From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1M9K0n-0003T3-B1 for qemu-devel@nongnu.org; Wed, 27 May 2009 10:21:45 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1M9K0i-0003Qz-82 for qemu-devel@nongnu.org; Wed, 27 May 2009 10:21:44 -0400 Received: from [199.232.76.173] (port=49658 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1M9K0h-0003Qj-Qx for qemu-devel@nongnu.org; Wed, 27 May 2009 10:21:39 -0400 Received: from e39.co.us.ibm.com ([32.97.110.160]:51657) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1M9K0h-0001zx-0p for qemu-devel@nongnu.org; Wed, 27 May 2009 10:21:39 -0400 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e39.co.us.ibm.com (8.13.1/8.13.1) with ESMTP id n4REHjUv023151 for ; Wed, 27 May 2009 08:17:45 -0600 Received: from d03av04.boulder.ibm.com (d03av04.boulder.ibm.com [9.17.195.170]) by d03relay04.boulder.ibm.com (8.13.8/8.13.8/NCO v9.2) with ESMTP id n4RELOEr190810 for ; Wed, 27 May 2009 08:21:26 -0600 Received: from d03av04.boulder.ibm.com (loopback [127.0.0.1]) by d03av04.boulder.ibm.com (8.12.11.20060308/8.13.3) with ESMTP id n4RELOj1008429 for ; Wed, 27 May 2009 08:21:24 -0600 Message-ID: <4A1D4C57.6010109@us.ibm.com> Date: Wed, 27 May 2009 09:21:11 -0500 From: Anthony Liguori MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH] Change virtio-console to PCI_CLASS_SERIAL_OTHER References: <1243012478.29542.18.camel@blaa> In-Reply-To: <1243012478.29542.18.camel@blaa> 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: Mark McLoughlin Cc: Dor Laor , ajax@redhat.com, qemu-devel Mark McLoughlin wrote: > From: Adam Jackson > > We're using PCI_CLASS_DISPLAY_OTHER now, but qemu-kvm.git is using > PCI_CLASS_OTHERS because: > > "As a PCI_CLASS_DISPLAY_OTHER, it reduces primary display somehow on > Windows XP (possibly Windows disables acceleration since it fails > to find a driver)." > > While this is valid, many versions of X will get confused by it. > Class major number of 0 gets treated as a possibly prehistoric VGA > device, and then the autoconfig logic gets confused trying to figure > out whether the virtio console or the pv vga device are the real VGA. > > We should really set a proper class ID. 0x0780 (serial / other) seems > most appropriate. This shouldn't require any kernel changes, the > modalias for virtio looks like: > > alias: pci:v00001AF4d*sv*sd*bc*sc*i* > > so won't care what the base class or subclass are. > > It shows up in the guest as: > > 00:05.0 Communication controller: Qumranet, Inc. Virtio console > > Signed-off-by: Adam Jackson > Signed-off-by: Mark McLoughlin > We need a mechanism to toggle this for both this and virtio-blk. The reason a toggle is needed is so that 0.11 can create the same device model as 0.10. In principle though, I think both changes are reasonable, we just can't do it unconditionally. Regards, Anthony Liguori