From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754902AbbGPIse (ORCPT ); Thu, 16 Jul 2015 04:48:34 -0400 Received: from mx1.redhat.com ([209.132.183.28]:39437 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753958AbbGPIsb (ORCPT ); Thu, 16 Jul 2015 04:48:31 -0400 From: Baoquan He To: linux-kernel@vger.kernel.org, ncroxon@redhat.com, dyoung@redhat.com, mhuang@redhat.com Cc: Baoquan He Subject: [RHEL6.8 Patch 13/19] vmcore: calculate vmcore file size from buffer size and total size of vmcore objects Date: Thu, 16 Jul 2015 16:47:11 +0800 Message-Id: <1437036437-25408-17-git-send-email-bhe@redhat.com> In-Reply-To: <1437036437-25408-1-git-send-email-bhe@redhat.com> References: <1437036437-25408-1-git-send-email-bhe@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Resolves: bz1097904 https://bugzilla.redhat.com/show_bug.cgi?id=1097904 This is back ported from upstream. commit 591ff71664e764a3806e341370f3c758cb2e7e3c Author: HATAYAMA Daisuke Date: Wed Jul 3 15:02:22 2013 -0700 vmcore: calculate vmcore file size from buffer size and total size of vmcore objects The previous patches newly added holes before each chunk of memory and the holes need to be count in vmcore file size. There are two ways to count file size in such a way: 1) suppose m is a poitner to the last vmcore object in vmcore_list. Then file size is (m->offset + m->size), or 2) calculate sum of size of buffers for ELF header, program headers, ELF note segments and objects in vmcore_list. Although 1) is more direct and simpler than 2), 2) seems better in that it reflects internal object structure of /proc/vmcore. Thus, this patch changes get_vmcore_size_elf{64, 32} so that it calculates size in the way of 2). As a result, both get_vmcore_size_elf{64, 32} have the same definition. Merge them as get_vmcore_size. Signed-off-by: HATAYAMA Daisuke Acked-by: Vivek Goyal Cc: KOSAKI Motohiro Cc: Atsushi Kumagai Cc: Lisa Mitchell Cc: Zhang Yanfei Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds Signed-off-by: Baoquan He --- fs/proc/vmcore.c | 44 +++++++++++--------------------------------- 1 file changed, 11 insertions(+), 33 deletions(-) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index 6849c3f..88af2af 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -199,36 +199,15 @@ static struct vmcore* __init get_new_element(void) return kzalloc(sizeof(struct vmcore), GFP_KERNEL); } -static u64 __init get_vmcore_size_elf64(char *elfptr, size_t elfsz) +static u64 __init get_vmcore_size(size_t elfsz, size_t elfnotesegsz, + struct list_head *vc_list) { - int i; u64 size; - Elf64_Ehdr *ehdr_ptr; - Elf64_Phdr *phdr_ptr; - - ehdr_ptr = (Elf64_Ehdr *)elfptr; - phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); - size = elfsz; - for (i = 0; i < ehdr_ptr->e_phnum; i++) { - size += phdr_ptr->p_memsz; - phdr_ptr++; - } - return size; -} - -static u64 __init get_vmcore_size_elf32(char *elfptr, size_t elfsz) -{ - int i; - u64 size; - Elf32_Ehdr *ehdr_ptr; - Elf32_Phdr *phdr_ptr; + struct vmcore *m; - ehdr_ptr = (Elf32_Ehdr *)elfptr; - phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); - size = elfsz; - for (i = 0; i < ehdr_ptr->e_phnum; i++) { - size += phdr_ptr->p_memsz; - phdr_ptr++; + size = elfsz + elfnotesegsz; + list_for_each_entry(m, vc_list, list) { + size += m->size; } return size; } @@ -854,21 +833,20 @@ static int __init parse_crash_elf_headers(void) rc = parse_crash_elf64_headers(); if (rc) return rc; - - /* Determine vmcore size. */ - vmcore_size = get_vmcore_size_elf64(elfcorebuf, elfcorebuf_sz); } else if (e_ident[EI_CLASS] == ELFCLASS32) { rc = parse_crash_elf32_headers(); if (rc) return rc; - - /* Determine vmcore size. */ - vmcore_size = get_vmcore_size_elf32(elfcorebuf, elfcorebuf_sz); } else { printk(KERN_WARNING "Warning: Core image elf header is not" " sane\n"); return -EINVAL; } + + /* Determine vmcore size. */ + vmcore_size = get_vmcore_size(elfcorebuf_sz, elfnotes_sz, + &vmcore_list); + return 0; } -- 2.1.0