Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756676Ab1FUNDW (ORCPT ); Tue, 21 Jun 2011 09:03:22 -0400 Received: from mx3-phx2.redhat.com ([209.132.183.24]:54042 "EHLO mx3-phx2.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756663Ab1FUNDT convert rfc822-to-8bit (ORCPT ); Tue, 21 Jun 2011 09:03:19 -0400 Date: Tue, 21 Jun 2011 09:03:18 -0400 (EDT) From: Dave Anderson To: Cong Wang Cc: Linux Kernel Mailing List Message-ID: <876358254.119683.1308661398718.JavaMail.root@zmail05.collab.prod.int.phx2.redhat.com> In-Reply-To: <4E000776.7000504@redhat.com> Subject: Re: [PATCH 00/10] Enhance /dev/mem to allow read/write of arbitrary physical addresses MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8BIT X-Originating-IP: [10.5.5.71] X-Mailer: Zimbra 6.0.9_GA_2686 (ZimbraWebClient - FF3.0 (Linux)/6.0.9_GA_2686) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1238 Lines: 36 ----- Original Message ----- > 于 2011年06月20日 21:24, Dave Anderson 写道: > >> On Mon, Jun 20, 2011 at 10:42:47, Amerigo Wang > > > > I don't know what you mean by I "didn't consider it", because > > the crash utility does support using /proc/kcore as an alternative > > live memory source. > > Sorry, I recall that in our last discussion you didn't > mention this. But it is good to know that crash supports this! > > > > > The problem is that /proc/kcore can only access highmem if it > > is mapped as kernel virtual address. So it cannot read 32-bit > > highmem PTE's, user-space memory, etc. > > > > Hmm, looking at the code, you are right, it only has > low memory in kernel space. > > But what's the problem of adding highmem into kcore? :-/ > > Thanks. /proc/kcore was presumably designed for use by gdb with a vmlinux namelist, and like user-space core dumps, the PT_LOAD segments reference virtual address regions with p_vaddr/p_paddr pairs. Dave -- 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/