From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933840Ab3BNKLy (ORCPT ); Thu, 14 Feb 2013 05:11:54 -0500 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:43552 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933788Ab3BNKLv (ORCPT ); Thu, 14 Feb 2013 05:11:51 -0500 From: HATAYAMA Daisuke Subject: [PATCH 01/13] vmcore: allocate buffer for ELF headers on page-size alignment To: ebiederm@xmission.com, vgoyal@redhat.com, cpw@sgi.com, kumagai-atsushi@mxc.nes.nec.co.jp, lisa.mitchell@hp.com Cc: kexec@lists.infradead.org, linux-kernel@vger.kernel.org Date: Thu, 14 Feb 2013 19:11:48 +0900 Message-ID: <20130214101148.22466.97735.stgit@localhost6.localdomain6> In-Reply-To: <20130214100945.22466.4172.stgit@localhost6.localdomain6> References: <20130214100945.22466.4172.stgit@localhost6.localdomain6> User-Agent: StGIT/0.14.3 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Allocate buffer for ELF headers on page-size aligned boudary to satisfy mmap() requirement. For this, __get_free_pages() is used instead of kmalloc(). Also, later patch will decrease actually used buffer size for ELF headers, so it's necessary to keep original buffer size and actually used buffer size separately. elfcorebuf_sz_orig keeps the original one and elfcorebuf_sz the actually used one. Signed-off-by: HATAYAMA Daisuke --- fs/proc/vmcore.c | 30 +++++++++++++++++++++--------- 1 files changed, 21 insertions(+), 9 deletions(-) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index 0d5071d..85714c3 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -30,6 +30,7 @@ static LIST_HEAD(vmcore_list); /* Stores the pointer to the buffer containing kernel elf core headers. */ static char *elfcorebuf; static size_t elfcorebuf_sz; +static size_t elfcorebuf_sz_orig; /* Total size of vmcore file. */ static u64 vmcore_size; @@ -560,26 +561,31 @@ static int __init parse_crash_elf64_headers(void) /* Read in all elf headers. */ elfcorebuf_sz = sizeof(Elf64_Ehdr) + ehdr.e_phnum * sizeof(Elf64_Phdr); - elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL); + elfcorebuf_sz_orig = elfcorebuf_sz; + elfcorebuf = (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(elfcorebuf_sz)); if (!elfcorebuf) return -ENOMEM; addr = elfcorehdr_addr; rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0); if (rc < 0) { - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); return rc; } /* Merge all PT_NOTE headers into one. */ rc = merge_note_headers_elf64(elfcorebuf, &elfcorebuf_sz, &vmcore_list); if (rc) { - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); return rc; } rc = process_ptload_program_headers_elf64(elfcorebuf, elfcorebuf_sz, &vmcore_list); if (rc) { - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); return rc; } set_vmcore_list_offsets_elf64(elfcorebuf, &vmcore_list); @@ -616,26 +622,31 @@ static int __init parse_crash_elf32_headers(void) /* Read in all elf headers. */ elfcorebuf_sz = sizeof(Elf32_Ehdr) + ehdr.e_phnum * sizeof(Elf32_Phdr); - elfcorebuf = kmalloc(elfcorebuf_sz, GFP_KERNEL); + elfcorebuf_sz_orig = elfcorebuf_sz; + elfcorebuf = (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO, + get_order(elfcorebuf_sz)); if (!elfcorebuf) return -ENOMEM; addr = elfcorehdr_addr; rc = read_from_oldmem(elfcorebuf, elfcorebuf_sz, &addr, 0); if (rc < 0) { - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); return rc; } /* Merge all PT_NOTE headers into one. */ rc = merge_note_headers_elf32(elfcorebuf, &elfcorebuf_sz, &vmcore_list); if (rc) { - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); return rc; } rc = process_ptload_program_headers_elf32(elfcorebuf, elfcorebuf_sz, &vmcore_list); if (rc) { - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); return rc; } set_vmcore_list_offsets_elf32(elfcorebuf, &vmcore_list); @@ -719,7 +730,8 @@ void vmcore_cleanup(void) list_del(&m->list); kfree(m); } - kfree(elfcorebuf); + free_pages((unsigned long)elfcorebuf, + get_order(elfcorebuf_sz_orig)); elfcorebuf = NULL; } EXPORT_SYMBOL_GPL(vmcore_cleanup);