From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755836Ab3E0Bts (ORCPT ); Sun, 26 May 2013 21:49:48 -0400 Received: from fgwmail6.fujitsu.co.jp ([192.51.44.36]:50532 "EHLO fgwmail6.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755718Ab3E0Btr (ORCPT ); Sun, 26 May 2013 21:49:47 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v1.8.9 X-SHieldMailCheckerPolicyVersion: FJ-ISEC-20120718-2 Message-ID: <51A2BBA7.50607@jp.fujitsu.com> Date: Mon, 27 May 2013 10:49:27 +0900 From: HATAYAMA Daisuke User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:17.0) Gecko/20130509 Thunderbird/17.0.6 MIME-Version: 1.0 To: Maxim Uvarov CC: Andrew Morton , riel@redhat.com, hughd@google.com, jingbai.ma@hp.com, "kexec@lists.infradead.org" , linux-kernel@vger.kernel.org, lisa.mitchell@hp.com, linux-mm@kvack.org, Atsushi Kumagai , "Eric W. Biederman" , kosaki.motohiro@jp.fujitsu.com, zhangyanfei@cn.fujitsu.com, walken@google.com, Cliff Wickman , Vivek Goyal Subject: Re: [PATCH v8 9/9] vmcore: support mmap() on /proc/vmcore References: <20130523052421.13864.83978.stgit@localhost6.localdomain6> <20130523052547.13864.83306.stgit@localhost6.localdomain6> <20130523152445.17549682ae45b5aab3f3cde0@linux-foundation.org> In-Reply-To: Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org (2013/05/24 18:02), Maxim Uvarov wrote: > > > > 2013/5/24 Andrew Morton > > > On Thu, 23 May 2013 14:25:48 +0900 HATAYAMA Daisuke > wrote: > > > This patch introduces mmap_vmcore(). > > > > Don't permit writable nor executable mapping even with mprotect() > > because this mmap() is aimed at reading crash dump memory. > > Non-writable mapping is also requirement of remap_pfn_range() when > > mapping linear pages on non-consecutive physical pages; see > > is_cow_mapping(). > > > > Set VM_MIXEDMAP flag to remap memory by remap_pfn_range and by > > remap_vmalloc_range_pertial at the same time for a single > > vma. do_munmap() can correctly clean partially remapped vma with two > > functions in abnormal case. See zap_pte_range(), vm_normal_page() and > > their comments for details. > > > > On x86-32 PAE kernels, mmap() supports at most 16TB memory only. This > > limitation comes from the fact that the third argument of > > remap_pfn_range(), pfn, is of 32-bit length on x86-32: unsigned long. > > More reviewing and testing, please. > > > Do you have git pull for both kernel and userland changes? I would like to do some more testing on my machines. > > Maxim. Thanks! That's very helpful. -- Thanks. HATAYAMA, Daisuke