69,10 +73,6 @@ extern unsigned char *vmcoreinfo_data; > extern size_t vmcoreinfo_size; > extern u32 *vmcoreinfo_note; > > -/* raw contents of kernel .notes section */ > -extern const void __start_notes __weak; > -extern const void __stop_notes __weak; > - > Elf_Word *append_elf_note(Elf_Word *buf, char *name, unsigned int type, > void *data, size_t data_len); > void final_note(Elf_Word *buf); > diff --git a/kernel/crash_core.c b/kernel/crash_core.c > index 825284baaf46..29cc15398ee4 100644 > --- a/kernel/crash_core.c > +++ b/kernel/crash_core.c > @@ -4,6 +4,7 @@ > * Copyright (C) 2002-2004 Eric Biederman > */ > > +#include > #include > #include > #include > @@ -378,53 +379,6 @@ phys_addr_t __weak paddr_vmcoreinfo_note(void) > } > EXPORT_SYMBOL(paddr_vmcoreinfo_note); > > -#define NOTES_SIZE (&__stop_notes - &__start_notes) > -#define BUILD_ID_MAX SHA1_DIGEST_SIZE > -#define NT_GNU_BUILD_ID 3 > - > -struct elf_note_section { > - struct elf_note n_hdr; > - u8 n_data[]; > -}; > - > -/* > - * Add build ID from .notes section as generated by the GNU ld(1) > - * or LLVM lld(1) --build-id option. > - */ > -static void add_build_id_vmcoreinfo(void) > -{ > - char build_id[BUILD_ID_MAX * 2 + 1]; > - int n_remain = NOTES_SIZE; > - > - while (n_remain >= sizeof(struct elf_note)) { > - const struct elf_note_section *note_sec = > - &__start_notes + NOTES_SIZE - n_remain; > - const u32 n_namesz = note_sec->n_hdr.n_namesz; > - > - if (note_sec->n_hdr.n_type == NT_GNU_BUILD_ID && > - n_namesz != 0 && > - !strcmp((char *)¬e_sec->n_data[0], "GNU")) { > - if (note_sec->n_hdr.n_descsz <= BUILD_ID_MAX) { > - const u32 n_descsz = note_sec->n_hdr.n_descsz; > - const u8 *s = ¬e_sec->n_data[n_namesz]; > - > - s = PTR_ALIGN(s, 4); > - bin2hex(build_id, s, n_descsz); > - build_id[2 * n_descsz] = '\0'; > - VMCOREINFO_BUILD_ID(build_id); > - return; > - } > - pr_warn("Build ID is too large to include in vmcoreinfo: %u > %u\n", > - note_sec->n_hdr.n_descsz, > - BUILD_ID_MAX); > - return; > - } > - n_remain -= sizeof(struct elf_note) + > - ALIGN(note_sec->n_hdr.n_namesz, 4) + > - ALIGN(note_sec->n_hdr.n_descsz, 4); > - } > -} > - > static int __init crash_save_vmcoreinfo_init(void) > { > vmcoreinfo_data = (unsigned char *)get_zeroed_page(GFP_KERNEL); > @@ -443,7 +397,7 @@ static int __init crash_save_vmcoreinfo_init(void) > } > > VMCOREINFO_OSRELEASE(init_uts_ns.name.release); > - add_build_id_vmcoreinfo(); > + VMCOREINFO_BUILD_ID(); > VMCOREINFO_PAGESIZE(PAGE_SIZE); > > VMCOREINFO_SYMBOL(init_uts_ns); > -- > https://chromeos.dev > > > _______________________________________________ > kexec mailing list > kexec@lists.infradead.org > http://lists.infradead.org/mailman/listinfo/kexec >