From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MLIt5-0006ko-Bz for qemu-devel@nongnu.org; Mon, 29 Jun 2009 11:35:19 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MLIt0-0006jP-P5 for qemu-devel@nongnu.org; Mon, 29 Jun 2009 11:35:18 -0400 Received: from [199.232.76.173] (port=60083 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MLIsy-0006jL-Ux for qemu-devel@nongnu.org; Mon, 29 Jun 2009 11:35:13 -0400 Received: from mx2.redhat.com ([66.187.237.31]:56444) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MLIsy-0008RO-7m for qemu-devel@nongnu.org; Mon, 29 Jun 2009 11:35:12 -0400 Message-ID: <4A48DF8B.7050606@redhat.com> Date: Mon, 29 Jun 2009 18:36:43 +0300 From: Avi Kivity MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH] Implement PC port80 debug register. References: <1246262725-23825-1-git-send-email-jljusten@gmail.com> <4A48C5F5.6030402@codemonkey.ws> <4A48CE67.9070705@redhat.com> <2a50f7880906290826t4128b11dyc68a36fd01e8208c@mail.gmail.com> In-Reply-To: <2a50f7880906290826t4128b11dyc68a36fd01e8208c@mail.gmail.com> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jordan Justen Cc: qemu-devel@nongnu.org On 06/29/2009 06:26 PM, Jordan Justen wrote: > Avi, > > Well, I am not sure if this it globally the case for PC motherboards, > but in my experience, it has been read/write. It's just some random memory that might not actually be grounded in reality. > > At least for a system such as qemu, it make it difficult to use the > port80 checkpoint of software without being able to read the last > value written. Why would software ever need to read it? You want a monitor command so the user can read it. I don't recall ever seeing a read of port 80 (I don't have any objections to that though). -- error compiling committee.c: too many arguments to function