From mboxrd@z Thu Jan 1 00:00:00 1970 From: Gerd Hoffmann Subject: Re: [PATCH 20/39] virtio-pci: convert to memory API Date: Tue, 02 Aug 2011 18:28:07 +0200 Message-ID: <4E382597.4020108@redhat.com> References: <1312135082-31985-1-git-send-email-avi@redhat.com> <1312135082-31985-21-git-send-email-avi@redhat.com> <20110801082600.GD5439@redhat.com> <4E367370.6070100@redhat.com> <20110801195343.GA16682@redhat.com> <4E37C092.8060108@redhat.com> Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Cc: "Michael S. Tsirkin" , Anthony Liguori , qemu-devel@nongnu.org, kvm@vger.kernel.org To: Avi Kivity Return-path: Received: from mx1.redhat.com ([209.132.183.28]:18052 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753699Ab1HBQ2O (ORCPT ); Tue, 2 Aug 2011 12:28:14 -0400 In-Reply-To: <4E37C092.8060108@redhat.com> Sender: kvm-owner@vger.kernel.org List-ID: On 08/02/11 11:17, Avi Kivity wrote: > On 08/01/2011 10:53 PM, Michael S. Tsirkin wrote: >> > >> > >> > Just because a memory region becomes visible to the cpu is no reason >> > to have a callback. From the device perspective, it can't tell that >> > it happened. >> >> BTW this is what qxl does, too, conceptually: on config writes, it peeks >> at the bar to detect whether that got unmapped. > > Can you elaborate? why? what does it do? Nothing special, just keep track of the map state and toggle logging if needed, especially make sure to (re-)enable logging after the guest mapped the bar somewhere. I'm pretty sure this can be killed during the conversion as the new memory slot manager will care about this so qxl doesn't has to. cheers, Gerd