From mboxrd@z Thu Jan  1 00:00:00 1970
Received: from [140.186.70.92] (port=50786 helo=eggs.gnu.org)
	by lists.gnu.org with esmtp (Exim 4.43) id 1PAOgV-00053e-Jr
	for qemu-devel@nongnu.org; Mon, 25 Oct 2010 11:10:04 -0400
Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71)
	(envelope-from <armbru@redhat.com>) id 1PAOdT-00064n-1I
	for qemu-devel@nongnu.org; Mon, 25 Oct 2010 11:06:56 -0400
Received: from mx1.redhat.com ([209.132.183.28]:62721)
	by eggs.gnu.org with esmtp (Exim 4.71)
	(envelope-from <armbru@redhat.com>) id 1PAOdS-00064d-Q7
	for qemu-devel@nongnu.org; Mon, 25 Oct 2010 11:06:54 -0400
Received: from int-mx09.intmail.prod.int.phx2.redhat.com
	(int-mx09.intmail.prod.int.phx2.redhat.com [10.5.11.22])
	by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id o9PF6rwE026650
	(version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=OK)
	for <qemu-devel@nongnu.org>; Mon, 25 Oct 2010 11:06:53 -0400
From: Markus Armbruster <armbru@redhat.com>
Subject: Re: [Qemu-devel] [PATCH 1/2] Keep track of ISA ports ISA device is
	using in qdev.
References: <1287928933-11423-1-git-send-email-gleb@redhat.com>
	<1287928933-11423-2-git-send-email-gleb@redhat.com>
Date: Mon, 25 Oct 2010 17:06:51 +0200
In-Reply-To: <1287928933-11423-2-git-send-email-gleb@redhat.com> (Gleb
	Natapov's message of "Sun, 24 Oct 2010 16:02:12 +0200")
Message-ID: <m3aam2tipg.fsf@blackfin.pond.sub.org>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
List-Id: qemu-devel.nongnu.org
List-Unsubscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=unsubscribe>
List-Archive: <http://lists.nongnu.org/archive/html/qemu-devel>
List-Post: <mailto:qemu-devel@nongnu.org>
List-Help: <mailto:qemu-devel-request@nongnu.org?subject=help>
List-Subscribe: <http://lists.nongnu.org/mailman/listinfo/qemu-devel>,
	<mailto:qemu-devel-request@nongnu.org?subject=subscribe>
To: Gleb Natapov <gleb@redhat.com>
Cc: qemu-devel@nongnu.org

Gleb Natapov <gleb@redhat.com> writes:

> Prevent two devices from claiming the same io port.

Really?

Your new check for double-claim is in the new isa_init_ioport(), which
is for ISADevice only.  Thus, only qdevified ISA devices can opt for
this protection, by calling isa_init_ioport().  It doesn't protect from
devices who don't or can't opt in, such as PCI devices.

Anyway, we already check for double-claim in
register_ioport_{read,write}().  The check has issues --- hw_error() is
wrong there for hot plug.  But it's where the check should be, isn't it?