From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx198.postini.com [74.125.245.198]) by kanga.kvack.org (Postfix) with SMTP id 303AE6B0033 for ; Thu, 16 May 2013 20:08:31 -0400 (EDT) Received: from m3.gw.fujitsu.co.jp (unknown [10.0.50.73]) by fgwmail6.fujitsu.co.jp (Postfix) with ESMTP id 52E7B3EE0BD for ; Fri, 17 May 2013 09:08:29 +0900 (JST) Received: from smail (m3 [127.0.0.1]) by outgoing.m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 40BB145DEBB for ; Fri, 17 May 2013 09:08:29 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (s3.gw.fujitsu.co.jp [10.0.50.93]) by m3.gw.fujitsu.co.jp (Postfix) with ESMTP id 28D5F45DEB6 for ; Fri, 17 May 2013 09:08:29 +0900 (JST) Received: from s3.gw.fujitsu.co.jp (localhost.localdomain [127.0.0.1]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id 17007E08002 for ; Fri, 17 May 2013 09:08:29 +0900 (JST) Received: from m1000.s.css.fujitsu.com (m1000.s.css.fujitsu.com [10.240.81.136]) by s3.gw.fujitsu.co.jp (Postfix) with ESMTP id C0E7F1DB8038 for ; Fri, 17 May 2013 09:08:28 +0900 (JST) Message-ID: <519574E8.5020704@jp.fujitsu.com> Date: Fri, 17 May 2013 09:08:08 +0900 From: HATAYAMA Daisuke MIME-Version: 1.0 Subject: Re: [PATCH v6 2/8] vmcore: allocate buffer for ELF headers on page-size alignment References: <20130515090507.28109.28956.stgit@localhost6.localdomain6> <20130515090551.28109.73350.stgit@localhost6.localdomain6> <20130516165105.GB8726@redhat.com> In-Reply-To: <20130516165105.GB8726@redhat.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Vivek Goyal Cc: ebiederm@xmission.com, akpm@linux-foundation.org, cpw@sgi.com, kumagai-atsushi@mxc.nes.nec.co.jp, lisa.mitchell@hp.com, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, zhangyanfei@cn.fujitsu.com, jingbai.ma@hp.com, linux-mm@kvack.org, riel@redhat.com, walken@google.com, hughd@google.com, kosaki.motohiro@jp.fujitsu.com (2013/05/17 1:51), Vivek Goyal wrote: > On Wed, May 15, 2013 at 06:05:51PM +0900, HATAYAMA Daisuke wrote: > > [..] >> @@ -398,9 +403,7 @@ static int __init process_ptload_program_headers_elf64(char *elfptr, >> phdr_ptr = (Elf64_Phdr*)(elfptr + sizeof(Elf64_Ehdr)); /* PT_NOTE hdr */ >> >> /* First program header is PT_NOTE header. */ >> - vmcore_off = sizeof(Elf64_Ehdr) + >> - (ehdr_ptr->e_phnum) * sizeof(Elf64_Phdr) + >> - phdr_ptr->p_memsz; /* Note sections */ >> + vmcore_off = elfsz + roundup(phdr_ptr->p_memsz, PAGE_SIZE); >> >> for (i = 0; i < ehdr_ptr->e_phnum; i++, phdr_ptr++) { >> if (phdr_ptr->p_type != PT_LOAD) >> @@ -435,9 +438,7 @@ static int __init process_ptload_program_headers_elf32(char *elfptr, >> phdr_ptr = (Elf32_Phdr*)(elfptr + sizeof(Elf32_Ehdr)); /* PT_NOTE hdr */ >> >> /* First program header is PT_NOTE header. */ >> - vmcore_off = sizeof(Elf32_Ehdr) + >> - (ehdr_ptr->e_phnum) * sizeof(Elf32_Phdr) + >> - phdr_ptr->p_memsz; /* Note sections */ >> + vmcore_off = elfsz + roundup(phdr_ptr->p_memsz, PAGE_SIZE); > > Hmm.., so we are rounding up ELF note data size too here. I think this belongs > in some other patch as in this patch we are just rounding up the elf > headers. > > This might create read problems too as we have not taking care of this > rounding when adding note to vc_list and it might happen that we are > reading wrong data at a particular offset. > > So may be this rounding up we should do in later patches when we take > care of copying ELF notes data to second kernel. > > Vivek > This is my careless fault. They should have been in 6/7. -- Thanks. HATAYAMA, Daisuke -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org