From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with archive (Exim 4.43) id 1ItjEf-0002PG-AN for mharc-grub-devel@gnu.org; Sun, 18 Nov 2007 07:26:49 -0500 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1ItjEd-0002Nu-UG for grub-devel@gnu.org; Sun, 18 Nov 2007 07:26:47 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1ItjEc-0002MA-Ez for grub-devel@gnu.org; Sun, 18 Nov 2007 07:26:47 -0500 Received: from [199.232.76.173] (helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1ItjEc-0002Lk-7v for grub-devel@gnu.org; Sun, 18 Nov 2007 07:26:46 -0500 Received: from aybabtu.com ([69.60.117.155]) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1ItjEb-0001MV-Vb for grub-devel@gnu.org; Sun, 18 Nov 2007 07:26:46 -0500 Received: from [192.168.10.6] (helo=thorin) by aybabtu.com with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.63) (envelope-from ) id 1ItjEa-0005lT-KZ for grub-devel@gnu.org; Sun, 18 Nov 2007 13:26:45 +0100 Received: from rmh by thorin with local (Exim 4.63) (envelope-from ) id 1ItjEK-00054Z-Si for grub-devel@gnu.org; Sun, 18 Nov 2007 13:26:28 +0100 Date: Sun, 18 Nov 2007 13:26:28 +0100 From: Robert Millan To: The development of GRUB 2 Message-ID: <20071118122628.GB19370@thorin> References: <471E4628.9030706@t-online.de> <20071118112737.GB16674@thorin> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20071118112737.GB16674@thorin> Organization: free as in freedom X-Message-Flag: Microsoft discourages use of Outlook. X-Debbugs-No-Ack: true User-Agent: Mutt/1.5.13 (2006-08-11) X-detected-kernel: by monty-python.gnu.org: Genre and OS details not recognized. Subject: Re: [PATCH] Fix eisa_mmap evaluation, add memory existence check X-BeenThere: grub-devel@gnu.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: The development of GRUB 2 List-Id: The development of GRUB 2 List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 18 Nov 2007 12:26:48 -0000 On Sun, Nov 18, 2007 at 12:27:37PM +0100, Robert Millan wrote: > On Tue, Oct 23, 2007 at 09:06:16PM +0200, Christian Franke wrote: > > +/* Check memory address */ > > +static int > > +addr_is_valid (grub_addr_t addr) > > +{ > > + volatile unsigned char * p = (volatile unsigned char *)addr; > > + unsigned char x, y; > > + x = *p; > > + *p = x ^ 0xcf; > > + y = *p; > > + *p = x; > > + return y == (x ^ 0xcf); > > +} > > 0xff would be better IMO. Uhm actually, I just remembered that we have the ~ operator precisely for that :-) -- Robert Millan I know my rights; I want my phone call! What use is a phone call, if you are unable to speak? (as seen on /.)