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=-15.7 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,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 8F75AC07E95 for ; Thu, 8 Jul 2021 01:09:52 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7A67861CEE for ; Thu, 8 Jul 2021 01:09:52 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230170AbhGHBMc (ORCPT ); Wed, 7 Jul 2021 21:12:32 -0400 Received: from mail.kernel.org ([198.145.29.99]:52812 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230155AbhGHBMc (ORCPT ); Wed, 7 Jul 2021 21:12:32 -0400 Received: by mail.kernel.org (Postfix) with ESMTPSA id 2FD5661CD7; Thu, 8 Jul 2021 01:09:50 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linux-foundation.org; s=korg; t=1625706590; bh=1zZWEV4M9AMwkng/QmgmTgSm3dhtjtkpJhLEDdeG6qI=; h=Date:From:To:Subject:In-Reply-To:From; b=F9zeE/p9SxMk1XrY2WGNoeNQLN5CkZF2R3z91xI2wFp6JQppUTdYPMWX8R8/wfsZq TZopuImUUXxSKJQL39ZUaDaBkhFQWtOlAVKKSNQHMX79xe6O2aIVwQud+5T8NadkdN zd3GDvjRytvdWSxJyNM9Eed8FjEhDUYFj0FM0WB4= Date: Wed, 07 Jul 2021 18:09:49 -0700 From: Andrew Morton To: akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, ast@kernel.org, bhe@redhat.com, bp@alien8.de, catalin.marinas@arm.com, dyoung@redhat.com, evgreen@chromium.org, hsinyi@chromium.org, jeyu@kernel.org, jolsa@kernel.org, khlebnikov@yandex-team.ru, linux-mm@kvack.org, linux@rasmusvillemoes.dk, mingo@redhat.com, mm-commits@vger.kernel.org, pmladek@suse.com, rostedt@goodmis.org, sashal@kernel.org, sergey.senozhatsky@gmail.com, swboyd@chromium.org, tglx@linutronix.de, torvalds@linux-foundation.org, vgoyal@redhat.com, will@kernel.org, willy@infradead.org Subject: [patch 43/54] kdump: use vmlinux_build_id to simplify Message-ID: <20210708010949.MeQpwOBhn%akpm@linux-foundation.org> In-Reply-To: <20210707175950.eceddb86c6c555555d4730e2@linux-foundation.org> User-Agent: s-nail v14.8.16 Precedence: bulk Reply-To: linux-kernel@vger.kernel.org List-ID: X-Mailing-List: mm-commits@vger.kernel.org From: Stephen Boyd Subject: kdump: use vmlinux_build_id to simplify We can use the vmlinux_build_id array here now instead of open coding it. This mostly consolidates code. Link: https://lkml.kernel.org/r/20210511003845.2429846-14-swboyd@chromium.org Signed-off-by: Stephen Boyd 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: Andy Shevchenko Cc: Borislav Petkov Cc: Catalin Marinas Cc: Ingo Molnar Cc: Konstantin Khlebnikov Cc: Matthew Wilcox Cc: Petr Mladek Cc: Rasmus Villemoes Cc: Sasha Levin Cc: Sergey Senozhatsky Cc: Steven Rostedt Cc: Thomas Gleixner Cc: Will Deacon Signed-off-by: Andrew Morton --- include/linux/buildid.h | 2 - include/linux/crash_core.h | 12 ++++---- kernel/crash_core.c | 50 +---------------------------------- lib/buildid.c | 2 - 4 files changed, 10 insertions(+), 56 deletions(-) --- a/include/linux/buildid.h~kdump-use-vmlinux_build_id-to-simplify +++ a/include/linux/buildid.h @@ -10,7 +10,7 @@ int build_id_parse(struct vm_area_struct __u32 *size); int build_id_parse_buf(const void *buf, unsigned char *build_id, u32 buf_size); -#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) +#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_CRASH_CORE) extern unsigned char vmlinux_build_id[BUILD_ID_SIZE_MAX]; void init_vmlinux_build_id(void); #else --- a/include/linux/crash_core.h~kdump-use-vmlinux_build_id-to-simplify +++ a/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); \ + }) + #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); --- a/kernel/crash_core.c~kdump-use-vmlinux_build_id-to-simplify +++ a/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 } 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_ } VMCOREINFO_OSRELEASE(init_uts_ns.name.release); - add_build_id_vmcoreinfo(); + VMCOREINFO_BUILD_ID(); VMCOREINFO_PAGESIZE(PAGE_SIZE); VMCOREINFO_SYMBOL(init_uts_ns); --- a/lib/buildid.c~kdump-use-vmlinux_build_id-to-simplify +++ a/lib/buildid.c @@ -174,7 +174,7 @@ int build_id_parse_buf(const void *buf, return parse_build_id_buf(build_id, NULL, buf, buf_size); } -#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) +#if IS_ENABLED(CONFIG_STACKTRACE_BUILD_ID) || IS_ENABLED(CONFIG_CRASH_CORE) unsigned char vmlinux_build_id[BUILD_ID_SIZE_MAX] __ro_after_init; /** _