Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760154AbZFXPbn (ORCPT ); Wed, 24 Jun 2009 11:31:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1759427AbZFXPbO (ORCPT ); Wed, 24 Jun 2009 11:31:14 -0400 Received: from moutng.kundenserver.de ([212.227.126.186]:53435 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1758059AbZFXPbL (ORCPT ); Wed, 24 Jun 2009 11:31:11 -0400 From: Arnd Bergmann To: Marco Stornelli Subject: Re: [PATCH 06/14] Pramfs: Include files Date: Wed, 24 Jun 2009 17:30:36 +0200 User-Agent: KMail/1.11.90 (Linux/2.6.30-9-generic; KDE/4.2.90; x86_64; ; ) Cc: David Woodhouse , =?iso-8859-1?q?J=F6rn_Engel?= , Sam Ravnborg , Tim Bird , Chris Simmonds , Linux FS Devel , Linux Embedded , Linux Kernel References: <4A33A7EC.6070008@gmail.com> <200906232355.34134.arnd@arndb.de> <2ea1731b0906232332n2488d452p27419eac7edab7e4@mail.gmail.com> In-Reply-To: <2ea1731b0906232332n2488d452p27419eac7edab7e4@mail.gmail.com> X-Face: I@=L^?./?$U,EK.)V[4*>`zSqm0>65YtkOe>TFD'!aw?7OVv#~5xd\s,[~w]-J!)|%=]> =?utf-8?q?+=0A=09=7EohchhkRGW=3F=7C6=5FqTmkd=5Ft=3FLZC=23Q-=60=2E=60Y=2Ea=5E?= =?utf-8?q?3zb?=) =?utf-8?q?+U-JVN=5DWT=25cw=23=5BYo0=267C=26bL12wWGlZi=0A=09=7EJ=3B=5Cwg?= =?utf-8?q?=3B3zRnz?=,J"CT_)=\H'1/{?SR7GDu?WIopm.HaBG=QYj"NZD_[zrM\Gip^U MIME-Version: 1.0 Content-Type: Text/Plain; charset="iso-8859-1" Content-Transfer-Encoding: 7bit Message-Id: <200906241730.37151.arnd@arndb.de> X-Provags-ID: V01U2FsdGVkX1+tmutT8ow4rNOciFZ6nyyBpruULl0giwuPlBN VIXgoBLAev+V2inbq+GtNnbE3H3Oka0RW4vE/0vgdLts0uL/2h xMyndbuvko1y+m80BZcew== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 767 Lines: 18 On Wednesday 24 June 2009, Marco Stornelli wrote: > > Actually, reading from /dev/mem is only valid on real RAM. If the nvram > > is part of an IO memory mapping, you have to do mmap()+memcpy() rather > > than read(). So dd won't do it, but it's still easy to read from user > > space. > > For "security" reasons pram reserve the region of memory with > reserve_mem_region_exclusive()..... That will only prevent other device drivers from stepping on it, /dev/mem does not care about mem_region reservations. Arnd <>< -- 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/