Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753675Ab3DLO5b (ORCPT ); Fri, 12 Apr 2013 10:57:31 -0400 Received: from terminus.zytor.com ([198.137.202.10]:56285 "EHLO mail.zytor.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752989Ab3DLO53 (ORCPT ); Fri, 12 Apr 2013 10:57:29 -0400 Message-ID: <5168208B.7050107@zytor.com> Date: Fri, 12 Apr 2013 07:56:11 -0700 From: "H. Peter Anvin" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:17.0) Gecko/20130311 Thunderbird/17.0.4 MIME-Version: 1.0 To: Vivek Goyal CC: Yinghai Lu , Thomas Renninger , Simon Horman , "kexec@lists.infradead.org" , "Eric W. Biederman" , Cliff Wickman , Linux Kernel Mailing List , Dave Hansen Subject: Re: [PATCH 5/5] kexec: X86: Pass memory ranges via e820 table instead of memmap= boot parameter References: <1365683207-42425-1-git-send-email-trenn@suse.de> <1365683207-42425-6-git-send-email-trenn@suse.de> <5166D18A.7090800@zytor.com> <20130412143104.GA4301@redhat.com> In-Reply-To: <20130412143104.GA4301@redhat.com> X-Enigmail-Version: 1.5.1 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 Content-Length: 824 Lines: 22 On 04/12/2013 07:31 AM, Vivek Goyal wrote: >> >> I also have to admit that I don't see the difference between /dev/mem >> and /dev/oldmem, as the former allows access to memory ranges outside >> the ones used by the current kernel, which is what the oldmem device >> seems to be intended to od. > > I think one difference seems to be that /dev/mem assumes that validly > accessed memory is already mapped in kernel while /dev/oldmeme assumes > it is not mapped and creates temporary mappings explicitly. > Dave Hansen has been working on fixing /dev/mem for HIGHMEM. -hpa -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/