From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753302AbbJMWyT (ORCPT ); Tue, 13 Oct 2015 18:54:19 -0400 Received: from mga14.intel.com ([192.55.52.115]:1952 "EHLO mga14.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751329AbbJMWyR (ORCPT ); Tue, 13 Oct 2015 18:54:17 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.17,680,1437462000"; d="scan'208";a="791994030" Date: Tue, 13 Oct 2015 16:54:15 -0600 From: Ross Zwisler To: Ross Zwisler Cc: linux-kernel@vger.kernel.org, Alexander Viro , Ingo Molnar , Jonathan Corbet , Peter Zijlstra , linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, Dan Williams , linux-nvdimm@ml01.01.org, Matthew Wilcox Subject: Re: [PATCH 0/2] Add explicit coredump filtering for DAX mappings Message-ID: <20151013225415.GA25616@linux.intel.com> Mail-Followup-To: Ross Zwisler , linux-kernel@vger.kernel.org, Alexander Viro , Ingo Molnar , Jonathan Corbet , Peter Zijlstra , linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, Dan Williams , linux-nvdimm@lists.01.org, Matthew Wilcox References: <1444084417-19192-1-git-send-email-ross.zwisler@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1444084417-19192-1-git-send-email-ross.zwisler@linux.intel.com> User-Agent: Mutt/1.5.23 (2014-03-12) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, Oct 05, 2015 at 04:33:35PM -0600, Ross Zwisler wrote: > Add two new flags to the existing coredump mechanism for ELF files to allow > us to explicitly filter DAX mappings. This is desirable because DAX > mappings, like hugetlb mappings, have the potential to be very large. > > The coredump code relies on get_user_page() to populate the coredump file > with the appropriate data, and for DAX mappings this currently fails. This > results in a hole being placed in the coredump file, so you end up reading > back zeros. Once the get_user_pages() patch series from Dan Williams [1] > is merged, DAX core dumps will give real data. > > I have a patch ready for core(5) to update the documentation on the new > filtering flags. I'll send it out once this gets merged. > > [1] http://thread.gmane.org/gmane.linux.kernel.mm/139026 > > Ross Zwisler (2): > coredump: add DAX filtering for ELF coredumps > coredump: add DAX filtering for FDPIC ELF coredumps > > Documentation/filesystems/proc.txt | 22 ++++++++++++---------- > fs/binfmt_elf.c | 10 ++++++++++ > fs/binfmt_elf_fdpic.c | 15 +++++++++++++++ > include/linux/sched.h | 4 +++- > 4 files changed, 40 insertions(+), 11 deletions(-) > > -- > 2.1.0 Ping?