From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from terminus.zytor.com ([2001:1868:205::10] helo=mail.zytor.com) by merlin.infradead.org with esmtps (Exim 4.80.1 #2 (Red Hat Linux)) id 1VgjBb-0007G4-3v for kexec@lists.infradead.org; Wed, 13 Nov 2013 22:45:23 +0000 Message-ID: <528400DD.3040003@zytor.com> Date: Wed, 13 Nov 2013 14:44:45 -0800 From: "H. Peter Anvin" MIME-Version: 1.0 Subject: Re: /proc/vmcore mmap() failure issue References: <20131113204130.GD7613@redhat.com> <20131113210432.GE7613@redhat.com> <5283EBCD.6070305@zytor.com> <20131113224104.GF7613@redhat.com> In-Reply-To: <20131113224104.GF7613@redhat.com> List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "kexec" Errors-To: kexec-bounces+dwmw2=twosheds.infradead.org@lists.infradead.org To: Vivek Goyal Cc: Baoquan He , Kexec Mailing List , linux kernel mailing list , HATAYAMA Daisuke , "Eric W. Biederman" , Dave Young , WANG Chao On 11/13/2013 02:41 PM, Vivek Goyal wrote: > > Hi Peter, > > I noticed we seem to be trimming away partial pages in memblock. > > memblock_x86_fill() { > /* throw away partial pages */ > memblock_trim_memory(PAGE_SIZE); > } > > But not in e820 hence they show up in /proc/iomem. > Why does /proc/iomem matter? > How about something along the lines as below patch. This fixes my > /proc/vmcore mmap() issue. I'm not sure if what you're seeing is something that is better handled in userspace. -hpa _______________________________________________ kexec mailing list kexec@lists.infradead.org http://lists.infradead.org/mailman/listinfo/kexec From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751790Ab3KMWpb (ORCPT ); Wed, 13 Nov 2013 17:45:31 -0500 Received: from terminus.zytor.com ([198.137.202.10]:57111 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751714Ab3KMWpZ (ORCPT ); Wed, 13 Nov 2013 17:45:25 -0500 Message-ID: <528400DD.3040003@zytor.com> Date: Wed, 13 Nov 2013 14:44:45 -0800 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:24.0) Gecko/20100101 Thunderbird/24.1.0 MIME-Version: 1.0 To: Vivek Goyal CC: linux kernel mailing list , HATAYAMA Daisuke , Kexec Mailing List , Baoquan He , WANG Chao , Dave Young , "Eric W. Biederman" Subject: Re: /proc/vmcore mmap() failure issue References: <20131113204130.GD7613@redhat.com> <20131113210432.GE7613@redhat.com> <5283EBCD.6070305@zytor.com> <20131113224104.GF7613@redhat.com> In-Reply-To: <20131113224104.GF7613@redhat.com> X-Enigmail-Version: 1.6 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 11/13/2013 02:41 PM, Vivek Goyal wrote: > > Hi Peter, > > I noticed we seem to be trimming away partial pages in memblock. > > memblock_x86_fill() { > /* throw away partial pages */ > memblock_trim_memory(PAGE_SIZE); > } > > But not in e820 hence they show up in /proc/iomem. > Why does /proc/iomem matter? > How about something along the lines as below patch. This fixes my > /proc/vmcore mmap() issue. I'm not sure if what you're seeing is something that is better handled in userspace. -hpa